Analysis of X-ray parameters of the acetabulum in patients with cerebral palsy

BACKGROUND: Among the orthopedic consequences of cerebral palsy, instability of the hip joints is one of the most common. Most children with cerebral palsy at birth have close to normal relationships in their hip joints that gradually deteriorates. Progressive instability of the hip joint leads to subluxation and then dislocation of the hip, to a decrease in the range of motion in the joints, to movement disorders and a defect in the ability to sit, as well as an impairment in hygienic care of the child.

AIM: To analyze the X-ray anatomical structure of the acetabulum in unstable hip joint in children with cerebral palsy.

MATERIALS AND METHODS: We examined 42 hip joints in 23 patients with cerebral palsy. Participants were divided into two groups. The main group included the results of the examination of unstable hip joints (31 studies), and the control group included the results of the examination of stable joints (11 studies).

RESULTS: The average index of anteversion of the acetabulum in the main group with a functioning Y-shaped cartilage was 2.5° more than the average value of the norm (p = 0.029), with a nonfunctioning Y-shaped cartilage at 6° less than the normal value (p = 0.017). There was a positive moderate correlation between the anteversion of the acetabulum and the anterior margin angle (r = 0.424, p = 0.017), and a positive moderate correlation between the acetabular index and the anterior margin angle (r = 0.398, p = 0.027).

CONCLUSIONS: The study showed that changes in the acetabulum in patients with pathological dislocation or subluxation of the hip against the background of spastic cerebral palsy were manifested by deformation in the horizontal plane due to retroversion of the acetabulum.