Meniscal survival rate after anterior cruciate ligament reconstruction.

BACKGROUND: Meniscal suture provides well-documented benefits. Integrity of the cruciate ligaments of the knee is a prerequisite for meniscal healing. Nevertheless, reconstruction of the anterior cruciate ligament (ACL) does not consistently prevent recurrent tearing of a sutured meniscus. We evaluated meniscal survival rates, 5 and 10 years after meniscal suture concomitant with an ACL reconstruction. We compared the outcomes of these repaired menisci to those in which no menisci tears were detected during ACL reconstruction.

METHODS: In this multi-centric retrospective study, we included two groups. One group consists of patients who underwent a meniscal repair. This group was further divided into two subgroups based on whether follow-up was 5 years (n=76) or 10 years (n=39). The control group included 120 patients with normal menisci observed during surgery. We studied meniscal survival rates in each group, and we analyzed risk factors associated with the recurrence of meniscal lesions.

RESULTS: The 5-year meniscal survival rate was significantly higher in the control group than in the meniscal-repair group (95% vs. 80%, respectively; P=0.0029). The controls group also had a higher meniscal survival rate after 10 years, although the difference was not statistically significant (88% vs. 77%, P=0.07). A difference in knee laxity greater than 4mm was associated with a 5-fold increase in the risk of recurrent meniscal tears (P=0.0057). After 5 years, the risk of recurrence was higher for the medial than for the lateral meniscus, whereas after 10 years the difference was no longer statistically significant.

DISCUSSION: Although insufficient healing after meniscal suturing contributes to the risk of further meniscal tears, new lesions can develop in menisci that were undamaged at the time of ACL reconstruction. The risk of a new meniscal lesion is strongly associated with inadequate control of antero-posterior and rotational laxity. Some apparently "new menisci lesions" seems to have been missed during ACL reconstruction.

LEVEL OF EVIDENCE: IV, retrospective study.