Bio

Clinical Focus


  • Orthopaedic Surgery
  • Foot/Ankle Trauma

Academic Appointments


Professional Education


  • Internship:UCI Medical Center (1987) CA
  • Board Certification: Orthopaedic Surgery, American Board of Orthopaedic Surgery (1995)
  • Fellowship:Roger Mann Foot and Ankle Surgery (1993) CA
  • Fellowship:Inselspital (1992) Switzerland
  • Residency:Howard University Hospital (1992) DC
  • Medical Education:UCI College of Medicine (1986) CA

Research & Scholarship

Current Research and Scholarly Interests


I am a Board Certified Orthopaedic Surgeon, subspecializing in Disorders of the Foot and Ankle. My clinic offers diagnosis and treatment of pain, deformity, and acute injuries of the foot and ankle.


My research interests include: rupture and tendinitis of the Achilles tendon, osteochondral defects of the talus, Total Ankle Arthroplasty, arthrodesis (fusion) of the foot and ankle, pain following operations of the foot and ankle, open fractures treated with operations, anatomy of the foot and

Teaching

2013-14 Courses


Publications

Journal Articles


  • 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

  • Increased Breast Cancer Prevalence Among Female Orthopedic Surgeons JOURNAL OF WOMENS HEALTH Chou, L. B., Chandran, S., Harris, A. H., Tung, J., Butler, L. M. 2012; 21 (6): 683-689

    Abstract

    As a result of low-dose ionizing radiation exposure during clinical practice, female orthopaedic surgeons may be at increased risk for breast cancer.The 2009 American Academy of Orthopaedic Surgeons (AAOS) membership directory was used to mail a survey to all female AAOS fellows. Survey responses were collected between June 2009 and June 2010 among 505 (69.7%) of the eligible women. We calculated standardized prevalence ratios (SPRs) and 95% confidence intervals (CIs) by dividing the observed number of cancers among female orthopaedic surgeons by the expected number, based on the gender-specific, age-specific, and race-specific cancer prevalence statistics in the general U.S. population. We compared the distribution of breast cancer risk factors in our study population to that of the women in the 2007 California Health Interview Survey (CHIS, n=30,541).Twenty-four women reported a prior diagnosis of invasive cancer. Female orthopaedic surgeons had a prevalence of cancer that was 85% higher than that of the general U.S. female population (SPR 1.85, 95% CI 1.19-2.76). Orthopaedic surgeons in our study also had a statistically significant 2.9-fold higher prevalence of breast cancer compared to the general U.S. female population (SPR 2.9, 95% CI 1.66-4.71). Survey respondents had a higher prevalence of both protective and predisposing breast cancer factors compared to California women.Our findings confirm that breast cancer prevalence is elevated among female orthopaedic surgeons. Although further research is needed to determine the factors behind this population's hypothesized increased risk, taken together, our results and others suggest that the orthopaedic community consider educating current practitioners of the use of protective shielding and other modifiable breast cancer risk factors.

    View details for DOI 10.1089/jwh.2011.3342

    View details for Web of Science ID 000305575100012

    View details for PubMedID 22432467

  • Supercharged Free Fibula for Complex Ankle Arthrodesis A Case Report ANNALS OF PLASTIC SURGERY Fox, P. M., Chou, L., Lee, G. K. 2012; 68 (4): 342-345

    Abstract

    We report the successful use of a supercharged free fibula for tibial reconstruction and ankle arthrodesis. A 28-year-old woman underwent resection of a giant cell tumor of the distal tibia and reconstruction using a methyl methacrylate cement spacer 12 years prior. The spacer eroded into her ankle joint causing significant pain with ambulation. Therefore, she required ankle arthrodesis but lacked distal tibia bone stock. The ipsilateral fibula was harvested for reconstruction and transferred on its distal blood supply into the bony tibial defect. The proximal blood supply of the fibula flap was then anastomosed to the posterior tibial vessels to supercharge the blood supply. An Ilizarov was placed for external fixation. The combination of a supercharged free fibula and stable external fixation for tibial reconstruction led to timely bony union and ambulation, as well as avoiding the potential complications that can occur with other reconstructive options.

