Anterolateral Approach to the Ankle and Hindpart of the Foot

Anterolateral Approach to the Ankle and Hindpart of the Foot‌

 

 

The full extent of the anterolateral approach to the ankle and hindpart of the foot allows exposure not only of the ankle joint but also of the talonavicular, calcaneocuboid, and talocalcaneal joints. The approach is used commonly for ankle fusions, but also can be used for triple arthrodesis and even pantalar arthrodesis. In addition, it is possible to excise the entire talus through this approach, or to reduce it in cases of talar dislocation.

 

Position of the Patient

 

Place the patient supine on the operating table; place a large sandbag underneath the affected buttock to rotate the leg internally and bring the lateral malleolus forward. Exsanguinate the limb either by elevating it for

3 to 5 minutes or by applying a soft rubber bandage; then inflate a tourniquet (see Fig. 12-31).

 

Landmarks and Incision

Landmarks

Palpate the lateral malleolus at the distal subcutaneous end of the fibula.

Palpate the base of the fifth metatarsal, a prominent bony mass on the lateral aspect of the foot.

Incision

Make a 15-cm slightly curved incision on the anterolateral aspect of the ankle. Begin some 5 cm proximal to the ankle joint, 2 cm anterior to the anterior border of the fibula. Curve the incision down, crossing the ankle joint 2 cm medial to the tip of the lateral malleolus, and continue onto the foot, ending some 2 cm medial to the fifth metatarsal base, over the base of the fourth metatarsal (Fig. 12-34).

 

Internervous Plane

 

The internervous plane lies between the peroneal muscles (which are supplied by the superficial peroneal nerve) and the extensor muscles (which are supplied by the deep peroneal nerve; see Figs. 12-58 and 12-

61).

 

Superficial Surgical Dissection

 

Incise the fascia in line with the skin incision, cutting through the superior and inferior extensor retinacula. Do not develop skin flaps. Take care to identify and preserve any dorsal cutaneous branches of the superficial peroneal nerve that may cross the field of dissection (Fig. 12-35). Identify the peroneus tertius and extensor digitorum longus muscles, and, in the upper half of the wound, incise down to bone just lateral to these muscles (Fig. 12-36).

 

Deep Surgical Dissection

 

Retract the extensor musculature medially to expose the anterior aspect of the distal tibia and the anterior ankle joint capsule. Distally, identify the extensor digitorum brevis muscle at its origin from the calcaneus (Fig. 12-37) and detach it by sharp dissection. During dissection, branches of the lateral tarsal artery will be cut; cauterize (diathermy) these to prevent the formation of a postoperative hematoma. Reflect the detached extensor digitorum brevis muscle distally and medially, lifting the muscle fascia and the subcutaneous fat and skin as one flap. Identify the dorsal capsules of the calcaneocuboid and talonavicular joints, which lie next to each other across the foot, forming the clinical midtarsal joint (see Fig. 12-60). Next, identify the fat in the sinus tarsi and clear it away to expose the talocalcaneal joint, either by mobilizing the fat pad and turning it downward or by excising it. Preserving the fat pad prevents the development of a cosmetically ugly dimple postoperatively. Preserving the pad also helps the wound to heal (Fig. 12-38).

Finally, incise any or all the capsules that have been exposed. To open the joints, forcefully flex and invert the foot in a plantar direction (see Fig. 12-38).

 

 

Dang

 

 

The deep peroneal nerve and anterior tibial artery cross the front of the ankle joint. They are vulnerable if dissection is not carried out as close to the bone as possible (see Fig. 12-58).

How to Enlarge the Approach

Extensile Measures

The approach can be extended proximally to explore structures in the anterior compartment of the leg. Continue the incision over the compartment, and incise the thick deep fascia in line with the skin incision. The approach also can be extended distally to expose the tarsometatarsal joint on the lateral half of the foot. Continue the incision over the fourth metatarsal, and expose the subcutaneous tarsometatarsal

joints.

 

 

 

Figure 12-34 Incision for the anterolateral approach to the ankle. Make a 15-cm

slightly curved incision on the anterolateral aspect of the ankle. Begin approximately 5 cm proximal to the ankle joint and 2 cm anterior to the anterior border of the fibula. Curve the incision downward to cross the ankle joint 2 cm medial to the tip of the lateral malleolus, and continue onto the foot, ending about 2 cm medial to the fifth metatarsal.

 

 

 

Figure 12-35 Incise the deep fascia and the superior and inferior retinacula in line with the incision. Take care to preserve the superficial peroneal nerve.

 

 

Figure 12-36 Identify the peroneus tertius and the extensor digitorum longus muscles, and incise down to bone lateral to them in the upper half of the wound.

 

 

Figure 12-37 Retract the extensor musculature medially to expose the anterior aspect of the distal tibia and ankle joint. Identify the origin of the extensor digitorum brevis.

 

 

 

Figure 12-38 The extensor digitorum brevis has been detached from its origin and reflected distally. The fat pad covering the sinus tarsi has been detached and reflected downward. Incise the joint capsules that have been exposed