A performance based patient outcome score for active patients following total knee arthroplasty.
OBJECTIVE
The aim of this study was to develop and validate a user friendly performance based knee outcome score for use in active patients undergoing TKA surgery.


METHODS
We prospectively studied a cohort of 50 subjects without any knee symptoms, and 50 patients who underwent TKA for osteoarthritis (OA). The patients were assessed pre- and postoperatively. SF-36 and WOMAC were concurrently administered for comparison. Patients completed seven physical tasks of the finalised outcome instrument which were objectively assessed and scored.


RESULTS
The mean functional score was 31.7 in the normal subjects. The mean functional score improved postoperatively from 10.0 to 17.7 (P < 0.001) in the TKA group. Our results confirm that the performance based score has a high test-retest reliability (intra-class correlation coefficient (ICC) of 0.89), internal consistency (Cronbach's alpha 0.84) and construct validity showing expected correlations with relevant components of the WOMAC and SF-36 scores. The responsiveness as measured by the effect size compared favourably with the same relevant components of the SF-36 and WOMAC.


CONCLUSIONS
Our performance based knee function score is a reliable dimension specific tool to detect change in musculoskeletal function after TKA. It complements existing self-reported outcome tools in facilitating a comprehensive assessment of patients following TKA.
Department of Trauma and Orthopaedics, University College London Hospital, 250 Euston Road, London NW1 2PG, UK. f.hossain@doctors.org.uk
F S
FS
Hossain
S
S
Patel
M A
MA
Fernandez
S
S
Konan
F S
FS
Haddad
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee; D016022:Case-Control Studies; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D020370:Osteoarthritis, Knee / Q000601:surgery*; D011446:Prospective Studies; D020127:Recovery of Function / Q000502:physiology; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires / Q000592:standards*; D016896:Treatment Outcome