    View details for DOI 10.1097/SAP.0b013e31824189d0

    View details for Web of Science ID 000301800600004

    View details for PubMedID 22421475

  • 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

  • Current Concepts Review: Intra-Articular Fractures of the Calcaneus FOOT & ANKLE INTERNATIONAL Epstein, N., Chandran, S., Chou, L. 2012; 33 (1): 79-86

    Abstract

    1) Intra-articular fractures of the calcaneus are associated with severe long-term consequences for function and pain. The condition of the soft tissues is of paramount importance when determining the method of treatment,the timing of surgery, and the post-injury rehabilitation.2) Intra-articular fractures are difficult to fully evaluate with plain radiographs. Computed tomography may assist in assessing the fracture pattern and planning for surgery. The likelihood of a good to excellent outcome is increased when an anatomic reduction is obtained.3) The outcome after operative management is difficult to characterize and appears to be influenced by factors related to the fracture, the patient, and the experience of the institution where the patient obtains treatment.All these factors should be factors in the decision to operate, but no single factor reliably determines the most appropriate treatment.4) Open reduction and internal fixation through an extensile approach achieves acceptable results in carefully selected patients. The use of a limited exposure with minimally invasive techniques may decrease the incidence of wound complications. However, this option is technically demanding and the quality of the reduction achieved may be more difficult to obtain and determine intraoperatively. Open fractures should be promptly debrided. The choice of fixation after reduction is based on the surgeons assessment of the soft tissue and the risk of infection.5) Post-traumatic arthritis of the subtalar joint is a common complication. Successful salvage can be achieved with a subtalar arthrodesis. However, these results may be influenced by the institution at which the initial management was rendered.

    View details for DOI 10.3113/FAI.2012.0079

    View details for Web of Science ID 000299500000013

    View details for PubMedID 22381241

  • Influence of Stretching and Warm-Up on Achilles Tendon Material Properties FOOT & ANKLE INTERNATIONAL Park, D. Y., Rubenson, J., Carr, A., Mattson, J., Besier, T., Chou, L. B. 2011; 32 (4): 407-413

    Abstract

    Controversy exists on stretching and warm-up in injury prevention. We hypothesized that warm up has a greater effect on Achilles tendon biomechanics than static stretching. This study investigated static stretching and warm-up on Achilles tendon biomechanics in recreational athletes, in vivo.Ten active, healthy subjects, 5 males, 5 females, With a mean age of 22.9 years with no previous Achilles tendon injuries were recruited. Typical stretching and warm-up routines were created. Testing was performed in a randomized cross-over design. A custom-built dynamometer was utilized to perform controlled isometric plantarflexion. A low profile ultrasound probe was utilized to visualize the musculotendinous junction of the medial gastrocnemius. An eight-camera motion capture system was used to capture ankle motion. Custom software calculated Achilles tendon biomechanics.Achilles tendon force production was consistent. No statistically significant differences were detected in stretch, stiffness, and strain between pre-, post-stretching, and post-warm-up interventions.Stretching or warm-up alone, and combined did not demonstrate statistically significant differences. Stretching and warm-up may have an equivalent effect on Achilles tendon biomechanics. Prolonged and more intense protocols may be required for changes to occur.Stretching and warm-up of the Achilles before exercise are commonly practiced. Investigating the effect of stretching and warm-up may shed light on potential injury prevention.

    View details for DOI 10.3113/FAI.2011.0407

    View details for Web of Science ID 000288979500015

    View details for PubMedID 21733444

  • Biomechanical Comparison of Blade Plate and Intramedullary Nail Fixation for Tibiocalcaneal Arthrodesis FOOT & ANKLE INTERNATIONAL Lee, A. T., Sundberg, E. B., Lindsey, D. P., Harris, A. H., Chou, L. B. 2010; 31 (2): 164-171

    Abstract

    Tibiocalcaneal arthrodesis is an uncommon salvage procedure used for complex problems of the ankle and hindfoot. A biomechanical evaluation of the fixation constructs of this procedure has not been studied previously. The purpose of this study was to compare intramedullary nail to blade plate fixation in a deformity model in fatigue endurance testing and load to failure.Nine matched pairs of fresh frozen cadaveric legs underwent talectomy followed by fixation with a blade plate and 6.5-mm fully threaded cancellous screw or an ankle arthrodesis intramedullary nail. The specimens were loaded to 270 N at a rate of 3 Hz for a total of 250,000 cycles, followed by loading to failure.Intramedullary nail fixation demonstrated greater mean stiffness throughout the fatigue endurance testing, from cycles 10 through 250,000 (blade plate versus intramedullary nail; cycle 10, 93 +/- 34 N/mm versus 117 +/- 40 N/mm (t = 2.33, p = 0.04); cycle 100, 89 +/- 34 N/mm versus 118 +/- 42 N/mm (t = 3.16, p = 0.01); cycle 1000, 86 +/- 32 N/mm versus 120 +/- 45 N/mm (t = 3.52, p = 0.01); cycle 10,000, 83 +/- 36 N/mm versus 128 +/- 50 N/mm (t = 3.80, p = 0.01); cycle 100,000, 82 +/- 34 N/mm versus 126 +/- 52 N/mm (t = 3.70, p = 0.01); cycle 250,000, 80 +/- 31 N/mm versus 125 +/- 49 N/mm (t = 4.2, p = 0.003). There was no statistically significant difference between the intramedullary nail and blade plate fixation in cycle one or in load to failure; cycle 10, blade plate 70 +/- 38 N/mm and intramedullary nail 67 +/- 20 N/mm (t = 0.60, p = 0.56); load to failure, blade plate 808 +/- 193 N, IMN 1074 +/- 290 N) (p = 0.15).Intramedullary nail fixation was biomechanically superior to blade plate and screw fixation in a tibiocalcaneal arthrodesis construct.The ankle arthrodesis intramedullary nail provides greater stiffness for fixation in tibiocalcaneal arthrodesis, which may improve healing.

