For routine ankle arthroscopy, place the patient supine, with the operative extremity in a leg holder such that the hip and knee are flexed, with the foot hanging free, resulting in gravity-assisted distraction. This also allows free ankle range of motion, which can assist in access to different parts of the ankle (Fig. 50-1).

Mark portal placement after establishing the path of the superficial peroneal nerve, which can be seen subcutaneously after plantar flexion and inversion of the foot (Fig. 50-2).

Mark anterolateral and anteromedial portals at the joint line, which can be palpated, staying away from the peroneal nerve (Fig. 50-3).

After Esmarch exsanguination of the extremity and inflation of the thigh tourniquet, establish the anteromedial portal by inserting an 18-gauge spinal needle at the marked site and insufflating the joint with saline to ensure intraarticular placement and to provide more space for introduction of the blunt trocar (Fig. 50-4). Successful insufflation occurs when there is minimal resistance to the introduction of saline, when the foot dorsiflexes as the joint capsule becomes tight, and when there is backflow of the saline into the syringe after the joint is maximally distended. The anteromedial portal is established first, because there are fewer structures at risk than with the anterolateral portal.

After localization of the anteromedial portal with the spinal needle, make a skin incision just large enough to insert the cannula. A large incision allows more extravasation of fluid into the surrounding soft tissues and can make the procedure more difficult.

Further penetrate the joint with a blunt straight hemostat to avoid damage to the saphenous nerve, which is at risk in this area.

Place a 2.7-mm 30-degree arthroscope into the anteromedial portal, and establish the anterolateral portal by direct visualization of a spinal needle introduced at the site of the anticipated portal placement.

When appropriate needle placement is seen, make the skin incision for the anterolateral portal and penetrate the joint with a blunt instrument (Fig. 50-5); then introduce the arthroscopic shaver in this portal.

Inspect the lateral aspect of the joint with use of instruments in the anterolateral portal as needed for débridement (Fig. 50-6), and then switch portals (arthroscope in the anterolateral portal and instruments in the anteromedial portal) for treatment of the medial side of the joint (Fig. 50-7).

Noninvasive distraction can be used if needed to access the deeper aspects of the joint (Fig. 50-8). Occasionally, a posterolateral portal is needed to treat pathological processes in the posterior aspect of the ankle that cannot be reached even after distraction is applied.

After the procedure is completed, close the portals with suture to avoid the development of a fistula, which is a reported complication of ankle arthroscopy.

Place the patient prone with the foot at the end of the bed and a support under the lower leg so that the foot hangs freely (Fig. 50-10A). Keeping the foot in neutral with respect to dorsiflexion/plantar flexion and varus/valgus is the safest position in which to avoid neurovascular damage.

Make the posterolateral portal just superior to a line from the tip of the lateral malleolus to the Achilles tendon, just lateral to the tendon (Fig. 50-10B). Insert a hemostat through a small skin incision, aiming along a line directed to the first web space of the forefoot, until it hits bone (Fig. 50-10C).

Make the posteromedial portal at the same level, just medial to the Achilles tendon, and insert a hemostat through the skin incision, directing it to contact the arthroscope at a 90-degree angle (Fig. 50-10D). Once the hemostat contacts the arthroscope, move it down the shaft until it hits bone and can be seen through the scope. If desired, use fluoroscopy to confirm appropriate placement.

Place a shaver in this portal and remove the posterior subtalar capsule (Fig. 5-10E). Take care to stay lateral to the flexor hallucis longus tendon to avoid damage to the neurovascular bundle (Fig. 5-10F).

To remove the os trigonum, partially detach the posterior talofibular ligament and posterior talocalcaneal ligament and release the flexor retinaculum to expose the bone to be removed (Fig. 50-10G).

If distraction is needed, a transcalcaneal traction pin can be hooked to a traction device.

The setup for subtalar arthroscopy is similar to that for ankle arthroscopy, with the operative extremity placed in a leg holder, the hip and knee flexed, and the foot hanging free. Alternatively, the patient can be placed in the lateral decubitus position with the foot hanging off a bump.

After insufflation of the joint, establish the central portal and then the anterolateral portal by direct visualization using a spinal needle (Fig. 50-13).

Often, visualization of the joint is difficult when the arthroscope first enters the joint because of the synovitis that fills the sinus tarsi (Fig. 50-14A). After triangulation to place portals, continue débridement until the joint can be visualized.

Débride the anterior aspect of the posterior facet, including the often attenuated interosseous talocalcaneal ligament (Fig. 50-14B).

Rotate the instruments to the lateral aspect of the posterior facet where débridement of synovitis often is necessary (Fig. 50-15). Switch portals as needed for better access. Occasionally, a posterolateral portal is necessary for posterior access.

The subtalar joint can also be approached through posterior portals, similar to that described for posterior ankle arthroscopy.

Place the patient supine, and place a finger trap on the hallux for distraction; suspend the foot from a tower such as those used for wrist arthroscopy (Fig. 50-17A).

Make portals on either side of the extensor hallucis longus tendon at the level of the joint (Fig. 50-17B).

Use a 1.9-mm arthroscope and 2.0-mm shavers as needed.