Abstract
Introduction
Despite evidence of long term survival of cemented femoral stem prostheses, studies have shown concerns in the longevity of the cemented sockets. This has led to a rise in the use of uncemented and hybrid implants (with uncemented cup and cemented stem) without long term studies to determine evidence for their use. We aimed to assess whether there is any difference in clinical outcome between cemented and non-cemented acetabular fixation in elderly patients.
Patients and Methods
Between February 2001 and August 2006 186 patients over 72 years of age were prospectively randomised to receive either a cemented Exeter cup or a HA coated press fit cementless cup. Both groups received a cemented Exeter stem. The patients were assessed pre-operatively and reviewed at 6 weeks, 6 months and yearly in a research clinic, by an independent observer. Outcome measures were the Merle D'Aubigné, Postel, Oxford Hip and Visual analogue pain scores. The implants were also assessed radiographically and all complications were recorded.
Results
During the trial 97 patients (mean age 79.13, range 72-90) were randomised to receive a cemented cup (60 right: 37 left) and 89 (mean age 77.65, range 72-95) an uncemented ABG II cup. There was a mean follow-up of 57.6 months (max 9 years) . Statistically there was no significant difference between the two methods of acetabular fixation in outcome measures but radiologically there was a significant difference in wear and loosening (p< 0.001) with cemented cups wearing at a mean of 0.35mm/yr and uncemented cups 0.08mm/yr.
Conclusion
Both methods of fixation were demonstrated to have a good outcome with low complication rates. There would appear to be a significant difference in wear rate and osteolysis in this age group between the methods of fixation up to 9 years.
