Evaluation of Radiological Parameters of the Spino-Pelvic Complex in Children with Hip Subluxation in Legg-Calve-Perthes Disease

Abstract

Background. The natural course of Legg-Calve-Perthes disease (LCPD) in children with subtotal or total lesion, which correspond to group III-IV according to the Catterall classification, it often leads to hip subluxation. Any changes in the vertebral-pelvic complex lead to mutual transformation and aggravation of existing deformities. In the Russian literature, there are no data on the assessment of the state of the frontal and sagittal spino-pelvic ratios in children with hip subluxation in LCPD. Purpose to evaluate the radiological parameters of the frontal and sagittal spino-pelvic relations in children with hip subluxation in LCPD. Materials and Methods. The study is based on the results of radiometry of 20 patients (20 hip joints) at an average age of 8.90.6 years with LCPD. Radiometry of the main frontal and sagittal spino-pelvic indices was performed and the type of vertical posture was determined according to P. Rousoully, as well as correlations between the studied parameters. Results. All patients had a pelvic distortion in the frontal plane. The values of PI had insignificant changes in comparison with similar values in the asymptomatic child population, the values of SS and SSA exceeded them, and the values of PT were significantly lower, which indicates the presence of excessive pelvic anteversion. The GLL values significantly exceeded the average statistical indicators. The global sagittal balance indicator (SVA) had negative values. The correlation analysis showed the presence of a strong positive relationship between PI and SS, SS and GLL, SSA and SS, a moderately pronounced positive relationship between PI and PT and a moderately pronounced negative relationship between PO and SS, PO and GLL. Conslusion. In children with LCPD in the fragmentation stage with subtotal or total epiphysis lesion (Catterall group III-IV) and hip subluxation, excessive pelvic anteversion is characteristic, which is expressed in an increase in the angle of inclination of the sacrum (SS) in combination with hyperlordosis of the lumbar spine and negative imbalance, as well as a pelvic distortion towards the affected limb. The totality of these changes corresponds to the IV type of vertical posture according to R. Roussouly, which can contribute to the development of degenerative-dystrophic processes in the lumbar spine.

Keywords

• legg-calve-perthes disease
• fragmentation stage
• hip subluxation
• frontal and sagittal spino-pelvic relations