Treating patella fractures with a fixed-angle patella plate-A prospective observational study.

INTRODUCTION: Anterior tension wiring using Kirschner wires (K-wires) is still considered the standard treatment for patella fractures, despite its high complication rate. The objective of this prospective clinical study was to evaluate intra- and perioperative complications as well as the clinical outcome of patients with patella fracture treated with a new developed bilateral, polyaxial, fixed-angle 2.7mm patella plate.

PATIENTS AND METHODS: Between 2011 and 2014 all patients with a patella fracture were included in this prospective study and treated with a fixed-angle patella plate. Avulsion fractures of the inferior or superior pole of the patella were excluded. All fractures were classified according to the AO/OTA fracture classification. During a twelve-month follow up period all intra- and postoperative complications were recorded as well as the time until fracture healing. One year postoperatively the Lysholm Score, the pre- and postoperative Tegner Score, the Hospital for Special Surgery Knee Score (HSS), the Turba Score, the Oxford Knee Score, the Knee injury and Osteoarthritis Outcome Score (KOOS), the Bostman Score and the Iowa Knee Score were surveyed. Altogether, 20 patella fractures in 19 patients were included in this prospective study. The most frequent type of fracture, n=10, was a simple transverse patella fracture (C1), followed by 7 comminuted patella fractures (C3) and 3 T-shaped patella fractures (C2).

RESULTS: During the 12-month follow up period two patients treated with the patella plate had a complication. In one patient a superficial wound infection occurred, which was treated successfully with hardware removal and in one patient a fracture dislocation due to an implant failure occurred. X-rays demonstrated complete bony healing in all fractures on average 3.2 months postoperatively. All knee scores showed good to excellent clinical results one year postoperatively.

CONCLUSION: The results of this first clinical study indicate that the fixed-angle patella plate is an effective and safe treatment option for patella fractures with a short operative learning curve. The treatment of communited patella fractures (C3) with a fixed-angle patella plate should be well-considered to avoid distending the indication and biomechanical properties.