Bio

Clinical Focus


  • Orthopaedic Surgery
  • foot and ankle sports injuries
  • foot and ankle reconstruction

Academic Appointments


Administrative Appointments


  • Team Physician, Stanford Football Program (2009 - Present)
  • Team Physician, Stanford Athletic Department (2009 - Present)
  • Orthopaedic Foot and Ankle Consultant, San Francisco 49ers (2009 - Present)
  • Orthopaedic Foot and Ankle Consultant, Golden Stat Warriors (2011 - Present)

Honors & Awards


  • Young Investigator Award, Western Orthopaedic Association (June 2012)
  • Russell Hibbs Award - Best Basic Science Presentation, 42nd Annual Meeting of the Scoliosis Research Society (September 2007)

Professional Education


  • Residency:University of Utah - Dept of Orthopaedics (2008) UT
  • Internship:University of Utah School of Medicine (2004) UT
  • Board Certification, American Board of Orthopaedic Surgeons, Orthopaedic Surgery
  • Fellowship:Orthocarolina and Carolinas Medical Center (2009) NC
  • Medical Education:University of Utah School of Medicine (2003) UT
  • Fellowship, Carolinas Medical Center, OrthoCarolina, Foot and Ankle Surgery
  • Residency, University of Utah Hospital, Orthopaedic Surgery
  • M.D., University of Utah, School of Medicine
  • B.S., Brigham Young University, Nutritional Science

Research & Scholarship

Current Research and Scholarly Interests


Research Focus:
-Evaluation and treatment of foot and ankle injuries in athletes
-Surgical treatment of Achilles tendon disorders
-Locked and non-locked plate fixation techniques for foot and ankle trauma and arthrodesis
-Post-operative pain control following surgical procedures in the foot and ankle

Teaching

2013-14 Courses


Publications

Journal Articles


  • Use of patient-reported outcome measures in foot and ankle research. journal of bone and joint surgery. American volume Hunt, K. J., Hurwit, D. 2013; 95 (16): e1181-9

    Abstract

    In the orthopaedic literature, there is a wide range of clinical outcome measurement tools that have been used in evaluating foot and ankle procedures, disorders, and outcomes, with no broadly accepted consensus as to which tools are preferred. The purpose of this study was to determine the frequency and distribution of the various outcome instruments used in the foot and ankle literature, and to identify trends for use of these instruments over time.We conducted a systematic review of all original clinical articles reporting on foot and/or ankle topics in six orthopaedic journals over a ten-year period (2002 to 2011). All clinical patient-reported outcome rating instruments used in these articles were recorded, as were study date, study design, clinical topic, and level of evidence.A total of 878 clinical foot and ankle articles that used at least one patient-reported outcome measure were identified among 16,513 total articles published during the ten-year period. There were 139 unique clinical outcome scales used, and the five most popular scales (as a percentage of foot/ankle outcome articles) were the American Orthopaedic Foot & Ankle Society (AOFAS) scales (55.9%), visual analog scale (VAS) for pain (22.9%), Short Form-36 (SF-36) Health Survey (13.7%), Foot Function Index (FFI) (5.5%), and American Academy of Orthopaedic Surgeons (AAOS) outcomes instruments (3.3%). The majority of articles described Level-IV studies (70.1%); only 9.4% reported Level-I studies.A considerable variety of outcome measurement tools are used in the foot and ankle clinical literature, with a small proportion used consistently. The AOFAS scales continue to be used at a high rate relative to other scales that have been validated. Data from the present study underscore the need for a paradigm shift toward the use of consistent, valid, and reliable outcome measures for studies of foot and ankle procedures and disorders. It is not clear which existing validated outcome instruments will emerge as widely used and clinically meaningful.These data support the need for a paradigm shift toward the consistent use of valid and reliable outcome measures for foot and ankle clinical research.

    View details for DOI 10.2106/JBJS.L.01476

    View details for PubMedID 23965711

  • Foot and ankle injuries in sport: imaging correlation with arthroscopic and surgical findings. Clinics in sports medicine Hunt, K. J., Githens, M., Riley, G. M., Kim, M., Gold, G. E. 2013; 32 (3): 525-557

    Abstract

    Foot and ankle injuries are common in sport. Although many available imaging techniques can be useful in identifying and classifying injuries, magnetic resonance imaging (MRI) provides high levels of sensitivity and specificity for articular and soft-tissue injuries. Arthroscopic and minimally invasive treatment techniques for foot and ankle injuries are rapidly evolving, minimizing morbidity and improving postoperative rehabilitation and return to play. Correlation between MRI and surgical findings can aid in both accessing and treating pathologic processes and structures.

