Jeremy Chan

All Publications

• Orthotic Devices for the Foot and Ankle. The Journal of the American Academy of Orthopaedic Surgeons An, T. W., Berke, G., Beattie, W., Chan, J. Y. 2023

  Abstract

  Millions of Americans wear ankle-foot orthotic devices for protection, pain relief, and deformity correction. Inquiries about off-the-shelf and custom devices are a common reason for evaluation with a foot and ankle surgeon or general orthopaedic surgeon. Despite limited high-quality evidence for their use, these devices can have a notable clinical impact on physical function. An up-to-date understanding of orthotic device options and their appropriate use in managing musculoskeletal pathologies applies to all orthopaedic providers. This review aims to categorize orthosis types and provide specific device recommendations for common adult conditions such as flatfoot, cavovarus foot, and ankle instability. Collaboration with a certified orthotist can help patients achieve functional and recreational goals with the use of appropriately designed and applied orthoses.

  View details for DOI 10.5435/JAAOS-D-23-00832

  View details for PubMedID 38109744

• Evaluation and Management of Adult Footdrop JOURNAL OF THE AMERICAN ACADEMY OF ORTHOPAEDIC SURGEONS Haupt, E. T., Chan, J. Y., Michalski, M., Thordarson, D. B. 2022; 30 (16): 747-756

  Abstract

  Footdrop is a common musculoskeletal condition defined by weakness in ankle joint dorsiflexion. Although the etiology varies, footdrop is characterized by specific clinical and gait abnormalities used by the patient to overcome the loss of active ankle dorsiflexion. The condition is often associated with deformity because soft-tissue structures may become contracted if not addressed. Patients may require the use of special braces or need surgical treatment to address the notable level of physical dysfunction. Surgical treatment involving deformity correction to recreate a plantigrade foot along with tendon transfers has been used with notable success to restore a near-normal gait. However, limitations and postoperative dorsiflexion weakness have prompted investigation in nerve transfer as a possible alternative surgical treatment.

  View details for DOI 10.5435/JAAOS-D-21-00717

  View details for Web of Science ID 000837793500002

  View details for PubMedID 36067460

• Research methodologic quality varies significantly by subspecialty: An analysis of AAOS meeting abstracts. Journal of clinical orthopaedics and trauma Souza, K. E., Chan, J. Y., Campbell, S. T., Bishop, J. A. 2021; 15: 37–41

  Abstract

  Background: The purpose of this study was to compare the level of evidence and study type of clinical abstracts accepted to the 2017 AAOS Annual Meeting based on subspecialty.Methods: All clinical abstracts presented at the 2017 AAOS Annual Meeting were assessed by two independent raters for LOE and study type. Nonparametric statistics and chi-square test were used to compare LOE and study types between subspecialties.Results: A total of 1083 abstracts met inclusion criteria. There was a significant difference in LOE of abstracts by subspecialty (p<0.001). Shoulder/elbow, adult reconstruction knee, hand/wrist, and sports had the highest percentage of level I and II studies. The type of study also varied significantly by subspecialty (p=0.005).Discussion: Methodologic quality of clinical studies presented at the 2017 AAOS Annual Meeting differed significantly among subspecialties. Orthopedic researchers should look to the fields producing the highest quality studies in an effort to improve methodological quality.

  View details for DOI 10.1016/j.jcot.2020.11.001

  View details for PubMedID 33717914

• Analysis of Orthopaedic Job Availability in the United States Based on Subspecialty. Journal of the American Academy of Orthopaedic Surgeons. Global research & reviews Chan, J. Y., Charlton, T. P., Thordarson, D. B. 2020; 4 (11): e20.00195

