Abstract
Purpose of Study: To develop a non-invasive technique to assess and analyse patella kinematics during the gait cycle.
Methodology and Results: Ten subjects with no history of patellofemoral syndrome or patella maltracking on clinical examination were individually assessed on eight dynamic walking trials each. Retroreflective markers were attached to the proximal, distal, medial and lateral poles of the patella and the position of the patella relative to the centre of the knee joint was tracked and recorded during their gait cycle using a nine camera (120Hz) ViconTM infra-red motion analysis system.
It was found that there was more medial-lateral motion (shift) of the patella than proximal-distal (tilt) motion during the gait cycle.
It was noted that the patella shift motion occurred in the swing phase or the early stance phase of the gait cycle of all subjects with the maximum patella shift occurring when the knee was flexed between 30–56 degrees in the majority of subjects.
Similarly the patellar tilt motion occurred in the swing phase or the early stance phase of the gait cycle with the maximum patella tilt occurring between 20–36 degrees of knee flexion in the majority of subjects.
Conclusion: The results of this study show that patella motion can be identified non-invasively using the ViconTM motion analysis system. These results indicate that normally the maximum amount of patella shift and tilt occurs in the swing and early stance phases of the gait cycle and that abnormal patella motion can be detected if excessive shift or tilt occurs outside of these phases.
Correspondence should be addressed to Mr T Wilton, c/o BOA, BASK at the Royal College of Surgeons, 35–43 Lincoln’s Inn Fields, London WC2A 3PE, England.
