OBJECTIVETo investigate the incidence and variation of tunnel enlargement after anterior cruciate ligament (ACL) reconstruction with peroneus longus muscle combined with BMP and allogeneic bone.

METHODSACL reconstructions with peroneus longus muscle combined with BMP and allogeneic bone were performed in 18 patients (18 knees)in the study from March 2007 to July 2009. Among the patients,14 patients were male and 4 patients were female, ranging in age from 21 to 47 years, with an average of 35.5 years. Twelve patients had the injuries in the right knee and 6 patients in the left knee. The CT scans were taken in a consistent manner at the 1st week and the 3rd, 6th, 12th months after surgery to measure tibial and femoral tunnel expansion.

RESULTSTunnel enlargement didn't happen in 18 knees. The average enlargement of 18 cases of femoral tunnel was (1.10 +/- 0.42) mm; and the average enlargement of 18 cases of tibial tunnel was (1.00 +/- 0.51) mm. There was statistical significance of femoral tunnel between the 1st week and the 3rd month after surgery (P < 0.05); and there were no significant difference of the tunnel diameters among the 3rd, 6th, and the 24th months postoperatively (P > 0.05). There was statistical significance of tibial tunnel between the 1st week and the 3rd month after surgery (P < 0.05); there were no significant differences of the tunnel diameters among the 3rd, 6th, and 24th months postoperatively (P > 0.05).

CONCLUSIONAnterior cruciate ligament reconstruction with peroneus longus muscle combined with BMP and allogeneic bone could obviously reduce the incidence of tunnel enlargement. The tunnel diameter obviously increase in 3 months after surgery,and it remains basically unchanged later.