Bio

Clinical Focus


  • Orthopaedic Surgery
  • Palo Alto VAH
  • Menlo Clinic > Orthopaedics

Academic Appointments


Administrative Appointments


  • Member, Stanford University IRB (2006 - Present)
  • Reviewer, Clinical Orthopaedics and Related Research (1993 - Present)
  • Reviewer, Journal of Arthroplasty (1998 - Present)
  • Reviewer, Orthopedics (2011 - Present)
  • Reviewer, Journal of Bone and Joint Surgery (1994 - 2005)
  • Deputy Chief of Service, Department of Functional Restoration (1994 - 2002)

Honors & Awards


  • Alonzo J. Neufeld Award, Western Orthopaedic Association (1995)
  • Alpha Omega Alpha, University of Michigan Medical School (1969)

Professional Education


  • Residency:University of Michigan Hospital (1975) MI
  • Internship:University of Michigan Hospital (1971) MI
  • Board Certification: Orthopaedic Surgery, American Board of Orthopaedic Surgery (1976)
  • Fellowship:Harvard School of Public Health (1982) MA
  • Fellowship:Massachusetts General Hospital (1982) MA
  • Medical Education:University of Michigan (1970) MI
  • Fellowship, Harvard University Med School, Joint Replacement (1982)
  • Residency, U of Michigan, Orthopaedic Surgery (1975)
  • MD, U of Michigan Med School (1970)
  • BA, Hamilton College, Clinton, NY, Chemistry (1965)

Research & Scholarship

Current Research and Scholarly Interests


Clinical Research in Total Joint Replacement

Teaching

2013-14 Courses


Publications

Journal Articles


  • Component alignment during total knee arthroplasty with use of standard or custom instrumentation: a randomized clinical trial using computed tomography for postoperative alignment measurement. journal of bone and joint surgery. American volume Woolson, S. T., Harris, A. H., Wagner, D. W., Giori, N. J. 2014; 96 (5): 366-372

    Abstract

    Patient-specific femoral and tibial cutting blocks produced with use of data from preoperative computed tomography (CT) or magnetic resonance imaging (MRI) scans have been employed recently to optimize component alignment in total knee arthroplasty. We report the results of a randomized controlled trial in which CT scans were used to compare postoperative component alignment between patients treated with custom instruments and those managed with traditional instruments.The in-hospital data and early clinical outcomes, including Knee Society scores, were determined in a randomized clinical trial of forty-seven patients who had undergone a total of forty-eight primary total knee arthroplasties with patient-specific instruments (twenty-two knees) or standard instruments (twenty-six knees). Orientation of the implants was compared by using three-dimensional CT data.No significant differences were found between the study and control groups with respect to any clinical outcome after a minimum of six months of follow-up. The patient-specific tibial cutting block was abandoned in favor of a standard external alignment jig in seven of the twenty-two study knees because of possible malalignment. A detailed analysis of intent-to-treat and per-protocol groups of study and control knees did not show any significant improvement in component alignment, including femoral component rotation in the axial plane, in the patients treated with the custom instruments. The percentage of outliers-defined as less than -3° or more than 3° from the correct orientation of the tibial slope-was significantly higher in the group treated with use of patient-specific blocks than it was in the control group, in both the intent-to-treat (32% versus 8%, p = 0.032) and the per-protocol (47% versus 6%, p = 0.0008) analysis.There were no significant improvements in clinical outcomes or knee component alignment in patients treated with patient-specific cutting blocks as compared with those treated with standard instruments. The group treated with patient-specific cutting blocks had a significantly higher prevalence of malalignment in terms of tibial component slope than the knees treated with standard instruments.Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

    View details for DOI 10.2106/JBJS.L.01722

    View details for PubMedID 24599197

  • MI TKA: a risk factor for early revision surgery. The journal of knee surgery Mayle, R. E., Graw, B. P., Huddleston, H. G., Woolson, S. T., Goodman, S. B., Huddleston, J. I. 2012; 25 (5): 423-427

    Abstract

    Minimal incision total knee arthroplasty (MI TKA) was developed with the potential to decrease surgical trauma, pain, and recovery time. While this procedure has increased in popularity, some surgeons have questioned its safety and long-term efficacy. In this study 58 consecutive revision total knee arthroplasties (TKAs) (57 patients) performed at one academic medical center from 2006 to 2008 are reviewed. Prospectively collected clinical and radiographic data included: incision length, gender, age, time to revision surgery, and primary diagnosis at time of revision. Of these, 34 knees involving infection and rerevision were excluded. Of the remaining 24 knees, 11 knees that met inclusion criteria had undergone MI TKA. There were no differences between the groups with regard to age, diagnosis, body mass index, and gender. Average time to revision was shorter for the MI TKA patients (29 vs. 65 months, p < 0.032, odds ratio 14.7). Reasons for revision were aseptic loosening (55%), pain/stiffness (27%), malrotation (9%), and instability (9%) in the MI TKA group and aseptic loosening (53%), instability (15%), pain/stiffness (8%), malrotation (8%), combined malrotation and instability (8%), and polyethylene wear/osteolysis (8%) in the traditional TKA group. These data suggest that MI TKA may be a risk factor for early revision.

    View details for DOI 10.1055/s-0032-1313757

    View details for PubMedID 23150354

  • Local infiltration analgesia in TKA patients reduces length of stay and postoperative pain scores. Orthopedics Tripuraneni, K. R., Woolson, S. T., Giori, N. J. 2011; 34 (3): 173-?

    Abstract

    Numerous postoperative pain protocols exist for patients undergoing total knee arthroplasty (TKA). We compared the length of stay, early range of motion (ROM), and pain scores of a control group with a femoral nerve block to those of a group with femoral nerve block and local infiltration analgesia following TKA. In a consecutive series of patients undergoing primary TKA at a Veteran's Administration hospital, 40 patients (40 TKAs) who had local infiltration analgesia were compared to a historical group of 43 patients (43 TKAs) who had a long-acting femoral nerve block without local infiltration analgesia. Local infiltration analgesia consisted of intraoperative injection of 150 mL of 300 mg ropivacaine, 30 mg ketorolac, and 500 ?g epinephrine using 50 mL into each of 3 areas: (1) posterior capsule, (2) medial and lateral capsule, and (3) anterior capsule and subcutaneous tissues. A 17-gauge intra-articular catheter was used to inject an additional 100 mg of ropivacaine on postoperative day 1. The control group had a single-shot femoral nerve block using 150 mg of ropivacaine with epinephrine. Mean length of stay for the local infiltration analgesia group compared to controls was 3.2±1.4 days vs 3.8±1.6 days, respectively (P=.03). No significant differences existed in average ROM (6 weeks), discharge hematocrit, transfusions, and temperature. Mean pain scores were lower in the local infiltration analgesia group on postoperative day 1 (P=.04), but not on postoperative day 2 or 3. Maximum visual analog scale scores (P<.01) were reduced in the local infiltration analgesia group. Our early experience with local infiltration analgesia demonstrated a significantly reduced length of stay due to decreased postoperative pain.

    View details for DOI 10.3928/01477447-20110124-11

    View details for PubMedID 21410125

  • Incidence of radiographic unicompartmental arthritis in patients undergoing knee arthroplasty. Orthopedics Woolson, S. T., Shu, B., Giori, N. J. 2010; 33 (11): 798-?

    Abstract

    Unicompartmental knee arthroplasty is increasing in popularity with the advent of less invasive procedures for knee arthritis. The percentage of patients undergoing knee arthroplasty who could be candidates for unicompartmental knee arthroplasty depends on the surgeon's evaluation of the radiographs, and this evaluation may depend on the surgeon's bias regarding partial knee arthroplasty. A retrospective radiographic and chart review was performed on a consecutive series of patients who had undergone tricompartmental knee arthroplasty to determine the percentage of those patients who could have been candidates for unicompartmental knee arthroplasty. Two hundred eighty-eight patients who underwent 308 tricompartmental knee arthroplasties over a 3-year period at a Veteran's Administration Hospital comprised the study group. Assessment of preoperative radiographs was done by 2 surgeons, 1 who favored unicompartmental knee arthroplasty and the other who preferred tricompartmental knee arthroplasty, to determine the percentage of these patients, from each surgeon's viewpoint, who had unicompartmental arthritis. Patients who had radiographic unicompartmental arthritis were then eliminated as candidates for unicompartmental knee arthroplasty, if, on chart review, they had a flexion contracture >10°, an arc of motion <100°, or inflammatory arthritis. The surgeon who was a proponent of unicompartmental knee arthroplasty found that 26% of these patients had acceptable radiologic and clinical indications for unicompartmental knee arthroplasty, whereas the surgeon who had a bias against the procedure felt that only 12% of these patients were unicompartmental knee arthroplasty candidates. A considerable percentage of Veteran's Administration patients undergoing arthroplasty for knee arthritis may be potential candidates for unicompartmental knee arthroplasty, despite the surgeon's bias for or against the procedure.

