Association between radiographic joint space narrowing, function, pain and muscle power in severe osteoarthritis of the knee.
OBJECTIVE
To examine the association between radiographic classification of severe knee osteoarthritis and measurements of function, pain and power.


METHODS
Cross-sectional study.


METHODS
Specialist orthopaedic hospital.


METHODS
One hundred and twenty-three patients on the waiting list for elective knee arthroplasty.


METHODS
Weight-bearing antero-posterior radiographs scored for severity of osteoarthritis using the Kellgren and Lawrence scale. Function measured using the function subscale of the WOMAC (Western Ontario and McMaster Universities) index, timed tests of walking speed and sit-to-stand. Pain measured using the pain subscale of the WOMAC index and a visual analogue scale. Extensor strength of the lower limb measured with the leg extensor power rig.


RESULTS
Within any radiographic grade there was considerable variation in function: WOMAC function for patients with grade 2 mean 64 (47-86), grade 3 mean 47 (12-89) grade 4 mean 45 (2-92). There was poor correlation between radiographic score function, pain or muscle power, with no statistically significant associations. A wide range of scores was also seen within patients with the same radiographic grade.


CONCLUSIONS
Radiographic score was not found to be closely associated with function. Amongst patients with the same radiographic score there was considerable variation in function, pain and power.
Barker
Karen
K
Nuffield Orthopaedic Centre NHS Trust, Oxford, UK. Karen.Barker@noc.anglox.nhs.uk
Lamb
Sarah E
SE
Toye
Francine
F
Jackson
Sarah
S
Barrington
Sharon
S
D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D020370:Osteoarthritis, Knee / Q000145:classification / Q000000981:diagnostic imaging* / Q000503:physiopathology; D010146:Pain / Q000145:classification; D010147:Pain Measurement; D011859:Radiography; D012720:Severity of Illness Index; D014850:Waiting Lists