  Abstract

  The number of orthopaedic residency graduates pursuing additional subspecialty training has increased along with the percentage of advertised jobs requiring fellowship. As such, the implications of fellowship training on job availability and marketability may impact their choice of subspecialty. The purpose of this study was to evaluate job availability in the United States for general orthopaedics and orthopaedic subspecialties.Job advertisements in 2019 were reviewed from the career center databases of the Journal of Bone and Joint Surgery, American Academy of Orthopaedic Surgeons, as well as of individual subspecialty societies. Job listings were cross referenced to identify unique jobs within the United States, which were categorized by the orthopaedic training required, practice type, and location. To assess job availability, a ratio of fellows to job listings was calculated based on the number of matched candidates for nine subspecialty fellowships and the number of residency graduates entering general practice in 2019.A total of 466 unique job listings were identified with 114 generalist and 352 subspecialist positions. The subspecialties with the lowest number of fellows per advertised job were foot and ankle (1.1), adult reconstruction (2.0), and trauma (2.1). The subspecialties with the highest number of fellows per advertised job were sports medicine (6.3), shoulder and elbow (5.8), and oncology (5.7). Job availability for general orthopaedics was higher than for any subspecialty. The highest percentage of positions advertised were hospital employed jobs compared with private practice and academic positions.Job availability for fellowship graduates varies notably based on orthopaedic subspecialty. At this time, generalists and subspecialists trained in foot and ankle, adult reconstruction, and trauma seem to be in greatest demand. The reason for the differences in demand is likely multifactorial. Our findings should be considered by orthopaedic residents pursuing fellowship training in addition to weighing both personal interest and financial considerations in their subspecialty choice.

  View details for DOI 10.5435/JAAOSGlobal-D-20-00195

  View details for PubMedID 33986211

• Distal Chevron Osteotomy Increases Anatomic Intermetatarsal Angle in Hallux Valgus. Foot & ankle orthopaedics Chan, J. Y., Noori, N., Chen, S., Pfeffer, G. B., Charlton, T. P., Thordarson, D. B. 2020; 5 (4): 2473011420960710

  Abstract

  Distal chevron metatarsal osteotomy (DCO) is a common technique to address hallux valgus (HV), which involves coronal translation of the capital fragment resulting in a nonanatomic first metatarsal. The purpose of this study was to evaluate the radiographic effect of the DCO on the anatomic vs the mechanical axis of the first metatarsal. Our hypothesis was that patients undergoing DCO would have improvement in the mechanical metatarsal axis but worsening of the anatomic axis.This was a retrospective case series of consecutive patients who underwent DCO for HV. The primary outcomes were the change in anatomic first-second intermetatarsal angle (a1-2IMA) vs mechanical first-second intermetatarsal angle (m1-2IMA). Secondary outcomes included the change in hallux valgus angle (HVA) and medial sesamoid position.40 feet were analyzed with a mean follow-up of 21.2 weeks. The a1-2IMA increased significantly (mean, 4.1 degrees) whereas the m1-2IMA decreased significantly (mean, 4.6 degrees) following DCO. There was a significant improvement in HVA (mean, 12.5 degrees). Medial sesamoid position was improved in 21 feet (52.5%). Patients with no improvement in sesamoid position were found to have a larger increase in a1-2IMA (mean, 4.7 vs 3.5 degrees, P = .03) and less improvement in m1-2IMA (mean, 3.8 vs 5.2 degrees, P = .02) compared to patients with improvement in sesamoid position.Distal chevron osteotomy for HV was associated with worsening of the anatomic axis of the first metatarsal despite improvements in the mechanical metatarsal axis, HVA, and medial sesamoid position. Greater worsening of the anatomic axis was associated with less improvement of sesamoid position. Our findings may suggest the presence of intermetatarsal instability, which could limit the power of DCO in HV correction for more severe deformities and provide a mechanism for HV recurrence.Level IV, retrospective case series.

  View details for DOI 10.1177/2473011420960710

  View details for PubMedID 35097412

  View details for PubMedCentralID PMC8702972

• Optimizing the Orthopaedic Medical Student Rotation: Keys to Success for Students, Faculty, and Residency Programs. The Journal of the American Academy of Orthopaedic Surgeons Campbell, S. T., Chan, J. Y., Gardner, M. J., Bishop, J. A. 2019

  Abstract

  Senior medical students interested in pursuing careers in orthopaedic surgery participate in orthopaedic rotations around the country. These rotations are an important part of the application process because they allow students to demonstrate their work ethic and knowledge and learn more about the fit and culture of the residency program. Although knowledge and technical ability are important, several less tangible factors also contribute to success. These include maintaining situational awareness and a positive attitude, putting forth an appropriate effort, preparing effectively, and critically evaluating one's own performance. Attention to these details can help maximize the student's chance for a successful rotation. The hosting program and faculty can further facilitate a successful rotation by setting appropriate expectations, orienting the student to the program, carefully selecting appropriate services and faculty, and providing dedicated education to the student.