    View details for DOI 10.3928/01477447-20100924-07

    View details for PubMedID 21053889

  • Minimal Incision Surgery as a Risk Factor for Early Failure of Total Hip Arthroplasty CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Graw, B. P., Woolson, S. T., Huddleston, H. G., Goodman, S. B., Huddleston, J. I. 2010; 468 (9): 2372-2376

    Abstract

    Minimal incision total hip arthroplasty (MI THA) techniques were developed to decrease postoperative pain and recovery time. Although these techniques have increased in popularity, the long-term survivorship of these procedures is unknown.We therefore investigated whether the time to revision in our referral practice was shorter for patients who underwent primary MI THA compared to primary traditional THA.We retrospectively reviewed 46 revision THAs performed during a 3-year period. We excluded revisions performed for infection and rerevisions. Patients with incisions less than or equal to 10 cm were defined as having had MI THA. Fifteen of the 46 patients (33%) had undergone primary MI THA. At the time of primary index THA, the mean ages of the MI and non-MI patients were 65 years and 55 years, respectively.The mean time to revision was 1.4 years for the MI patients compared with 14.7 years for the non-MI patients. Twelve of the 15 patients having MI THA required revision within 2 years of primary THA compared to 4 of the 31 patients without MI surgery (OR = 26.5, 95% CI 4.4-160.0). There were no differences between the groups with regard to age, gender, or body mass index. The most common reasons for revision in the MI THA group were intraoperative fracture and failure of femoral component osseointegration.Our data suggest MI THA may be a risk factor for early revision surgery and the long-term survival therefore may be lower than that for non-MI surgery.Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

    View details for DOI 10.1007/s11999-010-1300-1

    View details for Web of Science ID 000280594200011

    View details for PubMedID 20352391

  • Hylamer vs Conventional Polyethylene in Primary Total Hip Arthroplasty: A Long-Term Case-Control Study of Wear Rates and Osteolysis JOURNAL OF ARTHROPLASTY Huddleston, J. I., Harris, A. H., Atienza, C. A., Woolson, S. T. 2010; 25 (2): 203-207

    Abstract

    The long-term results of Hylamer implants have not been reported previously. Clinical and radiographic results of a consecutive series of 43 patients (45 hips) who had primary total hip arthroplasty using Hylamer liners were compared with those of 37 patients (43 hips) who had conventional liners after 10-year follow-up. The linear wear rates for Hylamer and conventional polyethylene acetabular liners were 0.21 and 0.20 mm/y, respectively. The number of pelvic osteolytic lesions and their size detected on plain radiographs were significantly greater for Hylamer liners. Seven Hylamer hips were revised or are pending revision for osteolysis (16%) compared with 1 control hip. Close radiographic surveillance of patients who have Hylamer liners and evidence of osteolysis found on plain radiographs is warranted.

    View details for DOI 10.1016/j.arth.2009.02.006

    View details for Web of Science ID 000277580900006

    View details for PubMedID 19264443

  • Primary Total Hip Arthroplasty Using an Anterior Approach and a Fracture Table Short-term Results From a Community Hospital JOURNAL OF ARTHROPLASTY Woolson, S. T., Pouliot, M. A., Huddleston, J. I. 2009; 24 (7): 999-1005

    Abstract

    There are no data regarding the efficacy and safety of minimally invasive hip arthroplasty technique performed by community practice orthopedists. The early clinical and radiographic results of primary total hip arthroplasty using a minimally invasive anterior approach to the hip performed on a fracture table were studied. Two hundred thirty-one consecutive patients (247 hips) of 5 community practice surgeons were studied. The average surgical time (164 minutes) and estimated blood loss (858 mL) were more than double, and the major complication rate (9%) was 6 times that reported by an innovator of the procedure. However, no postoperative dislocations occurred. Adequate training is critical to reduce the risk of complications during the learning experience of minimally invasive hip arthroplasty procedures by community practice surgeons.

    View details for DOI 10.1016/j.arth.2009.04.001

    View details for Web of Science ID 000270764600001

    View details for PubMedID 19493651

  • Re: Less invasive total hip arthroplasty: description of a new technique. journal of arthroplasty Woolson, S. T. 2007; 22 (4): 638-639

    View details for PubMedID 17562429

  • A comparison of the results of total hip and knee arthroplasty performed on a teaching service or a private practice service. journal of bone and joint surgery. American volume Woolson, S. T., Kang, M. N. 2007; 89 (3): 601-607

    Abstract

    Active participation of residents and fellows in the performance of total hip and total knee arthroplasties may affect the outcomes of these procedures. We evaluated the early clinical results and complications associated with primary total hip and knee arthroplasties at a hospital that had both university teaching and private practice orthopaedic services.We performed a retrospective study on a consecutive series of 347 patients who had undergone 230 total hip and 171 total knee procedures performed by one attending surgeon. One hundred and sixty-nine patients underwent an arthroplasty during which a resident or fellow on a teaching service assisted the attending surgeon; during these procedures, the resident or fellow performed part of the arthroplasty under the direct supervision of the attending surgeon. Subsequently, 178 patients underwent an arthroplasty performed by the same surgeon without resident or fellow participation.Significantly longer operative times were recorded for both total hip arthroplasty (average, seventy-three compared with sixty-one minutes; p < 0.0001) and total knee arthroplasty (average, eighty compared with seventy-three minutes; p = 0.0028) when the procedures were performed with the participation of residents or fellows. For total hip arthroplasty the complication rates were 8% for the teaching service and 10% for the private practice service, and for total knee arthroplasty they were 3% for each service. With the numbers studied, there were no differences in any clinical outcomes between the groups.Teaching and active participation from residents and fellows during total hip and total knee arthroplasty did not have a detrimental effect on the early clinical results, except for a longer surgical time.

    View details for PubMedID 17332109

  • In the absence of evidence--why bother? A literature review of minimally invasive total hip replacement surgery. Instructional course lectures Woolson, S. T. 2006; 55: 189-193

    Abstract

    Two new total hip replacement (THR) procedures have been termed minimally invasive. It is claimed that these smaller incision techniques reduce soft-tissue trauma, decrease postoperative pain and blood loss, speed recovery, and reduce the length of the hospital stay compared with hip replacement using the standard incision technique. These new procedures use either one small 6- to 10-cm incision through a posterior, lateral, or anterior approach or two very small (a 2.5 cm posterior incision for placement of the femoral component and a 5-cm anterior incision for placement of the acetabular component) incisions to accomplish the same THR procedure that requires a standard length incision of 15 to 20 cm. Controversy exists on whether these small incision THRs are actually minimally invasive. It is debated whether a small skin incision that requires the application of high forces on the soft tissues for exposure of the joint but less muscle dissection will produce less overall trauma to the patient than a larger incision with wider muscle dissection but with lower retraction forces. If small incision THR techniques are less traumatic overall, then they should produce less pain, lower transfusion requirements, a shorter hospital stay, and a faster recovery for patients. The other important issues regarding small incision procedures are whether the decreased visualization provided by these techniques is adequate to prevent a higher complication rate from damage to the surrounding neurovascular structures and outcomes that are equivalent to those found for THR using the standard technique. A review of the literature to date provides no convincing evidence of any significant advantages of small incision THR compared with standard incision THR other than a shorter surgical scar. Comparison studies that prove both significant advantages and low complication rates for small incision THR are needed before these procedures can be recommended for general use.

    View details for PubMedID 16958453

  • Comparison of scars from total hip replacements done with a standard or a mini-incision CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Mow, C. S., Woolson, S. T., Ngarmukos, S. G., Park, E. H., Lorenz, H. P. 2005: 80-85

    Abstract

    Scar cosmesis is one of the proposed benefits of mini-incision total hip replacement as opposed to standard-incision procedures; however, there has been no scientific proof of this clinical outcome. The cosmetic appearances of healed incisions of 34 primary total hip replacement procedures done by one surgeon using either a mini-incision (20 procedures) or a standard-length incision (14 procedures) were compared at an average of 2 years postoperatively. Each scar's appearance was graded independently by two plastic surgeons using a standardized rating system. Patients answered a questionnaire regarding their subjective assessment of their scar. The blinded observers found that more mini-scars (six of 20) were rated poor than standard scars (one of 14) and that more standard-incision patients had scars that were rated good. More mini-incision patients (two of 20 versus zero of 14) had wound-healing problems. All the patients thought that their hip scar was acceptable in appearance, but 30 of 31 patients rated the relief of pain and total hip replacement longevity as higher priorities than scar cosmesis. The cosmesis of mini-incision total hip replacement scars may be inferior to standard-incision scars because of skin and soft tissue damage produced by high retractor pressures needed for exposure using a limited skin incision. Level of Evidence: Therapeutic study, Level II-2 (prospective comparative study). See the Guidelines for Authors for a complete description of levels of evidence.

    View details for DOI 10.1097/01.blo.0000191317.85422.c3

    View details for Web of Science ID 000233794700015

    View details for PubMedID 16330988

  • Comparison of primary total hip replacements performed with a standard incision or a mini-incision. journal of bone and joint surgery. American volume Woolson, S. T., Mow, C. S., Syquia, J. F., Lannin, J. V., Schurman, D. J. 2004; 86-A (7): 1353-1358

    Abstract

    Primary total hip replacement performed through an incision that is

    View details for PubMedID 15252080

  • Mobile- vs. fixed-bearing total knee arthroplasty - A clinical and radiologic study JOURNAL OF ARTHROPLASTY Woolson, S. T., Northrop, G. D. 2004; 19 (2): 135-140

    Abstract

    A consecutive series of patients undergoing total knee arthroplasty (TKA) using either a mobile-bearing (MB) or a fixed-bearing (FB) implant were studied. Forty-four patients received 57 MB rotating platforms, and 40 patients received 45 FB posterior stabilized implants. At an average 41-month follow-up (range, 2-6 years), no significant differences were found between the groups with respect to Knee Society ratings or pain scores. Postoperative flexion was not different between the groups (116 degrees for MB and 118 degrees for FB). Three MB knees were revised for implant-related complications. There was no difference between these MB or FB knee implants clinically or radiographically at early follow-up. However, more patients with a MB knee required early revision for failure of rotating patellar or tibial polyethylene implants.

