RT Journal A1 Mardones, Rodrigo M. A1 Gonzalez, Carlos A1 Chen, Qingshan A1 Zobitz, Mark A1 Kaufman, Kenton R. A1 Trousdale, Robert T. T1 Surgical Treatment of Femoroacetabular Impingement: Evaluation of the Effect of the Size of the Resection JF The Journal of Bone & Joint Surgery JO The Journal of Bone & Joint Surgery YR 2005 FD February 1 VO 87 IS 2 SP 273 OP 279 DO 10.2106/JBJS.D.01793 UL http://dx.doi.org/10.2106/JBJS.D.01793 AB Background: In patients with symptomatic hip impingement, surgical resection of the femoral head-neck junction may improve the range of motion and relieve pain. A risk of this procedure is fracture. We evaluated the amount of resection of the anterolateral aspect of the femoral head-neck junction that can be done safely.Methods: Cadaveric proximal femoral specimens (fifteen matched pairs) were divided into three groups: 10%, 30%, or 50% of the diameter of one femoral neck was removed, and the contralateral femoral neck was left intact to serve as the control. A compressive load was applied directly to the femoral head. Peak load, stiffness, and energy to fracture were compared among the groups.Results: The energy to fracture differed significantly (p = 0.0015) among the 10%, 30%, and 50% resection groups. The peak load after the 50% resection was significantly less (p = 0.0025) than that after the 10% or 30% resection. With the numbers available, there was no significant difference in peak load between the 10% and 30% resections.Conclusions: Resection of up to 30% of the anterolateral quadrant of the head-neck junction did not significantly alter the load-bearing capacity of the proximal part of the femur. However, a 30% resection significantly decreased the amount of energy required to produce a fracture. Thirty percent should be considered to be the greatest feasible amount of resection because of the change in the pattern of the femoral head-neck response to axial loads that we observed.