  View details for DOI 10.5435/JAAOS-D-19-00096

  View details for PubMedID 31136321

• Kohler Disease: Avascular Necrosis in the Child. Foot and ankle clinics Chan, J. Y., Young, J. L. 2019; 24 (1): 83–88

  Abstract

  Kohler disease is a childhood condition of pain and swelling of the medial midfoot with associated osteochondrosis or avascular necrosis of the tarsal navicular. The age at presentation is between 2 and 10 years, with boys more likely to be affected than girls. Radiographs show increased sclerosis and sometimes flattening and fragmentation of the navicular. Long-term outcomes for Kohler disease are favorable regardless of the type of treatment, although a short period of immobilization with a short leg walking cast may reduce the duration of symptoms.

  View details for PubMedID 30685015

• Lower Complication Rate Following Ankle Fracture Fixation by Orthopaedic Surgeons Versus Podiatrists. The Journal of the American Academy of Orthopaedic Surgeons Chan, J. Y., Truntzer, J. N., Gardner, M. J., Bishop, J. A. 2018

  Abstract

  INTRODUCTION: Increased overlap in the scope of practice between orthopaedic surgeons and podiatrists has led to increased podiatric treatment of foot and ankle injuries. However, a paucity of studies exists in the literature comparing orthopaedic and podiatric outcomes following ankle fracture fixation.METHODS: Using an insurance claims database, 11,745 patients who underwent ankle fracture fixation between 2007 and 2015 were retrospectively evaluated. Patient data were analyzed based on the provider type. Complications were identified by the International Classification of Diseases, Ninth Revision, codes, and revision surgeries were identified by the Current Procedural Terminology codes. Complications analyzed included malunion/nonunion, infection, deep vein thrombosis, and rates of irrigation and debridement. Risk factors for complications were compared using the Charlson Comorbidity Index.RESULTS: Overall, 11,115 patients were treated by orthopaedic surgeons and 630 patients were treated by podiatrists. From 2007 to 2015, the percentage of ankle fractures surgically treated by podiatrists had increased, whereas that treated by orthopaedic surgeons had decreased. Surgical treatment by podiatrists was associated with higher malunion/nonunion rates among all types of ankle fractures. No differences in complications were observed in patients with unimalleolar fractures. In patients with bimalleolar or trimalleolar fractures, treatment by a podiatrist was associated with higher malunion/nonunion rates. Patients treated by orthopaedic surgeons versus podiatrists had similar comorbidity profiles.DISCUSSION: Surgical treatment of ankle fractures by orthopaedic surgeons was associated with lower rates of malunion/nonunion when compared with that by podiatrists. The reasons for these differences are likely multifactorial but warrants further investigation. Our findings have important implications in patients who must choose a surgeon to surgically manage their ankle fracture, as well as policymakers who determine the scope of practice.LEVEL OF EVIDENCE: Level III-retrospective cohort study.

  View details for DOI 10.5435/JAAOS-D-18-00630

  View details for PubMedID 30601371

• Uncemented Metal-Backed Tantalum Patellar Components in Total Knee Arthroplasty Have a High Fracture Rate at Midterm Follow-Up. journal of arthroplasty Chan, J. Y., Giori, N. J. 2017

