Minimally Invasive Bone Grafting of Cysts of the Femoral Head and Acetabulum in Femoroacetabular Impingement: Arthroscopic Technique and Case Presentation

(A) Anteroposterior pelvic radiograph in case 1. (B) On the magnified view, a fibrocyst is visible on the anterolateral femoral neck (arrow). Three clinically important outlines can be seen: the anterior acetabular wall (red dots), the posterior acetabular wall (blue dots), and the ischial spine projection into the pelvis (green dots). (C) A preoperative frog lateral radiograph of the hip shows the fibrocyst (arrowhead) in the anterior femoral head-neck junction.

(A and B) The technique for arthroscopic bone grafting depends on the use of a metal arthroscopic cannula being passed into the graft material with multiple passes. (C) Subsequently, the graft is compressed into the cannula by use of a switching stick. (D) A slotted cannula can be used to pass the loaded arthroscopic cannula into the joint.

The femoral neck cyst of the left hip in case 1 underwent bone grafting through an arthroscopic technique. The patient was in the supine position. (A) The arthroscope was introduced from the anterior paratrochanteric portal, and the bone graft cannula filled with the bone graft material was introduced from the direct anterior portal. (B) After removal of the cannula, the bone graft material can be clearly seen filling the cyst completely.

At the latest follow-up visit at 20 months, (A) anteroposterior and (B) lateral radiographs of case 1 showed an improved femoral head contour and increased bone density in the femoral head-neck cyst.

Preoperative anteroposterior radiograph in case 2 showing an acetabular bone cyst (dots), ossification of the acetabular labrum (black arrow), and early osteoarthritis with increased bone density in the acetabular roof (white arrow).

Arthroscopic images in case 2 in the supine position as viewed from the direct anterior portal showed (A) an acetabular bone cyst (black arrowheads) with the contents removed with a small curette. (B) After removal of the cyst contents, (C) the metal cannula with the bone graft materials was introduced through the anterior paratrochanteric portal through the slotted cannula. (D) The cyst cavity was filled with the bone graft material.