    View details for DOI 10.1016/j.arth.2003.10.004

    View details for Web of Science ID 000189119300001

    View details for PubMedID 14973854

  • Letter to the editor. journal of arthroplasty Woolson, S. T. 2004; 19 (1): 132-133

    View details for PubMedID 14716662

  • Preoperative autologous donation for hip replacement. journal of bone and joint surgery. American volume Woolson, S. T. 2003; 85-A (12): 2485-2486

    View details for PubMedID 14668529

  • Autologous blood transfusion after total knee arthroplasty - A randomized, prospective study comparing predonated and postoperative salvage blood JOURNAL OF ARTHROPLASTY Woolson, S. T., Wall, W. W. 2003; 18 (3): 243-249

    Abstract

    A randomized, prospective study of the use of allogeneic blood was performed in a consecutive series of patients who underwent primary total knee arthroplasty (TKA) and had autologous transfusion either from one unit of predonated autologous blood or from postoperative unwashed blood salvage. In this study, 83 patients (88 knees) were included, with 47 knees in the salvage group and 41 in the predonation group. There were no differences between groups in average age, height, and weight, or gender, diagnoses, or anesthesia type. No significant difference was seen between the groups in the prevalence of allogeneic blood transfusion (5% for the predonation group and 0% for salvage group). Postoperative blood salvage was as effective as predonated autologous blood in preventing the risk associated with allogeneic blood after TKA.

    View details for DOI 10.1054/arth.2003.50058

    View details for Web of Science ID 000182605100001

    View details for PubMedID 12728413

  • The effect of partial or full weight bearing ambulation after cementless total hip arthroplasty JOURNAL OF ARTHROPLASTY Woolson, S. T., Adler, N. S. 2002; 17 (7): 820-825

    Abstract

    The clinical and radiographic results of 46 patients who underwent 50 consecutive primary total hip arthroplasties using a fully porous-coated collared femoral component were determined at a minimum of 2 years' follow-up. Twenty-four patients (25 hips) who were allowed to bear full weight immediately postoperatively were compared with a historical control group of 24 patients (25 hips) who were instructed to bear < or =50 lb of weight for 6 weeks. The average Harris hip score for the partial weight bearing group was 95 compared with 97 for the full weight bearing group. All femoral components in both groups had radiographic evidence of bone ingrowth fixation at the final follow-up. When solid initial fixation is obtained intraoperatively and radiographically using a fully porous-coated (AML) femoral component, it seems that bone ingrowth fixation reliably occurs whether or not a partial or full weight-bearing postoperative protocol is followed.

    View details for DOI 10.1054/arth.2002.34809

    View details for Web of Science ID 000178462200002

    View details for PubMedID 12375238

  • Measurement of perioperative flexion-extension mechanics of the knee joint JOURNAL OF ARTHROPLASTY Giori, N. J., Giori, K. L., Woolson, S. T., Goodman, S. B., Lannin, J. V., Schurman, D. J. 2001; 16 (7): 877-881

    Abstract

    Perioperative knee mechanics currently are evaluated Perioperative knee mechanics currently are evaluated by measuring range of motion. This is an incomplete measurement, however, because the torque applied to achieve the motion is not measured. We hypothesized that a custom goniometer and force transducer could measure the torque required to passively flex a knee through its full range of motion. This measurement was done in the operating room immediately before and after surgery in 20 knees having total knee arthroplasty and 9 having surgery on another limb. Surgery changed the mechanics of 8 knees, whereas unoperated knees remained unchanged. This measurement technique is safe, easy, and repeatable. It improves on the current standard of perioperative knee measurement and can be applied to investigate the effects of surgery and rehabilitation on ultimate knee motion.

    View details for Web of Science ID 000171577100010

    View details for PubMedID 11607904

  • Autologous blood and allogeneic transfusion. journal of bone and joint surgery. American volume Woolson, S. T. 2001; 83-A (6): 953-954

    View details for PubMedID 11407805

  • The significance of stem-cement loosening of grit-blasted femoral components ORTHOPEDICS Schmalzried, T. P., Zahiri, C. A., Woolson, S. T. 2000; 23 (11): 1157-1164

    Abstract

    This study analyzed 15 patients who underwent revision for loosening at the stem-cement interface. The femoral components were from the same manufacturer and had grit-blast roughened surfaces. An apparent radiographic deficiency in the cement mantle was present in at least one zone in 1 3 patients. In 9 of 12 patients with localized osteolysis, the osteolysis developed in a zone with an apparent radiographic cement mantle defect. Loosening occurred due to tension failure of the stem-cement interface followed by axial subsidence and movement into relative retroversion. Motion between the stem and the cement mantle fueled an abrasive wear mechanism between the roughened metal surface and the cement mantle, generating excessive metal and cement particles that gained access to endosteal bone via defects in the cement mantle and resulting in localized osteolysis. Although the roughened surface played a central role in these failures, it is unlikely the layer of polymethylmethacrylate (precoat) played a role in the mechanism of failure. In some cases, debonding occurred as a result of tension failure of the metal-precoat interface. In others, tension failure occurred within the cement mantle, leaving the precoat and some cement from the mantle on the stems. There was no difference in the mechanism of failure of stems with precoat proximally compared to stems with precoat proximally and distally. One stem had no precoat; findings in this patient were indistinguishable from the others. The significance of debonding depends on the surface roughness of the stem. Debonding carries a poorer prognosis with a rougher stem surface because of abrasive wear with the generation of numerous metal and cement particulates, which can lead to rapid osteolysis if there are cement mantle defects. Stems with a higher metal-cement bond strength may require a higher quality cement mantle for long-term success.

    View details for Web of Science ID 000165262900008

    View details for PubMedID 11103959

  • Risk factors for dislocation during the first 3 months after primary total hip replacement JOURNAL OF ARTHROPLASTY Woolson, S. T., Rahimtoola, Z. O. 1999; 14 (6): 662-668

    Abstract

    The prevalence of dislocation of a total hip replacement during the first 3 postoperative months was determined for a series of 315 patients who underwent a unilateral primary total hip operation. All operations were performed by 1 surgeon using a standardized posterior approach with a complete capsulectomy. All of the patients had a femoral component made by 1 manufacturer that had the same 28-mm modular head, the same femoral neck diameter, and the same offset for each size implant. One cementless acetabular component was used for all patients. All of the patients followed the same postoperative rehabilitation program. Of 315 patients, 14 sustained a dislocation, resulting in a prevalence of 4%. There were 13 posterior dislocations and 1 anterior dislocation. Because the surgeon, the surgical approach, the femoral component design, and the rehabilitation protocol were identical for all of these patients, the only variables that could affect the risk of dislocation were the size of the acetabular component and the femoral neck length, the type of fixation of the femoral component, the orientation of the acetabular component, and the characteristics of each patient. The patient characteristics that were studied included age; gender; height; weight; preoperative diagnosis; and a category termed cerebral dysfunction, which included a state of confusion during the hospital stay, a prior history of excessive alcohol consumption, or both of these conditions. Statistical analysis demonstrated 1 variable that was associated with a higher dislocation rate, the presence of cerebral dysfunction. There was a trend toward increased age as a risk factor. None of the other patient or component variables were found to be significant risk factors.

    View details for Web of Science ID 000082615200004

    View details for PubMedID 10512436

  • Results of a method of leg-length equalization for patients undergoing primary total hip replacement JOURNAL OF ARTHROPLASTY Woolson, S. T., Hartford, J. M., Sawyer, A. 1999; 14 (2): 159-164

    Abstract

    The postoperative leg-length discrepancy was determined radiographically for a consecutive series of 351 patients (408 hips) who underwent bilateral or unilateral primary total hip replacement using a single method of leg-length equalization by preoperative planning with overlay templates. The method of equalization was performed by a measurement of the femoral head and neck segment to be resected from a reference point at the superior aspect of the dislocated femoral head. The amount of femoral bone resected was determined preoperatively by determining the dimensions of the acetabular component thickness and the femoral component head and neck height that would be replacing this resected bone and adjusting this distance for any preexisting leg-length discrepancy. Using this leg-length equalization method, the length of the modular femoral head neck was chosen preoperatively, rather than using soft tissue tension across the prosthetic hip joint to determine whether the leg lengths were equal. Postoperative leg lengths were determined radiologically from a measurement from the acetabular teardrop to the lesser trochanter. Ninety-seven percent of the patients had a postoperative leg-length discrepancy that was less than 1 cm, and 86% had a leg-length difference that was 6 mm (1/4 inch) or less. The average postoperative discrepancy for these 351 patients was 1 mm.

    View details for Web of Science ID 000078596400006

    View details for PubMedID 10065720

  • Deep venous thrombosis prophylaxis for knee replacement: warfarin and pneumatic compression. American journal of orthopedics (Belle Mead, N.J.) Woolson, S. T., Robinson, R. K., Khan, N. Q., Roqers, B. S., Maloney, W. J. 1998; 27 (4): 299-304

    Abstract

    A prospective study of the prevalence of proximal deep venous thrombosis in total knee replacement patients who had prophylaxis for thrombosis with a combination of low-dose warfarin and intermittent pneumatic compression was done. Two hundred and ninety-seven patients who underwent 377 consecutive total knee replacements were studied. All patients were treated with low-dose warfarin and intermittent pneumatic compression using thigh-high sleeves. Surveillance for proximal thrombosis was done by duplex ultrasonography. Proximal thrombosis was detected in 19 patients, for a prevalence of 5%. There were 3 patients who had a major bleeding complication, for a prevalence of 0.9% for the 337 procedures performed. Although there was no concurrent control group of patients treated with another means of prophylaxis to compare with these patients, the low prevalence of proximal thrombosis and the low risk of major bleeding complications that was found compares well with recent reports on the effectiveness and safety of low-molecular-weight heparin.

