Bifocal Patellar Tendon Avulsion Fracture in a Child

Abstract

The avulsion fracture of the patellar tendon from its proximal and distal attachment is extremely rare. Only a few cases have been described in the English literature and many aspects are still poorly understood. During our practice we came across the case of a 13 year old boy with the above mentioned lesion that we present hereby. Other than describing our experience we tried to tackle the different questions surrounding this lesion, with a careful analysis of the previous reports. A “weaker bone” was considered the main risk factor without any connection with a particular disease or condition. We found out that it is a mainly a pediatric problem, due to the particular bone structure of this population, with many of the subjects being affected by Osgood–Schlatter disease. Different authors have reported their experiences and hypothesis concerning the mechanism behind this injury that has yet to be clearly defined. However most of them mentioned an eccentric load over a knee in forced flexion, leading us to believe that this could be the main source of this unique type of disruption of the extensor apparatus of the knee. Moreover the diagnosis can be quite challenging with many authors advocating for the use of advanced imaging. Treatment options are multiples and the choice relies for the most part on the practitioner preference. From what emerged from the available data it is almost exclusively surgical. Independently from the selected technique, the outcomes are generally favorable.