Our clinical research

Our team performs leading research in hip preservation and receives competitive grant funding from sources such as the National Institutes of Health (NIH/NIAMS). We specialize in using advanced imaging protocols to assess cartilage health in the hip.

Current on-going investigations include:

• Advanced MR Imaging for assessment of cartilage health of the hip
• Effects of hip arthroscopy on cartilage health of the hip and prevention of arthritis  
• Biomechanical analysis of patients with FAI and early arthritis
• Outcomes of hip arthroscopy and pelvic osteotomy treatments
• Effects of local nerve blocks for pain control after hip procedures
• National database analysis of trends in hip preservation
• Outcomes of hip arthroplasty

Recent publications

• Serna J, Furie K, Wong SE, Swarup I, Zhang AL, Diab M. The Use of Combined Hip Arthroscopy and Periacetabular Osteotomy for Hip Dysplasia Is Increasing and Has Low Complication Rates. Arthrosc Sports Med Rehabil. 2024 Mar 26;6(3):100929. doi: 10.1016/j.asmr.2024.100929.
• Serna J, Nosrat C, Wang KC, Su F, Wong SE, Zhang AL. Socioeconomic Factors Including Patient Income, Education Level, and Health Insurance Influence Postoperative Secondary Surgery and Hospitalization Rates Following Hip Arthroscopy. Arthroscopy. 2024 May 10. doi: 10.1016/j.arthro.2024.04.032.
• Niknam K, Freshman R, Flores SE, Lansdown DA, Wong SE, Zhang AL. Delayed hip arthroscopy for femoroacetabular impingement syndrome does not increase revision but does increase rates of chronic opiate use. J Orthop. 2024 Feb 28;53:49-54. doi: 10.1016/j.jor.2024.02.046.
• Wong SE, Julian KR, Carpio JG, Zhang AL. Proximal Hamstring Repair With All-Suture Anchors and an Accelerated Rehabilitation and Bracing Protocol Demonstrates Good Outcomes at 1-Year Follow-Up. Arthrosc Sports Med Rehabil. 2024 Feb 10;6(2):100891. doi: 10.1016/j.asmr.2024.100891.
• Luitjens J, Gassert FG, Patwardhan V, Bhattacharjee R, Joseph GB, Zhang AL, Souza RB, Majumdar S, Link TM. Is hip capsule morphology associated with hip pain in patients without another structural correlate? Eur Radiol. 2024 Jul;34(7):4321-4330. doi: 10.1007/s00330-023-10307-w.
• Nosrat C, Hartwell MJ, Sadjadi R, Cevallos N, Lansdown DA, Ma CB, Zhang AL. Increasing Hip Arthroscopy Case Volume Is Associated With Increased Risk for Revision Surgery but Not Conversion to Total Hip Arthroplasty or 90-Day Hospitalizations: A Cross-Sectional Analysis of 468 Surgeons. Arthroscopy. 2024 Apr;40(4):1168-1176.e1. doi: 10.1016/j.arthro.2023.08.078.
• Hartwell MJ, Moulton SG, Zhang AL. Capsular Management During Hip Arthroscopy. Curr Rev Musculoskelet Med. 2023 Dec;16(12):607-615. doi: 10.1007/s12178-023-09855-x.
• Soriano KKJ, Hartwell MJ, Nguyen TQ, Flores SE, Zhang AL. Hypermobile Patients With Femoroacetabular Impingement Syndrome Can Be Effectively Treated Utilizing Hip Arthroscopy With Periportal Capsulotomy Closure: A Matched Cohort Analysis Compared to Patients Without Joint Hypermobility. Arthroscopy. 2023 Sep;39(9):2026-2034. doi: 10.1016/j.arthro.2023.03.008.
• Holler JT, Halvorson RT, Salesky M, Ma CB, Feeley BT, Leavitt AD, Lansdown DA, Zhang AL. Incidence of Venous Thromboembolism After Hip Arthroscopy Is Low With or Without Prophylaxis but Risk Factors Include Oral Contraceptive Use, Obesity, and Malignancy. Arthroscopy. 2023 Apr;39(4):981-987.e1. doi: 10.1016/j.arthro.2022.10.029.
• Kannan AS, Hartwell MJ, Grace T, Hammond E, Soriano KKJ, Souza RB, Zhang AL. Correlating Biomechanical Gait Analysis With Patient-Reported Outcomes After Hip Arthroscopy for Femoroacetabular Impingement Syndrome. Orthop J Sports Med. 2022 Sep 5;10(9):23259671221121352. doi: 10.1177/23259671221121352.
