High resolution magnetic resonance imaging of the patellar retinaculum: normal anatomy, common injury patterns, and pathologies.

The medial patellar retinaculum (MPR) and the lateral patellar retinaculum (LPR) are vital structures for the stability of the patella. Failure to identify or treat injury to the patellar retinaculum is associated with recurrent patellar instability and contributes to significant morbidity. High-resolution magnetic resonance imaging (MRI) readily depicts the detailed anatomy of various components (layers) of the retinacula. In this review article, we discuss normal anatomy, important landmarks, common injury patterns, and other pathologies encountered in patellar retinacula. High field strength MRI is an excellent noninvasive tool for evaluation of patellar retinaculum anatomy and pathology. This article will help the reader become familiar with normal imaging findings and the most commonly occurring injuries/pathologies in MPR and LPR.