    View details for PubMedID 9586729

  • Factor V Leiden and the risk of proximal venous thrombosis after total hip arthroplasty JOURNAL OF ARTHROPLASTY Woolson, S. T., Zehnder, J. L., Maloney, W. J. 1998; 13 (2): 207-210

    Abstract

    Deep vein thrombosis (DVT) remains a major cause of morbidity in patients undergoing total hip arthroplasty (THA). Despite postoperative DVT prophylaxis, 20-50% of THA patients still develop DVT. Currently, there is no accurate way of predicting which patients will develop DVT despite standard prophylaxis. The presence of factor V Leiden is the most common cause of inherited DVT risk. It has been postulated that patients who have factor V Leiden and are subjected to thrombogenic stressors such as THA would have an increased risk of thrombosis. The factor V Leiden genotype of 36 patients who developed proximal DVT after surgery and 45 control patients who had THA but did not develop DVT was determined. All patients had had prophylaxis against thrombosis using intermittent pneumatic compression alone or in combination with warfarin or aspirin. Surveillance for proximal DVT was performed on all patients prior to discharge by duplex ultrasound. The 2 groups were similar in age, sex, and type of operation. Three of 36 study patients who had developed DVT (8%) and 2 of 45 control patients who had not developed DVT (4%) were heterozygotes for factor V Leiden; these prevalences were not statistically different. Heterozygosity for factor V Leiden is not associated with DVT prophylaxis failure in patients undergoing THA.

    View details for Web of Science ID 000072498700014

    View details for PubMedID 9526216

  • Referral patterns of hip pain in patients undergoing total hip replacement ORTHOPEDICS Khan, N. Q., Woolson, S. T. 1998; 21 (2): 123-126

    Abstract

    This study was undertaken to determine the most common referral patterns of hip pain in patients scheduled to undergo primary and revision total hip replacement. The exact location of pain from the hip was recorded prospectively for 323 patients (358 hips) who had primary total hip replacement and for 94 patients who had revision of a loose total hip. Seventy-three percent of patients with primary hip disease had pain in the groin, and 27% had groin pain that referred to the knee. Eighty-nine percent of 57 patients who had femoral component loosening had thigh or knee pain, and all of the 34 patients who had a loose acetabular component with a well-fixed femoral implant had pain in the hip region without distal radiation of pain. These results indicate that in patients who have a painful total hip, thigh pain is highly suggestive of femoral component loosening and pain located around the hip region that does not radiate distally is associated with isolated acetabular component loosening.

    View details for Web of Science ID 000072881600002

    View details for PubMedID 9507264

  • Fatigue fracture of a forged cobalt-chromium-molybdenum femoral component inserted with cement. A report of ten cases. journal of bone and joint surgery. American volume Woolson, S. T., Milbauer, J. P., Bobyn, J. D., Yue, S., Maloney, W. J. 1997; 79 (12): 1842-1848

    Abstract

    Ten patients who had had a total hip replacement with a forged cobalt-chromium-molybdenum femoral prosthesis (Precoat or Precoat Plus) inserted with cement were seen with a fatigue fracture of the stem an average of fifty months (range, nineteen to seventy-four months) postoperatively. The average age of the patients was sixty-one years (range, forty-three to seventy-three years), and the average weight was ninety-six kilograms (range, seventy to 130 kilograms). Eight patients had had a primary total hip replacement, and two had had a revision; all of the acetabular components had been inserted without cement. Radiographs that had been made before the fracture were available for four of the eight hips that had had a primary replacement; all four had radiographic evidence of debonding of the cement mantle from the proximal end of the stem. This probably caused exaggerated cantilever bending stresses on the proximal aspect of the stem as the distal end of the stem was well fixed. The radiographs of both hips that had had a revision demonstrated a non-union of the greater trochanter, which had resulted in separation at the cement-bone interface at the proximal portion of the femur before the fracture. Scanning electron micrographs of five of the ten fractured prostheses demonstrated a fatigue fracture that began near the anterolateral corner of the prosthesis, through characters that had been etched on the implant with a laser. Metallurgical analysis indicated subsurface voids or inclusions, or both, immediately under the region that had been etched. This finding is consistent with thermal changes to the microstructure of the alloy that probably caused a focal reduction in the material strength. A high proportion (seven) of the ten stems had a poor cement mantle. Also, of the seven small stems that were used, six had been implanted in patients who weighed more than eighty kilograms, so there was relative undersizing of the prostheses. Early debonding of the proximal end of a Precoat femoral prosthesis from the cement mantle may occur as a result of a thin cement mantle, leading to loosening and possibly to early fatigue fracture of the stem if the distal portion of the stem remains solidly fixed in the distal portion of the cement column. On the basis of our experience, we recommend that patients who have radiographic evidence of a debonded Precoat femoral component should be informed of the risk of fatigue fracture of the stem and be followed closely even though there may be no symptoms of loosening of the femoral component.

    View details for PubMedID 9409798

  • Intermittent pneumatic compression prophylaxis for proximal deep venous thrombosis after total hip replacement. journal of bone and joint surgery. American volume Woolson, S. T. 1996; 78 (11): 1735-1740

    Abstract

    The efficacy of intermittent pneumatic compression in the prevention of proximal deep venous thrombosis was determined in a consecutive series of patients who had primary or revision total hip replacement. Two hundred and eighty-nine patients (242 primary and eighty revision hip replacements) who were at least forty years old were managed intraoperatively and postoperatively with intermittent pneumatic compression with use of thigh-high sequential compression sleeves and thigh-high elastic compression stockings as the only form of prophylaxis. Venous ultrasonography of the ipsilateral lower extremity was performed, at an average of five days postoperatively, to determine the presence of a thrombus in the femoral and popliteal veins. The prevalence of proximal deep venous thrombosis was 6 per cent (twenty of 322 procedures), and no patient had a clinically detected pulmonary embolism. The prevalence of a proximal thrombus was 4 per cent (ten of 233 procedures) when a regional anesthetic had been used and 11 per cent (ten of eighty-nine procedures) when a general anesthetic had been used; this difference was significant (p = 0.02). The prevalence of a proximal thrombus was 3 per cent (eight of 245 procedures) for patients who were less than seventy-five years old and 16 per cent (twelve of seventy-seven procedures) for patients who were seventy-five years old or more (p < 0.0001). No patient had a major bleeding complication. Twenty-nine other patients who had an additional risk factor for thrombosis, such as a history of deep venous thrombosis, were managed with intermittent pneumatic compression and low-dose warfarin. The prevalence of proximal deep venous thrombosis in this group of patients was 19 per cent (six of thirty-one procedures). Intraoperative and postoperative intermittent pneumatic compression, combined with the use of a regional anesthetic, was found to be highly effective in the prevention of proximal deep venous thrombosis after total hip replacement. Despite the limitations inherent in comparisons among series, it is noteworthy that the prevalence of proximal thrombosis in our series was similar to the reported prevalences in several large series of patients who had a total hip replacement and were managed with either low-dose warfarin or low-molecular-weight heparin. However, there was no risk of major postoperative bleeding in the current study.

    View details for PubMedID 8934490

  • Acetabular revision using a bone-ingrowth total hip component in patients who have acetabular bone stock deficiency JOURNAL OF ARTHROPLASTY Woolson, S. T., Adamson, G. J. 1996; 11 (6): 661-667

    Abstract

    The clinical and radiologic results of acetabular revision using a porous titanium-mesh metal-backed acetabular component fixed to the pelvis with screws were studied in 30 consecutive patients (32 hips) who had moderate or severe acetabular bone loss. All of the acetabula were classified as type III or IV according to the American Association of Orthopaedic Surgeons' acetabular grading system. Particulate autologous or allogenic bone-graft was used in 75% of the reconstructions. The mean follow-up period was 69 months (range, 46-109 months). Three acetabular components (9%) were rerevised for aseptic loosening at an average of 64 months, including one patient who had a primary diagnosis of radiation necrosis of the ilium. The average Harris hip score for the remaining 29 hips rose from 46 to 81. The radiologic failure rate was 3% (1 of 29 unrevised hips) for a total failure rate of 12%. No pelvic osteolysis was seen with this implant. Revision of acetabula that have moderate or severe bone deficiency by a bone-ingrowth acetabular component fixed with screws and bone-graft appears to be successful in restoring bone stock and providing a stable, pain-free reconstruction.

    View details for Web of Science ID A1996VJ48500003

    View details for PubMedID 8884440

  • Porous pad separation and loosening of Harris-Galante femoral hip components JOURNAL OF ARTHROPLASTY Woolson, S. T., Comstock, C. G. 1996; 11 (4): 474-477

    Abstract

    Failure of the bond between the metal beads and the solid substrate of porous-coated chrome-cobalt femoral components, or so-called "bead shedding," has been reported previously and may indicate motion of the component within the femur or mechanical loosening of the prosthesis. Failure of the bond between a sintered titanium fibermesh pad and a titanium alloy femoral stem has not been documented in the literature to date. The separation of fibermesh pads from three Harris-Galante femoral prostheses (Zimmer, Warsaw, IN) is reported.

