Meniscal Transplantation in Symptomatic Patients Under Fifty Years of Age: Survivorship Analysis.

Background: The purpose of this study was to prospectively evaluate the long-term results and survivorship of meniscal transplantation in a consecutive series of patients.

Methods: Forty cryopreserved menisci were implanted into thirty-eight patients. Survival end points were transplant removal, revision, or tibiofemoral compartment pain with daily activities. A worst-case scenario was also calculated for patients who did not have symptoms related to the transplant; in this scenario, additional end points were grade-3 signal intensity, extrusion (>50% of meniscal width), or tear on magnetic resonance imaging; signs of meniscal tear on examination; or radiographic loss of joint space. The Cincinnati Knee and International Knee Documentation Committee rating systems were used.

Results: All patients were followed for a mean postoperative time of eleven years. The estimated probabilities of transplant survival were 88% at five years, 63% at ten years, and 40% at fifteen years. Worst-case survival rate estimates were 73% at five years, 68% at seven years, 48% at ten years, and 15% at fifteen years. The mean time to failure was 8.2 years for medial transplants and 7.6 years for lateral transplants. The functional analysis detected significant improvements for pain, swelling, the patient's perception of the knee condition, walking, stair-climbing, and squatting (p < 0.05).

Conclusions: The survivorship analysis showed that, at ten years, 63% had not required subsequent surgery and were asymptomatic with daily activities. However, this percentage decreased to 40% at fifteen years. Although the data indicated that the majority of cryopreserved meniscal transplants may fail in the long term, the resolution of symptoms and improvement in function for several years justifies the procedure in young patients who are symptomatic after meniscectomy. Patients should be advised that the procedure is not curative in the long term and additional surgery will most likely be required.