    View details for DOI 10.3113/FAI.2010.0164

    View details for Web of Science ID 000274179100011

    View details for PubMedID 20132755

  • Prevalence of Cancer in Female Orthopedic Surgeons in the United States JOURNAL OF BONE AND JOINT SURGERY-AMERICAN VOLUME Chou, L. B., Cox, C. A., Tung, J. J., Harris, A. H., Brooks-Terrell, D., Sieh, W. 2010; 92A (1): 240-244
  • Tumors of the Foot and Ankle: Experience with 153 Cases FOOT & ANKLE INTERNATIONAL Chou, L. B., Ho, Y. Y., Malawer, M. M. 2009; 30 (9): 836-841

    Abstract

    Both primary and metastatic tumors in the foot and ankle have been reported as rare. The purpose of this study was to describe 153 cases of foot and ankle tumors from a 20-year experience in a tertiary referral center specializing in orthopaedic oncology. It is the largest reported series of both bone and soft tissue tumors in the foot and ankle.Between 1986 and 2006, a retrospective chart review was performed of a total of 2,660 tumors surgically treated in all anatomic sites by a single surgeon at a musculoskeletal tumor referral center.One hundred fifty-three patients (5.75%) with bone and/or soft tissue tumors of the foot and ankle were treated. There were 84 women and 69 men. The patients' ages ranged from 1 to 84, with a median age of 30 and mean of 33.2. The tissue types included 80 soft tissue and 73 bone tumors. Overall, 60 (39.2%) were malignant, and 93 (60.8%) were benign. The most common diagnosis was giant cell tumor. In addition, giant cell tumor was the most common bone tumor, while pigmented villonodular synovitis and giant cell tumor of the tendon sheath were the most common soft tissue tumors.The incidence of tumors of the foot and ankle in this series of a single surgeon over a 20-year practice was 5.75%. The results of this study reaffirm that awareness, correctly diagnosing, and appropriately treating or referring to an orthopaedic oncologist may help with an improved outcome for patients.

    View details for DOI 10.3113/FAI.2009.0836

    View details for Web of Science ID 000269787600004

    View details for PubMedID 19755066

  • Current Concept Review: Perioperative Soft Tissue Management for Foot and Ankle Fractures FOOT & ANKLE INTERNATIONAL Chou, L. B., Lee, D. C. 2009; 30 (1): 84-90

    View details for DOI 10.3113/FAI.2009.0084

    View details for Web of Science ID 000262156500017

    View details for PubMedID 19176194

  • Postoperative Pain Following Foot and Ankle Surgery: A Prospective Study FOOT & ANKLE INTERNATIONAL Chou, L. B., Wagner, D., Witten, D. M., Martinez-Diaz, G. J., Brook, N. S., Toussaint, M., Carroll, I. R. 2008; 29 (11): 1063-1068

    Abstract

    Orthopaedic procedures have been reported to have the highest incidence of pain compared to other types of operations. There are limited studies in the literature that investigate postoperative pain.A prospective study of 98 patients undergoing orthopedic foot and ankle operations was undertaken to evaluate their pain experience. A Short-Form McGill Pain Questionnaire (SF-MPQ) was administered preoperatively and postoperatively.The results showed that patients who experienced pain before the operation anticipated feeling higher pain intensity immediately postoperatively. Patients, on average, experienced higher pain intensity 3 days after the operation than anticipated. The postoperative pain intensity at 3 days was the most severe, while postoperative pain intensity at 6 weeks was the least severe. Age, gender and preoperative diagnosis (acute versus chronic) did not have a significant effect on the severity of pain that patients experienced. Six weeks following the operation, the majority of patients felt no pain. In addition, the severity of preoperative pain was highly predictive of their anticipated postoperative pain and 6-week postoperative pain, and both preoperative pain and anticipated pain predict higher immediate postoperative pain.The intensity of patients' preoperative pain was predictive of the anticipated postoperative pain. Patients' preoperative pain and anticipated postoperative pain were independently predictive of the 3-day postoperative pain. The higher pain intensity a patient experienced preoperatively suggested that their postoperative pain severity would be greater. Therefore, surgeons should be aware of these findings when treating postoperative pain after orthopaedic foot and ankle operations.