  Abstract

  There is interest in uncemented total knee arthroplasty due to the hope for long-term biologic fixation, but limited data are available regarding uncemented tantalum patellar components. The purpose of this study was to evaluate the radiographic outcomes of uncemented tantalum patellar implants at midterm follow-up.We retrospectively reviewed a consecutive series of 30 knees in 29 patients who underwent cementless total knee arthroplasty with an uncemented metal-backed tantalum patella between September 2006 and April 2009. Patients were required to have a minimum radiographic follow-up of 2 years. Anteroposterior and lateral radiographs of the knee were evaluated for signs of implant fracture or gross loosening. Clinical follow-up was obtained by reviewing each patient's most recent orthopedic record.Thirty knees in 29 patients met inclusion criteria. The mean age of the cohort was 59.1 years with a mean body mass index of 31.9 kg/m(2). Mean postoperative radiographic follow-up time was 5.5 years. Six fractures of the patellar component were noted. This represented a fracture rate of 20% among the entire cohort and 35% among the 17 knees with visible patellae on anteroposterior radiograph. All fractures had a transverse pattern. No gross patellar component loosening was noted. Among patients with component fractures, 2 required revisions for instability and 1 revision was for infection.Our results suggest a minimum 20% rate of component fracture at midterm follow-up. Although many of these patellar component fractures were asymptomatic, they have the potential to impact revision rates in the longer term.

  View details for DOI 10.1016/j.arth.2017.02.062

  View details for PubMedID 28341281

• Lateral Column Lengthening for Stage II Posterior Tibial Tendon Dysfunction: Surgical Techniques and an Algorithm for Treatment World Clinics: Orthopedics - Foot and Ankle Surgery Chan, J. Y., Ellis, S. J. Jaypee Brothers Medical Publishers. 2017; 2
• Validation of the Foot and Ankle Outcome Score for Hallux Rigidus. HSS journal : the musculoskeletal journal of Hospital for Special Surgery Hogan, M. V., Mani, S. B., Chan, J. Y., Do, H., Deland, J. T., Ellis, S. J. 2016; 12 (1): 44-50

  Abstract

  There is a clear call for improved patient-centered outcomes. The Foot and Ankle Outcome Score (FAOS) is a region-specific patient-reported measure that has been validated for a number of foot and ankle diagnoses, but not hallux rigidus.The aim of this study was to validate the FAOS in patients with hallux rigidus.From 2007 to 2013, 211 patients with hallux rigidus (HR) were included in the study. For the construct validity portion of the study, 125 patients completed a Short-Form 12 (SF-12) and FAOS survey. Forty additional HR patients were prospectively given questionnaires to assess the relevance of each FAOS question as it pertained to their HR. Reliability was assessed in 36 HR patients via administration of a second FAOS an average 1 month following the first. In 55 patients, preoperative and postoperative FAOS scores were compared to determine responsiveness.All FAOS subscales demonstrated moderate correlation coefficients with the physical functioning, role physical, bodily pain, and physical health component scores of the SF-12, with all subscales demonstrating poor correlation with the SF-12 mental health-related domains. Content validity was high for all FAOS scores, with the exception of the daily activities subscale. All subscales achieved acceptable test-retest reliability with correlation coefficients of ≥0.72. Furthermore, all subscales were rated as responsive to change in postoperative patients (p < 0.001).This study demonstrates the acceptable construct and content validity, reliability, and responsiveness of the FAOS for hallux rigidus. Due to its broad applicability and proven validation across multiple foot and ankle pathologies, the FAOS represents a patient-centered outcome measure that can be reliably used for the assessment of patients with hallux rigidus.

  View details for DOI 10.1007/s11420-015-9466-4

  View details for PubMedID 26855627

• Contribution of Lateral Column Lengthening to Correction of Forefoot Abduction in Stage IIb Adult Acquired Flatfoot Deformity Reconstruction FOOT & ANKLE INTERNATIONAL Chan, J. Y., Greenfield, S. T., Soukup, D. S., Do, H. T., Deland, J. T., Ellis, S. J. 2015; 36 (12): 1400-1411

