Summary

Many previous studies on osteochondral allograft transplantation (OCA) outcomes have included various techniques and different anatomical locations in the same cohort, making it difficult to evaluate the actual outcome of thin-dowel OCA technique for isolated femoral condyle lesions. This is a large long-term follow-up series of OCA dowel technique for isolated femoral condyle cartilage defects, d

Abstract

Background:Cartilage repair for femoral condyle lesions comprise the majority of the biological procedures performed in the knee joint. Treatment options have evolved but there is still uncertanty regarding longer term clinical outcome with current surgical techniques

Purpose

The purpose of this study was to evaluate outcome of OCA transplantation utilizing dowel type grafts for the treatment of isolated femoral condyle cartilage lesions

Methods

This study comprised 187 patients (200 knees) that underwent OCA transplantation for isolated cartilage lesions on the medial or lateral femoral condyle between 1999 and 2014 and had a minimum follow-up of 2 years. Mean patient age was 31.1 ± 11.6 years, 62.6% were male and the medial femoral condyle (MFC) was affected in 69% of the knees. Dowel technique was used in all cases with comercially available surgical instruments utilizing the minimum amount of bone necessary for fixation (modern technique). A single graft was used in 145 knees (72.5%), two grafts were used in 55 knees (27.5%). Average allograft area was 6.3 cm2 (range, 2.3 to 13cm2). Evaluation included International Knee Documentation Committee (IKDC) scores; Knee Injury and Osteoarthritis Outcome Score (KOOS), and patient satisfaction. The frequency and type of further surgery was assessed. OCA failure was defined as a further surgery that involved removal of the allograft. An aditional subgroup analysis on location comparing medial to lateral femoral condyle grafts was performed.
Results:. The average follow-up was 6.7 years (range, 1.9 to 16.5 years). Mean graft thickness was 6.5 ± 1.4 mm (cartilage and bone combined). IKDC scores improved from preoperatively to latest follow-up for pain (5.5 to 2.7), function (3.4 to 7.3) and total scores (43.7 to 75.7) (all p<.001). KOOS pain and activities of daily living scores improved from 66.5 to 85.7 and 74.5 to 91.5, respectively (p<.001) (Table 1). The majority of patients (89%) reported satisfaction with the results of the OCA transplantation. Further surgery was required in 52 knees (26%), of which 16 knees (8% of entire cohort) were defined as OCA failures (4 OCA revisions, 1 arthrosurface, 6 unicompartmental knee arthroplasties, and 5 total knee arthroplasties). The median time to failure was 4.9 years (range, 0.3 to 16.1 years). Survivorship of the OCA was 95.6% at 5 years and 91.2% at 10 years.

Conclusion

OCA transplantation utilizing a modern technique is a valuable procedure in the treatment of distal femur cartilage lesions, with a low graft failure rate, significant improvement in clinical scores, high patient satisfaction, and low reoperation rate. These results are similar or better than any other cartilage repair procedure for isolated femoral condyle lesions