    View details for DOI 10.3113/FAI.2008.1063

    View details for Web of Science ID 000260714000002

    View details for PubMedID 19026197

  • Variation of nerve to flexor hallucis brevis FOOT & ANKLE INTERNATIONAL Chou, L. B., Choi, L. E., Ramachandra, T., Ma, G. 2008; 29 (10): 1042-1044

    Abstract

    Hallopeau's nerve is a branch of the lateral plantar nerve that supplies the flexor hallucis brevis muscle while also forming an anastomosis with the medial plantar nerve. In this study, the presence of this neural anastomosis was determined through dissection of cadaveric specimens.Twenty-six fresh-frozen adult feet (13 matched pairs) were dissected to assess the presence or absence of Hallopeau's nerve.Dissections revealed four out of 26 specimens had this anastomosis.This study confirms this anatomic variation.The clinical significance of these anastomoses remains unknown. These anastomoses are analogous to some in the hand and forearm.

    View details for DOI 10.3113/FAI.2008.1042

    View details for Web of Science ID 000259719800013

    View details for PubMedID 18851823

  • Biomechanical comparison of the simple running and cross-stitch epitenon sutures in Achilles tendon repairs FOOT & ANKLE INTERNATIONAL Shepard, M. E., Lindsey, D. P., Chou, L. B. 2008; 29 (5): 513-517

    Abstract

    Augmenting the strength of Achilles tendon repairs may allow for earlier active rehabilitation with less risk of adhesion formation and re-ruptures, leading to quicker and stronger healing. Building upon previous research that has (1) demonstrated strength gains in Achilles repairs upon addition of simple running epitenon sutures, and (2) shown the cross-stitch epitenon suture to be stronger than the simple running stitch in flexor tendons of the hand, this study compares use of these epitenon sutures in the Achilles tendon.Ruptures were simulated in 7 matched pairs of fresh frozen human Achilles tendons and repaired with the two-tailed Krakow locking loop core technique using No. 2 nonabsorbable, braided, polyester suture. From each pair, one specimen was randomly selected to also receive the epitenon cross-stitch, the other receiving the simple running stitch. All epitenon repairs employed 4-0 nylon suture. Repaired tendons were loaded in tension to the point of failure on a Materials Testing Machine (MTS).Tendon repair augmented with the cross-stitch displayed a significant, 53% greater failure strength than those repaired with the simple running stitch. Increases in initial stiffness and resistance to 2-mm gap formation in the cross-stitch specimens were 3.1% and 3.6%, respectively.Gapping resistance and initial stiffness in Achilles tendon repairs were comparable between the cross-stitch and simple running stitch, but the cross-stitch significantly improved failure strength.Greater failure strength may translate clinically to lower rates of re-rupture and earlier mobilization following Achilles tendon repair.

    View details for DOI 10.3113/FAI.2008.0513

    View details for Web of Science ID 000255408900013

    View details for PubMedID 18510906

  • Osteoarthritis of the ankle: The role of arthroplasty JOURNAL OF THE AMERICAN ACADEMY OF ORTHOPAEDIC SURGEONS Chou, L. B., Coughlin, M. T., Hansen, S., Haskell, A., Lundeen, G., Saltzman, C. L., Mann, R. A. 2008; 16 (5): 249-259

    Abstract

    Total ankle arthroplasty was developed to reduce pain and retain motion of the ankle joint in patients with osteoarthritis. The ankle joint has unique, complex anatomic and biomechanical characteristics that must be considered in a successful total ankle arthroplasty prosthesis. Initial designs from the 1960s to the 1970s had many failures. Current designs use two or three components, and recent reports on total ankle arthroplasty show consistent good to excellent intermediate clinical results, with up to 90% decreased pain and high patient satisfaction. The follow-up time of these studies is limited, however, and long-term studies with 10- to 15-year follow-ups are needed. Also, a wide variety of complications has been reported, including osteomyelitis and osteolysis. To limit the number of complications and improve clinical outcome of total ankle arthroplasty, careful patient selection and surgeon experience are important.

    View details for Web of Science ID 000255419100003

    View details for PubMedID 18460685

  • Secretan's disease of the foot: A case report and review FOOT & ANKLE INTERNATIONAL Abnousi, F., Chou, L. B. 2008; 29 (2): 248-250

    Abstract

    Secretan's disease is a rare disorder that has, to date, only been reported in the hand. After minor trauma, edema and hyperplasia of the hand may result, and pathological evaluation demonstrates thick fibrous tissue. We present the first report of Secretan's disease involving the foot in a 15-year-old athletic teenage girl with a remote history of blunt trauma, and review the relevant literature.