    View details for Web of Science ID A1996UR83000017

    View details for PubMedID 8792256

  • Primary total hip replacement with insertion of an acetabular component without cement and a femoral component with cement. Follow-up study at an average of six years. journal of bone and joint surgery. American volume Woolson, S. T., Haber, D. F. 1996; 78 (5): 698-705

    Abstract

    We performed a retrospective study of a consecutive series of patients who had had a primary total hip replacement with so-called hybrid fixation of the components (an acetabular component inserted without cement and a femoral component inserted with cement) between September 1985 and June 1989. Clinical data were available for 114 patients (125 hips), of whom 110 (121 hips) also had radiographic data. The minimum duration of follow-up was fifty-six months or until revision, and the average duration was seventy-two months. The average Harris hip score improved from 47 points preoperatively to 91 points postoperatively (for the 109 patients who did not have subsequent revision of the femoral component). Only three patients who did not have a revision had more than slight pain in the hip. Four hips (3 percent) were revised for aseptic loosening of the femoral component at an average of fifty-five months; two of these four had a fracture of the femoral component. One patient had resection arthroplasty for late infection. One patient had disassembly of an acetabular polyethylene liner, and another had dissociation of a modular femoral head; both patients had a reoperation. Radiographically, two femoral components were definitely loose, as determined by subsidence of the component in one patient and a fracture of the cement in the other. Ten hips (8 percent) had endosteal lysis of the femur. Over-all, 5 percent (six) of 121 femoral components were either revised for loosening or had definite radiographic evidence of loosening, but no acetabular component was loose. The clinical results in the 104 patients (115 hips) for whom clinical and radiographic data were available were excellent at the time of intermediate follow-up. Since few hips had progressive radiolucent lines about the acetabular of femoral component, we are optimistic that the long-term results will also be satisfactory.

    View details for PubMedID 8642026

  • Increasing incidence of femoral osteolysis in association with uncemented Harris-Galante total hip arthroplasty - A follow-up report JOURNAL OF ARTHROPLASTY Maloney, W. J., Woolson, S. T. 1996; 11 (2): 130-134

    Abstract

    Sixty-nine consecutive uncemented total hip arthroplasties were performed in 59 patients using the Harris-Galante prosthesis (Zimmer, Warsaw, IN). The patients were reviewed an average of 44 and 71 months after surgery. Patients in whom femoral osteolysis was identified at the time of the first review were again evaluated at the second review to determine if the size of the osteolytic lesion had increased over time. At the initial review an average of 44 months postsurgery, the overall incidence of femoral osteolysis was 22%. At the second review, the incidence of femoral osteolysis had increased from 22 to 52%. Two thirds of the lytic lesions diagnosed at the time of the first review had increased in size. This study demonstrated that the incidence of femoral osteolysis in cementless hip arthroplasties increases with time and that the majority of existing lesions enlarge over time. Once lesions are identified, more frequent follow-up evaluations are recommended. Revision surgery may be required for progressive femoral osteolysis, despite the absence of significant clinical symptoms.

    View details for Web of Science ID A1996TX39900005

    View details for PubMedID 8648304

  • Failure of a proximally porous-coated femoral prosthesis in revision total hip arthroplasty JOURNAL OF ARTHROPLASTY Woolson, S. T., DELANEY, T. J. 1995; 10: S22-S28

    Abstract

    A retrospective study was done on a consecutive series of patients who had revision of a femoral hip prosthesis using a titanium-alloy implant with proximal fibermesh pads. Of 28 patients who had revision using a Harris-Galante (Zimmer, Warsaw, IN) femoral prosthesis between 1985 and 1989, 25 of them (25 hip arthroplasties) were followed for an average of 5.5 years (range, 4-8 years); the other 3 had died. There were 12 men and 13 women whose age averaged 55 years. Thirty-two percent of the patients had moderate or severe femoral bone stock deficiency before surgery and 72% had intramedullary femoral bone-grafting. All of the patients had revision of the acetabular component using a cementless Harris-Galante prosthesis. Five (20%) of the 25 patients have undergone repeat femoral revision, 4 for aseptic loosening and 1 for persistent thigh pain. Of the 20 hips that have not been revised, 9 (45%) of the femoral prostheses have subsided 5 mm or more. Femoral endosteal lysis was present in 36% of all the hips. Only 8 (32%) of the 25 patients had radiologic signs of bone ingrowth fixation of the femoral component. The average Harris hip score rose from 46 before surgery for all 25 patients to 82 (range, 55-100) at last follow-up examination for the 20 patients not rerevised. Because of the poor clinical results (36% of patients with a poor Harris hip score [4 patients] or rerevised [5 patients]) and radiologic results (48% subsidence) of femoral reconstruction with this proximally porous-coated femoral prosthesis, its use for revision hip surgery is not recommended.

    View details for Web of Science ID A1995TM16400004

    View details for PubMedID 8776052

  • WEAR OF THE POLYETHYLENE OF HARRIS-GALANTE ACETABULAR COMPONENTS INSERTED WITHOUT CEMENT JOURNAL OF BONE AND JOINT SURGERY-AMERICAN VOLUME Woolson, S. T., Murphy, M. G. 1995; 77 (9): 1311-1314

    Abstract

    The amount and rate of linear wear of the polyethylene of eighty Harris-Galante acetabular components, implanted without cement during a primary or revision total hip replacement in seventy-two patients, were determined by a comparison of the thicknesses of the cup as measured on the initial and most recent follow-up radiographs. The measurements were corrected for magnification error by direct measurement of the diameter of the femoral head on each radiograph. The mean duration of follow-up was sixty-eight months (range, fifty-six to ninety-six months). Linear wear averaged 0.77 +/- 0.51 millimeter (range, zero to 1.83 millimeters) over-all, with a mean rate of 0.14 +/- 0.09 millimeter (range, zero to 0.35 millimeter) per year. An increased rate of wear per year correlated with a decreased age of the patient and with regular exercise, but there was no relationship with the weight or sex of the patient, the initial thickness of the polyethylene, or the angle of abduction of the cup.

    View details for Web of Science ID A1995RV56800003

    View details for PubMedID 7673278

  • THE RESOLUTION OF DEEP VENOUS THROMBOSIS THAT OCCURS AFTER TOTAL JOINT ARTHROPLASTY - A STUDY OF THROMBI TREATED WITH ANTICOAGULATION AND OBSERVED BY REPEAT VENOUS ULTRASOUND SCANS CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Woolson, S. T. 1994: 86-91

    Abstract

    Thrombi found in the deep thigh veins of postoperative total hip or knee arthroplasty patients were followed prospectively by repeat venous ultrasonography to determine the efficacy and appropriate duration of anticoagulation therapy. Forty-four patients who had 47 proximal vein thrombi (femoral or popliteal) were treated with heparin or warfarin or both. Thirteen patients had two or more and 34 had a single follow-up venous ultrasound scan. The last follow-up scan was done at an average of seven weeks after the thrombus was diagnosed. Thirty-four thrombi (72%) had lysed at that time. Twelve thrombi (26%) were smaller or unchanged in size. One thrombus propagated and later embolized despite the use of heparin and warfarin. Forty-five percent (21 of 47) of the thrombi had lysed within six weeks of the initiation of anticoagulation therapy. The results of this study indicate that the standard duration of anticoagulation therapy for postoperative proximal deep vein thrombosis of three months may be excessively long for half of these patients. The use of follow-up venous ultrasound scanning to determine when it is appropriate to terminate anticoagulation therapy is a logical clinical management strategy.

    View details for Web of Science ID A1994MV69000012

    View details for PubMedID 8119042

  • USE OF PREOPERATIVELY DEPOSITED AUTOLOGOUS BLOOD FOR TOTAL KNEE REPLACEMENT ORTHOPEDICS Woolson, S. T., Pottorff, G. 1993; 16 (2): 137-142

    Abstract

    The efficacy of obviating homologous blood transfusion by an autologous blood program was investigated prospectively in a series of patients undergoing total knee replacement. Seventy-nine patients who underwent 110 consecutive total knee replacement operations (66 unilateral and 22 one-stage bilateral procedures) from 1986 to 1990 were studied. All patients who had elective procedures (86 of the 88 procedures) were encouraged to donate autologous blood prior to surgery if there were no medical contraindications. Seventy-six percent of the elective procedures (65 of 86) were done in patients who deposited autologous blood preoperatively. Homologous transfusion was required after only two of these 65 procedures (3%) in patients who predeposited autologous blood. This frequency of homologous transfusion was an order of magnitude lower than the frequency of homologous transfusion (35%) after procedures in patients who did not predeposit blood. Overall, 89% of the entire series of 88 procedures were performed in patients who received only autologous blood and 94% of the total volume of blood given after these 88 procedures was autologous. The Cell Saver was successful in salvaging an average of 287 mL of red blood cells per procedure after 36 procedures, but was not successful in saving blood after 29 others. The authors conclude that preoperatively deposited autologous blood is effective in reducing the need for homologous transfusion to patients who undergo elective total knee replacement.

    View details for Web of Science ID A1993KL76600004

    View details for PubMedID 8441713

  • Piriformis tendon repair failure after total hip replacement. Orthopaedic review Kao, J. T., Woolson, S. T. 1992; 21 (2): 171-174

    Abstract

    Posterior hip dislocation is a common complication after total hip replacement. Some authors recommend repair of the short external rotator tendons to stabilize the hip joint postoperatively. We evaluated the efficacy of repair of the piriformis tendon in 10 consecutive total hip replacement cases. Eight of the 10 repairs failed during the early postoperative period, and one of the two repairs that did not fail was in the only patient to sustain a posterior dislocation. We believe that repair of the piriformis tendon is of no significant benefit to the stability of a total hip replacement joint.

