The biomechanics of the knee of total knee replacement golfers

Abstract

Total knee arthroplasty (TKA) - the replacement of the articulating surfaces of the knee joint - is an increasingly used intervention for osteoarthritis. Younger, more active patients are undergoing TKA due to the clinical success of the implants. Surgeons must make recommendations on the suitability of post-surgery sporting activities; a balance must be struck between the health-promoting nature of the activity and the risk involved to the implant. Golf has been identified as a sport with a large number of participants that is recommended by the majority of knee surgeons. Despite golf being considered a low risk activity, there is limited scientific evidence that the loading applied to the knee joint may be larger than assumed. Thus, the main aim of this thesis was to provide objective biomechanical data to contribute to our scientific knowledge base and to provide meaningful clinical data to enable medical practitioners to make informed decisions regarding the appropriateness of golf as an activity for post-TKA individuals.

Three studies are presented in this thesis. The first investigated the suitability of a standard six-degrees-of-freedom (6DoF) marker model and tested the performance of an alternative model that included an 'optimised', modified cluster design placed on a site of low soft tissue artefact. Whilst statistically significant differences were identified between knee angles derived from each cluster design, the magnitude of the differences were small. Thus, both of the marker models were considered to provide knee-angle measurements that would be considered equivalent in a clinical setting.

Swing timing, the timing of maximum and minimum knee angle and the range of knee rotation in three axes was then presented for four groups of participants: those who had undergone left, right or bilateral TKA and a comparison group of natural knee golfers. A decrease in lead knee flexion between 5° and 10° was observed in participants who had a lead-knee implant, including those participants who had undergone bilateral TKA. All TKA groups exhibited a smaller range of lead knee axial rotation. Bilateral knee flexion between all groups was statistically different but within the active flexion range of the TKA. Measurements of axial rotation in the knees of all groups suggest that previous studies may have underestimated the bilateral range of rotation demanded by the golf swing.

Finally, the temporal characteristics and magnitude of intra knee forces was compared in the four study groups. No statistically significant differences were identified in when maximum and minimum forces occurred within the golf swing. This suggests that the TKA golfers did not adopt protective strategies that accommodate their implants. Peak forces were up to twelve times bodyweight which is higher than previously reported. However, these forces are of extremely short duration and occur infrequently during a game of golf.

Date of Award	Feb 2014
Original language	English
Supervisor	Eric Wallace (Supervisor), MICHAEL HANLON (Supervisor) & DENISE MCGRATH (Supervisor)