    View details for DOI 10.3113/FAI.2008.0248

    View details for Web of Science ID 000252829000022

    View details for PubMedID 18315985

  • Current concepts review: Venous thromboembolic disease in foot and ankle surgery FOOT & ANKLE INTERNATIONAL Mayle, R. E., DiGiovanni, C. W., Lin, S. S., Tabrizi, P., Chou, L. B. 2007; 28 (11): 1207-1216

    View details for DOI 10.3113/FAI.2007.1207

    View details for Web of Science ID 000250660200017

    View details for PubMedID 18021595

  • Biomechanical testing of epitenon suture strength in Achilles tendon repairs FOOT & ANKLE INTERNATIONAL Shepard, M. E., Lindsey, D. P., Chou, L. B. 2007; 28 (10): 1074-1077

    Abstract

    Recent evidence that early, active mobilization protocols after Achilles tendon repairs increase recovery speed and strength make operative repair strength critical to positive outcomes after Achilles tendon ruptures. While previous research has focused on core (tendon proper) repair techniques, no previous literature has reported testing of core repairs augmented with epitenon sutures, which have been shown to increase the strength of repairs of flexor tendons of the hand.Five matched pairs of fresh frozen human Achilles tendons were tested with and without the addition of an epitenon suture to the core repair suture. All specimens were repaired using a No. 2 Ethibond Krakow locking loop core suture. The epitenon suture was added to one tendon randomly chosen from each pair, using a 4-0 nylon suture. All specimens were mounted on an MTS testing machine (MTS Systems Corp., Eden Prairie, MN) and loaded to failure, which was defined as a 1-cm gap formation.The addition of epitenon sutures significantly increased the force necessary to produce a 2-mm gap as compared to core sutures alone by 74%, and it increased the average load to failure by 119%. Also, initial tendon stiffness was 173% greater in tendons reinforced with epitenon sutures.This study demonstrates that greater resistance to gap formation, approximation of tissue ends, and tensile strength were achieved by the addition of an epitenon suture. Clinical relevance may improve healing by decreased gap formation at the repair site and a lower risk of adhesion formation.

    View details for DOI 10.3113/FAI.2007.1074

    View details for Web of Science ID 000250072100009

    View details for PubMedID 17923058

  • Osteosarcoma of the calcaneus treated with prosthetic replacement with twelve years of followup: A case report FOOT & ANKLE INTERNATIONAL Chou, L. B., Malawer, M. M. 2007; 28 (7): 841-844

    View details for DOI 10.3113/FAI.2006.0841

    View details for Web of Science ID 000247849200012

    View details for PubMedID 17666179

  • Treatment of severe, painful pes planovalgus deformity with hindfoot arthrodesis and wedge-shaped tricortical allograft FOOT & ANKLE INTERNATIONAL Chou, L. B., Halligan, B. W. 2007; 28 (5): 569-574

    Abstract

    This study tested the hypothesis that modification of the standard technique of hindfoot arthrodesis with the use of a wedge-shaped tricortical allograft would improve the amount of correction of pes planovalgus deformity. The results were compared to previous reports.Between 1998 and 2005, the senior author (LBC) performed 13 hindfoot arthrodeses on 12 patients using an allograft to improve correction of the deformity for severe, painful pes planovalgus deformity. The average patient age was 55 (range 27 to 77) years. There were seven women and five men. The indications were posterior tibial tendon dysfunction (seven feet), rheumatoid arthritis (three feet), post-traumatic arthritis and deformity (one foot), congenital pes planovalgus (one foot), and tarsal coalition (one foot).Twelve of 13 feet achieved union by 12 weeks postoperatively. There was one nonunion. The average time to fusion was 12 weeks. All 12 patients were satisfied with the results of the operation. The average postoperative American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot score was 87 points, and the AOFAS Midfoot score was 85 points. Preoperative and postoperative radiographs were compared to evaluate correction of deformity. On lateral weightbearing views, the talo-first metatarsal angle improved from 15 to 6 degrees, and the lateral talocalcaneal angle improved from 48 to 35 degrees. On anteroposterior views, the talo-first metatarsal angle improved from 17 to 7 degrees, the talonavicular coverage decreased from 28 to 13 degrees, and the talocalcaneal angle improved from 23 to 13 degrees.A simple modification of the addition of allograft to a common procedure of hindfoot arthrodesis to treat severe, painful pes planovalgus results is reliable and offers satisfactory correction.

