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Joseph Zeni, Jr. PT PhD

Dr. Zeni is a professor and researcher in the Department of Rehabilitation and Movement Sciences. His research focuses on improving the quality of life for patients with arthritis of the hip and knee joints. Specifically, Dr. Zeni is investigating ways to restore normal movement patterns after hip and knee replacement. He has a particular interest in developing methods to work with patients outside of the laboratory or clinical setting. He is an investigator on a large clinical trial to retrain symmetrical movement after knee replacement with collaborators at the University of Colorado.  Dr. Zeni is an active member of the American Physical Therapy Association, is an author on numerous peer-review publications, and serves on the Editorial Board of the Arthritis Care and Research Journal. He has served on workgroups to develop clinical practice guidelines for the American Physical Therapy Association, American Academy of Orthopaedic Surgeons, and the American Academy of Hip and Knee Surgeons.

If you are interested in learning more about our research, or getting involved in the laboratory activities, please contact me at

  1. Madara K, Aljehani M, Pozzi F, Colonna E, Zeni J. (2019) The effect of extension assist orthosis with pneumatic bladders on pain and function for patients with early knee osteoarthritis. The Annals of Translational Medicine; in press
  2. Aljehani M, Madara K, Snyder-Mackler L, Christiansen C, Zeni J. (2019) The contralateral knee may not be a valid control for biomechanical outcomes after unilateral total knee arthroplasty. Gait Posture. 2019 May;70:179-184
  3. Zeni J, Flowers P, Bade M, Cheuy V, Stevens-Lapsley J, Snyder-Mackler L. (2018) Stiff knee gait may increase risk of second total knee arthroplasty. J Orthopaedic Research. Feb;37(2):397-402.
  4. Pozzi F, White D, Snyder-Mackler L, Zeni J. (2018) Restoring physical function after total knee arthroplasty: a cross-sectional comparison with implications for rehabilitation. Physiotherapy Theory and Practice. Jun 7:1-12.
  5. Adams D, Pozzi F, Willy R, Carrol A, Zeni J. (2018) Altering cadence or vertical oscillation during running: effects of running related injury factors. International Journal of Sports Physical Therapy. (4):633-642
  6. Youn, I, Youn J, Zeni J, Knarr B. (2018) Biomechanical gait variable estimation using wearable sensors after unilateral total knee arthroplasty. Sensors. May 15;18(5) E1577.
  7. Zeni J, Madara K, Witmer H, Gerhardt R, Rubano J. (2018) The effect of surgical approach on gait mechanics after total hip arthroplasty. Journal of Electromyography and Kinesiology. Feb;38:28-33.
  8. Wellsandt E, Zeni J, Axe M, Snyder-Mackler L.(2017) Hip joint biomechanics in those with and without post-traumatic knee osteoarthritis after anterior cruciate ligament injury. Clinical Biomechanics. Oct 2; 50:63-69
  9. Pozzi F, Madara K, Zeni J. (2017) A six-week supervised exercise and educational intervention after total hip arthroplasty: A case series. International Journal of Sports Physical Therapy. Apr;12(2):259-272
  10. White DK, Li Z, Zhang Y, Marmon AR, Master H, Zeni J, Niu J, Jiang L, Zhang S, Lin J. (2017) Physical function after total knee replacement: An observational study describing outcomes in a small group of women from China and the United States. Archives of Physical Medicine and Rehabilitation. Jul 29. pii: S0003-9993(17)30493-8
  11. Abujaber S, Pozzi F, Zeni J. (2017) Influence of weight bearing visual feedback on movement symmetry during sit to stand task. Clinical Biomechanics. Aug;47:110-116
  12. Cheuy V, Foran J, Paxton R, Bade M, Zeni J, Stevens-Lapsley J. (2017) Arthrofibrosis associated with total knee arthroplasty. J Arthroplasty. Aug;32(8):2604-2611
  13. Pozzi F, Di Stasi S, Zeni J, Barrios JA. (2017) Single-limb drop landing biomechanics in active individuals with and without a history of anterior cruciate ligament reconstruction: A total support analysis. Clinical Biomechanics. Feb 4;43:28-33
  14. Zeni J, Madara K, Rubano J. (2016) The effect of surgical approach on function and strength after total hip arthroplasty. Delaware Medical Journal. 88(11):334-340
  15. Pozzi F, Marmon A, Snyder-Mackler L, Zeni J. (2016) Lower leg compensatory strategies during performance of a step up and over task in patients six-months after total knee arthroplasty. Gait and Posture. Sep;49:41-6.
