Arthroscopic Femoral Osteochondroplasty for Cam-type Femoroacetabular Impingement: Cortical–Cancellous Sclerotic Boundary Guides Resection Depth

Abstract

Hip arthroscopy and femoral osteochondroplasty are commonly used in the treatment of femoroacetabular impingement (FAI). Determining the correct resection depth of the femoral headeneck cam lesion intraoperatively can be challenging. Both inadequate resection and over-resection may result in complications, underlying the importance of using a consistent and accurate technique when resecting and reshaping the proximal femur. Osseous resection to a depth of the subchondral corticalecancellous bone margin in individuals with FAI has been shown to restore proximal femoral anatomy to within submillimeter differences when compared with control subjects without FAI. This bony boundary may be used as an intraoperative guide to consistently achieve appropriate resection depth. The sclerotic margin indicating the extent of the cam-type deformity can be evaluated with preoperative radiographs and recreated fluoroscopically, giving the surgeon a reliable intraoperative template. In addition, changes in clinical appearance during arthroscopy, particularly identification of the underlying trabecular structure at the corticalecancellous border during resection, provides a visible, reliable intraoperative guide to resection depth.

Editorial Commentary: Not Yet Convinced That the Femoroacetabular Impingement Resection (Fair) Arc Measurement Provides a “Fair” Assessment of Cam Resection Principles

“…We have previously published articles on this concept as well. 4,5 Overall, I believe this study provides an interesting radiographic guide to help assess adequate resection of cam lesions in FAI patients. Although I am not ready to endorse the FAIR arc as a useful measurement for cam resection, I will certainly keep an open mind and continue to test the measurement on my patients so I may understand its utility.…”

Arthroscopic Treatment of Cam-Type Impingement for Femoroacetabular Impingement Using Patient’s Own 1:1 Three-Dimensional Printed Hip Model Without the Use of Fluoroscopy

“…Many have created novel protocols/measurements with the use of intraoperative C-arm imaging, which may not be available in all settings and increases radiation exposure for both the patient and those in the operating room. 4 , 5 , 6 Other techniques for cam osteoplasty include computer-navigated resection, which requires optical tracking markers to be placed into the femur, calibration to tracking equipment, and C-arm fluoroscopy. 7 These techniques all still include further use of intraoperative imaging and do not address all of the limitations associated with fluoroscopy.…”

Effect of cam resection depth on clinical outcomes after primary hip arthroscopy

“…In the present study, patients who had not reached PASS for mHHS had a mean resection depth of 4.5 mm. A study reported by Mortensen et al 14 advocated using sclerotic subchondral cortical bone as a guide for the amount of resection of the cam lesion by utilising intraoperative fluoroscopy imaging.…”

“…It was reported that postoperative MRD of <3.15 mm was associated with higher hip scores 2-year postoperatively. A study reported by Mortensen et al 14 advocated using sclerotic subchondral cortical bone as a guide for the amount of resection of the cam lesion by utilising intraoperative fluoroscopy imaging.…”