Article

The sit-to-stand motion (STS) is a frequently executed activity that is affected
by weakness in the quadriceps femoris muscle and knee joint pain in patients with
knee osteoarthritis (OA). We investigated whether patients with knee OA can
efficiently perform STS through mechanical energy transfer assessments.
Participants were 20 women with knee OA and 17 age-matched asymptomatic controls.
The center of mass (COM), segment angles, joint moments, and powers during STS
were measured. The negative mechanical work in the proximal portion of the shank,
negative mean powers in the distal portion of the pelvis and proximal portion of
the shank, and the positive mean power in the proximal and distal portions of the
thigh were significantly lower in the knee OA group than in the control group.
Patients with knee OA primarily performed thoracic forward lean movement,
shifting their COM closer to the base of support provided by the feet alone, in
an attempt to achieve stability at and after buttocks-off. However, control
ability, which generates and absorbs kinetic energy quickly, was not enhanced in
these patients, and their motion was unable to increase absorption of the
mechanical energy in hip extensors and reduce the load on knee extensors.
Furthermore, STS in patients with knee OA had reduced energy absorption in the
knee extensors from the shank forward lean movement after buttocks-off, had
reduced knee extensor efficiency, and made greater use of physiological energy.
These findings suggest that, from the standpoint of mechanical energy transfer,
patients with knee OA do not perform STS efficiently.
CI - Copyright (c) 2014 Elsevier B.V. All rights reserved.

Langue : ANGLAIS