    View details for DOI 10.3113/FAI.2007.0569

    View details for Web of Science ID 000246405400007

    View details for PubMedID 17559763

  • Stress fracture as a complication of autogenous bone graft harvest from the distal tibia FOOT & ANKLE INTERNATIONAL Chou, L. B., Mann, R. A., Coughlin, M. J., McPeake, W. T., Mizel, M. S. 2007; 28 (2): 199-201

    Abstract

    Autogenous bone graft from the distal tibia provides cancellous bone graft for foot and ankle operations, and it has osteogenic and osteoconductive properties. The site is in close proximity to the foot and ankle, and published retrospective studies show low morbidity from the procedure.One-hundred autografts were obtained from the distal tibia between 2000 and 2003. In four cases the distal tibial bone graft harvest resulted in a stress fracture. There were three women and one man.The average time of diagnosis of the stress fracture from the operation was 1.8 months. All stress fractures healed with a short course (average 2.4 months) of cast immobilization.This study demonstrated that a stress fracture from the donor site of autogenous bone graft of the distal tibia occurs and can be successfully treated nonoperatively.

    View details for DOI 10.3113/FAI.2007.0199

    View details for Web of Science ID 000244044000011

    View details for PubMedID 17296139

  • Surgical treatment of severe hallux valgus: The state of practice among academic foot and ankle surgeons FOOT & ANKLE INTERNATIONAL Pinney, S. J., Song, K. R., Chou, L. B. 2006; 27 (12): 1024-1029

    Abstract

    The purpose of this study was to evaluate the operative procedures used for treatment of severe hallux valgus by academic foot and ankle surgeons practicing in the United States.A patient with severe hallux valgus deformity was developed as a hypothetical case: a 50-year-old woman with a severe deformity (intermetatarsal angle = 20 degrees; hallux valgus angle = 42 degrees). The patient was symptomatic with pain, did not improve with conservative measures, and wanted the deformity corrected. This case was sent to academic foot and ankle surgeons in a survey to determine their preferred operative treatment for this case. The overall response rate was 84% (128 of 153). To be included in the study group each surgeon had to have 1) foot and ankle patients comprising 50% or more of his clinical practice and 2) direct responsibility for teaching orthopaedic residents. One hundred and five respondents met the inclusion criteria and formed the study group; however, three surveys with invalid responses were deleted.Fifty-two percent (54 of 102) of the respondents chose a metatarsal osteotomy, 26% (26 of 102) a first metatarsophalangeal (MTP) joint arthrodesis, and 24% (24 of 102) a Lapidus procedure. Two respondents chose both an arthrodesis and a metatarsal osteotomy. Among the 54 respondents who chose metatarsal osteotomies, 24 used a Ludloff, 16 a proximal crescentic, eight a proximal chevron, two a scarf, two a distal chevron, and two other. In addition, secondary procedures to enhance the correction included a Weil osteotomy in 46% (47 of 102) and an Akin osteotomy in 30% (31 of 102).There was a wide variation in the type of procedure used to correct this severe hallux valgus deformity; approximately 50% of the respondents chose a metatarsal osteotomy, 25% chose a first MTP joint arthrodesis, and 25% a Lapidus procedure.

    View details for Web of Science ID 000242832400004

    View details for PubMedID 17207427

  • Surgical treatment of mild hallux valgus deformity: The state of practice among academic foot and ankle surgeons FOOT & ANKLE INTERNATIONAL Pinney, S., Song, K., Chou, L. 2006; 27 (11): 970-973

    Abstract

    The purpose of this study was to determine the operative procedure of choice among academic foot and ankle surgeons practicing in the United States for treatment of mild hallux valgus deformity.A hypothetical patient was created: a 60-year-old woman with a mild hallux valgus deformity (first intermetatarsal angle of 11 degrees and hallux valgus angle of 22 degrees). The patient complained of pain around the bunion, nonoperative treatment had failed, and she desired operative correction. The case was sent to academic foot and ankle surgeons to identify their operative treatment of choice. The overall response rate was 83.7% (128 of 153). To be included in the study group each surgeon had 1) foot and ankle patients comprising 50% or more of their clinical practice and 2) direct responsibility for teaching orthopaedic surgery residents. One hundred and three respondents met the inclusion criteria and formed the study group.Eighty-seven percent (90 of 103) reported that they would use a distal chevron osteotomy as their primary procedure to correct the mild hallux valgus. Ten percent (10 of 103) reported that they would also add an Akin osteotomy of the proximal phalanx to enhance correction.Most respondents chose a distal chevron osteotomy as their primary procedure to correct the mild hallux valgus deformity.

