Abstract
Introduction:
Total Hip Replacement (THR) is a proven and effective surgical procedure. One of the main limiting factors of the longevity of THR is the performance of the bearing surface. The optimum bearing surface choice, however, remains controversial. We wanted to understand what influenced the choice of bearing surfaces amongst South African orthopaedic surgeons. We also wanted to know if there was any consensus between surgeons and the orthopaedic trade.
Aims, material and methods:
There is no epidemiological registry-based data available in South Africa in respect of bearing surfaces used in hip replacements. We sent out an electronic survey to all members of the South African Orthopaedic Association as well as to trade representatives. Patient parameters influencing the choice of bearing surfaces were surveyed and these included age, gender, level of activity and diagnosis. We used a regressional and tree analysis methodology to interpret the results.
Results:
We received 133 responses from orthopaedic surgeons. There were no differences in decision making and bearing surface choices according to the surgeon's experience, type of practice or fellowship training.
It was statistically significant that age was the first and most important factor when deciding upon a bearing surface. The patient's activity level then played a secondary role in the final choice. We show that gender and clinical diagnosis played no significant part in decision-making.
Ceramic-on-ceramic combinations were used most commonly in younger patients and metal-on-polyethylene in older patients. 73% of surgeons chose metal-on-polyethylene in patients older than 70 years. There were no surgeons who selected metal-on-metal or ceramic-on-metal combinations for any patients.
Metal-on-polyethylene was the first choice in 51% of patients with a low-activity level and 23% of those patients with a high level of activity. Ceramic-on-ceramic and ceramic-on-polyethylene was the first choice in patients with a high level of activity by 32% and 34% of surgeons respectively.
We received 51 responses from the trade representatives surveyed. There was no difference between the surgeons and the trade representatives in respect of their decision making when advising on bearing surfaces to be used in specific patients.
Conclusion:
While each bearing surface combination has advantages and disadvantages we have demonstrated the rationale behind the decision making and the current trends in choices of bearing surfaces by South African orthopaedic surgeons. We note that our surgeon's choices are in line with international trends, especially in respect of metal containing bearing surfaces. We have also shown that the orthopaedic trade representative's guidelines are in keeping with those of the profession.