• Soriano KKJ, Flores SE, Aung MS, Nguyen TQ, Zhang AL. Treatment of Labral Calcification in the Setting of Femoroacetabular Impingement Syndrome With Arthroscopic Calcification Excision, Labral Repair, and Osteoplasty Improves Outcomes. Arthroscopy. 2021 Feb;37(2):554-563. doi: 10.1016/j.arthro.2020.10.033. 
• Flores SE, Sheridan JR, Borak KR, Zhang AL. When Do Patients Improve After Hip Arthroscopy for Femoroacetabular Impingement? A Prospective Cohort Analysis. Am J Sports Med. 2018 Sep 18:363546518795696. doi: 10.1177/0363546518795696. PMID: 30226992. 
• Hodax JD, Flores SE, Cheung EC, Zhang AL. Use of Air Arthrograms to Aid in Joint Distraction During Hip Arthroscopic Surgery Decreases Postoperative Pain and Opioid Requirements. Orthop J Sports Med. 2019 Apr 10;7(4):2325967119837389. doi: 10.1177/2325967119837389.
• Chambers CC, Monroe EJ, Flores SE, Borak KR, Zhang AL. Periportal Capsulotomy: Technique and Outcomes for a Limited Capsulotomy During Hip Arthroscopy. Arthroscopy. 2019 Mar 11. pii: S0749-8063(18)31028-4. doi: 10.1016/j.arthro.2018.10.142.
• Monroe EJ, Chambers CC, Zhang AL. Periportal Capsulotomy: A Technique for Limited Violation of the Hip Capsule During Arthroscopy for Femoroacetabular Impingement. Arthrosc Tech. 2019 Jan 28;8(2):e205-e208. doi: 10.1016/j.eats.2018.10.015. eCollection 2019 Feb.
• Jansson HL, Bradley KE, Zhang AL. A Systematic Approach to Arthroscopic Femoroplasty With Conservative Management of the Hip Capsule. Arthrosc Tech. 2021 Mar 10;10(3):e797-e806. doi: 10.1016/j.eats.2020.10.071. PMID: 33738217; PMCID: PMC7953266.
• Oji NM, Jansson H, Bradley KE, Feeley BT, Zhang AL. Comparing Patient-Reported Outcome Measurements for Femoroacetabular Impingement Syndrome. Am J Sports Med. 2021 Mar 19:363546521999403. doi: 10.1177/0363546521999403. Epub ahead of print. PMID: 33739894.
• Zhang AL. CORR Insights: A Cam Morphology Develops in the Early Phase of the Final Growth Spurt in Adolescent Ice Hockey Players: Results of a Prospective MRI-based Study. Clin Orthop Relat Res. 2021 Jan 25. doi: 10.1097/CORR.0000000000001648. Epub ahead of print. PMID: 33497064.
• Nguyen TQ, Friedman JM, Flores SE, Zhang AL. Fast Starters and Slow Starters After Hip Arthroscopy for Femoroacetabular Impingement: Correlation of Early Postoperative Pain and 2-Year Outcomes. Am J Sports Med. 2020 Sep 15:363546520952406. doi: 10.1177/0363546520952406. PMID: 32931329.
• Shaw C, Warwick H, Nguyen KH, Link TM, Majumdar S, Souza RB, Vail TP, Zhang AL. Correlation of Hip Capsule Morphology with Patient Symptoms from Femoroacetabular Impingement. J Orthop Res. 2020 Jun 27;. doi: 10.1002/jor.24788.
• Flores SE, Chambers CC, Borak KR, Zhang AL. Is There a Gender Gap in Outcomes After Hip Arthroscopy for Femoroacetabular Impingement? Assessment of Clinically Meaningful Improvements in a Prospective Cohort. Orthop J Sports Med. 2020 Jul 14;8(7):2325967119900561. doi: 10.1177/2325967119900561.
• Chambers CC, Zhang AL. Outcomes for Surgical Treatment of Femoroacetabular Impingement in Adults. Curr Rev Musculoskelet Med. 2019 Jul 10:271-280. doi: 10.1007/s12178-019-09567-1.
• Zhang AL. Editorial Commentary: Arthroscopic Treatment for Diminutive Hip Labral Size: Go Big or Go Home? Arthroscopy. 2021 Jan;37(1):108-110. doi: 10.1016/j.arthro.2020.09.040. PMID: 33384072.
• You JS, Flores SE, Friedman JM, Lansdown DA, Zhang AL. The Learning Curve for Hip Arthroscopic Surgery: A Prospective Evaluation With 2-Year Outcomes in Patients With Femoroacetabular Impingement. Orthop J Sports Med. 2020 Oct 19;8(10):2325967120959140. doi: 10.1177/2325967120959140. PMID: 33178877; PMCID: PMC7592324.
