Growth and Remodelling of the Dysplastic Hip after Conservative Reduction in Congenital Dislocation

Abstract

This study presents the development and remodelling of 78 dysplastic hips treated conservatively. The hip joints were observed from the end of conservative treatment, during growth until maturity, up to the age of 18 years and beyond. We used 9 radiological parameters of hip structure. The parameters described the status of the acetabulum, proximal end of the femur and the joint congruity. The values of these parameters were compared with the norms established for healthy hips. The material was divided into groups with regard to the parameter values. It was found that hip congruity at the age from 2 to 5 years or from 2 to 7 years is the most important factor that determines the development of both the acetabulum and the whole joint. Based on the values of three radiological parameters, describing hip congruity at this period of life, it was found that the remodelling of a dysplastic hip follows one of three definable models. If we attribute the development of a given hip to a given model, then the status of this hip at maturity is predictable. What makes the prediction of the final condition of the hip feasible is the observation of the hip remodelling process from age 2 to 5 or 7 years. This also permits a decision regarding surgery to eliminate any dysplastic elements from the hip during the childs optimal age for operative treatment. (Hip International 2002; 12: 320-33).

Sex Differences in Cartilage Topography and Orientation of the Developing Acetabulum: Implications for Hip Preservation Surgery

“…Prior studies have described the appearance of secondary ossification centers of the ilium and pubis [19] and have recently characterized the irregular ossification pattern of the posterior wall/ ischial secondary ossification center [4]. However, little is known about the development of the articular surface.…”

“…During late childhood and adolescence, secondary ossification centers arise within the hyaline cartilage structure that herald the beginning of acetabular wall ossification. Each ossification center forms within the epiphysis of a respective innominate bone (pubis: os acetabuli, ilium: acetabular epiphysis, ischium: unnamed irregular ossification center of the posterior wall) [4,12,19]. These ossification centers eventually coalesce to form the bony walls of the acetabulum.…”

“…Multiple studies have described the development of the bony acetabulum throughout childhood and adolescence using radiographs and two-dimensional cuts from CT scans [2,5,9,17]. MRI studies have described the development of the acetabular labrum [7], the appearance of secondary ossification centers of the ilium and pubis [19], and have recently characterized the irregular ossification pattern of the posterior wall/ischial secondary ossification center [4]. Little is known about the development of the articular surface.…”