Summary

The goal of this study is to determine whether the presence of arthrofibrosis after meniscal repair influences meniscal healing capacity and retear rates, compared to patients who undergo meniscal repair without arthrofibrosis.

Abstract

Introduction

Arthrofibrosis and knee stiffness are well-documented complications following reconstructive knee surgery. While arthrofibrosis is traditionally regarded as a negative outcome, the potential influence of this phenomenon on meniscal healing and retear rates has not previously been assessed. Existing literature reports meniscus re-tear rates ranging averaging between 20-40%, depending on follow-up duration, surgical technique, and suture type. The goal of this study is to determine whether the presence of arthrofibrosis after meniscal repair influences meniscal healing capacity and retear rates, compared to patients who undergo meniscal repair without arthrofibrosis.

Methods

A single-institution retrospective review was conducted on consecutive patients who underwent surgical repair for meniscus tear between January 2011 and August 2024. Patients were included if they subsequently underwent arthroscopic lysis of adhesions (LOA) and/or manipulation under anesthesia (MUA) following initial meniscal repair. Chart review was performed to collect data on meniscus healing state during LOA/MUA, knee range of motion (ROM), occurrence of re-tear, and occurrence of revision surgery. Clinical failure was defined as the need for additional surgical intervention for meniscal retear, such as meniscectomy or revision repair.

Results

Fifty-three patients, with an average age of 29.43 ± 8.84 years (52.8% male, BMI 26.08 ± 4.57), underwent meniscal repair and subsequently developed arthrofibrosis requiring LOA/MUA. LOA and/or MUA procedures occurred an average of 4.26 ± 2.9 months after initial meniscal repair, and the mean follow-up after the index surgery was 47.47 ± 40.5 months. Of the meniscal repairs, 52 (98.1%) had concomitant cruciate ligament reconstruction, and 1 (1.9%) was an isolated meniscal repair. During arthroscopic LOA and/or MUA, 50 patients (94.3%) were found to have a fully intact and healed meniscus. For the remaining 3 patients (5.7%), the healing status was not adequately documented. 2 patients (3.8%) experienced re-tears in the same location as the previous repair. Clinical failure was observed in 1 (1.9%) patient, who went on to undergo revision repair and subsequent revision meniscectomy. The average ROM at the most recent office follow-up was 0.63 ± 2.2° extension to 129.0 ± 5.9° flexion.

Conclusion

This study demonstrates a rather robust healing following meniscal repair in the setting of postoperative arthrofibrosis/stiffness necessitating LOA/MUA with revision and clinical failure rates much lower than that of a standard meniscal repair population. In this cohort, all properly assessed menisci were fully intact and healed during arthroscopic evaluation. The small subset of patients whose healing status was not adequately documented during these procedures have not shown any need for revision surgery at final follow-up. Although the development of stiffness may require additional MUA/LOA procedures to restore proper ROM, it may also reflect an over-active pro-inflammatory response that is possibly beneficial to meniscal healing. These findings highlight the importance of further research into this topic to further delineate the potential effects of arthrofibrosis on meniscal healing, or, more importantly, a pro-inflammatory state on meniscal repair.