• Zhang AL, Feeley BT. Editorial Commentary: The Rise of Hip Arthroscopy: Temporary Trend or Here to Stay? Arthroscopy. 2018 Jun;34(6):1831-1832. doi: 10.1016/j.arthro.2018.02.023. PMID: 29804605.
• Hartwell MJ, Goldberg DB, Moulton SG, Wong SE, Zhang AL. Single Portal Segmental Labral Reconstruction of the Hip. Arthrosc Tech. 2023;12(5):e771-e778. Published 2023 Apr 24. doi:10.1016/j.eats.2023.02.006
• Garcia-Lopez E, Anigwe C, Wong SE, Zhang AL, Lansdown DA. Age is predictive of higher rate of conversion to total hip arthroplasty after core decompression for osteonecrosis of the hip. J Orthop. 2023;41:79-83. Published 2023 Jun 12. doi:10.1016/j.jor.2023.06.002
• Woolley KA, Chi H, Allahabadi S, Fluet A, Roach C, Ward DT, Wong SE. Sex-Based Differences in the Utilization of Shoulder, Hip, and Knee Arthroplasty. J Am Acad Orthop Surg Glob Res Rev. 2023;7(8):10.5435/JAAOSGlobal-D-23-00022. Published 2023 Aug 7. doi:10.5435/JAAOSGlobal-D-23-00022
• Wong SE, Cogan CJ, Zhang AL. Physical Examination of the Hip: Assessment of Femoroacetabular Impingement, Labral Pathology, and Microinstability. Curr Rev Musculoskelet Med. 2022;15(2):38-52. doi:10.1007/s12178-022-09745-8
• Wong SE, Newhouse AC, Wichman DM, Bessa F, Williams J, Nho SJ. Patients With a High Femoroepiphyseal Roof With Concomitant Borderline Hip Dysplasia and Femoroacetabular Impingement Syndrome Do Not Demonstrate Inferior Outcomes Following Arthroscopic Hip Surgery. Arthroscopy. 2022;38(5):1509-1515. 
• Hartwell MJ, Soriano KKJ, Nguyen TQ, Monroe EJ, Wong SE, Zhang AL. Patient-Reported Outcome Surveys for Femoroacetabular Impingement Syndrome Demonstrate Strong Correlations, High Minimum Clinically Important Difference Agreement and Large Ceiling Effects. Arthroscopy. 2022;38(10):2829-2836. 
• Garcia S, Demetri L, Starcevich A, Gatto A, Swarup I. Developmental Dysplasia of the Hip: Controversies in Management. Curr Rev Musculoskelet Med. 2022;15(4):272-282. doi:10.1007/s12178-022-09761-8
• Cevallos N, Soriano KKJ, Flores SE, Wong SE, Lansdown DA, Zhang AL. Hip Arthroscopy Volume and Reoperations in a Large Cross-Sectional Population: High Rate of Subsequent Revision Hip Arthroscopy in Young Patients and Total Hip Arthroplasty in Older Patients. Arthroscopy. 2021;37(12):3445-3454.e1. doi:10.1016/j.arthro.2021.04.017
• Swarup I, Ricciardi BF, Sink EL. Avoiding Complications in Periacetabular Osteotomy. JBJS Rev. 2015;3(11):e4. doi:10.2106/JBJS.RVW.O.00023
• Tibrewala R, Pedoia V, Lee J, Kinnunen C, Popovic T, Zhang AL, Link TM, Souza RB, Majumdar S. Automatic Hip Abductor Muscle Fat Fraction Estimation and Association with Early OA Cartilage Degeneration Biomarkers. J Orthop Res. 2020 Dec 25. doi: 10.1002/jor.24974. Epub ahead of print. PMID: 33368579.
• Samaan MA, Zhang AL, Popovic T, Pedoia V, Majumdar S, Souza RB. Hip joint muscle forces during gait in patients with femoroacetabular impingement syndrome are associated with patient reported outcomes and cartilage composition. J Biomech. 2018 Dec 23. pii: S0021-9290(18)30924-2. doi: 10.1016/j.jbiomech.2018.12.026. PMID: 30600097
• Neumann J, Zhang AL, Schwaiger BJ, Samaan MA, Souza R, Foreman SC, Joseph GB, Grace T, Majumdar S, Link TM. Validation of scoring hip osteoarthritis with MRI (SHOMRI) scores using hip arthroscopy as a standard of reference. Eur Radiol. 2018 Jul 9. doi: 10.1007/s00330-018-5623-8. PMID: 29987419.
