Postural control and isometric strength of leg extensor muscle in moderately physically active young and elderly men

Abstract

not described. The aim of this study was to describe standing posture in relation to joint restrictions in children with bilateral CP. Patients/materials and methods: Standing posture in 26 children with CP, mean age 11y (SD 3y), and 19 typically developing children, was recorded for 30 s with 3D motion analysis. Fifteen children with ability to stand without support were designated CP-Group A (GMFCS I-III), and 11 who needed support for standing CP-Group B (GMFCS III-IV). All children were tested with their habitual footwear. Passive joint range of motion (ROM) was measured with a goniometer. Lower limb contractures were defined as passive ROM less than neutral joint position. Results: Unior bilateral joint contractures were equally presented among the children in both CP groups A and B; in the hip (4 vs 7), the knee (6 vs 9), and in the ankle (2 vs 3). CP-Group B presentedwith significantly less passive joint ROM than CPGroup A in hip extension (−4◦(SD 5◦) vs 1◦(SD 5◦), p=0.022), knee extension (−12◦(SD 10◦) vs 0◦(SD 6◦), p≤0.001), and ankle dorsiflexion (2◦(SD 13◦) vs 7◦(SD 7◦), p=0.009) (Fig. 1). Children in bothCP groupsA andB stoodwith significantlymore flexion than their passive jointROMin thehip (p≤0.001vsp=0.004 respectively), in the knee (p=0.003 vs p=0.003), and in the ankle in CP Group A (p=0.012 vs p=0.182) (Fig. 1). Discussion and conclusions: The flexed joint position during standing with respect to the passive joint extension ROM in both CP groups indicates that the children did not utilize their possible joint extensionROMduring upright standing. Kneeflexor spasticity was observed in both groups and might have contributed to difficulties to erect their lower limbs. The large difference between the joint position in the unloaded and the upright positions, in particular in the children who needed support (CPGroup B), might also be interpreted as lower limbmuscle weakness. Which factors contribute to the difficulties to align the body segments and maintain a stable body position with respect to gravity during standing in children with bilateral CP requires further exploration.