Surgical Procedure
A curved skin incision of 6-7 cm is made along the medial malleolus.
Two screw holes are predrilled from distal to proximal in the medial malleolus.
After placement of the retractors, a medial malleolar osteotomy is created to expose the osteochondral defect. To be sure of the angle of the medial malleolar osteotomy, use an arthroscopic probe to identifiable the ankle joint behind the medial malleolus.
Utilizing the drill guide, a guide pin is placed into the center of the defect, pependicalar to the medial talar curvature.
Place the cannulated drill over the guide pin and drive until the proximal shoulder of the drill is flush with the articular surface.
Pearls & Pitfalls
Video
The second video shows a second look arthroscopy one year after placement of a hemicap. The hemicap is almost completely covered with (fibro-)cartilage
Pearls
To be sure of the angle of the medial malleolar osteotomy, use an arthroscopic probe to identify the ankle joint behind the medial malleolus. (van Bergen, Arch Orthop Trauma Surg. 2011 Jul)
Pitfalls
Make sure not to place the HemiCAP in level of the cartilage or above, to prevent contact pressure on the distal tibia.