Postoperative stiffness requiring fibroarthrolysis does not impair long-term outcomes after multiligament knee reconstruction.

PURPOSE: To evaluate whether patients requiring surgical reintervention for postoperative stiffness following multiligament knee reconstruction achieve comparable functional outcomes to those who do not require additional surgery. METHODS: A retrospective cohort study was conducted including patients who underwent surgical reconstruction for multiligament knee injuries between January 2015 and February 2023 at a single level-1 trauma centre, with a minimum follow-up of 24 months. Patients who developed postoperative flexion stiffness requiring arthroscopic fibroarthrolysis combined with manipulation under anaesthesia were identified and compared with those who did not require reintervention. The primary outcomes were the Lysholm score and Knee injury and Osteoarthritis Outcome Score (KOOS4) score at final follow-up. RESULTS: A total of 95 patients were included in the final analysis, of whom 16 (16.8%) required surgical reintervention for postoperative stiffness. The mean age was 38.4 ± 13.5 years and the mean follow-up was 73.2 ± 25.1 months. The median time from index surgery to fibroarthrolysis was 5.0 months (interquartile range, 4.0-8.3). At final follow-up, no statistically significant differences were observed between groups in KOOS4 score (57.9 ± 2.8 vs. 62.9 ± 5.4; p = 0.640) or Lysholm score (64.1 ± 2.7 vs. 66.6 ± 6.0; p = 0.831), with minimal effect sizes (r = 0.05 and r = 0.02, respectively). CONCLUSION: Patients who required surgical reintervention for postoperative stiffness after multiligament knee reconstruction achieved functional outcomes comparable to those who did not require additional surgery. Arthroscopic fibroarthrolysis combined with manipulation under anaesthesia appears to be a safe and effective treatment option in this setting, supporting its consideration when conservative management has been exhausted. LEVEL OF EVIDENCE: Level III, retrospective cohort study.