  Abstract

  Correction of forefoot abduction in stage IIb adult acquired flatfoot likely depends on the amount of lateral column lengthening (LCL) performed, although this represents only one aspect of a successful reconstruction. The purpose of this study was to evaluate the correlation between common reconstructive variables and the observed change in forefoot abduction.Forty-one patients who underwent flatfoot reconstruction involving an Evans-type LCL were assessed retrospectively. Preoperative and postoperative anteroposterior (AP) radiographs of the foot at a minimum of 40 weeks (mean, 2 years) after surgery were reviewed to determine correction in forefoot abduction as measured by talonavicular coverage (TNC) angle, talonavicular uncoverage percent, talus-first metatarsal (T-1MT) angle, and lateral incongruency angle. Fourteen demographic and intraoperative variables were evaluated for association with change in forefoot abduction including age, gender, height, weight, body mass index, as well as the amount of LCL and medializing calcaneal osteotomy performed, LCL graft type, Cotton osteotomy, first tarsometatarsal fusion, flexor digitorum longus transfer, spring ligament repair, gastrocnemius recession and any one of the modified McBride/Akin/Silver procedures.Two variables significantly affected the change in lateral incongruency angle. These were weight (P = .04) and the amount of LCL performed (P < .001). No variables were associated with the change in TNC angle, talonavicular uncoverage percent, or T-1MT angle. Multivariate regression analysis revealed that LCL was the only significant predictor of the change in lateral incongruency angle. The final regression model for LCL showed a good fit (R2 = 0.70, P < .001). Each millimeter of LCL corresponded to a 6.8-degree change in lateral incongruency angle.Correction of forefoot abduction in flatfoot reconstruction was primarily determined by the LCL procedure and could be modeled linearly. We believe that the lateral incongruency angle can serve as a valuable preoperative measurement to help surgeons titrate the proper amount of correction performed intraoperatively.

  View details for DOI 10.1177/1071100715596607

  View details for Web of Science ID 000367841700002

• Optimal Position of the Heel Following Reconstruction of the Stage II Adult-Acquired Flatfoot Deformity FOOT & ANKLE INTERNATIONAL Conti, M. S., Ellis, S. J., Chan, J. Y., Do, H. T., Deland, J. T. 2015; 36 (8): 919-927

  Abstract

  While previous work has demonstrated a linear relationship between the amount of medializing calcaneal osteotomy (MCO) and the change in radiographic hindfoot alignment following reconstruction, an ideal postoperative hindfoot alignment has yet to be reported. The aim of this study was to identify an optimal postoperative hindfoot alignment by correlating radiographic alignment with patient outcomes.Fifty-five feet in 55 patients underwent flatfoot reconstruction for stage II adult-acquired flatfoot deformity (AAFD) by 2 fellowship-trained foot and ankle orthopedic surgeons. Hindfoot alignment was determined as previously described by Saltzman and el-Khoury.(23) Changes in pre- and postoperative scores in each Foot and Ankle Outcome Score (FAOS) subscale were calculated for patients in postoperative hindfoot valgus (≥0 mm valgus, n = 18), mild varus (>0 to 5 mm varus, n = 17), and moderate varus (>5 mm varus, n = 20). Analysis of variance and post hoc Tukey's tests were used to compare the change in FAOS results between these 3 groups.At 22 months or more postoperatively, patients corrected to mild hindfoot varus showed a significantly greater improvement in the FAOS Pain subscale compared with patients in valgus (P = .04) and the Symptoms subscale compared with patients in moderate varus (P = .03). Although mild hindfoot varus did not differ significantly from moderate varus or valgus in the other subscales, mild hindfoot varus did not perform worse than these alignments in any FAOS subscale. No statistically significant correlations between intraoperative MCO slide distances and FAOS subscales were found.Our study indicates that correction of hindfoot alignment to between 0 and 5 mm of varus on the hindfoot alignment view (clinically a straight heel) following stage II flatfoot reconstruction was associated with the greatest improvement in clinical outcomes following hindfoot reconstruction in stage II AAFD.Level III, comparative series.