    View details for DOI 10.1016/j.csm.2013.03.007

    View details for PubMedID 23773880

  • Treatment of Jones Fracture Nonunions and Refractures in the Elite Athlete Outcomes of Intramedullary Screw Fixation With Bone Grafting AMERICAN JOURNAL OF SPORTS MEDICINE Hunt, K. J., Anderson, R. B. 2011; 39 (9): 1948-1954

    Abstract

    Fractures of the proximal fifth metatarsal metaphysis (ie, the Jones fracture) can be problematic in the elite athlete because of a high incidence of nonunion and refracture with nonoperative treatment. Although these fractures are not common, athletes can suffer refracture or nonunion of a Jones fracture despite operative stabilization. This is often attributable to hardware of insufficient strength, aggressive postoperative rehabilitation, or biologic insufficiency at the fracture site.The authors review the results of revision intramedullary screw fixation with cancellous autologous bone grafting or bone-marrow aspirate combined with demineralized bone matrix after refracture or nonunion of Jones fractures in elite athletes. StudyCase series; Level of evidence, 4.The authors retrospectively reviewed the clinical and radiographic outcomes and return to sport in 21 elite athletes undergoing treatment of Jones fracture refractures or nonunions. All patients underwent intramedullary screw fixation with autologous bone graft (12 patients), bone-marrow aspirate (BMA) + demineralized bone matrix (DBM) (8 patients), or no bone graft (1 patient).All athletes were able to return to their previous level of athletic competition at an average of 12.3 weeks. All fractures showed clinical and radiographic evidence of compete cortical healing. Only 1 patient subsequently suffered a refracture.The authors recommend revision fixation with a large, solid screw (5.5 mm or larger) and autologous bone grafting for symptomatic refractures and nonunions of the proximal fifth metatarsal in elite athletes. Additional investigation is needed to determine whether BMA combined with DBM is an effective substitute for cancellous autograft.

    View details for DOI 10.1177/0363546511408868

    View details for Web of Science ID 000294486000018

    View details for PubMedID 21632977

  • Continuous peripheral nerve blockade as post-operative analgesia for open treatment of calcaneal fractures. J Orthop Trauma Hunt KJ, Higgins TF, Carlston CV, Swenson, JR, McEachern JE, Beals TC. 2010; 24 (3): 148-55
  • Foot and Ankle Problems Related to Sports: Introduction and Approach to Management. J Amer Acad Orthop Surg Anderson RB, Hunt KJ, McCormick JJ 2010; in press
  • Management of Forefoot Injuries in the Athlete Operative Techniques in Sports Medicine. Hunt KJ, McCormick JJ, Anderson RB 2009; in press
  • Heel pain in the athlete. Sports Health: A Multi-Disciplinary Approach. Hunt KJ, Anderson RB 2009; 1: 427-434
  • Epidemiology of syndesmosis injuries in intercollegiate football: incidence and risk factors from National Collegiate Athletic Association injury surveillance system data from 2004-2005 to 2008-2009. Clinical journal of sport medicine Hunt, K. J., George, E., Harris, A. H., Dragoo, J. L. 2013; 23 (4): 278-282

    Abstract

    OBJECTIVE:: To describe the incidence and risk factors for high ankle sprains (ie, syndesmosis injuries) among National Collegiate Athletic Association (NCAA) football players. DESIGN:: Descriptive epidemiologic study. SETTING:: Data were examined from the NCAA's Injury Surveillance System (ISS) for 5 football seasons (from 2004-2005 to 2008-2009). PARTICIPANTS:: All NCAA men's football programs participating in the ISS. ASSESSMENT OF RISK FACTORS:: No additional risk factors were introduced as a result of this analysis. MAIN OUTCOME MEASURES:: For partial and complete syndesmosis injuries, outcome measures included incidence, time lost from participation, and requirement for surgical repair. RESULTS:: The overall incidence of high ankle sprains in NCAA football players was 0.24 per 1000 athlete exposures, accounting for 24.6% of all ankle sprains. Athletes were nearly 14 times more likely to sustain the injury during games compared with practice; complete syndesmosis injuries resulted in significantly greater time lost compared with partial injuries (31.3 vs 15.8 days). Less than 3% of syndesmosis injuries required surgical intervention. There was a significantly higher injury incidence on artificial surfaces compared with natural grass. The majority of injuries (75.2%) occurred during contact with another player. CONCLUSIONS:: Our data suggest a significantly higher incidence of syndesmosis injuries during games, during running plays, and to running backs and interior defensive linemen. The wide range in time lost from participation for complete syndesmosis injuries underscores the need for improved understanding of injury mechanism and classification of injury severity such that prevention, safe return to play protocols, and outcomes can be further improved.

