Minimum 10-year clinical outcomes of combined joint-preserving surgery including autologous chondrocyte cell-sheet transplantation with anterior cruciate ligament reconstruction or high tibial osteotomy for knee osteoarthritis: a case series

Introduction Autologous chondrocyte cell-sheet transplantation is a scaffold-free regenerative strategy that may augment joint-preserving surgery for knee osteoarthritis, but durability beyond early follow-up has remained unclear. Case Series Presentation Between 2011 and 2013, 8 patients with two distinct clinical entities — focal posttraumatic cartilage lesions in anterior cruciate ligament (ACL)-deficient knees, or generalized medial compartment osteoarthritis — underwent autologous chondrocyte cell-sheet transplantation combined with ACL reconstruction or medial open-wedge high tibial osteotomy, respectively. Seven patients (5 men, 2 women; mean age, 48.4 ± 9.2 years) completed minimum 10-year follow-up (mean, 126.7 ± 7.3 months) and were analyzed. Three patients underwent anterior cruciate ligament reconstruction and 4 underwent high tibial osteotomy. Lysholm Knee Score improved from 50.7 ± 16.1 preoperatively to 98.1 ± 2.2 at 3 years and remained higher than baseline at 10 years (82.3 ± 18.4; P=.005), although it declined versus 3 years (P =.043). Knee injury and Osteoarthritis Outcome Score domains improved from baseline; only the Pain subscale declined significantly between 3 and 10 years (P =.038). Kellgren-Lawrence grade remained stable in 5 of 7 knees, progressed in 2, and no analyzed knee underwent total knee arthroplasty. Late deterioration occurred in 2 patients after traumatic graft failure or serious systemic illness. Conclusion In this small, uncontrolled case series, a combined joint-preserving procedure that included autologous chondrocyte cell-sheet transplantation with anterior cruciate ligament reconstruction or open-wedge high tibial osteotomy was associated with maintained clinical improvement and native-knee preservation in most selected patients at minimum 10-year follow-up. Because the independent contribution of the cell sheet cannot be separated from concomitant biomechanical correction, debridement, marrow stimulation, rehabilitation, and patient selection, these findings should be regarded as hypothesis-generating. The observation that late deterioration occurred mainly after intercurrent trauma or serious systemic illness suggests, but does not prove, that long-term outcome may depend on preserved joint-level biomechanics in addition to local cartilage repair.