Clinical and radiological outcomes of a cartilage-preserving pinhole transtibial technique versus standard pull-out repair for traumatic posterior meniscal root tears.

BACKGROUND

Traumatic posterior meniscal root tears disrupt normal load transmission, resulting in meniscal extrusion and accelerated osteoarthritis. Although transtibial pull-out repair is widely used, creation of a 4.5-mm tibial tunnel at the joint surface may cause iatrogenic chondral and subchondral bone damage at the root footprint. This study aimed to compare the clinical and radiological outcomes of a modified aperture-preserving pinhole technique, designed to avoid reaming at the tibial joint surface, with those of the standard transtibial pull-out repair.

METHODS

A total of 60 patients with symptomatic posterior meniscal root tears treated between December 2021 and December 2024 were retrospectively analyzed. Patients were divided into two groups according to the surgical technique used. The standard pull-out group (n=30) underwent transtibial repair using a 4.5-mm tibial tunnel created by reaming at the joint surface for suture passage. The modified pinhole group (n=30) was treated with an aperture-preserving technique in which fixation was achieved through a narrow pinhole channel without reaming or drilling at the tibial articular surface, thereby preserving the subchondral bone at the root footprint. In both groups, final fixation was performed using a cortical post-fixation screw. Clinical evaluations were performed preoperatively and at 6 and 12 months postoperatively using the Lysholm Knee Score, International Knee Documentation Committee (IKDC) score, Knee Injury and Osteoarthritis Outcome Score (KOOS), and Visual Analog Scale (VAS) for pain. Radiological assessment was conducted using magnetic resonance imaging to evaluate meniscal extrusion and healing status, classified as complete healing, partial (loose) healing, or failed healing.

RESULTS

Both groups demonstrated significant improvement in all functional outcome scores compared with preoperative values (p<0.001). At the 12-month follow-up, the modified pinhole group showed significantly higher Lysholm, IKDC, and KOOS scores than the standard pull-out group, whereas improvements in VAS pain scores were comparable between groups. Meniscal extrusion decreased postoperatively in both groups, with a significantly greater reduction observed in the modified pinhole group. Complete healing was observed in 80% of patients in the modified pinhole group and 60% in the standard pull-out group. No major complications were recorded during the follow-up period.

CONCLUSION

Both surgical techniques resulted in satisfactory clinical and radiological outcomes for posterior meniscal root repair. However, the aperture-preserving modified pinhole technique was associated with superior functional outcomes, reduced progression of meniscal extrusion, and a higher rate of complete healing. Preservation of the subchondral bone and minimization of iatrogenic joint surface damage may positively contribute to meniscal root healing.