Meniscal Repair Outcome in 3829 Patients With a Minimum Follow-up From 2 Years Up to 5 Years: A Meta-analysis on the Overall Failure Rate and Factors Influencing Failure.

BACKGROUND

The importance of meniscal repair is widely accepted because of the association of loss of meniscal tissue with the development of early-onset knee arthritis. Many factors influencing the results of meniscal repair have been reported, but results remain controversial.

PURPOSE: This meta-analysis determines the pooled meniscal repair failure rate of studies with a minimum follow-up of 2 years up to 5 years, with a mean follow-up of 43 months. Moreover, selected failure-influencing factors are analyzed.

STUDY

DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

PubMed and Scopus were searched for studies published between January 2000 and November 2021 reporting on meniscal repair outcome with a minimum follow-up of 24 months. The overall pooled failure rate and pooled failure rates for possible predictors were calculated. Random-effect models were used to pool failure rates, and effect estimates in the form of odds ratios with 95% CIs were established.

RESULTS

The initial literature search identified 6519 studies. A total of 51 studies met the inclusion criteria. In total, 3931 menisci were included with an overall failure rate of 14.8%. Subgroup analysis revealed a significantly lower failure rate for meniscal repair with concomitant anterior cruciate ligament (ACL) reconstruction compared with knees without any reported injury to the ACL (8.5% vs 14%; P = .043). The pooled failure rate for lateral meniscal repair was significantly lower than that for medial meniscal repair (6.1% vs 10.8%; P = .031). Pooled failure rates of all-inside and inside-out repair were not significantly different (11.9% vs 10.6%; P > .05).

CONCLUSION

This meta-analysis on close to 4000 patients demonstrates an overall meniscal repair failure rate of 14.8% at a minimum follow-up from 2 years up to 5 years. Meniscal repair remains a procedure with a high failure rate, especially within the first 2 postoperative years. This review and meta-analysis also identified clinically relevant factors associated with favorable outcomes such as concomitant ACL reconstruction or repair of the lateral meniscus. All-inside meniscal repair with the latest-generation devices yields failure rates of <10%. The failure mechanism and the time of failure is poorly documented; further studies are needed for a better understanding of the retear mechanism.