36 Arthroscopic Microfracture and Drilling for Osteochondral Lesions of the Talus • Osteochondral lesions of the talus (OLTs) are a somewhat uncommon injury to the ankle but can often be associated with other pathologies such as ankle sprains, chronic instability, and ankle fractures.1,2 • Majority of OLTs are traumatic in nature. • The medial side of the talus is most commonly involved. • Most OLTs are within the equatorial zone of the talus. • Most success in patients with lesions <107.4 mm2 in area and/or 10.2 mm in diameter3–6. • Frequently has a history of a twisting/spraining injury to the ankle. • Complaint of activity-related pain, catching and giving way of the ankle. • Nonspecific clinical examination: • Plain radiographs may show a fracture, loose body, or cavity in the area of OLT. • Utilize X-ray, magnetic resonance imaging, and computed tomographic scans to best understand the osteochondral lesion prior to surgery. Each modality can offer insight into the staging of the lesion and knowledge of the cartilage, subchondral and bony anatomy, location, and pathology. • Brace immobilization. • Activity modification. • Nonoperative management with biologic adjuncts, pharmacotherapy, and immobilization with constant range of motion exercises. • Lavage and debridement with or without drilling and microfracture. • Open ankle arthrotomy with or without osteotomy. • Repair of an acute defect. • Osteochondral autograft. • Osteochondral allograft. • Matrix-induced autologous chondrocyte implantation (MACI). • Juvenile cartilage allograft. • Allograft cartilage extracellular matrix. • Metal resurfacing implant. • >107.4 mm2 in area and/or 10.2 mm in diameter. • Large cysts under the osteochondral lesion. • Degenerative joint disease. • Failed previous microfracture. • Restore the cartilaginous anatomy of the surface of the talus. • Arthroscopic-only treatment. • Higher rate of success with the correct indications. • No bridges burned to do other procedures in the future. • Stimulate the bone marrow and remove any loose or unstable bone or cartilage. • Allow for mesenchymal stem cells to create a clot at the lesion to assist in the formation of fibrocartilage (type I) and small amounts of type II cartilage for the noncystic and smaller lesion of the talus. • Remove pad from the end of operative table for better access to posterior portals. • Nonoperative leg on well-padded area, stabilized with a strap, and heel should be at table’s edge. • Supine with the thigh secured in a well-padded nonsterile thigh holder. • Knee flexed at 65 degrees with popliteal fossa free and patella and ankle facing ceiling. • Nonsterile tourniquet placed on proximal thigh. • Thigh post at greater trochanter. • Water should be gravity on the same side as the operative ankle. • Mark out the superficial peroneal nerve before prepping and draping the patient. Fig. 36.1 The thigh is supported by a well-padded holder attached via a clamp to the rail of the table. The tourniquet is placed around the proximal thigh and the thigh support itself is placed proximal to the popliteal fossa to avoid injury to the neurovascular structures. • After distraction, the anterior tibialis, fibula, and tibia/medial malleolus should be marked out. • Tourniquet inflation per surgeon’s preference. • Distract the joint with noninvasive strap. • Small joint arthroscopes. • 1.9-mm 30-degree arthroscope. • 2.7-mm 30-degree and 70-degree arthroscopes. • 2.9-mm associated cannulas. • 2.0-, 2.9-, and 3.5-mm shavers and burrs. • 3.5and 4.5-mm ring and cup curettes. • 1.5-mm probes. • 2.9and 3.5-mm graspers and baskets. • 2.9-mm osteotomes. • Pituitary rongeurs. • Microfracture picks. • Nanofracture picks. • K-wires (Kirschner wires; 0.045 and 0.062 inches)—smooth with trochar tips. • Noninvasive ankle distractor, thigh holder, adjustable IV pole for gravity fluid management. • 22-gauge 1.5-inch needle, 18-gauge spinal needle. • 10-mL syringe with extension IV tubing. • 2to 50-mL syringes. • General plus a popliteal block with a saphenous block placed locally by the surgeon at the conclusion of the case with 10 mL of 0.5% bupivacaine without epinephrine. • Patient should be completely “paralyzed” if possible for best distraction. • Always use the “nick-and-spread” technique to avoid neurovascular injury. • Anteromedial portal—medial to the tibialis anterior with saphenous vein and nerve, anterior tibialis tendon, and extensor hallucis longus at risk (Fig. 36.2). • Anterolateral portal—lateral to the peroneus tertius with the superficial peroneal nerve branch, extensor digitorum communis, and peroneus tertius at risk (Fig. 36.2). • Posterolateral—at the soft spot lateral to the Achilles tendon, 1.2 cm above the tip of the fibula with the sural nerve and small saphenous vein at risk (Fig. 36.3). • Transmalleolar for K-wire microfracture drilling through the fibula or tibial for entrance into the talar defect. • Establish the anteromedial portal first by inserting a 22-gauge needle just medial to the anterior tibialis tendon, which is palpated with the outside hand. Once the proper trajectory is noted with the needle aiming just superiorly over the dome, inject 10 mL of sterile saline into the joint evaluating the backflow and joint distention laterally. • Then use an 11-blade scalpel to make a vertical incision with the anterior tibial tendon palpated with the outside hand. • Dissect bluntly with the mosquito, then insert the blunt trochar with the arthroscopic cannula attached. • Once the scope is in the joint, initially use the side port of the cannula to inject fluid using the 50-mL syringes and extension tubing. • Use a 22-gauge needle to locate the anterolateral portal and with the nick-and-spread technique enter the joint and insert the inflow cannula. • Begin the initial joint assessment, then create the posterolateral portal by using a 18-gauge spinal needle at the soft spot, as described earlier, while viewing through the notch of Harty. Aim the needle 45 degrees toward the medial malleolus and just under the transverse tibiofibular ligament until there is backflow.
36.1 Introduction
36.2 Indications
36.2.1 Clinical Evaluation
Tenderness at joint line.
Location of tenderness may not correspond to that of lesion.
36.2.2 Radiographic Evaluation
36.2.3 Nonoperative Options
36.2.4 Alternate Procedures
36.2.5 Contraindications
36.3 Goals of Surgical Procedure
36.4 Advantages of Surgical Procedure
36.5 Key Principles
36.6 Preoperative Preparation and Patient Positioning (Fig. 36.1)
36.7 Operation Technique
36.7.1 Equipment
36.7.2 Anesthesia
36.7.3 Incisions/Preferred Portals
Musculoskeletal Key
Fastest Musculoskeletal Insight Engine
