Abstract
The aim of this study was to investigate the effects of implant design and gender on the outcome of Total Knee Arthroplasty (TKA) in patients with osteoarthritis (OA).
In this double blind randomised controlled trial, patients with OA received either a standard posterior stabilised implant (n=28) or high flex version of this implant (n=28). Walking speed, knee flexion under anaesthesia (‘drop test’), knee flexion in sitting and during functional activities as measured by electrogoniometry, daily number of steps, Quality of Life (SF36), the function component of the Knee Society Score, pain (Visual Analogue Score) and extensor strength were measured before and one year after TKA.
Type of implant did not have a significant effect on any of the outcome measures recorded, while gender showed significant effects both before and after surgery. Before surgery, females had a significantly lower knee range of motion, (both passive and functional), lower Knee Score function component, walking speed and strength. After surgery they had a statistically significant lower range of knee motion during functional activities such as walking up and down a slope. Strength was also still significantly lower but post-operative self-reported function were similar for both genders. There was also no difference between male and female participants regarding Quality of life, objective daily physical activity or pain.
The results of this study showed that there is a clinically and statistically significant difference between the function of female and male patients both before and after total knee arthroplasty. Although female patients seem to benefit more from TKA than males, on average they do not achieve the same functional knee motion after surgery. Unlike gender, implant design did not influence the knee motion or function in this group of patients. This has important implications for future research and treatment planning in order to maximise the functional outcome after TKA.
Correspondence should be addressed to: BASK c/o BOA, at the Royal College of Surgeons, 35–43 Lincoln’s Inn Fields, London, WC2A 3PE, England.
