To do a total or partial hip replacement for older adults who have a hip fracture has been the question.

Now a large clinical study of almost 1,500 patients in 10 countries world-wide has found those who had a total hip arthroplasty have modestly better function after two years, but a higher incidence of serious complications. The study authors suggest the advantages of total hip replacement may not be compelling.

The study led by McMaster University researchers was published in the New England Journal of Medicine and presented at a conference of the U.S. Orthopedic Trauma Association today.

“Hip fractures rank among the top 10 causes of global disability in adults worldwide,” said Dr. Mohit Bhandari, principal investigator of the study, professor of surgery at McMaster’s Michael G. DeGroote School of Medicine and an orthopedic surgeon.

He added these adults are at substantial risk for death, health complications and reduced quality of life.

In the absence of definitive evidence, he said, guidelines for physicians have previously recommended total hip replacement for femoral neck fracture in people who were able to walk before the fracture.

However, the study showed those who had the hemiarthroplasty could expect equal good results as those with the more extensive total hip arthroplasty.

“This is a big change which will have impact on clinical care,” said Bhandari.

His co-principal investigator, Dr. Thomas Einhorn of New York University, added: “The economic impact of these findings could be substantial and lead to more appropriate use of valuable health care resources.”

The trial was conducted on 1,495 patients 50 or older who had been able to walk before having a displaced femoral neck fracture, at 80 centres in the 10 countries of Canada, the U.S., Spain, United Kingdom, Netherlands, Norway, Finland, Australia, New Zealand and South Africa.

They found the type of surgery had no significant influence on whether there was the need for more hip procedures in the follow 24 months, or on the rate of death. Serious complications happened in 42 per cent of those with the total hip replacement, compared to 37 per cent of those with the partial hip replacement. Those who had the total hip replacement reported better function, less pain and stiffness, than those with the partial hip replacement but the difference was not considered statistically significant.

The authors conclude: “Our results suggest the incidence of secondary procedures after two years is similar for total hip arthroplasty and hemiarthroplasty.

“The limited advantages of total hip arthroplasty, as well as the possible higher risk of complications, may be particularly important in regions of the world where total hip arthroplasty is not easily accessible or is cost-prohibitive.”

The study was funded by the Canadian Institutes of Health Research and the U.S. National Institutes of Health, among others.