    View details for DOI 10.1097/JSM.0b013e31827ee829

    View details for PubMedID 23339895

  • Biplanar Proximal Phalanx Closing Wedge Osteotomy for Hallux Rigidus FOOT & ANKLE INTERNATIONAL Hunt, K. J., Anderson, R. B. 2012; 33 (12): 1043-1050

    Abstract

    Many procedures have been described for surgical treatment of symptomatic hallux rigidus. Dorsal cheilectomy of the metatarsophalangeal joint combined with a dorsal-based closing wedge osteotomy of the proximal phalanx (i.e., Moberg procedure) has been described as an effective procedure. For patients with hallux rigidus and clinically significant hallux valgus interphalangeus, the authors previously described a dorsal cheilectomy combined with a biplanar closing wedge osteotomy of the proximal phalanx, combining a Moberg osteotomy with an Akin osteotomy. The purpose of this study was to describe the clinical results of this procedure.This article is a retrospective review of prospectively gathered data that reports the clinical and radiographic results of dorsal cheilectomy combined with a biplanar oblique closing wedge proximal phalanx osteotomy (i.e., Moberg-Akin procedure) for patients with symptomatic hallux rigidus and hallux valgus interphalangeus. Consecutive patients were followed and evaluated for clinical and radiographic healing, satisfaction, and ultimate need for additional procedure(s). Thirty-five feet in 34 patients underwent the procedure.All osteotomies healed. At an average of 22.5 months of follow-up, 90% of patients reported good or excellent results, with pain relief, improved function, and fewer shoe wear limitations following this procedure. Hallux valgus and hallux interphalangeal angles were radiographically improved. Other than one patient who requested hardware removal, no patients required additional surgical procedures.Dorsal cheilectomy combined with a Moberg-Akin procedure was an effective and durable procedure with minimal morbidity in patients with hallux rigidus combined with hallux valgus interphalangeus.

    View details for DOI 10.3113/FAI.2012.1043

    View details for Web of Science ID 000311528300001

    View details for PubMedID 23199851

  • Locked Versus Nonlocked Plate Fixation for First Metatarsophalangeal Arthrodesis: A Biomechanical Investigation FOOT & ANKLE INTERNATIONAL Hunt, K. J., Barr, C. R., Lindsey, D. P., Chou, L. B. 2012; 33 (11): 984-990

    Abstract

    First metatarsophalangeal (MTP) arthrodesis using dorsal plate fixation is a common procedure for painful conditions of the great toe. Locked plates have become increasingly common for arthrodesis procedures in the foot, including the hallux MTP joint. The biomechanical advantages and disadvantages of these plates are currently unknown. The purpose of this study was to compare locked and nonlocked plates used for first MTP fusion for strength and stiffness.The first ray of nine matched pairs of fresh-frozen cadaveric feet underwent dissection, preparation with cup-and-cone reamers, and fixation of the MTP joint with a compression screw and either a nonlocked or locked stainless steel dorsal plate. Each specimen was loaded in a cantilever fashion to 90 N at a rate of 3 Hz for a total of 250,000 cycles. The amount of plantar MTP gap was recorded using a calibrated extensometer. Load-to-failure testing was performed for all specimens that endured the entire cyclical loading. Stiffness was calculated from the final load-to-failure test.The locked plate group demonstrated significantly less plantar gapping during fatigue endurance testing from cycle 10,000 through 250,000 (p < .05). Mean stiffness was significantly greater in the locked plate group compared with the nonlocked plate group (p = .02). There was no significant difference in load to failure between the two groups (p = .27).Compared with nonlocked plates, locked hallux MTP arthrodesis plates exhibited significantly less plantar gapping after 10,000 cycles of fatigue endurance testing and significantly greater stiffness in load-to-failure testing.As the use of locked plate technology is becoming increasingly common for applications in the foot, a thorough understanding of the biomechanical characteristics of these implants may help optimize their indications and clinical use.

