Weight-bearing compared with non-weight-bearing following osteochondral autograft transfer for small defects in weight-bearing areas in the femoral articular cartilage of the knee.

Abstract

Patients are routinely kept non-weight-bearing for four to eight weeks following osteochondral autograft transfer to repair cartilage defects of the medial and/or lateral femoral condyle. Therefore, the objective of this novel study was to investigate whether postoperative weight-bearing restrictions affect the outcomes of cartilage repair when an osteochondral autograft transfer system is used to repair small defects in weight-bearing areas of femoral articular cartilage. This a retrospective comparative study. Following review of the charts on 567 consecutive arthroscopic osteochondral autograft transfers, three homogeneous groups of patients with consecutive cases were identified: group A, cases of patients who were non-weight-bearing following the procedure (n = 68); group B, cases of those who were non-weight-bearing following the procedure with concomitant anterior cruciate ligament reconstruction (n = 29); and group C, cases of those who were weight-bearing as tolerated following the procedure (n = 437). The cases of patients whose knees underwent second-look (repeat) arthroscopy were stratified into two subgroups: non-weight-bearing (n = 20) and weight-bearing as tolerated (n = 42). Graft position and manifestation of a repair-adjacent defect (Outerbridge grade-III or IV cartilage defect that develops adjacent to the original osteochondral autograft transfer repair) were assessed during second-look arthroscopy. Cartilage repair was retrospectively assessed from second-look arthroscopy pictures by a blinded, independent orthopaedic surgeon with use of the International Cartilage Repair Society macroscopic cartilage-repair assessment tool. Postoperative complication rates were compared among the three primary groups. The mean grafted area was 0.72 cm(2) (range, 0.16 to 1.45 cm(2)) and 0.73 cm(2) (range, 0.16 to 1.80 cm(2)) for the non-weight-bearing and weight-bearing-as-tolerated second-look subgroups, respectively. The mean International Cartilage Repair Society score was 11.12 and 11.25 points (near-normal cartilage) for the non-weight-bearing and weight-bearing-as-tolerated subgroups (p = 0.71) at a mean follow-up of 42.7 and 33.0 months, respectively. There was no significant difference in the duration of follow-up (p = 0.58), repair-adjacent defect prevalence (p = 0.94), or graft position (p = 0.99) between the two subgroups. Weight-bearing-as-tolerated patients (group C) experienced significantly fewer deep vein thrombosis and arthrofibrosis complications compared with non-weight-bearing patients (groups A and B) (p < 0.001). Postoperative weight-bearing restrictions did not affect mid-term cartilage repair outcomes in patients who underwent second-look arthroscopy when an osteochondral autograft transfer system was used to repair small defects in weight-bearing areas of cartilage of the medial and/or lateral femoral condyle. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.