Femoral temperatures can exceed the threshold for bone necrosis during resurfacing arthroplasty

A modified surgical technique involving suction and pulsed lavage can help control temperature increases.

Femoral temperatures can significantly increase during cemented hip resurfacing arthroplasty, potentially leading to bone necrosis, a small study found. However, a modified surgical technique involving suction and pulsed lavage can help control temperature increases, the study authors noted.

H.S. Gill, DPhil, and colleagues at the Nuffield Orthopaedic Centre in Oxford, England, investigated the thermal effects of hip resurfacing arthroplasty caused by cement polymerization in nine patients. They published their results in the British edition of the Journal of Bone and Joint Surgery.

The resurfacing arthroplasty group included five patients implanted with a Conserve Plus resurfacing prosthesis [Wright Medical Technology]. Surgeons used a modified surgical procedure, which involved pulsed lavage and a specially designed suction cannula with a 3-mm diameter inserted into the lesser trochanter.

The other four patients were scheduled to undergo a standard total hip replacement (THR). Surgeons performed a "dummy" resurfacing procedure in these patients before excising the femoral head, which only involved manual lavage applied via a finger-pressurized syringe, according to the study.

Researchers found that recorded femoral temperatures in the THR group reached a maximum average of 42.7°C, but ranged from 37°C to 67.9°C. Also, temperatures for the implanted cement began increasing before those for the remaining, non-implanted cement. Maximum recorded temperatures were significantly lower for the actual resurfacing arthroplasty group and averaged 32.7°C, ranging from 31.7°C to 35.6°C (P=.014), according to the study.

"Suction on the lesser trochanter caused the femoral temperature to drop initially from a median of approximately 30°C to that of 20°C [and] to rise again slightly before cementing," the authors reported. "The application of pulsed lavage also reduced the femoral temperature by an additional 4° before cementing."

They added: "The data from our study demonstrate that high bone temperatures [that] could produce necrosis of bone cells can occur during hip resurfacing,. When modification of the surgical technique was performed ... significantly reduced temperatures were recorded, with the maximum temperatures below the threshold required to cause thermal damage," they said.

For more information:
Gill HS, Campbell PA, Murray DW, De Smet KA. Reduction of the potential for thermal damage during hip resurfacing. J Bone Joint Surg Br. 2007;89-B:16-20.