The patellar ligament: A comprehensive review

The patellar ligament (PL) is an epiphyseal ligament and is part of the extensor complex of the knee. The ligament has gained attention due to its clinical relevance to autograft and tendinopathy. A variety of anatomical variations of the PL such as aplasia, numerical variations, and vascularity are being reported recently by clinicians and anatomists. The aim of this literature was to review the available literature to provide a consensus regarding anatomic variations of the PL, neurovasculature surrounding the PL, histology of the PL, and various aspects of PL measurements with relevance to the surgical considerations and sex and age-related differences. A narrative review of the patellar ligament was performed by conducting a detailed literature search and review of relevant articles. A total of 90 articles on the patellar ligament were included and were categorized into studies based on anatomical variations, neurovasculature, morphometrics, microanatomy, sex and age-related difference, and ACL reconstruction. The anatomical variations and morphometrics of the PL were found to correlate with the frequency of strain injuries, tendinopathy, and efficacy of the PL autograft in anterior cruciate ligament reconstruction. The sex differences in PL measurements and the effect of estrogen on collagen synthesis explained a higher incidence of patellar tendinopathy in women. An awareness of its variations enables careful selection of surgical incisions, thereby avoiding complications related to nerve injury. Accurate knowledge of the PL microanatomy assists in understanding the mechanism of ligament degeneration, rupture, autograft harvesting, and ligamentization results.