2015- Domb et al. Technique of Arthroscopically Assisted Transtrochanteric Drilling for Femoral Head Chondral Defects

Sivashankar Chandrasekaran, M.B.B.S., F.R.A.C.S., Dror Lindner, M.D., Timothy J. Martin, M.A., Parth Lodhia, M.D., Carlos Suarez-Ahedo, M.D., and Benjamin G. Domb, M.D.

Abstract: Microfracture is a marrow-stimulation technique in which damaged cartilage is drilled or punched, perforating the subchondral bone and generating a blood clot within the defect that matures into fibrocartilage. Microfracture for the treatment of small cartilage defects of the hip has shown good results. Arthroscopic procedures are less invasive than open procedures and have a reduced incidence of complications such as infection or avascular necrosis of the femoral head. Furthermore, arthroscopic procedures allow for a shorter recovery time, resulting in not only lower overall treatment costs but also higher patient satisfaction.

Medial and parafoveal cartilage defects of the femoral head can be challenging to effectively microfracture using standard arthroscopy portals because of the acute angles required for instrument manipulation. This report describes a technique for microfracturing these challenging areas of the femoral head using a 2.7-mm K-wire and drilling in a transtrochanteric direction using arthroscopic and imaging guidance to target the area of chondral damage.

Chondropathies of the acetabulum and femoral head not only are a frequent cause of pain and functional limitation but also, if not adequately treated, may progress to joint arthrosis. Arthroscopic or open approaches may be used to access the area of chondral damage. Open approaches often require a surgical hip dislocation, which has an increased risk of infection and avascular necrosis of the femoral head, in addition to increased recovery time and longer hospitalization.

Surgical techniques available for the repair of chondral defects include debridement, microfracture, autologous chondrocyte implantation, and osteochondral transplantation. Chondroplasty is the treatment of choice for partial-thickness defects with the aim of debriding the defect to remove any damaged cartilage and creating a smooth surface. Microfracture is the standard of care for full-thickness chondral defects. Microfracture involves drilling or punching the cartilage defect to penetrate the subchondral bone so that blood and bone marrow are released into the defect, initiating repair with fibrocartilage.