    View details for DOI 10.3113/FAI.2012.0984

    View details for Web of Science ID 000310865100009

    View details for PubMedID 23131445

  • Foot and Ankle Questions on the Orthopaedic In-Training Examination: Analysis of Content, Reference, and Performance ORTHOPEDICS Barr, C. R., Cheng, I., Chou, L. B., Hunt, K. J. 2012; 35 (6): E880-E888

    Abstract

    The purpose of this study was to provide a comprehensive analysis of the Orthopaedic In-Training Examination's (OITE's) questions, question sources, and resident performance over the course of residency training.The authors analyzed all OITE questions pertaining to foot and ankle surgery between 2006 and 2010. Recorded data included the topic and area tested, imaging modality used, tested treatment method, taxonomic classification, cited references, and resident performance scores. Foot- and ankle-related questions made up 13.9% (186/1341) of the OITE questions. Thirteen general topic areas were identified, with the most common being foot and ankle trauma, the pediatric foot, and foot and ankle deformity. Imaging modalities were tested in approximately half of the questions. Knowledge of treatment modalities was required in 58.1% (108/186) of the questions. Recall-type questions were the most common. Trends existed in the recommended references, with 2 journals and 1 textbook being commonly and consistently cited: Foot and Ankle International, The Journal of Bone and Joint Surgery American Volume, and Surgery of the Foot and Ankle, respectively. Resident performance scores increased with each successive level of training.An understanding of the topics and resources used for OITE foot and ankle questions is an important aid in creating or improving residency programs' foot and ankle education curricula. With knowledge of question content, source, and resident performance, education can be optimized toward efficient learning and improved scores on this section of the examination.

    View details for DOI 10.3928/01477447-20120525-28

    View details for Web of Science ID 000305430300016

    View details for PubMedID 22691661

  • Osteochondral Lesions of the Talus Effect of Defect Size and Plantarflexion Angle on Ankle Joint Stresses AMERICAN JOURNAL OF SPORTS MEDICINE Hunt, K. J., Lee, A. T., Lindsey, D. P., Slikker, W., Chou, L. B. 2012; 40 (4): 895-901

    Abstract

    Osteochondral lesions of the talus (OLTs) are a common cause of ankle pain and disability. Current clinical guidelines favor autogenous or allogenic osteochondral grafting procedures for lesions larger than 10 mm in diameter because of increased failure rates in these larger lesions with arthroscopic debridement, curettage, and microfracture. There are currently no biomechanical data nor level I clinical data supporting this size threshold.The purpose of this study was to determine the effect of OLT defect size on stress concentration, rim stress, and location of peak stress and whether a threshold defect size exists.Descriptive laboratory study.Progressively larger medial OLTs were created (6, 8, 10, and 12 mm) in 8 fresh-frozen cadaveric ankle joints. With a calibrated Tekscan pressure sensor in the tibiotalar joint, an axial load of 686 N was applied, and pressure was recorded in neutral and 15° of plantar flexion with each defect size. Peak stress, contact area, peak and average rim stresses, and location of peak stress were determined.The distance between peak stress and defect rim was significantly decreased with increasing defect size for lesions of 10 mm and larger. Total tibiotalar contact area was significantly decreased with increasing defect size and with ankle plantar flexion. While peak joint stress and peak rim stress were not affected by defect size or plantar flexion, average rim stress was significantly increased by plantar flexion.Reduction in contact area and shift in the location of peak stress with increasing defect size may contribute to articular cartilage degeneration, pain, and defect enlargement in patients with OLTs. There appears to be a threshold of 10 mm after which the distance between the rim of the defect and the peak stress decreases; however, there is no change in peak stress magnitude with increasing defect size.The location of peak stress in the ankle joint becomes closer to the rim of the defect in OLTs at a threshold of 10 mm and greater in diameter. These data may have implications toward OLT size thresholds for surgical decision making in symptomatic lesions (ie, primary osteochondral transplantation procedure vs curettage and debridement). The ultimate goal is to determine whether there is a threshold defect size for primary osteoarticular graft techniques.

    View details for DOI 10.1177/0363546511434404

    View details for Web of Science ID 000302285100022

    View details for PubMedID 22366518

  • Locked Versus Nonlocked Plate Fixation For Hallux MTP Arthrodesis FOOT & ANKLE INTERNATIONAL Hunt, K. J., Ellington, J. K., Anderson, R. B., Cohen, B. E., Davis, W. H., Jones, C. P. 2011; 32 (7): 704-709

    Abstract

    Dorsal plate fixation is used commonly for arthrodesis of the hallux first metatarsophalangeal (MTP) joint. Custom dorsal plates incorporating locking technology have been developed recently for applications in the foot to provide relative ease of application and theoretically superior mechanical properties. The purpose of this study is to compare the radiographic and clinical outcomes of patients undergoing hallux MTP joint arthrodesis using a locked plate, or a nonlocked plate.We compared consecutive patients who underwent hallux MTP arthrodesis for a variety of diagnoses with either a precontoured locked titanium dorsal plate (Group 1) or a precontoured, nonlocked stainless steel plate (Group 2). All patients were evaluated with radiographs, visual analog pain scale, American Orthopaedic Foot and Ankle Society (AOFAS) hallux score, and a detailed patient satisfaction survey.There were 73 feet in Group 1 and 107 feet in Group 2. There was a trend toward a higher nonunion rate in Group 1 compared to Group 2. When considering only patients without rheumatoid arthritis (RA), the union rate was significantly higher in Group 2 compared to Group 1. Hardware failure and the overall complication rate was equivalent between the two Groups.As locked plate technology continues to gain popularity for procedures in the foot, it is important that clinical outcomes are reported. Locked titanium plates were associated with higher nonunion rates. Improved plate design, patient selection, and an understanding of plate biomechanics in this unique loading environment may optimize future outcomes for hallux MTP arthrodesis.

