Knee flexor-extensor strength in children.
Isokinetic measurements of knee flexion extension in children and adolescents are a useful means of quantifying strength. In the routine clinical situation with a unilateral problem, evaluation of the affected extremity is usually based on comparisons with the unaffected side. To interpret these results, there must be an appreciation for normal side-to-side differences. Twenty-one normal, healthy children (ages 6-16 years) were evaluated using a Cybex II isokinetic dynamometer at 90 and 240 degrees/sec. In children who were able to generate peak torque values greater than 50 ft-lbs, the side-to-side differences in peak torque averaged 11 +/- 12% (mean +/- SD). A similar amount of variability has been reported with adults. For children with whom peak torque values were less than 50 ft-lbs, the side-to-side differences were much greater (mean = 22 +/- 19%). The stronger leg was equally likely to be on the nondominant side as the dominant side. Side-to-side variability was slightly decreased if the mean of several repetitions was used for comparisons rather than comparing just the single highest peak torque values.
Henderson
R C
RC
University of North Carolina at Chapel Hill 27599-7055.
Howes
C L
CL
Erickson
K L
KL
Heere
L M
LM
DeMasi
R A
RA
D000293:Adolescent; D000367:Age Factors; D001827:Body Height; D001835:Body Weight; D002648:Child; D016552:Ergometry; D005221:Fatigue / Q000503:physiopathology; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007717:Knee / Q000502:physiology*; D008297:Male; D009068:Movement; D009119:Muscle Contraction / Q000502:physiology*; D009132:Muscles / Q000502:physiology*; D012399:Rotation