The operating room must be large enough to accommodate all personnel as well as the arthroscopy tower and, when necessary, fluoroscopy. It should have the necessary equipment for general, regional, or local anesthesia, and suction should be calibrated appropriately for the type of motorized instruments used. The arthroscopy tower should be mobile, allowing the procedure to be transferred to another room if needed. Its components include the video monitor, video camera, powerbox, light source, digital recorder, and digital printer if one is used (Fig. 4-1).

Ankle arthroscopy can be performed in three different positions: in the supine position using a thigh and ankle holder, in the lateral decubitus position using a bean bag, and using a leg holder with the foot of the table bent at 90°.

We prefer the supine position using general or regional anesthesia, supplemented by a popliteal block (Chap. 6). Local anesthesia is not recommended except for diagnostic purposes. If general anesthesia is used, the patient should be paralyzed to allow easier distraction and visualization whenever possible. After appropriate anesthesia is administered, a suitable antibiotic is given intravenously. A tourniquet is applied to the upper thigh before preparing and draping the leg, and a well-padded thigh support is used to secure the thigh in about 45° of hip flexion. The thigh support is placed proximal to the popliteal fossa to prevent injury to the neurovascular structures. The patient is then rolled slightly clockwise until the center of the knee and ankle are pointed straight to the ceiling. A post is placed against the greater trochanter, proximal to the thigh support to prevent external rotation of the hip (Fig. 4-2). The table pad at the foot of the bed is removed to give the surgeon better access to the posterior hindfoot, and the nonoperated leg is placed on well-padded blankets to prevent neurovascular injury (Fig. 4-3A, B). The operated extremity is then prepared and draped. A sterile clamp is attached to the table over the drapes, and the sterile foot holder is used for invasive distraction before applying the tibial and calcaneal pins. When noninvasive distraction is used, a metal bar is inserted through the distractor and attached to a sterile
clamp (Fig. 4-4). With this setup, the surgeon can sit or stand during the surgery, and both the anterior and posterior portions of the ankle are easily accessible without further manipulation of the patient’s extremity.

The medial malleolus, distal tibia, and fibula are outlined. A perpendicular line is drawn from the tip of the fibula to the Achilles; a second line parallel to this is drawn 1.2 cm proximal to the tip of the fibula to reference the location of the posterolateral portal. The dorsalis pedis pulse should be carefully palpated and its position marked. Likewise, the saphenous vein and the anterior tibial tendon are marked over the surface of the ankle.

Marking the superficial peroneal nerve branches is particularly important: this is the structure most at risk for injury when the anterolateral portal is created. This identification is facilitated by holding the foot in plantar flexion and inversion. The nerve can usually be palpated anterior and distal to the lateral malleolus. The nerve is marked prior to prepping the leg, since it is easier to feel and see, and re-marked after draping. The joint line is identified by palpation in flexion and extension of the ankle (Fig. 4-5A, B).

Without distraction, it is difficult to place a rigid arthroscope over a curved structure, such as the dome of the talus, without scuffing the cartilage or breaking the instrument. With distraction, the arthroscope can be more easily manipulated posteriorly without damage to the tissues or equipment (Fig. 4-6). Various joint-distraction techniques have been described to improve visualization and ease of access for operative instrumentation.¹, ², ³ Both noninvasive soft tissue distraction and invasive mechanical distractors may be used. With improved noninvasive instrumentation, adequate visualization is possible without invasive techniques in almost all cases.