The medial patellofemoral ligament: a dissection study.

This study examined the anatomy including the innervation of the medial patellofemoral ligament (MPFL) and its relation to neighboring structures to help interpretation of magnetic resonance images and to improve the surgical approach to MPFL repair. The medial aspect of 39 unpreserved human knees were dissected and the MPFL and its relations to neighboring anatomical structures were measured exactly. The morphology and the attachments are described. The MPFL was present in all knees although varying in quality between individuals but not from side to side. The width of the MPFL was 1.9 cm (1.0-3.0) and length 5.3 cm (4.5-6.4). The superior edge of the MPFL medial to the vastus medialis muscle was always easily identified. Failure to identify the superior edge during MPFL surgery is therefore highly suggestive of a MPFL tear. The variation in the ratios of patella height to MPFL length and of patella width to MPFL length ratios was to high too be used to calculate the MPFL length in MPFL reconstruction surgery. The medial patellomeniscal ligament had a wide insertion at the anterior horn of the medial meniscus and a narrow insertion (0.3-0.5 cm) at the inferomedial corner of the patella in layer 3. Histological examination was made of 14 ligaments documenting the presence of free nerve endings but no mechanoreceptors.