Lower-limb force production in individuals after unilateral total knee arthroplasty

OBJECTIVE: To determine and compare lower-limb force production during a single-leg horizontal press in involved and uninvolved limbs in people with unilateral total knee arthroplasty (TKA) and the limb of age- and gender-matched subjects. DESIGN: Quasi-experimental, posttest only control group design. SETTING: Subjects living in the community and were tested at a university facility. PARTICIPANTS: Nine people with unilateral TKA and 9 subjects without TKA volunteered. The mean postsurgery time for the TKA group was 15.89+/-6.62 months. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Force production in kilograms during a single-leg press. RESULTS: Lower-limb force production differed significantly between involved and uninvolved limbs (P=.007) for the unilateral TKA group. Lower-limb force production of the involved limb in persons with unilateral TKA was significantly lower than the limb of the age- and gender-matched controls (P=.0001). CONCLUSIONS: Lower-limb force production on the involved side was significantly lower than the uninvolved side. When compared with an age-matched control group, subjects with unilateral TKA produced less force during a single-leg horizontal press.