  View details for DOI 10.1177/1071100715576918

  View details for Web of Science ID 000359152600007

  View details for PubMedID 25948692

  View details for PubMedCentralID PMC4747098

• Crossed-screws provide greater tarsometatarsal fusion stability compared to compression plates. Foot & ankle specialist Baxter, J. R., Mani, S. B., Chan, J. Y., Vulcano, E., Ellis, S. J. 2015; 8 (2): 95-100

  Abstract

  Hallux valgus is a common deformity that is often treated with a fusion of the first tarsometatarsal (TMT) joint. Crossed-screws are currently the accepted standard but advances in plate systems present opportunities for improved clinical outcomes; however, in vitro testing should be performed prior to clinical implementation. The purpose of this study was to determine whether a locking plate with surgeon-mediated compression provides similar fusion stability compared to crossed-screws and if bone density or joint size are related to construct success.Ten matched-pair cadaveric specimens received first TMT fusions with either crossed-screws or a compression plate and were loaded for 1000 cycles to assess the amount of joint motion measured as plantar gapping. Bone density was quantified using computed tomography images of each specimen, and joint height was measured with calipers.Crossed-screws provided 3 times greater resistance to plantar gapping compared to compression plates after 1000 cycles. Bone density and joint size did not affect resistance to plantar gapping for either construct.Lag screws or a plantarly applied plate are needed to maximize TMT fusion stability prior to osseous union. Dorsomedially applied plates are also effective when paired with a lag screw placed across the TMT joint. These constructs do not appear to depend on bone density or joint size, suggesting that patients with osteoporosis are viable candidates.The results of this study suggest that traditional, lagged cross-screws provide greater stability to that of a dorsally place compression plate and may lead to better rates of union.Therapeutic, Level V: Cadaveric Study.

  View details for DOI 10.1177/1938640014543358

  View details for PubMedID 25053793

• New Radiographic Parameter Assessing Hindfoot Alignment in Stage II Adult-Acquired Flatfoot Deformity FOOT & ANKLE INTERNATIONAL Williamson, E. R., Chan, J. Y., Burket, J. C., Deland, J. T., Ellis, S. J. 2015; 36 (4): 417-423

  Abstract

  The hindfoot moment arm is a reliable measurement of hindfoot valgus deformity in stage II adult-acquired flatfoot deformity (AAFD) and can be used to guide intraoperative correction of the hindfoot. There is currently little understanding of how the hindfoot moment arm relates to angular measurements of hindfoot alignment. The purpose of this study was to develop a new hindfoot alignment angle that can reliably quantify hindfoot valgus in patients with AAFD and to establish the relationship of this angle with the hindfoot moment arm.Preoperative hindfoot alignment radiographs were reviewed for 10 consecutive patients (10 feet) who were indicated for reconstruction for stage II AAFD. A second group of 10 patients (10 feet) without flatfoot were identified to serve as normal controls. The hindfoot moment arm and the new hindfoot alignment angle were measured in blinded fashion by 2 readers. Reliability was assessed using intraclass correlation coefficients (ICCs). The difference in angle between normal and flatfoot patients was assessed with a Mann-Whitney U test. A linear regression model was used to assess the relationship between hindfoot moment arm and the new hindfoot alignment angle.Intra- and interrater reliability for the hindfoot alignment angle was excellent (ICC = 0.979 and 0.965, respectively). Flatfoot patients had greater mean angles than did normal patients (22.5 ± 4.9 vs 5.6 ± 5.4 degrees, P < .001). The hindfoot moment arm was correlated significantly with the hindfoot alignment angle (P < .001), increasing by 0.81 mm for every degree increase in angle (adjusted R (2) = 0.9046).These results indicate that the new hindfoot alignment angle is a reliable measure of hindfoot valgus and can differentiate between flatfoot and normal patients. In addition, the strong linear relationship between the hindfoot alignment angle and moment arm may allow for the use of this angle in the intraoperative correction of hindfoot valgus.Level III, retrospective case control study.

  View details for DOI 10.1177/1071100714558846

  View details for Web of Science ID 000352643500010

  View details for PubMedID 25380772

• Correlation of Postoperative Midfoot Position With Outcome Following Reconstruction of the Stage II Adult Acquired Flatfoot Deformity FOOT & ANKLE INTERNATIONAL Conti, M. S., Chan, J. Y., Do, H. T., Ellis, S. J., Deland, J. T. 2015; 36 (3): 239-247