    View details for PubMedID 1538884

  • Cementless total hip arthroplasty using a porous-coated prosthesis for bone ingrowth fixation. 3 1/2-year follow-up. journal of arthroplasty Woolson, S. T., Maloney, W. J. 1992; 7: 381-388

    Abstract

    The clinical and radiologic results of a consecutive series of 59 patients (69 hips) who had primary total hip arthroplasty using cementless prostheses was studied. Harris-Galante acetabular and femoral prostheses, which have a porous fiber-metal mesh coating intended to encourage bone ingrowth fixation, were used in all cases. Two femoral components were revised during the follow-up period, one for aseptic loosening and the other for late septic loosening. In the remaining 67 hips, the average Harris hip score rose from a preoperative 52 to 94 at the last follow-up examination (average follow-up period, 44 months). Eighty-eight percent of these hips had an excellent result (Harris hip score of 90 or more). Radiologic analysis demonstrated that all the acetabular components were stable. Eighty-three percent of the femoral components appeared to have stable bone ingrowth fixation, five components (7%) had stable fibrous ingrowth, and seven (10%) were unstable. Parallel radiodense lines were seen around the smooth portion of the stem in 93% of hips, but this finding appeared to have no clinical importance. Significant stress shielding of the proximal femur was seen in 16% of hips. Endosteal lysis of the distal femur occurred in 22% of hips, including large lesions in two patients who will require future revision surgery because of femoral diaphysis weakening. Femoral lysis was not associated with hip or thigh pain and was most common in young, male patients who had high activity levels.(ABSTRACT TRUNCATED AT 250 WORDS)

    View details for PubMedID 1431920

  • Perioperative blood loss associated with total knee arthroplasty. A comparison of procedures performed with and without cement. journal of bone and joint surgery. American volume Woolson, S. T. 1991; 73 (10): 1574-?

    View details for PubMedID 1748706

  • Intermittent pneumatic compression to prevent proximal deep venous thrombosis during and after total hip replacement. A prospective, randomized study of compression alone, compression and aspirin, and compression and low-dose warfarin. journal of bone and joint surgery. American volume Woolson, S. T., Watt, J. M. 1991; 73 (4): 507-512

    Abstract

    A prospective, randomized study of the effectiveness of intraoperative and postoperative use of intermittent pneumatic compression, alone or in combination with oral administration of either aspirin or low-dose warfarin, was done of a consecutive series of patients who had a total hip replacement and were more than thirty-nine years old. All patients began walking by the third postoperative day. One hundred and ninety-six patients who had 217 total hip arthroplasties were included. Twenty-eight per cent of the procedures were revisions of a previous total hip replacement or of an endoprosthesis, and the remainder were primary arthroplasties. Patients were randomized as to the type of prophylaxis that they received: intermittent pneumatic compression alone, seventy-six hips; intermittent pneumatic compression and aspirin, seventy-two hips; or intermittent pneumatic compression and low-dose warfarin, sixty-nine hips. Before discharge from the hospital, and at an average of seven days after the operation, all patients were evaluated for the presence of proximal deep-vein thrombosis with either venography on the side of the operation or with bilateral venous ultrasonography. The relative frequency with which thrombosis occurred in a proximal vein was not significantly different in the three groups; the over-all relative frequency was 10 per cent. Intermittent compression during and after the operation effectively reduces the rate of proximal-vein thrombosis after total hip replacement. With the number of patients in our study, the effectiveness of this technique could not be shown to be augmented by oral administration of either aspirin or low-dose warfarin.

    View details for PubMedID 2013589

  • Use of autologous blood in total hip replacement. A comprehensive program. journal of bone and joint surgery. American volume Woolson, S. T., Watt, J. M. 1991; 73 (1): 76-80

    Abstract

    We evaluated the effectiveness of a comprehensive program for the use of autologous blood in reduction of the need for transfusion of homologous blood in total hip replacement in a prospective study of a consecutive series of patients. Transfusion of homologous blood was minimized through transfusion of preoperatively deposited autologous blood, intraoperative and postoperative salvage of washed red blood cells, and use of the clinical condition of the patient as the sole criterion for transfusion of non-autologous blood, regardless of the hematocrit. The cases of 143 patients who had had 154 primary total hip replacements were studied. One hundred and forty-three procedures were done on patients who had not been prevented from donating blood for medical reasons, and 93 per cent of these 143 procedures were performed with the availability of one to five units of preoperatively deposited autologous blood. The patients predeposited an average of 2.6 units of blood for each procedure. Ninety-two per cent of the procedures for which autologous blood had been predeposited were performed without transfusion of homologous blood. In the entire group of patients, almost 90 per cent of the transfused blood was autologous blood. Intraoperative salvage of red blood cells was successful in 148 procedures, and salvage was continued in the recovery room for all of these patients. An average of 408 milliliters of red blood cells was saved and reinfused, and this was 28 per cent of the average total loss of blood (1435 milliliters) for this series of procedures.(ABSTRACT TRUNCATED AT 250 WORDS)

    View details for PubMedID 1985997

  • CLINICIAN-DIRECTED HOSPITAL COST MANAGEMENT FOR TOTAL HIP-ARTHROPLASTY PATIENTS CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Sommers, L. S., Schurman, D. J., Jamison, J. Q., Woolson, S. T., ROBISON, B. L., Silverman, J. F. 1990: 168-175

    Abstract

    Can patients treated with total hip arthroplasty (THA) receive high-quality inpatient care at less cost? In 1984, a group of orthopedic surgeons and nurses examined the use of resources for THA patients and changed certain clinical practices to promote more cost-effective hospital care. At the end of the two-year project, orders for complete blood counts fell 72% and mean operating room time dropped 47 minutes for the participating orthopedists. For all orthopedists in the division, average length of stay (ALOS) decreased from 13 to 11 days. By the end of the following year, when clinicians received quarterly length-of-stay (LOS) data, ALOS dropped further to 9.8 days. This significant ALOS reduction was not accompanied by an increase in hospital readmissions or nursing home placements. The ALOS reduction was also not seen in elective coronary artery bypass graft patients whose ALOS did not substantially change over the same period. Two years after the project, ALOS for THA patients remained at ten days or below. This reduction in LOS and in the use of other hospital services translated into a mean total hospital charge decrease of $2045 per THA patient.

    View details for Web of Science ID A1990DX99200021

    View details for PubMedID 2394045

  • B-mode ultrasound scanning in the detection of proximal venous thrombosis after total hip replacement. journal of bone and joint surgery. American volume Woolson, S. T., MCCRORY, D. W., Walter, J. F., Maloney, W. J., Watt, J. M., CAHILL, P. D. 1990; 72 (7): 983-987

    Abstract

    A prospective study of the accuracy of real-time B-mode ultrasonography in detecting deep venous thrombosis in the femoral and popliteal veins of the lower extremity was conducted on a consecutive series of patients who had had a total hip replacement. Ascending venography was used as a diagnostic standard. One hundred and forty-three patients had ultrasound studies of both lower extremities and a venographic study of the operatively treated lower extremity at an average of 7.6 days postoperatively. The two tests were done within twenty-four hours of each other. Both ultrasonography and venography were done on 152 extremities. Two paired studies were excluded from the analysis of results because the ultrasound scans could not be interpreted. In 131 extremities, both diagnostic tests were negative for proximal thrombosis. Eight extremities had isolated thrombosis of a vein in the calf that was detected only by venography. In nineteen extremities, old or fresh thrombosis was diagnosed by venography. In four extremities, an old thrombosis of the superficial femoral vein was detected by both studies. In four of the extremities that had a new thrombus in the common femoral vein and in nine that had a new thrombus in the superficial femoral vein, abnormal findings on ultrasound scans correlated with those on venograms. There were two false-negative ultrasound scans and one false-negative venogram. The sensitivity, specificity, and accuracy of ultrasonography were 89, 100, and 99 per cent for the diagnosis of thrombosis of the proximal veins of the lower limb and 63, 100, and 93 per cent for the diagnosis of thrombosis when the entire venous system of the limb was included.(ABSTRACT TRUNCATED AT 250 WORDS)

    View details for PubMedID 2200790

  • Disassembly of a modular femoral prosthesis after dislocation of the femoral component. A case report. journal of bone and joint surgery. American volume Woolson, S. T., POTTORFF, G. T. 1990; 72 (4): 624-625

    View details for PubMedID 2324151

  • LEG LENGTH EQUALIZATION DURING TOTAL HIP-REPLACEMENT ORTHOPEDICS Woolson, S. T. 1990; 13 (1): 17-21

    Abstract

    A method of equalization of leg lengths during total hip replacement surgery was developed which utilizes the concept of equalizing the vertical dimensions of the resected femoral head and neck segment and the remaining hip joint cartilage space, which are removed during the procedure, with the vertical dimensions of the femoral and acetabular prostheses, which are implanted into that void. This was accomplished by determining the dimensions of the prostheses from careful preoperative templating technique and by using a simple arithmetic formula to determine the level of the femoral neck osteotomy. The level of the osteotomy was made by a measurement from the top of the dislocated head of the femur to the medial femoral neck calcar. The radiologic postoperative leg length differences of a consecutive series of 84 patients undergoing primary total hip replacement using this method were determined. The average discrepancy was 2.8 mm. Seventy-five patients (89%) were found to have a postoperative leg length discrepancy of 6 mm (1/4 inch) or less. Six patients (7%) had a discrepancy of 7 to 13 mm, and only three patients (4%) had more than 13 mm (1/2 inch) leg length difference. Using this technique only two patients (2.5%) with unilateral hip replacements had leg lengthening of more than 6 mm.

    View details for Web of Science ID A1990CK89400002

    View details for PubMedID 2300514

  • External iliac arteriovenous fistula following total hip arthroplasty. A case report. journal of arthroplasty Woolson, S. T., Maloney, W. J., Tanner, J. B. 1989; 4 (3): 281-284

    Abstract

    An external iliac arteriovenous fistula developed 3 years after revision of the acetabular component of a total hip arthroplasty in a patient with rheumatoid arthritis. The mechanism of this complication, which also produced disseminated intravascular coagulopathy, was chronic erosion of the iliac artery from a large bolus of bone cement and/or the protrusio shell that were used to reconstruct a severe acetabular protrusio. Care must be taken to avoid intrapelvic intrusion of hardware or cement during acetabular reconstruction to avoid immediate and late injury to the iliac vessels.

