Degeneration fo the Acetabular Articular Cartilage to Bipolr Hemiathroplasty

초록

Purpose : This study examined the rate of degeneration of the acetabular cartilage by the bipolar head with time, and the clinical factors are associated with the degeneration of the acetabular cartilage Materials and Methods : Among 192 patients (226 hip joint) who underwent bipolar hemiarthroplasty from August 1996 to August 2002, 61 patients (65 hip joint), who were followed up for more than 2 years and showed no signs of dislocation, infection or functional problems, were enrolled in this study. A modified form of a computer assisted vector wear analysis program was used to measure the rate of acetabular cartilage degeneration. The subjects were divided into two groups: those in whom the amount of degeneration of the acetabular cartilage was less than average; and those whose amount of degeneration was more than average. The factors that appeared to affect the rate of acetabular degeneration in the two groups were evaluated. Results :The average linear degenerative change in the acetabular cartilage and the volumetric degenerative change after bipolar hemiarthroplasty was 0.23±0.107 mm/yr and 114±47.2 mm3/yr, respectively. There were significant differences in the activity and HHS between the two groups. The HHS showed an reverse correlation with the linear degeneration and volumetric degeneration, there was a correlation between the activity and the linear and volumetric degeneration. Conclusion : The acetabular cartilage degenerates faster as the patient’ activity increases, and slower with the higher HHS. When surgeons perform hip joint arthroplasty, it is strongly recommended that the life expectancy of the patient and the level of activity be considered when deciding between a hemiarthroplasty or total hip arthroplasty. Key Words :Acetabular cartilage, Degeneration, Bipolar hemiarthroplasty