Arthroscopic medial meniscus allograft transplantation using a bone-bridge technique improves clinical outcomes with...

To evaluate clinical outcomes, complications, and the surgical technique of arthroscopically assisted medial meniscus allograft transplantation (MMAT) using a medial bone-bridge technique.

A prospective, single-center longitudinal study was performed between 2014 and 2022, including consecutive patients undergoing MMAT with bone-bridge fixation. Outcomes included the International Knee Documentation Committee (IKDC) score, Knee Injury and Osteoarthritis Outcome Score (KOOS), Lysholm score, Tegner activity score, and visual analogue scale (VAS) for satisfaction. All 17 patients were included in the safety analysis. Intraoperative and postoperative complications, graft failure, and MRI findings were assessed. Graft failure was defined as revision meniscal transplantation or conversion to knee arthroplasty. Pre- and postoperative outcomes were compared using paired t-tests or Wilcoxon signed-rank tests (p < 0.05).

Seventeen patients (11 females) underwent MMAT with bone-bridge fixation. Intraoperative bone-bridge fracture occurred in 4 patients (24%) during press-fit seating. In all cases, the fractured components were retained and press-fitted into the trough; rehabilitation was unchanged, and no secondary displacement, reoperation, or postoperative complication attributable to the fracture occurred. Postoperative MRI in all 17 patients demonstrated bone-bridge integration without nonhealing/nonunion or bony impingement. Mean graft extrusion was 3.06 mm (range, 2.1-4.2 mm), and 10 patients (59%) had extrusion >3 mm. No postoperative infections or ACL footprint injuries occurred. One patient developed medial-compartment osteoarthritis with retear of the meniscal allograft 27 months after MMAT and underwent unicompartmental knee arthroplasty; the bone bridge remained intact. No additional graft tears were recorded. This patient was included in the safety analysis but excluded from postoperative outcome analysis. Among the remaining 16 patients, mean follow-up was 50.2 ± 22.0 months (4.2 ± 1.8 years; range, 12-87 months). IKDC, Lysholm, Tegner, all KOOS domains, KOOS total, knee satisfaction, and overall satisfaction improved statistically significantly (all p ≤ 0.011).

Arthroscopically assisted MMAT with medial bone-bridge fixation was associated with improved patient-reported outcomes and few postoperative adverse events. Although intraoperative bone-bridge fracture occurred in 24%, no postoperative complication was attributable to the fracture, and MRI demonstrated bone-bridge integration in all patients. Precise bridge-trough matching is critical to prevent fracture. Larger comparative studies are needed.

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