58770
document
Lengthening the moment arm of the patella confers enhanced extensor mechanism power following total knee arthroplasty . We investigated whether a postulated biomechanical advantage conferred to the extensor mechanism by a change in knee implant design was detectable in patients by direct physical testing . 212 TKA patients were enrolled in a double blind randomized controlled trial to receive either a traditional implant or one which incorporated new design features . Extensor mechanism power output and physical performance on a battery of timed functional activities was assessed pre-operatively and then at 6 , 26 , and 52 weeks post-operatively . Significantly enhanced power output was observed in both groups post-arthroplasty ; however , the new design implant group demonstrated a greater change in power output than the traditional implant group . Posthoc testing of between group differences highlighted greater improvement at all post-operative assessments . At 52 weeks , patients receiving the implant with the postulated biomechanical advantage achieved 116 % of the power output of their contralateral limb , whereas patients with the traditional design achieved 90 % . No between group difference was detected in the patient 's time to complete functional tasks . Thus , patients receiving a knee implant of a modern design ( theoretically able to confer a mechanical advantage to the extensor mechanism ) were found to generate significantly greater extensor power than those receiving a traditional implant without the postulated mechanical advantage .
58771
Intervention_Physical
traditional implant or one which incorporated new design features
58772
Intervention_Physical
new design implant
58773
Intervention_Physical
traditional implant
58774
Intervention_Physical
knee implant of a modern design
58775
Intervention_Physical
traditional implant
58776
Outcome_Physical
extensor mechanism power
58777
Outcome_Physical
Extensor mechanism power output
58778
Outcome_Physical
physical performance on a battery of timed functional activities
58779
Outcome_Physical
power output
58780
Outcome_Physical
power output
58781
Outcome_Physical
Posthoc testing
58782
Outcome_Mental
post-operative assessments
58783
Outcome_Physical
power output of their contralateral limb
58784
Outcome_Physical
extensor power
58785
Participant_Condition
total knee arthroplasty
58786
Participant_Sample-size
212
58787
Participant_Condition
TKA