    View details for DOI 10.3113/FAI.2011.0704

    View details for Web of Science ID 000292359700009

    View details for PubMedID 21972766

  • Management of Common Sports-related Injuries About the Foot and Ankle JOURNAL OF THE AMERICAN ACADEMY OF ORTHOPAEDIC SURGEONS Anderson, R. B., Hunt, K. J., McCormick, J. J. 2010; 18 (9): 546-556

    Abstract

    Foot and ankle injuries are commonplace in competitive sports. Improvements in injury surveillance programs and injury reporting have enabled physicians to better recognize and manage specific foot and ankle injuries, with a primary goal of efficient and safe return to play. Athletes are becoming stronger, faster, and better conditioned, and higher-energy injuries are becoming increasingly common. Close attention is required during examination to accurately identify such injuries as turf toe, ankle injuries, tarsometatarsal (ie, Lisfranc) injuries, and stress fractures. Early diagnosis and management of these injuries are critical. Ultimately, however, pressure to return to play must not compromise appropriate care and long-term outcomes.

    View details for Web of Science ID 000281454900006

    View details for PubMedID 20810936

  • Ultrasound guided sciatic nerve block for foot and ankle surgery: a prospective study Clin Orthop and Rel Res Beals TC, Hunt KJ, Saltzman CL 2010; in press
  • The Effect of Two Clinically Relevant Fusionless Scoliosis Implant Strategies on the Health of the Intervertebral Disc Spine Hunt KJ, Braun JT, Christensen BA 2010; 35 (4): 371-7
  • Treatment of Jones fracture non-unions and refractures in the elite athlete Am J Sports Med Hunt KJ, Anderson RB 2010; in review
  • Cementation of a Polyethylene Liner Into a Metal Acetabular Shell A Biomechanical Study JOURNAL OF ARTHROPLASTY Hofmann, A. A., Prince, E. J., Drake, F. T., Hunt, K. J. 2009; 24 (5): 775-782

    Abstract

    Cementation of a liner into a well-fixed acetabular shell is common in revision hip arthroplasty. We compare the biomechanical strengths of cemented liners with standard locked liners. Fifty polyethylene liners were inserted into acetabular shells using the standard locking mechanism or 1 of 2 cement types then loaded to failure by torsion or lever-out testing. Lever-out testing showed that all cemented liners failed at similar loads to standard locked liners. With torsion testing, cemented liners failed at significantly higher loads than standard locked liners; roughening the liner increased load to failure. Cementation of an acetabular liner into a metal shell is safe and strong and a good alternative to metal shell replacement. Saw roughening of the polyethylene liner strengthens the poly-cement interface.

    View details for DOI 10.1016/j.arth.2008.05.027

    View details for Web of Science ID 000269404200018

    View details for PubMedID 18701253

  • Single-Injection Femoral and Sciatic Nerve Blocks for Pain Control After Total Knee Arthroplasty JOURNAL OF ARTHROPLASTY Hunt, K. J., Bourne, M. H., Mariani, E. M. 2009; 24 (4): 533-538

    Abstract

    This study was designed to evaluate the addition of a single-injection sciatic nerve block to a femoral nerve block for analgesia after total knee arthroplasty. Fifty-seven patients undergoing primary total knee arthroplasty were randomized to receive femoral nerve blockade or a sham block. A subsequent 31 patients received both femoral and sciatic nerve blocks (FSNBs) before general anesthesia. Intravenous morphine use and visual analog pain scale scores were recorded at regular intervals. Femoral and sciatic nerve blocks were placed in less than five minutes, on average. Lower visual analog pain scale scores were noted in both femoral nerve blockade and FSNB groups compared to shams through 48 hours. Morphine use was significantly lower in the FSNB group. Femoral and sciatic nerve block can be placed quickly and consistently in the operating room with improved postoperative pain relief and reduced narcotic consumption.

    View details for DOI 10.1016/j.arth.2008.04.005

    View details for Web of Science ID 000266846500007

    View details for PubMedID 19026519

  • Percutaneous curettage and bone grafting for humeral simple bone cysts. Orthopedics Hunt, K. J., Bergeson, A., Coffin, C. M., Randall, R. L. 2009; 32 (2): 89-?