  Abstract

  No studies investigating the effect of the midfoot (talonavicular joint) position on clinical outcomes following flatfoot reconstruction have been performed. The purpose of our study was to determine whether a postoperative abducted or adducted forefoot alignment, as determined from anteroposterior (AP) radiographs, was associated with a difference in outcomes using the Foot and Ankle Outcome Score (FAOS).Midfoot abduction was defined on postoperative AP radiographs, evaluated at a mean of 1.9 years in 55 patients from the authors' institution who underwent flatfoot reconstruction for a stage II adult acquired flatfoot deformity (AAFD), as a lateral incongruency angle greater than 5 degrees, a talonavicular uncoverage angle greater than 8 degrees, and a talo-first metatarsal angle greater than 8 degrees based on previously reported measurements. Patients with 2 or more measurements in the abduction category were classified as the abduction group (n = 30); those with 1 or fewer measurements in the abduction category were placed in the adduction group (n = 25). The preoperative and postoperative FAOS values with a mean follow-up of 3.1 years were compared using Wilcoxon rank-sum tests.Patients corrected to a position of adduction showed significantly lower improvement in the FAOS daily activities (P = .012) and quality of life subscales (P = .046). The mean improvement in subscale scores for the adducted group was lower for pain (P = .052) and sports activities (P = .085) but did not reach statistical significance. No significant difference in the FAOS symptoms subscale (P = .372) between groups was found.Correction of the talonavicular joint to a position of adduction following a stage II AAFD was associated with decreased patient outcomes in daily activities and quality of life compared with an abducted position. These results suggest that overcorrection to a position of midfoot adduction leads to a lesser amount of individual patient improvement in reconstruction of a stage II AAFD.

  View details for DOI 10.1177/1071100714564217

  View details for Web of Science ID 000351246100001

  View details for PubMedID 25589542

  View details for PubMedCentralID PMC4748705

• A case of acute tarsal tunnel syndrome following lateralizing calcaneal osteotomy FOOT AND ANKLE SURGERY Walls, R. J., Chan, J. Y., Ellis, S. J. 2015; 21 (1): E1-E5

  Abstract

  Surgical correction of hindfoot varus is frequently performed with a lateral displacement calcaneal osteotomy. It has rarely been associated with iatrogenic tarsal tunnel syndrome in patients with pre-existing neurological disease. We report the first case of acute postoperative tarsal tunnel syndrome in a neurologically intact patient with post-traumatic hindfoot varus. Early diagnosis and emergent operative release afforded an excellent clinical outcome. Imaging studies can help outrule a compressive hematoma and assess for possible nerve transection; however it is paramount that a high index of suspicion is utilized with judicious operative intervention to minimize long-term sequelae.

  View details for DOI 10.1016/j.fas.2014.07.006

  View details for Web of Science ID 000355012200001

  View details for PubMedID 25682414

• Optimizing stabilization in osteoporotic ankle fractures CURRENT ORTHOPAEDIC PRACTICE Chan, J. Y., Bishop, J. A. 2015; 26 (6): 605-609

  View details for DOI 10.1097/BCO.0000000000000303

• Detection of In Vivo Foot and Ankle Implants by Walkthrough Metal Detectors. Foot & ankle international Chan, J. Y., Mani, S. B., Williams, P. N., O'Malley, M. J., Levine, D. S., Roberts, M. M., Ellis, S. J. 2014; 35 (8): 789-795

  Abstract

  Heightened security concerns have made metal detectors a standard security measure in many locations. While prior studies have investigated the detection rates of various hip and knee implants, none have looked specifically at the detection of foot and ankle implants in an in vivo model. Our goals were to identify which commonly used foot and ankle implants would be detected by walkthrough metal detectors both in vivo and ex vivo.Over a 7-month period, 153 weightbearing patients with foot and ankle hardware were recruited to walk through a standard airport metal detector at 3 different program settings (buildings, airports, and airports enhanced) with a base sensitivity of 165 (arbitrary units), as currently used by the Transportation Security Administration. The number of implants, location and type, as well as the presence of concomitant hardware outside of the foot and ankle were recorded. To determine the detection rate of common foot and ankle implants ex vivo, different hardware sets were walked through the detector at all 3 program settings.Seventeen patients were found to have detectable hardware at the buildings, airports, and airports enhanced settings. An additional 3 patients had hardware only detected at the airports enhanced setting. All 20 of these patients had concomitant metal implants outside of the foot and ankle from other orthopaedic procedures. All patients with foot and ankle implants alone passed through undetected. Seven hardware sets were detected ex vivo at the airports enhanced setting.Our results indicate that patients with foot and ankle implants alone are unlikely to be detected by walkthrough metal detectors at standard airport settings. When additional hardware is present from orthopaedic procedures outside of the foot and ankle, metal detection rates were higher. We believe that these results are important for surgeons in order to educate patients on how they might be affected when walking through a metal detector such as while traveling.Level II, prospective comparative study.