    View details for Web of Science ID 000241674200018

    View details for PubMedID 17144962

  • Current concepts review: Lisfranc injuries FOOT & ANKLE INTERNATIONAL Desmond, E. A., Chou, L. B. 2006; 27 (8): 653-660

    View details for Web of Science ID 000239753000019

    View details for PubMedID 16919225

  • Synovial sarcoma presenting as posterior tibial tendon dysfunction: A report of two cases and review of the literature FOOT & ANKLE INTERNATIONAL Chou, L. B., Malawer, M. M. 2004; 25 (11): 810-814

    View details for Web of Science ID 000225072000011

    View details for PubMedID 15574241

  • Functional evaluation of the Scandinavian Total Ankle Replacement FOOT & ANKLE INTERNATIONAL Dyrby, C., Chou, L. B., Andriacchi, T. P., Mann, R. A. 2004; 25 (6): 377-381

    Abstract

    The purpose of this study was to evaluate the function of the ankle joint during walking before and after Scandinavian Total Ankle Replacement (STAR). Nine patients (six males and three females) with an average age of 65 years, scheduled for unilateral total ankle replacement for osteoarthritis and rheumatoid arthritis, were evaluated both preoperatively and postoperatively in a gait analysis laboratory. Arthroplasty patients showed reduced range of motion at the ankle compared to normal controls. Postoperative arthroplasty subjects had significantly improved external ankle dorsiflexion moment, the moment that affects the plantarflexor muscles, when compared to their preoperative status. The moment in arthroplasty patients was increased, indicating improved function of the ankle joint.

    View details for Web of Science ID 000223885900002

    View details for PubMedID 15215020

  • Autologous osteochondral grafting for talar cartilage defects FOOT & ANKLE INTERNATIONAL Al-Shaikh, R. A., Chou, L. B., Mann, J. A., Dreeben, S. M., Prieskorn, D. 2002; 23 (5): 381-389

    Abstract

    The purpose of this study was to evaluate the clinical results of Osteochondral Autograft Transfer System (OATS) for the treatment of symptomatic osteochondral defects of the talus using standardized outcome analysis. Nineteen patients with symptomatic osteochondral defect (OCD) of the talus were treated with autologous osteochondral grafting. There were six men and 13 women. The average age was 32 years (range, 18 to 48 years). The average duration of symptoms prior to surgery was 4.2 years (range, three months to 12 years). All patients had failed nonoperative treatment, and 13 (68%) patients had failed prior excision, curettage and/or drilling of the lesion. The average size of the lesion prior to autografting was 12 mm x 10 mm (range, 10 x 5 mm to 20 x 20 mm). Donor plugs were harvested from the trochlear border of the ipsilateral femoral condyle. Ankle exposure was obtained with a medial malleolar osteotomy in 13 patients, arthrotomy in five patients and lateral malleolar osteotomy in one patient. Clinical evaluations were performed for both the recipient ankle and donor knee using the AOFAS Ankle/Hindfoot Scale and Lysholm knee scale, respectively. The average follow-up time was 16 months (range, 12 to 30 months). The average postoperative AOFAS ankle score was 88 (range, 60 to 100). Most patients had occasional mild pain, but excellent function, range of motion, stability and alignment. The average postoperative ankle score for the 13 patients who failed prior surgery was 91 (range, 84 to 100). The average postoperative Lysholm knee score was 97 (range, 87 to 100). Only two patients had mild knee pain. Postoperative radiographs were available for 13 patients. There was no evidence of graft subsidence and all grafts healed. All malleolar osteotomies united. Seventeen (89%) patients said that they would undergo the procedure again. The results of osteochondral autograft transplant for OCD lesions of the talus demonstrate excellent postoperative ankle scores including improvement of pain and function with minimal knee donor site morbidity. Also, our results indicate that this is an effective salvage procedure following failed previous procedures and for patients with longstanding symptoms.

    View details for Web of Science ID 000175663900002

    View details for PubMedID 12043980

  • Intramedullary screw fixation of proximal fifth metatarsal fractures: A biomechanical study FOOT & ANKLE INTERNATIONAL Shah, S. N., Knoblich, G. O., Lindsey, D. P., Kreshak, J., Yerby, S. A., Chou, L. B. 2001; 22 (7): 581-584

    Abstract

    Intramedullary screw fixation is a popular technique for treatment of proximal fifth metatarsal fractures. The purpose of this study was to compare the fixation rigidity of a 5.5 mm partially threaded cannulated titanium screw, with presumed superior endosteal purchase, to a similar 4.5 mm screw. Acute fifth metatarsal fractures were simulated in cadavers, stabilized with intramedullary screws, and loaded to failure in three-point bending. The initial failure loads for the metatarsals fixed with 4.5 mm and 5.5 mm screws were not significantly different (332.4 N vs. 335.2 N, respectively), nor were the ultimate failure loads (849.8 N vs. 702.2 N, respectively). Based upon our results, maximizing screw diameter does not appear to be critical for fixation rigidity and may increase the risk of intraoperative or postoperative fracture.

