The relationship between femoral cartilage thickness and muscle strength in knee osteoarthritis.
To explore whether femoral cartilage thickness is related (and changes) with muscle strength in subjects with knee osteoarthritis (OA). Forty patients (27 F, 13 M) with knee OA-who were under quadriceps muscle strengthening program-were enrolled in the study. Isokinetic/isometric knee muscle strength measurements (at 30-60° angles and 60-180° velocity) were performed at baseline, end of the muscle strengthening program, and third month control visit using a biodex dynamometer. Femoral cartilage thicknesses (at medial/lateral condyle and intercondylar area) were measured using ultrasonography. Seventy-nine knees of 40 patients (27 F, 13 M) aged 52.03 ± 11.72 years (range, 26-71) were analyzed. Mean VAS scores on the first and third months were significantly lower than the initial values (p < 0.001, p = 0.049). Isometric peak torque and total work values at 180 °/s were significantly higher than the baseline measurements at first and third month controls (all p < 0.05). Cartilage thicknesses (at three sites) were significantly higher than the baseline measurements (all p < 0.05) on the third month but not on the first month (all p > 0.05). Femoral cartilage thicknesses were positively correlated with isometric strength values at baseline and third month. We propose that femoral cartilage thicknesses increase on the third month of strengthening therapy. Since this late-phase thickening parallels the earlier increase in muscle strength (starting, on the first month), we speculate that regeneration rather than edema might be the primary underlying cause.
Department of Physical Medicine and Rehabilitation, Akdeniz University Medical School, Antalya, Turkey. dr.serpiltuna07@hotmail.com.|Akdeniz Üniversitesi Tıp Fakültesi FTR AD, Antalya, Turkey. dr.serpiltuna07@hotmail.com.
Serpil
S
Tuna
Department of Physical Medicine and Rehabilitation, Akdeniz University Medical School, Antalya, Turkey.
Nilüfer
N
Balcı
Department of Physical Medicine and Rehabilitation, Hacettepe University Medical School, Ankara, Turkey.
Levent
L
Özçakar
D000328:Adult; D000368:Aged; D002358:Cartilage, Articular / Q000000981:diagnostic imaging*; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging*; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength; D020370:Osteoarthritis, Knee / Q000503:physiopathology*; D052097:Quadriceps Muscle / Q000503:physiopathology*; D014421:Turkey; D014463:Ultrasonography
Cartilage; Isokinetic; Knee; Osteoarthritis; Ultrasound