    Abstract

    Traditional treatments for simple bone cysts are associated with significant surgical morbidity and high recurrence rates. The purpose of this study was to evaluate the effectiveness of a percutaneous approach to the treatment of proximal humeral simple bone cysts that includes percutaneous decompression, curettage, and injection of allogeneic cancellous bone combined with autologous bone marrow. Twenty-one children (average age, 10.1+/-4.6 years) with symptomatic simple bone cysts of the proximal humerus were surgically treated with percutaneous cyst decompression, curettage, and cancellous allograft combined with autologous bone marrow. Patients were observed in-clinic with serial examinations and radiographs. Fracture healing and cyst recurrence were determined at follow-up. All patients returned to activities of daily living with full range of motion and were completely asymptomatic. All fractures healed. There were no surgical complications or refractures. Five patients demonstrated radiographic evidence of partial cyst recurrence and required additional surgical treatment. One patient required a third operative procedure for a second recurrence. Three of 8 active cysts demonstrated partial recurrence. Recurrence was associated with younger age. Our goal in the treatment of proximal humeral simple bone cysts is to prevent cyst recurrence and pathologic refracture. Radiographic evidence of cyst resolution occurred in 75% of our patients using percutaneous curettage and bone grafting, and in 95% of patients with a second procedure. As expected, partial recurrence of active cysts after treatment with this method is high. This percutaneous technique is a safe and effective treatment for humeral simple bone cysts.

    View details for PubMedID 19301802

  • Variations in corticosteroid/anesthetic injections for painful shoulder conditions: comparisons among orthopaedic surgeons, rheumatologists, and physical medicine and primary-care physicians BMC MUSCULOSKELETAL DISORDERS Skedros, J. G., Hunt, K. J., Pitts, T. C. 2007; 8

    Abstract

    Variations in corticosteroid/anesthetic doses for injecting shoulder conditions were examined among orthopaedic surgeons, rheumatologists, and primary-care sports medicine (PCSMs) and physical medicine and rehabilitation (PMRs) physicians to provide data needed for documenting inter-group differences for establishing uniform injection guidelines.264 surveys, sent to these physicians in our tri-state area of the western United States, addressed corticosteroid/anesthetic doses and types used for subacromial impingement, degenerative glenohumeral and acromioclavicular arthritis, biceps tendinitis, and peri-scapular trigger points. They were asked about preferences regarding: 1) fluorinated vs. non-fluorinated corticosteroids, 2) acetate vs. phosphate types, 3) patient age, and 4) adjustments for special considerations including young athletes and diabetics.169 (64% response rate, RR) surveys were returned: 105/163 orthopaedic surgeons (64%RR), 44/77 PCSMs/PMRs (57%RR), 20/24 rheumatologists (83%RR). Although corticosteroid doses do not differ significantly between specialties (p > 0.3), anesthetic volumes show broad variations, with surgeons using larger volumes. Although 29% of PCSMs/PMRs, 44% rheumatologists, and 41% surgeons exceed "recommended" doses for the acromioclavicular joint, >98% were within recommendations for the subacromial bursa and glenohumeral joint. Depo-Medrol(R) (methylprednisolone acetate) and Kenalog(R) (triamcinolone acetonide) are most commonly used. More rheumatologists (80%) were aware that there are acetate and phosphate types of corticosteroids as compared to PCSMs/PMRs (76%) and orthopaedists (60%). However, relatively fewer rheumatologists (25%) than PCSMs/PMRs (32%) or orthopaedists (32%) knew that phosphate types are more soluble. Fluorinated corticosteroids, which can be deleterious to soft tissues, were used with these frequencies for the biceps sheath: 17% rheumatologists, 8% PCSMs/PMRs, 37% orthopaedists. Nearly 85% use the same non-fluorinated corticosteroid for all injections; <10% make adjustments for diabetic patients.Variations between specialists in anesthetic doses suggest that surgeons (who use significantly larger volumes) emphasize determining the percentage of pain attributable to the injected region. Alternatively, this might reflect a more profound knowledge that non-surgeons specialists have of the potentially adverse cardiovascular effects of these agents. Variations between these specialists in corticosteroid/anesthetic doses and/or types, and their use in some special situations (e.g., diabetics), bespeak the need for additional investigations aimed at establishing uniform injection guidelines, and for identifying knowledge deficiencies that warrant advanced education.

