Clinical and radiologic outcomes after meniscus allograft transplantation at 1-year and 4-year follow-up.

PURPOSE: To assess the clinical and radiologic outcomes of meniscus allograft transplantation (MAT) with serial evaluation at 1 year and at 4 years.

METHODS

Among 151 patients who received MAT between March 2006 and June 2009, we prospectively recruited the patients who had undergone clinical and radiologic examinations at 1 year after the operation. The Lysholm score, International Knee Documentation Committee score, and Knee Society Score were determined. Plain radiography was used for evaluation of osteoarthritis, and magnetic resonance imaging (MRI) was used to assess the cartilage status and meniscal extrusion.

RESULTS

Thirty-nine patients with a mean age of 40 ± 9 years were recruited. The first visit was conducted at a mean of 13.6 months (range, 11 to 17 months) postoperatively, and the last visit was conducted at a mean of 50.4 months (range, 48 to 72 months) postoperatively. Of the patients, 29 were men. The lateral side was involved in 27 patients. The Lysholm knee score increased to a median value of 89 (range, 75 to 100) at the first visit and 88 (range, 76 to 100) at the second visit from a preoperative median value of 79 (range, 37 to 99), which was statistically significant according to the Kruskal-Wallis test. According to the Kellgren-Lawrence grade based on anteroposterior radiographs, 21 patients (54%) showed no arthrosis progression and the overall status of arthrosis on anteroposterior radiographs was significantly changed (P < .001). On MRI, 25 patients (64%) showed no cartilage status change and the overall status was not changed significantly (P = .178). The meniscal extrusion extent was 4.2 ± 0.4 mm at the first visit and 4.2 ± 0.6 mm at the second visit (P = .678), and the relative percentage of extrusion was 0.44 ± 0.16 and 0.51 ± 0.21, respectively (P = .059). The subgroup in which arthrosis had progressed on MRI showed a larger amount of change in the relative percentage of extrusion (P = .023). No correlation was observed between meniscal extrusion and various outcomes.

CONCLUSIONS

Repeat assessment at 4 years showed that MAT showed improvement in knee function, but it had decreased over time. Considerable meniscal extrusion was observed, but it did not increase during follow-up and did not show any correlation with other outcomes. Extrusion progression showed significant correlation with arthrosis progression.

LEVEL OF EVIDENCE: Level IV, therapeutic case series.