Étude comparative de l'évaluation clinique de l'angle poplité en décubitus dorsal versus décubitus latéral asymétrique, chez des sujets infirmes moteurs cérébraux et polyhandicapés (paralysés cérébraux)

Clinical assessment of lengthening possibilities of hamstring muscles is of great importance for cerebral palsied patients because of progressive and early diminution and its functional and orthopaedic consequences. Traditionally, a clinical assessment is carried out by measuring the popliteal angle with the patient in supine position and hip flexed at 90°. Nevertheless, for patients with CP, able to understand orders, popliteal angle data can change from one clinician to the other because of varying resistance of the muscles at lengthening. On the other hand, more patients relax spontaneously when lying in a lateral and asymmetrical position with the lower limb examined flexed, than in a supine position. In the case where the relaxed state is insufficient, we can use a specific maneuver in order to relax him more. The aim of this article is to report the results of a study made to compare popliteal angle in supine position versus lateral and asymmetrical position. Throughout the maneuvers, the degrees of contraction of the muscles were recorded by a surface electromyography. Variations of the angles were measured with electrical goniometers and verified, on obtaining the final popliteal angle by a mechanical goniometer. Data obtained at the end of the study with a group of 12 patients from 8 to 15 years old, showed that for all patients the angle is higher in the lateral and asymmetrical position than in the supine position, that is to say between 20° to 40° more. These results contest the choice of the decubitus dorsal position to assess the popliteal angle allowed by intrinsic lengthening possibilities (visco-elasticity) of the hamstring muscles and not active resistances due to muscular contraction from diverse pathological factors.