    View details for DOI 10.1186/1471-2474-8-63

    View details for Web of Science ID 000249079400001

    View details for PubMedID 17617900

  • Ontogenetic structural and material variations in ovine calcanei: A model for interpreting bone adaptation ANATOMICAL RECORD-ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY Skedros, J. G., Sorenson, S. M., Hunt, K. J., Holyoak, J. D. 2007; 290 (3): 284-300

    Abstract

    Experimental models are needed for resolving relative influences of genetic, epigenetic, and nonheritable functionally induced (extragenetic) factors in the emergence of developmental adaptations in limb bones of larger mammals. We examined regional/ontogenetic morphologic variations in sheep calcanei, which exhibit marked heterogeneity in structural and material organization by skeletal maturity. Cross-sections and lateral radiographs of an ontogenetic series of domesticated sheep calcanei (fetal to adult) were examined for variations in biomechanically important structural (cortical thickness and trabecular architecture) and material (percent ash and predominant collagen fiber orientation) characteristics. Results showed delayed development of variations in cortical thickness and collagen fiber orientation, which correlate with extragenetic factors, including compression/tension strains of habitual bending in respective dorsal/plantar cortices and load-related thresholds for modeling/remodeling activities. In contrast, the appearance of trabecular arches in utero suggests strong genetic/epigenetic influences. These stark spatial/temporal variations in sheep calcanei provide a compelling model for investigating causal mechanisms that mediate this construction. In view of these findings, it is also suggested that the conventional distinction between genetic and epigenetic factors in limb bone development be expanded into three categories: genetic, epigenetic, and extragenetic factors.

    View details for DOI 10.1002/ar.20423

    View details for Web of Science ID 000245233100008

    View details for PubMedID 17525944

  • Surgical fixation of pathologic fractures: an evaluation of evolving treatment methods. Bulletin (Hospital for Joint Diseases (New York, N.Y.)) Hunt, K. J., Gollogly, S., Randall, R. L. 2006; 63 (3-4): 77-82

    Abstract

    The surgical techniques for the fixation of pathologic fractures continue to evolve. The present study examines clinical outcomes and complications associated with the use of newer generation interlocked intramedullary nails compared with open reduction and internal fixation with plates and screws for pathologic fractures in long bones. Fifty operative procedures performed on 37 patients by five community orthopaedic surgeons were retrospectively reviewed. The operative procedures were separated into two groups based upon the method of fracture fixation; the groups were compared for differences in hardware or fixation failure. The use of intramedullary devices was associated with a significantly lower number of hardware or fixation failures (p < 0.02). This data, in addition to several additional advantages of indirect reduction and intramedullary fixation of pathologic fractures, supports this method of fracture care over open reduction and internal fixation in appropriate cases.

    View details for PubMedID 16878822

  • Does the degree of laminarity correlate with site-specific differences in collagen fibre orientation in primary bone? An evaluation in the turkey ulna diaphysis JOURNAL OF ANATOMY Skedros, J. G., Hunt, K. J. 2004; 205 (2): 121-134

    Abstract

    de Margerie hypothesized that preferred orientations of primary vascular canals in avian primary cortical bone mediate important mechanical adaptations. Specifically, bones that receive habitual compression, tension or bending stresses typically have cortices with a low laminarity index (LI) (i.e. relatively lower cross-sectional areas of circularly (C) orientated primary vascular canals, and relatively higher areas of canals with radial (R), oblique (O) or longitudinal (L) orientations. By contrast, bones subject to habitual torsion have a high LI (i.e. relatively higher C-orientated canal area) [LI, based on percentage vascular canal area, = C/(C + R + O + L)]. Regional variations in predominant collagen fibre orientation (CFO) may be the adaptive characteristic mediated by LI. Using turkey ulnae, we tested the hypothesis that site-specific variations in predominant CFO and LI are strongly correlated. Mid-diaphyseal cross-sections (100 +/- 5 micro m) from subadult and adult bones were evaluated for CFO and LI using circularly polarized light images of cortical octants. Results showing significant differences between mean LI of subadult (40.0% +/- 10.7%) and adult (50.9% +/- 10.4%) (P < 0.01) bones suggest that adult bones experience more prevalent/predominant torsion. Alternatively, this relationship may reflect differences in growth rates. High positive correlations between LI and predominant CFO (subadults: r = 0.735; adults: r = 0.866; P < 0.001) suggest that primary bone can exhibit potentially adaptive material variations that are independent of secondary osteon formation.