  16. Dominick G, White D, Zeni J. (2016) The association of psychosocial factors with physical activity and function after total knee replacement: An exploratory study. Archives of Physical Medicine and Rehabilitation. Sep;97(9 Suppl):S218-25
  17. Alnahdi A, Zeni J, Snyder-Mackler. (2016) Quadriceps strength asymmetry predicts loading asymmetry during sit-to-stand task in patients with unilateral total knee arthroplasty. Knee Surg Sports Traumatol Arthrosc. Aug;24(8):2587-94
  18. Adams D, Pozzi F, Carroll A, Rombach A, Zeni J. (2016) Validity and Reliability of a Commercial Fitness Watch for Measuring Running Dynamics. JOSPT Jun;46(6):471-6
  19. Fitzgerald K, Hinman R, Zeni J, Snyder-Mackler L, Bennell K. (2015) Design and conduct of clinical trials for rehabilitation in people with osteoarthritis: recommendations from a task force of the osteoarthritis research society international. Osteoarthritis and Cartilage. May;23(5):803-814
  20. Abujaber S, Rubano J, Marmon A, Pozzi F, Zeni J. (2015) Sit-To-Stand Biomechanics Before and After Total Hip Arthroplasty. The Journal of Arthroplasty. J Arthroplasty. Nov;30(11):2027-33. PMC 4640963
  21. Knarr B, Zeni J, Higginson J. (2015) Change in knee contact force with a simulated change in body weight. Computer Methods in Biomechanics and Biomedical Engineering. 19(3): 320-323 PMC4567548
  22. Pozzi F, Snyder-Mackler L, Zeni J. (2015) Relationship between biomechanical asymmetries during a step up and over task and stair climbing after total knee arthroplasty. Clinical Biomechanics. Jan;30(1):78-85. PMC4298478
  23. Abujaber S, Pozzi F, Marmon A, Gillispie G, Zeni J. (2015) Validity of the Nintendo Wii Balance Board to assess weight bearing asymmetry during sit-to-stand and return-to-sit task. Clinical Biomechanics. Feb;41(2):676-82. PMC4385456
  24. Meira E, Zeni J. (2014) Sports participation following total hip arthroplasty: a review. International Journal of Sports Physical Therapy. 9(6); 839-845. PMC4223292
  25. Zeni J, Pozzi F, Abujaber S, Miller L. (2015) Relationship between physical impairments and movement patterns during gait in patients with end-stage hip osteoarthritis. Journal of Orthopaedic Research. Mar;33(3):382-9. PMC4346450
  26. Logerstedt D, Zeni J, Snyder-Mackler L (2014) Sex differences in patients with different stages of knee osteoarthritis. Archives of Physical Medicine and Rehabilitation. Dec;95(12):2376-81. PMC4254053
  27. Zeni J, Abujaber S, Pozzi F, Raisis L. (2014) Relationship between strength, pain and different measures of functional ability in patients with end-stage hip osteoarthritis. Arthritis Care and Research. Arthritis Care Res. 2014 Oct;66(10):1506-12. PMC4175298
  28. Alnahdi A, Zeni J, Snyder-Mackler L (2014) Hip Abductor Strength Reliability and Association With Physical Function After Unilateral Total Knee Arthroplasty: A Cross-Sectional Study. Physical Therapy. Aug 94(8): 1154-1162. PMC4118074
  29. Marmon A, Pozzi F, Alnahdi A, Zeni J. (2013) The validity of plantarflexor strength measures obtained through hand-held dynamometry measures of force. Int J Sports Phys Ther. Dec;8(6):820-7. PMC3867075
  30. Pozzi F, Snyder-Mackler L, Zeni J. (2013) Physical exercise after total knee arthroplasty: a systematic review of controlled trials. Eur J Phys Rehab Med. Dec;49(6):877-92
  31. Zeni J, Flowers P, Abujaber S, Pozzi F, Snyder-Mackler L. (2013) Biofeedback to promote movement symmetry retraining after knee arthroplasty replacement: A feasibility study. JOSPT Oct;43(10): 715-726 doi:10.2519/jospt.2013.4657 PMC4072454
  32. Vallejo RB, Iglesias ME, Zeni JA, Thomas SJ. (2013) Reliability and Repeatability of the Portable EPS-Platform Digital Pressure Plate System, J Am Podiatr Med Assoc, May-Jun;103(3):197-203.
  33. Marmon A, Zeni J, Snyder-Mackler L. (2013) Perception and Presentation of Function in Patients with Unilateral Versus Bilateral Knee Osteoarthritis. Arthritis Care Res. Mar;65(3):406-13. doi: 10.1002/acr.21825 PMC3537858
  34. McGinnis K, Snyder-Mackler L, Zeni J. (2013) Dynamic joint stiffness and co-contraction in subjects after total knee arthroplasty. Clin Biomech. Feb;28(2):205-10. PMC3604158
  35. Yoshida Y, Zeni J, Alnahdi A, Snyder-Mackler L. (2012) Do patients achieve normal gait patterns 3 years after total knee arthroplasty? JOSPT Dec;42(12):1039-49. PMC4287244 doi: 10.2519/jospt.2012.3763.
  36. Bade M, Stevens-Lapsley J, Zeni J, Snyder-Mackler L. (2012) Predicting Poor Physical Performance after Total Knee Arthroplasty. Journal of Orthopaedic Research. 30(11):1805-10 doi: 10.1002/jor.22140. PMC3417156