• Flores SE, Chambers C, Borak KR, Zhang AL. Arthroscopic Treatment of Acetabular Retroversion with Acetabuloplasty and Subspine Decompression: A Matched Comparison with Patients Undergoing Arthroscopic Treatment for Focal Pincer-type FAI. Orthop J Sports Med. 2018 Jul 11;6(7):2325967118783741. doi: 10.1177/2325967118783741. PMID: 30046631.
• Grace T, Samaan MA, Souza RB, Link TM, Majumdar S, Zhang AL. Correlation of Patient Symptoms With Labral and Articular Cartilage Damage in Femoroacetabular Impingement. Orthop J Sports Med. 2018 Jun 15;6(6):2325967118778785. doi: 10.1177/2325967118778785. PMID: 29977942.
• Grace T, Neumann J, Samaan MA, Souza RB, Majumdar S, Link TM, Zhang AL. Using the Scoring Hip Osteoarthritis with Magnetic Resonance Imaging (SHOMRI) System to Assess Intra-articular Pathology in Femoroacetabular Impingement. J Orthop Res. 2018 Jun 27. doi: 10.1002/jor.24102. PMID: 29947434.
• Flores SE, Borak KR, Zhang AL. Hip Arthroscopic Surgery for Femoroacetabular Impingement: A Prospective Analysis of the Relationship Between Surgeon Experience and Patient Outcomes. Orthop J Sports Med. 2018 Feb 14;6(2):2325967118755048
• Samaan MA, Pedoia V, Zhang AL, Gallo MC, Link TM, Souza RB, Majumdar S. A Novel MR-based Method for Detection of Cartilage Delamination in Femoroacetabular Impingement Patients. J Orthop Res. 2017 Aug 01
• Tangtiphaiboontana J, Zhang AL, Pandya NK. Outcomes of intra-articular corticosteroid injections for adolescents with hip pain. J of Hip Preservation Surg. 2017 July 4:1–6. doi: 10.1093/jhps/hnx027.
• Samaan MA, Schwaiger BJ, Gallo MC, Sada K, Link TM, Zhang AL, Majumdar S, Souza RB. Joint Loading in the Sagittal Plane During Gait Is Associated With Hip Joint Abnormalities in Patients With Femoroacetabular Impingement. Am J Sports Med. 2017 Mar;45(4):810-818.
• Samaan MA, Schwaiger BJ, Gallo MC, Link TM, Zhang AL, Majumdar S, Souza RB. Abnormal Joint Moment Distributions and Functional Performance During Sit-to-Stand in Femoroacetabular Impingement Patients. PM R. 2016 Oct 8.
• Samaan MA, Zhang AL, Gallo MC, Schwaiger BJ, Link TM, Souza RB, Majumdar S. Quantitative magnetic resonance arthrography in patients with femoroacetabular impingement. J Magn Reson Imaging. 2016 May 18.
• Sing DC, Feeley, BT, Tay B, Vail TP, Zhang AL. Age-related Trends in Hip Arthroscopy: A Large Cross-sectional Analysis. Arthroscopy. 2015 Jul 17.
• Sharifi E., Sharifi H., Morshed S., Bozic K., Diab M.  Cost utility of peri-acetabular osteotomy compared with total hip arthroplasty.  J. Bone Joint Surg. Am. 90:1447-1456, 2008.
• Diab M., Hresko M.T., Millis M.B.  Intertrochanteric corrects geometry better than subcapital osteotomy in SCFE.  Clin. Orthop. 427:204-212, 2004.
• Diab M. and Staheli, L.T.  Practice of Paediatric Orthopaedics.  Lippincott, 2015.
• Theologis A.A., Li X., Souza R., Diab M.  Evaluation of hips with developmental dysplasia using T2 and T1 rho MRI.
• Barry JJ, Masonis JL, Mason JB. Recovery and Outcomes of Direct Anterior Total Hip Arthroplasty. Annals of Joint. 2018. In Press
• Barry JJ, Springer BD. Posterior Approaches to the Hip. Surgery of the Hip 2^nd Edition. In Press
• Barry JJ, Yucekul A, Theologis AA, Hansen EN, Ames C, Deviren V. Spinal realignment for adult deformity: three-column osteotomies alter total hip acetabular component positioning. J Am Acad Orthop Surg. 2017 Feb; 25(2):125-132.
• Barry JJ, Sing DC, Vail TP, Hansen EN. Early Outcomes of Primary Total Hip Arthroplasty After Prior Lumbar Spinal Fusion. J Arthroplasty. 2017 Feb; 32(2):470-474.
• Sing DC, Barry JJ, Aguilar TU, Theologis AA, Patterson JT, Tay B, Vail TP, Hansen EN. Prior lumbar spinal arthrodesis increases risk of prosthetic-related complication in total hip arthroplasty. J Arthoplasty. 2016 Sept; 31(9 Suppl):227-232.