Anterior hook plating of patella fractures: A biomechanical analysis and clinical series.

Abstract

Compare anterior hook plating to established fixation constructs biomechanically and report outcomes and complications in a cohort of patella fractures treated with the technique. Lab based biomechanical study and clinical multicenter retrospective cohort study. Two US level one trauma centers.Patients/Participants: 51 patients (28M, 23F) with 30 simple transverse and 21 comminuted patella fractures. 36 cadaveric patellae for the biomechanical study. Biomechanical- Compared dorsal plating with cerclage wiring and modified tension band cable fixation in a comminuted patella fracture model in 36 cadaveric patellae. Constructs were tested in 0° and 45° of flexion. Clinical - We reviewed a consecutive series of patella fractures in two centers for outcome and complications. Biomechanical - construct stiffness. Clinical - reduction, union, complications, range of motion. Stiffness greatest in dorsal plating in both 0° and 45°. Dorsal plating (976 N, 1643 N) > modified tension band (317, 297) > cerclage (89.8, 150.3). 51 patients with patella fractures fixed with dorsal 2.7 mm mini-fragment plates including a distal to proximal lag screw through the plate from the nose of the patella. 9 Cases were small distal fragments not easily managed with screws and cables. All patients were followed to union. There were 2 infections (1 superficial, 1 deep with nonunion) and 5 had hardware removal (9.8%). Dorsal plating is biomechanically and clinically superior to modified tension band and cerclage techniques in comminuted patella fractures. This method allows for fixation of small distal pole fractures.