  37. Alnadhi A, Zeni J, Snyder-Mackler L. (2012) Muscle Impairments in Patients with Knee Osteoarthritis. Journal of Sports Health: A Multidisciplinary Approach. 4(4): 284-292. DOI: 10.1177/1941738112445726 PMC3435919
  38. Knarr B, Zeni J, Higginson JS. (2012) Comparison of electromyography and joint moment as indicators of co-contraction. Journal of Electromyography and Kinesiology. Aug;22(4):607-11 PMC3506260
  39. McClelland JA, Zeni, JA, Haley R, Snyder-Mackler L. (2012) Functional and Biomechanical Outcomes After Using Biofeedback for Retraining Symmetrical Movement Patterns After Total Knee Arthroplasty: A Case Report. Journal of Orthopaedic and Sports Physical Therapy. 42(2):135-144. doi:10.2519/jospt.2012.3773 PMC3619425
  40. Nazarian DG, Zeni J. (2012) Management of a pelvic mass following a worn uncemented total hip arthroplasty. J Arthroplasty. Feb;27(2):323.
  41. Hartigan EH, Zeni J Jr, Di Stasi S, Axe MJ, Snyder-Mackler L. (2012) Preoperative Predictors for Non-Copers to Pass Return to Sports Criteria After ACL Reconstruction. J Appl Biomech. Aug;28(4):366-73. PMC3596873
  42. Alnahdi A, Zeni J, Snyder-Mackler L. (2011) Gait after unilateral total knee arthroplasty: Frontal plan analysis. Journal of Orthopaedic Research. May;29(5):647-52. doi: 10.1002/jor.21323. PMID: 21184513. PMC3754839
  43. Zeni J and Higginson, JS. (2011) Knee osteoarthritis affects the distribution of joint moments during gait. The Knee. Jun;18(3):156-9. doi:10.1016/j.knee.2010.04.003 PMC2970742
  44. Mizner R, Petterson S, Clements K, Zeni J, Irrgang J, Snyder-Mackler L. (2010) Measuring Functional Improvement after Total Knee Arthroplasty Requires both Performance-Based and Patient-Report Assessments: A Longitudinal Analysis of Outcomes. Journal of Arthroplasty. Aug;26(5):728-37. PMC3008304
  45. Zeni J, Snyder-Mackler, L. (2010) Clinical predictors of elective total joint replacement in persons with end-stage knee osteoarthritis.  BMC Muscloskeletal Disorders. 86(11): doi:10.1186/1471-2474-11-86; PMC287765
  46. Zeni J, Snyder-Mackler, L. (2010) Pre-operative predictors of stair ascent and descent after total knee replacement. Journal of Bone and Joint Surgery. 92: 1130-1136 doi:10.2106/JBJS.I.00299 PMC2859903
  47. Zeni J and Higginson, JS. (2010) Gait parameters and stride-to-stride variability during familiarization to walking on a split-belt treadmill.  Clinical Biomechanics. 25(4): 383-386 doi:10.1016/j.clinbiomech.2009.11.002 PMC2847055
  48. Zeni J, Snyder-Mackler, L. (2010) Most Patients Gain Weight in the Two Years After Total Knee Arthroplasty: Comparison to a Healthy Control Group.  Osteoarthritis and Cartilage. 18(4): 510-514 doi:10.1016/j.joca.2009.12.005; PMC2846226
  49. Zeni J, Rudolph K, Higginson JS. (2010) Alterations in quadriceps and hamstrings coordination in persons with medial compartment knee osteoarthritis. Journal of Electromyography and Kinesiology. Feb;20(1):148-54. PMC2827305
  50. Zeni J, Snyder-Mackler, L. (2010) Early Post-operative function predicts long term outcomes after total knee replacement: The importance of contralateral limb strength.  Physical Therapy Journal. 80(1): 43-54 doi:10.2522/ptj.20090089. (Rose Excellence in Research Award Paper) PMC2802824
  51. Zeni J, Snyder-Mackler, L.  (2009) Clinical outcomes following simultaneous bilateral knee replacement: A two year prospective study. Journal of Arthroplasty.  25 (4), 541-546 doi:10.1016/j.arth.2009.02.016  PMC2876215
  52. Zeni J and Higginson, JS.  (2009) Dynamic knee joint stiffness in persons with a progressive increase in severity of knee osteoarthritis.  Clinical Biomechanics.  24(4): 366-71. doi:10.1016/j.clinbiomech.2009.01.005PMC2696188
  53. Zeni J and Higginson, JS.  (2009) Differences in gait parameters between healthy subjects and persons with moderate and severe knee osteoarthritis: A result of altered walking speed? Clinical Biomechanics 24(4): 372-8. doi:10.1016/j.clinbiomech.2009.02.001 PMC2715920
  54. Zeni J, Richards JG, Higginson JS (2008). Two simple methods for determining gait events during treadmill and overground walking using kinematic data. Gait Posture 27(4): 710-4. PMC2384115

Current Grants: NIH R01 AG056585 (Co-Investigator)

Movement pattern training (MOVE) after total knee arthroplasty randomized clinical trial.

9/15/2017-4/30/2022; National Institutes of Health (NIA)

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