    View details for Web of Science ID 000223101500004

    View details for PubMedID 15291795

  • Relationships of loading history and structural and material characteristics of bone: Development of the mule deer calcaneus JOURNAL OF MORPHOLOGY Skedros, J. G., Hunt, K. J., Bloebaum, R. D. 2004; 259 (3): 281-307

    Abstract

    If a bone's morphologic organization exhibits the accumulated effects of its strain history, then the relative contributions of a given strain stimulus to a bone's development may be inferred from a bone's hierarchical organization. The artiodactyl calcaneus is a short cantilever, loaded habitually in bending, with prevalent compression in the cranial (Cr) cortex, tension in the caudal (Cd) cortex, and shear in the medial and lateral cortices (i.e., neutral axis). Artiodactyl calcanei demonstrate unusually heterogeneous structural and material organization between these cortices. This study examines potential relationships between developmental morphologic variations and the functional strain distribution of the deer calcaneus. One calcaneus was obtained from each of 36 (fetus to adult) wild deer. Predominant collagen fiber orientation (CFO), microstructural characteristics, mineral content (% ash), and geometric parameters were determined from transversely cut segments. Radiographs were examined for arched trabeculae, which may reflect tension/compression stress trajectories. Results showed that cross-sectional shape changes with age from quasi-circular to quasi-elliptical, with the long axis in the cranial-caudal direction of habitual bending. Cranial ("compression") cortical thickness increased at a greater rate than the Cd ("tension") cortex. Fetal bones exhibited arched trabeculae. Percent ash was not uniform (Cr > Cd), and this disparity increased with age (absolute differences: 2.5% fetuses, 4.3% adults). Subadult bones showed progressively more secondary osteons and osteocyte lacunae in the Cr cortex, but the Cd cortex tended to have more active remodeling in the subadult and adult bones. Nonuniform Cr:Cd CFO patterns first consistently appear in the subadults, and are correlated with secondary bone formation and habitual strain mode. Medial and lateral cortices in these groups exhibited elongated secondary osteons. These variations may represent "strain-mode-specific" (i.e., tension, compression, shear) adaptations. The heterogeneous organization may also be influenced by variations in longitudinal strain magnitude (highest in the Cr cortex) and principal strain direction-oblique in medial-lateral cortices (where shear strains also predominate). Other factors such as local reductions in longitudinal strain may influence the increased remodeling activity of the Cd cortex. Some structural variations, such as arched trabeculae, that are established early in ontogeny may be strongly influenced by genetic- or epigenetic-derived processes. Material variations, such as secondary osteon population densities and CFO, which appear later, may be products of extragenetic factors, including microdamage.

    View details for DOI 10.1002/jmor.10167

    View details for Web of Science ID 000189353100003

    View details for PubMedID 14994328

  • Ontogenetic and regional morphologic variations in the turkey ulna diaphysis: implications for functional adaptation of cortical bone. The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology Skedros, J. G., Hunt, K. J., Hughes, P. E., Winet, H. 2003; 273 (1): 609-629

    Abstract

    This study examines relationships between bone morphology and mechanically mediated strain/fluid-flow patterns in an avian species. Using mid-diaphyseal transverse sections of domestic turkey ulnae (from 11 subadults and 11 adults), we quantified developmental changes in predominant collagen fiber orientation (CFO), mineral content (%ash), and microstructure in cortical octants or quadrants (i.e., %ash). Geometric parameters were examined using whole mid-diaphyseal cross-sections. The ulna undergoes habitual bending and torsion, and demonstrates nonuniform matrix fluid-flow patterns, and high circumferential strain gradients along the neutral axis (cranial-caudal) region at mid-diaphysis. The current results showed significant porosity differences: 1) greater osteocyte lacuna densities (N.Lac/Ar) (i.e., "non-vascular porosity") in the caudal and cranial cortices in both groups, 2) greater N.Lac/Ar in the pericortex vs. endocortex in mature bones, and 3) greater nonlacunar porosity (i.e., "vascular porosity") in the endocortex vs. pericortex in mature bones. Vascular and nonvascular porosities were not correlated. There were no secondary osteons in subadults. In adults, the highest secondary osteon population densities and lowest %ash occurred in the ventral-caudal, caudal, and cranial cortices, where shear strains, circumferential strain gradients, and fluid displacements are highest. Changes in thickness of the caudal cortex explained the largest proportion of the age-related increase in cranial-caudal breadth; the thickness of other cortices (dorsal, ventral, and cranial) exhibited smaller changes. Only subadult bones exhibited CFO patterns corresponding to habitual tension (ventral) and compression (dorsal). These CFO variations may be adaptations for differential mechanical requirements in "strain-mode-specific" loading. The more uniform oblique-to-transverse CFO patterns in adult bones may represent adaptations for shear strains produced by torsional loading, which is presumably more prevalent in adults. The micro- and ultrastructural heterogeneities may influence strain and fluid-flow dynamics, which are considered proximate signals in bone adaptation.

    View details for PubMedID 12808646

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