Reconstruction of the medial patello-femoral and patello-tibial ligaments for treatment of patellar instability.

PURPOSE: The importance of the medial patello-femoral (MPFL) and medial patello-tibial ligaments (MPTL) to the stability of the patella is undoubted. The purpose of this work was to present a technique for the reconstruction of both ligaments and prospectively record its outcome.
METHODS: Cadaveric part: the MPFL and MPTL were identified in five knee specimens. Sequential cutting and reattaching of these ligaments were performed to study their effect on patellar stability. CLINICAL PART: In the years between 2005 and 2008, twenty-five knees in twenty-one patients had reconstruction of their MPFL and MPTL using the semitendinosus tendon. In eight of these knees, ligament reconstruction was combined with tibial tubercle osteotomy. The IKDC and Insall's classification of outcome were used for the evaluation of all knees.
RESULTS: Cadaveric study revealed that resecting the MPTL increased the lateral translation of the patella up to subluxation at full extension. Intact MPFL avoids full dislocation. Regarding the clinical study, at a minimum 24-months follow-up, all patients reported to have stable patello-femoral joints. There was a significant improvement of the IKDC score 54 ± 2 pre-operatively to 81 ± 2 (Mean ± SD) at 24 months post-operative (P < 0.0003). Nineteen knees scored excellent, five were good and one had fair result.
CONCLUSION: A technique for the reconstruction of the MPFL and MPTL that can be performed through minimally invasive approach has been presented and shown to be successful in restoring knee function in cases of traumatic and recurrent patellar dislocation. LEVEL OF EVIDENCE: III.