    View details for PubMedID 2795035

  • A CLINICAL PATHOLOGIC BIOCHEMICAL-STUDY OF THE MEMBRANE SURROUNDING LOOSENED AND NONLOOSENED TOTAL HIP ARTHROPLASTIES CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Goodman, S. B., CHIN, R. C., Chiou, S. S., Schurman, D. J., Woolson, S. T., MASADA, M. P. 1989: 182-187

    Abstract

    The clinical and roentgenologic data from 31 excised components from 19 revision arthroplasty cases were correlated with the histology and biochemistry of the membrane at the bone-cement or bone-prosthesis interface. Twenty-seven components were cemented and four were uncemented. Twenty-four implants were clinically and roentgenologically loose, one was possibly loose, and six were well fixed. Loose components, whether cemented or not, demonstrated statistically higher prostaglandin E2 levels in the surrounding membrane compared to the nonloose group. Collagenase and M-collagenase levels were absent or insignificantly low in all specimens; no detectable interleukin 1 beta was found. This suggests that prostaglandin E2 may be associated with the bone lysis associated with prosthesis loosening.

    View details for Web of Science ID A1989AG08900017

    View details for PubMedID 2545398

  • POSTOPERATIVE BLOOD SALVAGE USING THE CELL SAVER AFTER TOTAL JOINT ARTHROPLASTY JOURNAL OF BONE AND JOINT SURGERY-AMERICAN VOLUME SEMKIW, L. B., Schurman, D. J., Goodman, S. B., Woolson, S. T. 1989; 71A (6): 823-827

    Abstract

    The purpose of this study was to investigate whether the salvage in the recovery room of blood from the drainage tubes of patients who had total joint arthroplasty was both feasible and efficacious. The cases of seventy-four patients who had seventy-six consecutive total hip or knee arthroplasties were studied prospectively. Intraoperative salvage of blood was performed using the Cell Saver. After closure of the fascial layer or joint capsule, the drainage tubes were connected to the Cell Saver in the operating room and remained connected in the recovery room for a mean of 2.9 hours. Blood that was collected in the recovery room was then processed and transfused back to the patient. The average amount of blood that was salvaged after different types of arthroplasty varied. The addition of bone cement to the acetabular side during primary total hip replacement decreased the amount of postoperative bleeding and of salvaged blood (p = 0.018), whereas cementing the femoral component had no statistically significant effect. Revision total hip replacement also resulted in more bleeding and in the collection of more blood in the recovery room than did primary total hip replacement (p = 0.03), especially if cement was not used (p less than 0.001). There were no statistical differences in the amount of blood that was collected in the recovery room after unilateral, bilateral, primary, or revision total knee replacement.(ABSTRACT TRUNCATED AT 250 WORDS)

    View details for Web of Science ID A1989AG26400004

  • SUPERFICIAL FEMORAL PSEUDOANEURYSM AND ARTERIAL THROMBOEMBOLISM CAUSED BY AN OSTEOCHONDROMA JOURNAL OF PEDIATRIC ORTHOPAEDICS Woolson, S. T., Maloney, W. J., James, D. R. 1989; 9 (3): 335-337

    Abstract

    A 13-year-old boy with a symptomatic distal femoral osteochondroma was found to have a pseudoaneurysm of the superficial femoral artery caused by the tumor and occlusion of the anterior tibial artery due to arterial thromboembolism. Excision of the exostosis followed by saphenous vein grafting resulted in an excellent clinical recovery.

    View details for Web of Science ID A1989U380200014

    View details for PubMedID 2723054

  • TOTAL JOINT ARTHROPLASTY FOR STEROID-INDUCED OSTEONECROSIS IN CARDIAC TRANSPLANT PATIENTS CLINICAL ORTHOPAEDICS AND RELATED RESEARCH ISONO, S. S., Woolson, S. T., Schurman, D. J. 1987: 201-208

    Abstract

    Ten cardiac transplant patients have had bilateral total hip or knee surgery for treatment of osteonecrosis secondary to corticosteroid immunosuppression. Nine had bilateral total hip arthroplasty and one had bilateral total knee arthroplasty for osteonecrosis of the tibial plateaus. The only immediate postoperative complication was in a single hip patient who had a nonfatal pulmonary embolism. Two patients died from cardiovascular causes; the remaining eight had excellent results from arthroplasty, with an average Harris hip rating of 95 at a mean follow-up period of 34 months. No patient had required revision surgery and radiographic follow-up examination has revealed no evidence of loosening of any of these cemented arthroplasties. One patient developed a late hematogeneous sepsis of one hip seven years after replacement from atypical mycobacterium three months following renal transplantation, which was done 11 years after cardiac transplantation. Total joint arthroplasty has resulted in excellent clinical and radiologic results in this patient population. Despite the increased risks of major surgery in these immunocompromised transplant recipients, total joint arthroplasty appears to be a safe and effective method of treatment of osteonecrosis of the hip.

    View details for Web of Science ID A1987G726000018

    View details for PubMedID 3549092

  • Transfusion of previously deposited autologous blood for patients undergoing hip-replacement surgery. journal of bone and joint surgery. American volume Woolson, S. T., Marsh, J. S., Tanner, J. B. 1987; 69 (3): 325-328

    Abstract

    The efficacy of a program of transfusion of previously deposited autologous blood for patients undergoing total hip-replacement surgery was studied by comparing five different parameters for a group of fifty consecutive patients who deposited blood for autologous transfusion and a randomly chosen, closely matched control group of fifty patients who received only homologous blood. Sixty-two per cent of the patients in the group that deposited autologous blood did not receive additional homologous blood while in the hospital. The patients who deposited autologous blood had a mean preoperative hematocrit of 36 per cent, compared with 39 per cent for the control group, but the average postoperative hematocrits of the two groups did not differ (33 per cent). There was no significant difference in the average total loss of blood or need for replacement of blood between the groups. Transfusion-related complications developed in two patients in the control group. We concluded that previous deposit of autologous blood for transfusion is an effective method for reducing the need for transfusion of homologous blood and for avoiding the attendant complications of transfusion of homologous blood. This method of the replacement of blood should be considered for patients who are to undergo a major orthopaedic procedure on the hip.

    View details for PubMedID 3818698

  • GREENFIELD VENA-CAVAL FILTER FOR MANAGEMENT OF SELECTED CASES OF VENOUS THROMBOEMBOLIC DISEASE FOLLOWING HIP-SURGERY - A REPORT OF 5 CASES CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Woolson, S. T., Harris, W. H. 1986: 201-206

    Abstract

    The use of the Greenfield vena caval filter for thromboembolic disease following major hip surgery is an important part of the orthopedist's armamentarium for treatment of complications or contraindications to standard anticoagulation therapy. The authors report five cases in which a Greenfield vena caval filter was employed for treatment of a femoral thrombus or pulmonary embolism in postoperative hip patients who developed bleeding complications from heparin, had a recurrent embolism while on heparin, or who had had a contraindication to anticoagulation therapy.

    View details for Web of Science ID A1986A768700023

    View details for PubMedID 3956011

  • 3-DIMENSIONAL IMAGING OF BONE FROM COMPUTERIZED-TOMOGRAPHY CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Woolson, S. T., Dev, P., FELLINGHAM, L. L., Vassiliadis, A. 1986: 239-248

    Abstract

    An automatic computer technique was designed to produce three-dimensional (3D) images of bony anatomy on a cathode ray tube (CRT) from computerized tomography (CT) data. The authors transferred CT scan data of a cadaver and 11 patients to a computer system via magnetic tape. An automatic edge extraction algorithm generated an outline of bone specified by a range of CT numbers for each scan slice. These outlines were stacked in the computer and various graphics options used to represent the 3D anatomy of bone on a high-resolution CRT screen. The 3D image data were interfaced with a three-axis computer numerically controlled milling device to produce solid models of these bone images. Comparison of the dimensions of the solid models of the femur, hemipelvis, and femoral medullary canal to the actual cadaver specimen demonstrated that the models were accurate in size to within 1-3 mm. These 3D images and solid models will be helpful for preoperative diagnosis, surgical planning, and customized prosthesis manufacture in complex orthopaedic cases.

    View details for Web of Science ID A1986AYQ7700035

    View details for PubMedID 3955956

  • Time-related improvement in the range of motion of the hip after total replacement. journal of bone and joint surgery. American volume Woolson, S. T., Maloney, W. J., Schurman, D. J. 1985; 67 (8): 1251-1254

    Abstract

    We studied the progression of improvement in the range of motion of the hip after total hip replacement as it was related to time postoperatively. One hundred and eight hip replacements performed by members of the Stanford University Division of Orthopaedic Surgery in ninety-two patients were included in the analysis. The hips had no major postoperative complications, and the range of motion was examined preoperatively; at six months, one year, and two years, postoperatively; and at a last follow-up examination at a minimum of 4.5 years. There was no statistically significant improvement in the flexion and abduction of the hip after the one-year follow-up visit, but adduction and internal and external rotation were improved significantly at the last follow-up (average, 7.5 years). Of multiple variables that were studied, including those related to the patient, to the size and design of the prosthesis, and to the orientation of the total hip components, only the preoperative range of motion of the hip and a history of previous surgical treatment were major determining factors in the postoperative improvement of the range of motion.

