Researchers find an increased rate of early post-THA periprosthetic femur fractures

Surgeon calls the rise in Vancouver Type A1 fractures in the last 3 years a 'mini epidemic.'

ORLANDO, Fla. — Although early periprosthetic femur fractures occurring after total hip arthroplasty are considered rare, research now indicates an increase in rates for some types of these fractures with current total hip arthroplasty practices.

Daniel J. Berry, MD, and colleagues performed a database review of 7,612 primary total hip arthroplasties (THAs) performed during a 10-year period and identified periprosthetic femur fractures that occurred within 3 months after THA performed using uncemented proximally coated stems.

Berry presented the results hereat the 24th Annual Current Concepts in Joint Replacement Winter 2007 Meeting.

The investigators found 28 Vancouver Type A1 fractures that had occurred an average of 27 days postop, 11 of which were not associated with any episode of trauma. Of the 28 patients who sustained an early postoperative fracture, 19 were using arm support to ambulate at the time of the fracture.

In addition, the investigators discovered a 0.14% incidence of these fractures between 1987 and 2003. However, the incidence increased to 0.78% between 2004 and 2007 — a period that is associated with changes in orthopedic practices, such as earlier mobilization, smaller incisions and the use of proximally-coated stems.

"It occurs with increased incidence right now, and I think that it is fair to say that it is becoming a little bit of a mini epidemic," Berry said.

The investigators hypothesized that the breaks could occur from unintegrated stems placed under high loads, or may be unrecognized intraoperative fractures. Berry suggested that surgeons can avoid these fractures by careful patient selection, identifying fractures intraoperatively and recommending prophylactic cerclage for specific patients.

"I think there may be a role for us to take a step back from our enthusiasm to mobilize patients very rapidly and realize that, although we want to mobilize them rapidly, we could also use a little caution in those first few weeks after surgery to try to get the best long-term result without a catastrophic early complication," he said.

For more information:
Berry, DJ. Immediate femoral fracture after primary THA: A mini-epidemic. #15. Presented at the 24th Annual Current Concepts in Joint Replacement Winter 2007 Meeting. Dec. 12-17, 2007. Orlando, Fla.