Fig. 1.

Intraoperative images of the surgical technique showing a collagen membrane in a chondral patellar lesion. (A) Incision site and medial parapatellar arthrotomy. (B) Kirschner wire used as a ‘joystick’ to evert the patella. (C) Identification and debridement of the chondral lesion. (D) Debrided and microperforated receptor area. (E) Metallic template used to measure the dimension of the lesion. (F) Metal mold cut, together with the membrane. (G) Membrane suture in the cartilage with absorbable No. 5.0 suture. (H) Fibrin glue used at the edges of the lesion. (I) A final view of the procedure showing the osteochondral defect covered and secured by the collagen membrane.