    View details for Web of Science ID 000170686700009

    View details for PubMedID 11503984

  • Lateral planter nerve entrapment in a competitive gymnast CLINICAL JOURNAL OF SPORT MEDICINE Fredericson, M., Standage, S., Chou, L., Matheson, G. 2001; 11 (2): 111-114

    View details for Web of Science ID 000169055800008

    View details for PubMedID 11403110

  • Tibiotalocalcaneal arthrodesis FOOT & ANKLE INTERNATIONAL Chou, L. B., Mann, R. A., Yaszay, B., Graves, S. C., McPeake, W. T., Dreeben, S. M., Horton, G. A., Katcherian, D. A., Clanton, T. O., MILLER, R. A., Van Manen, J. W. 2000; 21 (10): 804-808

    Abstract

    The purpose of this multicenter retrospective study of 55 patients (56 ankles) who underwent simultaneous tibiotalocalcaneal arthrodesis with severe disease involving the ankle and subtalar joints was to determine improvement of pain and function. The surgical indications included osteoarthritis, posttraumatic injury, failed previous surgery, talar avascular necrosis, osteoarthritis, and rheumatoid arthritis involving the ankle and subtalar joints. The average age at the time of the operation was 53 years. The average time of follow-up was 26 months after the operation. Fusion was achieved in 48 ankles, with an average time of fusion of 19 weeks. Forty-eight of the 55 patients were satisfied with the procedure. The average leg length discrepancy was 1.4 cm. The average amount of dorsiflexion was 2 degrees and plantar flexion was 5 degrees. Following surgery, 42 patients complained of pain, 40 patients required shoe modification or an orthotic device, and 34 patients had a limp. Fourteen patients described their activity as unlimited. Based on the AOFAS evaluation, the patients scored an average of 66 on the ankle-hind foot scale following surgery. The most common complications were nonunion (8 ankles) and wound infection (6 ankles). This study demonstrates that tibiotalocalcaneal arthrodesis is an effective salvage procedure for patients with disease both involving the ankle and subtalar joints.

    View details for Web of Science ID 000090046800002

    View details for PubMedID 11128009

  • Disorders of the first metatarsophalangeal joint - Diagnosis of great-toe pain PHYSICIAN AND SPORTSMEDICINE Chou, L. B. 2000; 28 (7): 32-?

    Abstract

    Disorders of the joint at the base of the hallux are common in active patients. Great-toe sprains (turf toe) can range from mild to severe with associated fractures. Hallux rigidus, a painful flexion deformity, is often seen in athletes who stress the joint repetitively. Heredity may predispose athletes to hallux valgus (bunion) but improper footwear, injury, and hyperpronation can also be implicated. Weight-bearing activities, climbing stairs, or wearing high-heeled shoes will aggravate sesamoiditis. Stress fractures, osteochondral defects, and gout are other causes of toe pain. X-rays are essential for accurate diagnosis. Nonoperative measures can reduce pain, but surgery is an option for recalcitrant cases.

    View details for Web of Science ID 000087959000010

    View details for PubMedID 20086649

  • Biplanar chevron osteotomy FOOT & ANKLE INTERNATIONAL Chou, L. E., Mann, R. A., Casillas, M. M. 1998; 19 (9): 579-584

    Abstract

    We retrospectively reviewed the results of using a biplanar chevron osteotomy performed on patients who presented with hallux valgus deformities with an increased distal metatarsal articular angle (DMAA). The study included 17 feet (14 patients) of 12 women and 2 men. The average follow-up was 33 months. The average American Orthopaedic Foot and Ankle Society Hallux Metatarsophalangeal-Interphalangeal Clinical Rating Score was 91. Ten of the 14 patients (13 of 17 feet) stated that they would choose to undergo the procedure again. The hallux valgus angle was improved from an average of 22 degrees to 18 degrees, the intermetatarsal angle from 11 degrees to 9 degrees, and the DMAA from 16 degrees to 9 degrees. We have demonstrated this procedure to be useful in the treatment of symptomatic bunion deformities with an increased DMAA.

    View details for Web of Science ID 000075995400002

    View details for PubMedID 9763161

  • Prosthetic replacement for intramedullary calcaneal osteosarcoma: A case report FOOT & ANKLE INTERNATIONAL Chou, L. B., Malawer, M. M., Kollender, Y., Wellborn, C. C. 1998; 19 (6): 411-415

    View details for Web of Science ID 000074288900012

    View details for PubMedID 9677086

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