ABSTRACT
BACKGROUND:The uncemented prosthesis in primary total hip arthroplasty has obtained good outcomes, but its application in revision especialy in failed cemented hip arthroplasty deserves further investigations. OBJECTIVE: To observe the mid-term results of uncemented revision of failed cemented hip arthroplasty. METHODS: 41 patients (47 hips) with uncemented revision of failed cemented hip arthroplasty were folowed up from November 1997 to February 2013. In the 47 hips, 24 hips replaced the cemented stem component while 23 hips underwent the cemented acetabular revision. Prosthesis change was observed in radiographs. Harris functions were evaluated and prosthesis survival rate was analyzed. RESULTS AND CONCLUSION: A total of 33 patients (38 hips) were folowed up for 1.3-14.8 years. The mean preoperative Harris hip score increased from 34 (range, 11-66) points to 85 (range, 55-94) points at the time of final folow-up (P < 0.01). 36 hips (95%) had an excelent stability. Osteolysis and migration of the prosthesis were seen in 2 hips (1 in acetabulum and 1 in femur), which needed re-revision. Heterotopic ossification developed in 9 hips (24%). The mean polyethylene liner wear was 0.08 mm (range, 0-0.25 mm) per year. The wear rate only correlated with changes of abduction angle of the acetabulum (P < 0.01). Imaging verified that loosening served as a failure criterion. Kaplan-Meier survival analysis was used to calculate uncemented prosthesis for 7 years and showed that total survival rate was 89%. The survival rates of acetabular prosthesis and femoral prosthesis were respectively 93% and 92%. Results indicated that uncemented prosthesis could deal with the problem of bone deficiency and obtain satisfactory mid-term clinical results in revision of failed cemented hip arthroplasty.
ABSTRACT
BACKGROUND:Total hip arthroplasty is usualy taken to cure patients with ankylosing spondylitis combined with affected hip, to increase their life quality. But, its effects on sagittal balance of the spine-pelvis are not wel known. OBJECTIVE:To analyze the effects of total hip arthroplasty on sagittal balance of the spine-pelvis and life quality in patients with ankylosing spondylitis combined with affected hip. METHODS: Clinic data of 47 consecutive patients with ankylosing spondylitis combined with affected hip who had total hip arthroplasty and were folowed up for more than one year after operation from December 2008 to December 2013 were retrospectively analyzed. The spine-pelvis sagittal balancing parameters were measured. According to the SF-36 questionnaire, the dimensional scores were calculated to assess the life quality. Pearson correlation analysis was performed to analyze the correlation between the balancing parameters and SF-36 scores pre-operation, and the change of the balancing parameters and SF-36 scores pre- and post-operation were analyzed. RESULTS AND CONCLUSION:According to the data before total hip arthroplasty, sagittal vertical axis was negatively correlated with physiological function, body pain and vitality. Total kyphosis was negatively correlated with physiological function and general health. Lumbar lordosis was positively correlated with physiological function. Pelvic tilt angle was negatively correlated with the vitality and social function. Pelvic incident angle was negatively correlated with body pain, vitality and emotional role. No significant correlation was shown between sacral inclination angle and SF-36 items. After total hip arthroplasty, lumbar lordosis and sacral inclination angles were significantly increased, while sagittal vertical axis and pelvic tilt angle were significantly decreased compared with those before surgery. Total kyphosis and pelvic incident angle showed no significant differences before and after surgery. The SF-36 scores al got a statisticaly significant increase. Results showed that, sagittal vertical axis, total kyphosis, lumbar lordosis, pelvic incident angle and pelvic tilt angle are the potential factors influencing the life quality in patients with ankylosing spondylitis combined with affected hip. The total hip arthroplasty, which induces a better sagittal balance with an increased lumbar lordosis and sacral inclination angle, and a decreased sagittal vertical axis and pelvic tilt angle, can result in better life quality.