title: The ability of massive osteochondral allografts from the medial tibial plateau to reproduce normal joint contact pressures after glenoid resurfacing: the effect of computed tomography matching.
abstract: BACKGROUND
  Current techniques for resurfacing of the glenoid in the treatment of arthritis are unpredictable. Computed tomography (CT) studies have demonstrated that the medial tibial plateau has close similarity to the glenoid. The purpose of this study was to assess contact pressures of transplanted massive tibial osteochondral allografts to resurface the glenoid without and with CT matching.
  
  
  METHODS
  Ten unmatched cadaveric tibiae were used to resurface 10 cadaveric glenoids with osteochondral allografts. Five cadaveric tibiae and glenoids were CT matched and studied. An internal control group of 4 matched pairs of glenoids, with the contralateral glenoid transplanted to the opposite glenoid, was also included as a best-case scenario to measure the effects of the surgical technique. All glenoids were tested before and after grafting at different abduction and rotation angles, with recording of peak contact pressures.
  
  
  RESULTS
  Peak contact pressures were not different from the intact state in the autografted group but were increased in both allografted groups. CT-matched tibial grafts had lower peak pressures than unmatched grafts. Peak pressures were on average 24.8% (range [18.3%, 29.6%]) greater than in the native glenoids for unmatched allografts, 21.8% ([17.0%, 25.5%]) greater for the matched allografts, and 4.9% ([3.8%, 5.5%]) greater for matched autografts.
  
  
  CONCLUSIONS
  Osteochondral grafting from the medial tibial plateau to the glenoid is feasible but results in increased peak contact pressures. The technique is reproducible as defined by the autografted group. Contact pressures between native and allografted glenoids were significantly different. The clinical significance remains unknown. Peak pressures experienced by the glenoid seem highly sensitive to deviations from the native glenoid shape.
authors.affiliation: Steadman Philippon Research Institute, Vail, CO, USA; The Steadman Clinic, Vail, CO, USA.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Millett
authors.affiliation: Steadman Philippon Research Institute, Vail, CO, USA; The Steadman Clinic, Vail, CO, USA; Department of Trauma Surgery and Sports Traumatology, Medical University Innsbruck, Innsbruck, Austria. Electronic address: simon.euler@uki.at.
authors.forename: Simon A
authors.initials: SA
authors.lastname: Euler
authors.affiliation: Steadman Philippon Research Institute, Vail, CO, USA.
authors.forename: Grant J
authors.initials: GJ
authors.lastname: Dornan
authors.affiliation: Steadman Philippon Research Institute, Vail, CO, USA.
authors.forename: Sean D
authors.initials: SD
authors.lastname: Smith
authors.affiliation: Steadman Philippon Research Institute, Vail, CO, USA; The Steadman Clinic, Vail, CO, USA.
authors.forename: Tyler
authors.initials: T
authors.lastname: Collins
authors.affiliation: Steadman Philippon Research Institute, Vail, CO, USA.
authors.forename: Max P
authors.initials: MP
authors.lastname: Michalski
authors.affiliation: Steadman Philippon Research Institute, Vail, CO, USA; The Steadman Clinic, Vail, CO, USA; Department of Trauma and Reconstructive Surgery, University of Leipzig, Leipzig, Germany.
authors.forename: Ulrich J
authors.initials: UJ
authors.lastname: Spiegl
authors.affiliation: Steadman Philippon Research Institute, Vail, CO, USA.
authors.forename: Kyle S
authors.initials: KS
authors.lastname: Jansson
authors.affiliation: Steadman Philippon Research Institute, Vail, CO, USA.
authors.forename: Coen A
authors.initials: CA
authors.lastname: Wijdicks
mesh_terms: D000328:Adult; D000368:Aged; D064591:Allografts; D001178:Arthroplasty; D016025:Bone Transplantation; D002102:Cadaver; D002356:Cartilage / Q000637:transplantation; D004838:Epiphyses / Q000637:transplantation; D005260:Female; D061165:Glenoid Cavity / Q000000981:diagnostic imaging* / Q000601:surgery*; D006801:Humans; D008875:Middle Aged; D010003:Osteoarthritis / Q000601:surgery; D011312:Pressure; D012399:Rotation; D013977:Tibia / Q000000981:diagnostic imaging* / Q000637:transplantation*; D014057:Tomography, X-Ray Computed
keywords: CT matching; Shoulder osteoarthritis; cartilage restoration; medial tibial plateau; osteochondral grafting