X-ray parameters of sagittal balance in children with multiplanar deformities of the proximal femur

Abstract

BACKGROUND: Multiplanar deformities of the proximal femur in children are often accompanied by a high position of the greater trochanter, causing disturbances in the biomechanics of the hip joint and extra-articular impingement syndrome. Progressive anatomical and biomechanical changes in multiplanar deformities of the proximal femur also lead to changes in the system hip joints, the pelvis, and the lumbosacral spine that mutually burden each other. Currently, the domestic literature has isolated publications on assessing the state of sagittal vertebral-pelvic ratios in children with this pathology.
 AIM: This study assesses the radiological parameters of sagittal balance in children with multiplanar deformities of the proximal femur with a high position of the greater trochanter. It reveals the relationship between the deformity severity of the proximal femur and spinal and pelvic parameter changes in children.
 MATERIALS AND METHODS: The x-ray data of examination of 25 children (25 affected joints) aged from 9 to 15 years with deformities of the proximal femur with a high position of the greater trochanter, in which its apex is located at or above the upper pole of the femoral head, were analyzed. The parameters characterizing the ratio of the femoral head to the greater trochanter in the frontal plane and indicators of the sagittal balance according to lateral skeleton radiographs were evaluated. The obtained data were subjected to statistical processing.
 RESULTS: Children with multiplanar deformities of the proximal femur with a high position of the greater trochanter are characterized by a pronounced increase in global lumbar lordosis, excessive pelvic anteversion, and the pelvic tilt toward the affected limb. A direct relationship was found between the severity of the proximal femur disorders and the degree of change in the sagittal spinal-pelvic ratio indices.
 CONCLUSIONS: The combination and progression of anatomical changes in the hip joints in children with a high position of the greater trochanter cause pathological compensatory changes in the lumbosacral spine with degenerative dystrophic processes development.