[Influence of testing position on lumbar isokinetic measurements].
The studies carried out on the lumbar spine, using an isokinetic type machine, showed the importance of the extensor muscles and the force they develop, compared with the flexor muscles. Both the sitting and standing positions were used without determining the better position. MAIN OBJECTIVE OF THE STUDY: To determine how the patients position influenced the performance of the muscles. We also studied a new parameter : the angle to maximal peak torque (APT).


METHODS
17 healthy subjects and 19 suffering from low back pain were chosen. We perform the test in both positions for each subject. We compare in each group the peak torque of the extensor and flexor muscles on both positions and the angle of this torque.


RESULTS
Low back pain subjects flexor/extensor ratio were 1.71 sitting and 1.56 standing. Healthy subjects showed normal ratio of 0.69 and 0.84.


CONCLUSIONS
The position of the subject has no influence on the results in the low back pain subjects, and the sitting position is preferred. The angle of development of the maximal peak torque in both groups of muscles was very interesting, especially in the subjects suffering from low back pain and shines a new light on the different functions of the muscles of the low back pain suffering subjects and the healthy subjects. This angle (APT) is inversed in low back pain subjects who develop more torque for the extensors in extension of the spine.
Cohen
P
P
Centre médical de Lavey-les-Bains, 1892, Lavey-les-Bains, Suisse, France. paul.cohen@lavey-les-bains.ch
Chantraine
A
A
Gobelet
C
C
Ziltener
J L
JL
D000328:Adult; D001696:Biomechanical Phenomena; D005260:Female; D006801:Humans; D007700:Kinetics; D017116:Low Back Pain / Q000175:diagnosis / Q000209:etiology* / Q000534:rehabilitation; D008159:Lumbar Vertebrae; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000502:physiology; D011187:Posture; D019415:Torque