Postural sway in single-limb and bilateral quiet standing after unilateral total knee arthroplasty
(English)Manuscript (preprint) (Other academic)
Aim: To investigate the effects of total knee arthroplasty (TKA) on single limb stance and whether reduced stability in single-limb stance may increase postural sway in bilateral quiet standing.
Methods: 3D kinematics for center of mass was used to assess postural sway in 23 subjects with TKA and 23 controls. Tests included bilateral quiet standing with and without vision and on a yielding surface, and single-limb stance.
Results: 30% of the subjects in the TKA group were unable to maintain single-limb stance for 20 s on any leg. Of the 70% in the TKA group able to stand on one leg, mean sway velocity in the medio-lateral direction was higher when standing on the prosthetic leg (p=.02), but no differences were found between the TKA and the control group in single-limb stance. Performance in bilateral quiet standing was similar in TKA-subjects able as well as unable to stand on one leg and controls. Reduced quadriceps strength in the contralateral leg, higher BMI, and older age predicted failure to maintain single-limb stance.
Conclusion: In subjects able to stand on one leg, performance was considered comparable between the prosthetic and contralateral limb and between groups. Inability to stand on one leg did not affect postural sway in bilateral quiet standing. The results suggest that inability to maintain single-limb stance is explained by reduced physical capacity rather than the knee condition in itself. The present study emphasizes the importance of physical activity to improve strength and functional capacity.
IdentifiersURN: urn:nbn:se:umu:diva-91481OAI: oai:DiVA.org:umu-91481DiVA: diva2:736429