In the 1990s, a bioactive bone cement (BABC) containing apatite-wollastonite glass-ceramic (AW-GC) powder and bisphenol-a-glycidyl methacrylate resin was developed at our hospital. In 1996, we used BABC to fix the acetabular component in primary total hip arthroplasty (THA) in 20 patients as part of a clinical trial. The purpose of this study was to investigate the long-term results of primary THA using BABC. A total of 20 patients (three men and 17 women) with a mean age of 57.4 years (40 to 71), a mean body weight of 52.3 kg (39 to 64), and a mean body mass index (BMI) of 23.0 kg/m2 (19.8 to 28.6) were evaluated clinically and radiologically. Survival analyses were undertaken, and wear analyses were carried out using a computer-aided method.Aims
Patients and Methods
We undertook a randomised controlled trial to
compare bipolar hemiarthroplasty (HA) with a novel total hip replacement
(THR) comprising a polycarbonate–urethane (PCU) acetabular component
coupled with a large-diameter metal femoral head for the treatment
of displaced fractures of the femoral neck in elderly patients. Functional
outcome, assessed with the Harris hip score (HHS) at three months
and then annually after surgery, was the primary endpoint. Rates
of revision and complication were secondary endpoints. Based on a power analysis, 96 consecutive patients aged >
70
years were randomised to receive either HA (49) or a PCU-THR (47).
The mean follow-up was 30.1 months (23 to 50) and 28.6 months (22
to 52) for the HA and the PCU group, respectively. The HHS showed no statistically significant difference between
the groups at every follow-up. Higher pain was recorded in the PCU
group at one and two years’ follow-up
(p = 0.006 and p = 0.019, respectively). In the HA group no revision
was performed. In the PCU-THR group six patients underwent revision
and one patient is currently awaiting
re-operation. The three-year survival rate of the PCU-THR group
was 0.841 (95% confidence interval 0.680 to 0.926). Based on our findings we do not recommend the use of the PCU
acetabular component as part of the treatment of patients with fractures
of the femoral neck. Cite this article:
We present an update of the clinical and radiological results of 62 consecutive acetabular revisions using impacted morsellised cancellous bone grafts and a cemented acetabular component in 58 patients, at a mean follow-up of 22.2 years (20 to 25). The Kaplan-Meier survivorship for the acetabular component with revision for any reason as the endpoint was 75% at 20 years (95% confidence interval (CI) 62 to 88) when 16 hips were at risk. Excluding two revisions for septic loosening at three and six years, the survivorship at 20 years was 79% (95% CI 67 to 93). With further exclusions of one revision of a well-fixed acetabular component after 12 years during a femoral revision and two after 17 years for wear of the acetabular component, the survivorship for aseptic loosening was 87% at 20 years (95% CI 76 to 97). At the final review 14 of the 16 surviving hips had radiographs available. There was one additional case of radiological loosening and four acetabular reconstructions showed progressive radiolucent lines in one or two zones. Acetabular revision using impacted large morsellised bone chips (0.5 cm to 1 cm in diameter) and a cemented acetabular component remains a reliable technique for reconstruction, even when assessed at more than 20 years after surgery.
