Vertical Axis Patellar Dislocation With Ipsilateral Femoral Fracture: Use of a Closed Percutaneous Technique for Reduction of the Dislocation

Abstract

Intra-articular vertical axis dislocations are rare injuries, which mostly occur after blunt trauma. In this type of dislocation, the patella rotates along its vertical axis, bringing the articular surface to face medially or laterally. A 13-year-old boy sustained an intra-articular lateral patellar dislocation with a 90 degrees vertical axis medial rotation, which resulted in the articular surface facing laterally, the medial edge of the patella pointing posteriorly, and the lateral edge of the patella pointing anteriorly. As a result, the patella was wedged between the medial and lateral femoral condyles. He also sustained an ipsilateral closed distal femoral shaft fracture. Closed reduction of the dislocation was not successful. Subsequently an A-O reduction clamp was used percutaneously to reduce the patellar dislocation. The femoral fracture was then stabilized by internal fixation using a dynamic compression plate. Isolated vertical and horizontal dislocations have been previously described, but the presence of an ipsilateral femoral shaft fracture makes this a unique case. The percutaneous method used for reduction of the patella has not been previously described. A focused review of the literature, pathoanatomy, and methods of treatment of this condition are presented.