Keywords
isometric femoral tunnel
patellar luxation
surgical anatomy
How to Cite
Abstract
Introduction: Medial Patellofemoral Ligament (MPFL) reconstruction is the standard of care for recurrent patellar dislocation. However, clinical success is heavily contingent upon precise femoral tunnel placement. Malpositioning can compromise ligament isometry and lead to poor postoperative outcomes. This study evaluates the correlation between anatomical tunnel accuracy and clinical recovery, underscoring the importance of meticulous surgical technique.
Materials and Methods: We retrospectively analyzed 124 patients (124 knees) treated for recurrent patellar dislocation between January 2021 and December 2024. The cohort comprised 31 males and 93 females (mean age 15.4 years). Inclusion criteria included a positive apprehension test, J-sign, and lateral patellar tilt. Postoperative outcomes were assessed using the Lysholm Knee Score. CT and MRI were used to measure the distance from the center of the femoral tunnel to the anatomical isometric point, classifying the positions as isometric or non-isometric.
Results: At a mean follow-up of 18 months, no recurrent dislocations occurred. The mean Lysholm score was 93.8. The average deviation from the isometric point was 4.51 mm; 86 cases (69.4%) were classified as isometric, while 38 (30.6%) were non-isometric. A strong negative correlation was observed between tunnel deviation and Lysholm scores (r = -0.851, P < 0.001). The isometric group demonstrated significantly higher functional scores (95.4 ± 2.2) than the non-isometric group (88.4 ± 3.3; P < 0.001). Furthermore, 58% of the non-isometric group experienced persistent retro-patellar pain, with two patients requiring revision arthroscopy.
Conclusion: Anatomical and isometric restoration of the femoral tunnel is critical for optimal knee function recovery in MPFL reconstruction. Meticulous surgical technique is vital to minimize complications such as residual pain and ensure favorable long-term outcomes.
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