    View details for PubMedID 4055850

  • A METHOD OF INTRAOPERATIVE LIMB LENGTH MEASUREMENT IN TOTAL HIP-ARTHROPLASTY CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Woolson, S. T., Harris, W. H. 1985: 207-210

    Abstract

    Equalization of leg-length discrepancy during total hip arthroplasty is a major concern to both the patient and surgeon. A stable pelvic reference point must be established during surgery to determine leg-length changes. An accurate method of intraoperative leg-length measurement is presented to improve the surgeon's ability to determine the exact amount of limb lengthening or shortening occurring during total hip arthroplasty.

    View details for Web of Science ID A1985AFD9200032

    View details for PubMedID 3978918

  • 3-DIMENSIONAL IMAGING OF THE ANKLE JOINT FROM COMPUTERIZED-TOMOGRAPHY FOOT & ANKLE Woolson, S. T., Dev, P., FELLINGHAM, L., Vassiliadis, A. 1985; 6 (1): 2-6

    Abstract

    A computer system was developed to rapidly reconstruct three-dimensional (3D) images of bone from computerized tomography scans of the ankle joint. Solid models of the bones were produced from the 3D image data through the use of a computer numerically controlled milling machine. A cadaver ankle joint was scanned, and models of the distal tibia and fibula and dome of the talus were made and compared to the actual bone specimens. The measurements of the models were within 3 mm or less of the bones in all three planes (average, 1.2 mm or 5.5%). These 3D images and models of bone should allow better visualization of joint pathology and a system for preoperative planning on exact bone models to optimize the results of surgery.

    View details for Web of Science ID A1985APL2400001

    View details for PubMedID 4043888

  • 3 DIMENSIONAL IMAGING OF BONE FROM ANALYSIS OF COMPUTED-TOMOGRAPHY DATA ORTHOPEDICS Woolson, S. T., FELLINGHAM, L. L., Dev, P., Vassiliadis, A. 1985; 8 (10): 1269-1273

    Abstract

    A computer system was developed to reconstruct three dimensional images of bone from analysis of computed tomography data. Images of bone can be made within minutes and rotated for viewing from any direction. An editing process allows visualization of the articular surfaces of any joint. Solid models of the bone images can be produced with an accuracy of 1 mm to 3 mm by interfacing the image data with a computer numerically controlled milling machine. This technology will provide better information to the surgeon for preoperative diagnosis and planning and for the design of customized implants.

    View details for Web of Science ID A1985ATH7600007

    View details for PubMedID 3841589

  • ACETABULAR COMPONENT MIGRATION FOLLOWING TRAUMATIC TOTAL HIP DISLOCATION - A CASE-REPORT CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Woolson, S. T. 1984: 42-44

    Abstract

    A 40-year-old man with a total hip arthroplasty was injured in an auto accident. The injury was a posterior fracture-dislocation of the total hip and produced migration of a dislocated acetabular prosthesis. A large hematoma extended from the hip to the medial aspect of the thigh. This unusual case illustrates the importance of obtaining serial roentgenograms for hip arthroplasties and for injuries of the hip joint.

    View details for Web of Science ID A1984SW27700007

    View details for PubMedID 6373090

  • COMPLEX TOTAL HIP-REPLACEMENT FOR DYSPLASTIC OR HYPOPLASTIC HIPS USING MINIATURE OR MICROMINIATURE COMPONENTS JOURNAL OF BONE AND JOINT SURGERY-AMERICAN VOLUME Woolson, S. T., Harris, W. H. 1983; 65 (8): 1099-1108

    Abstract

    We analyzed the preoperative and perioperative data on sixty-nine consecutive complex total hip replacements performed in fifty-seven patients using miniature or microminiature custom-made femoral components. The patients' average age was 45.7 years. The preoperative diagnosis was congenital dysplasia or dislocation of the hip in 72 per cent of the hips. Acetabular bone grafts were required in thirty-seven of the sixty-nine hips. Operative complications occurred in thirteen (19 per cent) and postoperative dislocation occurred in eleven (16 per cent) of the sixty-nine hips. Fifty-five hips in forty-seven patients were followed for a minimum of two years, the average follow-up being 4.8 years and the longest, 9.8 years. All acetabular grafts united. Loosening of one or both prosthetic components occurred in ten (18 per cent) of the fifty-five hips (twelve of the 110 components became loose). There were no instances of a stem bending or fracturing, despite the small size of the femoral components. Eight hips (14.5 per cent) had undergone revision, six for painful loose components and two for recurrent dislocation. For the forty-seven hips that were not revised, the average Harris hip score rose from 43 points preoperatively to 80 points postoperatively.

    View details for Web of Science ID A1983RM57700006

    View details for PubMedID 6355111

  • A method of balanced skeletal traction for femoral fractures. journal of bone and joint surgery. American volume Woolson, S. T., Meeks, L. W. 1974; 56 (6): 1288-1289

    View details for PubMedID 4436365

  • URINARY-TRACT COMPLICATIONS OF ANORECTAL SURGERY AMERICAN JOURNAL OF SURGERY TANK, E. S., Woolson, S. T., Lapides, J., Ernst, C. B. 1972; 123 (1): 118-?

    View details for Web of Science ID A1972L471100016

    View details for PubMedID 5062031

Conference Proceedings


  • Acetabular Component Positioning Using the Transverse Acetabular Ligament Can You Find It and Does It Help? Epstein, N. J., Woolson, S. T., Giori, N. J. SPRINGER. 2011: 412-416

    Abstract

    Several studies have reported that the transverse acetabular ligament (TAL) can be used to orient the acetabular component during total hip arthroplasty and that it can be identified in nearly all patients.We attempted to determine how often the TAL could be identified during primary THA and its accuracy as a guide for acetabular component positioning.In a prospective series of 63 patients (64 hips) undergoing primary THA, two surgeons attempted to identify the TAL and, if it was found, to use it for acetabular component orientation. Patients in whom the TAL was identified served as the study group and the ligament was used for cup orientation in those patients; the remaining patients in whom the ligament could not be identified served as a control group and had free-hand cup positioning. Anteversion was determined by radiographic measurement from true lateral views.The TAL was identified in only 30 hips (47%) and was more likely to be found in patients who did not have inferior acetabular osteophytes. Acetabular position was not improved using this ligament for reference.The TAL could not be routinely identified at surgery and when used for cup orientation it was no more accurate for cup positioning than free-hand technique.

    View details for DOI 10.1007/s11999-010-1523-1

    View details for Web of Science ID 000286939300013

    View details for PubMedID 20737303

  • Fixation, polyethylene wear, and pelvic osteolysis in primary total hip replacement Maloney, W. J., Galante, J. O., Anderson, M., Goldberg, V., Harris, W. H., Jacobs, J., Kraay, M., Lachiewicz, P., Rubash, H. E., Schutzer, S., Woolson, S. T. SPRINGER. 1999: 157-164

    Abstract

    A multicenter retrospective review was performed analyzing 1081 primary total hip replacements in 944 patients using the Harris Galante-I cementless acetabular component with screw fixation. All patients were followed up for a minimum of 5 years with a mean followup of 81 months. Linear polyethylene wear averaged 0.11 mm/year (range, 0-0.86 mm/year). Pelvic osteolysis was seen in 25 patients (2.3%). Migration of the acetabular component was seen in four hips. A subgroup of patients was reanalyzed at a minimum followup of 10 years. The mean linear polyethylene wear rate remained 0.11 mm/year. In this group, only one socket had migrated. There was an association between wear rate and age. On average, younger patients had higher wear rates. The risk for having pelvic osteolysis develop and the need for revision surgery also was age-related. Twenty-two percent of hip replacements (15 hips) in patients younger than 50 years of age at the time of their index operation had pelvic osteolysis develop. In contrast, for patients older than 50 years of age at the time of surgery only 7.8% (eight hips) had osteolysis of the pelvis develop. For patients older than 70 years of age at the time of primary total hip replacement, none had pelvic osteolysis develop.

    View details for Web of Science ID 000084102600017

    View details for PubMedID 10611870

  • VENOUS ULTRASONOGRAPHY IN THE DETECTION OF PROXIMAL VEIN-THROMBOSIS AFTER TOTAL KNEE ARTHROPLASTY Woolson, S. T., Pottorff, G. SPRINGER. 1991: 131-135

    Abstract

    A prospective study of the accuracy of real-time B-mode ultrasonography in detecting deep venous thrombosis in the proximal veins of the lower extremity was conducted in a consecutive series of total knee arthroplasty (TKA) patients. Ascending venography was used as the diagnostic standard. Ninety-six consecutive TKA procedures performed in 68 patients were considered. Eight extremities were excluded because paired ultrasonic and venographic studies were not performed. Eighty-eight extremities in 61 patients had paired studies (bilateral venous ultrasonography of the proximal veins and venography of the operated extremity), and were done at an average of eight days postoperatively. Both tests were done within 24 hours of each other (98% on the same day) and the radiologist and ultrasound technologist were blinded to the results of the others' study. Both tests were negative for proximal (common femoral through the popliteal vein) thrombosis in 72 extremities. Ten extremities had positive-paired tests for proximal thrombosis that correlated for thrombus size and location. There were five false-negative and one false-positive ultrasound studies for a sensitivity of 67%, a specificity of 99%, and an overall accuracy of 93%. Considering the 54 extremities that were examined after the vascular laboratory had gained considerable experience in venous imaging, the ultrasonic sensitivity, specificity, and overall accuracy rose to 83%, 100%, and 96% respectively. The authors believe that venous ultrasonography is accurate in the diagnosis of proximal vein thrombosis after TKA when the noninvasive vascular laboratory has experience with such studies.

    View details for Web of Science ID A1991GT89200019

    View details for PubMedID 1959260

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