Biomechanical assessment of forces acting across the patella to determine the optimal treatment of patella fractures [Abstract]

Introduction: In this study the optimal angle of fixation or splintage for partially weight bearing fractures of the patella was determined by a gait analysis measurement system. Subjects and Methods: A knee brace was applied to eight subjects and locked at 0, 10, 20 and 30 degrees. Measurements were also taken for an unlocked brace and in the absence of a brace. The subjects were instructed on partial weight bearing mobilisation. Three dimensional motion analyses were performed using an infrared 8-camera system. The ground reaction force was recorded by two 3-dimensional force plates embedded in the walkway. Kinematic and kinetic data was collected and the data was transferred to a computer programme for further analysis and the forces acting on the patella were calculated. Results: The results showed that the forces acting on the patella were directly proportional to the knee flexion angle. The results also showed that the knee flexion angle does not always correspond with the angle set at the knee brace; however they did exhibit a direct relationship. Conclusion: Our findings show that, for partially weight bearing patella fractures, the optimum form of splintage corresponds with a low knee flexion angle