Fig 1.

(A) Arthroscopic view from the modified anterior portal showing a full-thickness chondral lesion of the right superior acetabulum (11- to 2-o'clock position) undergoing debridement with an arthroscopic shaver in preparation for graft placement. The indications for microfracture for this lesion included Outerbridge grade IV, an area of approximately 120 mm², and no evidence of surrounding diffuse chondromalacia. Adequate vertical margins are established with an arthroscopic biter before microfracture is performed to provide containment of the marrow clot and graft. The patient is positioned supine. (B) Arthroscopic view of the full-thickness chondral lesion in the same patient after completion of lesion preparation, showing vertical margins circumferentially (arrow). (C) Arthroscopic view of the prepared full-thickness chondral lesion in the same patient showing the use of a 90° arthroscopic awl to make microfracture holes. (FH, femoral head.)