  View details for DOI 10.1177/1071100714534655

  View details for PubMedID 24845551

• Reconstruction of the Stage IIA Adult-acquired Flatfoot Deformity Techniques in Foot & Ankle Surgery Chan, J. Y., Ellis, S. J. 2014; 13 (1): 14-22

  View details for DOI 10.1097/BTF.0000000000000022

• Total Ankle Arthroplasty: An Overview AAOS Monograph Series: Total Ankle Arthroplasty Deland, J. T., Chan, J. Y. American Academy of Orthopaedic Surgeons. 2014; 1: 35–40
• Reconstruction of Achilles Rerupture With Peroneus Longus Tendon Transfer FOOT & ANKLE INTERNATIONAL Chan, J. Y., Elliott, A. J., Ellis, S. J. 2013; 34 (6): 898-903

  View details for DOI 10.1177/1071100712473273

  View details for Web of Science ID 000330309100019

  View details for PubMedID 23696187

• The Contribution of Medializing Calcaneal Osteotomy on Hindfoot Alignment in the Reconstruction of the Stage II Adult Acquired Flatfoot Deformity FOOT & ANKLE INTERNATIONAL Chan, J. Y., Williams, B. R., Nair, P., Young, E., Sofka, C., Deland, J. T., Ellis, S. J. 2013; 34 (2): 159-166

  Abstract

  Successful correction of hindfoot alignment in adult acquired flatfoot deformity (AAFD) is likely influenced by the degree of medializing calcaneal osteotomy (MCO) performed, but it is not known if other reconstruction procedures significantly contribute as well. The purpose of this study was to evaluate the correlation between common preoperative and postoperative variables and hindfoot alignment.Thirty patients with stage II AAFD undergoing flatfoot reconstruction were followed prospectively. Preoperative and postoperative radiographs were reviewed to assess for correction in hindfoot alignment as measured by the change in hindfoot moment arm. Nineteen variables were analyzed, including age, gender, height, weight, body mass index (BMI), medial cuneiform-fifth metatarsal height, anteroposterior (AP) talonavicular coverage, AP talus-first metatarsal, lateral talus-first metatarsal and calcaneal pitch angles as well as intraoperative use of the MCO, lateral column lengthening (LCL), Cotton osteotomy, first tarsometatarsal fusion, flexor digitorum longus transfer, spring ligament reconstruction, and gastrocnemius recession or Achilles lengthening. Mean age was 57.3 years (range, 22-77). Final radiographs were obtained at a mean of 47 weeks (range, 25-78) postoperatively.Seven variables were found to significantly affect hindfoot moment arm. These were gender (P < .05), the amount of MCO performed (P < .001), LCL (P < .01), first tarsometatarsal fusion (P < .01), spring ligament reconstruction (P < .01), medial cuneiform-fifth metatarsal height (P < .001), and calcaneal pitch angle (P < .05). Multivariate regression analysis revealed that MCO was the only significant predictor of hindfoot moment arm. The final regression model for MCO showed a good fit (R(2) = .93, P < .001).Correction of hindfoot valgus alignment obtained in flatfoot reconstruction is primarily determined by the MCO procedure and can be modeled linearly. We believe that the hindfoot alignment view can serve as a valuable preoperative measurement to help surgeons adjust the proper amount of correction intraoperatively.Level IV, prospective case series.

  View details for DOI 10.1177/1071100712460225

  View details for Web of Science ID 000330306300001

  View details for PubMedID 23413053