Effects of surgical approaches for acetabular fractures with associated gluteal vascular injury.

OBJECTIVES

To examine the viability of the abductor muscles following extensile exposures to the acetabulum in the presence of superior gluteal artery (SGA) or vein (SGV) injury.

DESIGN

In vivo animal study.

INTERVENTION

Twenty-two dogs underwent either an extensile or combined two-incision acetabular approach; either the SGA, the SGV, or no vessel was ligated.

MAIN OUTCOME MEASUREMENTS

Blood flow to the affected gluteal region was evaluated by angiography, laser Doppler flowmetry, and fluorescent microspheres, and histologic and wet weight analyses were performed on the abductor muscles.

RESULTS

Complete ischemic necrosis of the abductor muscles did not occur in any specimen; however, there were statistically significant reductions in immediate postoperative gluteal muscle perfusion (-47 percent, p < 0.01), loss of abductor muscle mass (-41 percent, p < 0.001), and histologic evidence of moderate to severe necrosis in five of seven specimens with extensile exposures and SGA ligation (p = 0.01). Extensile exposure and SGV ligation also caused a significant loss of muscle mass (-25 percent, p < 0.02), with moderate to severe necrosis occurring in four of seven specimens (p < 0.04). Dogs with SGA ligation undergoing the two-incision approach had no significant changes in muscle mass (-3 percent) or perfusion. Moderate to severe necrosis occurred in only one of four specimens.

CONCLUSIONS

This study fails to support the hypothesis that extensile approaches to complex acetabular fractures eliminate abductor collateral circulation when performed in the presence of SGA injury.