Relationship between electromyographic activity of the vastus lateralis while standing and the extent of bilateral simulated knee-flexion contractures.

摘要: The effect of simulated bilateral knee-flexion contractures (KFC) on the electromyographic (EMG) activity vastus lateralis was studied by testing 10 normal subjects using surface EMG to test hypothesis that knee extensors would increase as a function severity contracture. root mean square determined from four 4-s samples taken at 30-s intervals, during 2 min standing in each five positions KFC (0 degree, degrees, 20 30 degrees and 40 degrees). A randomly balanced order conditions used. were subject means an adjustable line subject's waist sole foot. An analysis variance used contrast activity, significant difference found between (P less than 0.05). (+/- 1 SD) expressed percentage maximum voluntary contraction, 0.3% 0.2) 0 7.6% 5.6) 10.9% 7.6) 16.6% 12.4) 24.0% 14.0) degrees. linear relationship (r2 = 0.986), equation y 0.62 + 0.56 x, where represents x extent 0.0007). results provide insight into increased extensor necessary stand with underline importance treating this common disorder.