Abstract
Many factors have been demonstrated to influence the range of knee movement that an individual can achieve.
The purpose of this study was to objectively demonstrate how range of knee movement is affected when the influence of pain is abolished.
Sixty-eight patients with degenerative joint disease presenting for primary total knee arthroplasty were recruited. Using a digital camera, images were taken before and after the induction of anaesthesia with the lower limb in four positions- extension, forced extension, flexion and forced flexion. Camera set up was standard and the range of knee motion was measured from the digital images.
Average arc of motion before anaesthesia was 96° (range, 41°–157°). After induction of anaesthesia, the arc of motion increased to 115° (range, 410–161°). Knee extension improved by an average of 5° (range, 0–15°) and flexion improved by an average of 16° (range, 0–65°).
In conclusion, these results demonstrate that pain has a significant inhibitory effect on the measured range of knee movement before surgical intervention.
The abstracts were prepared by Mr R. B. Smith. Correspondence should be addressed to him at the British Orthopaedic Association, Royal College of Surgeons, 35-43 Lincoln’s Inn Fields, London WC2A 3PN.
