Anterolateral approach to ankle and tarsus

Introduction

• Allows exposure of the ankle joint, the talonavicular, calcaneocuboid, and talocalcaneal joints

Indications

• Ankle fusions
• Triple arthrodesis and pantalar arthrodesis
• Excision of the entire talus, or to reduce it in cases of talar dislocation

Position of patient

• Patient is placed supine on the operating table, with a sandbag underneath the affected buttock

Landmarks and incision

Landmark

• Palpate the lateral malleolus and the base of the 5th metatarsal

Incision

• Begin 5 cm proximal to the ankle joint, 2 cm anterior to the anterior border of the fibula
• 15-cm in length slightly curved on the anterolateral aspect of the ankle down
• Cross the ankle joint 2 cm medial to the tip of the lateral malleolus, and continue on the foot
• End some 2 cm medial to the 5th metatarsal  base, over the base of the 4th metatarsal

Internervous plane

• Lies between the peroneal muscles (superficial peroneal nerve) and the extensor muscles (deep peroneal nerve)

Superficial dissection

• Incise the deep fascia with the superior and inferior retinaculum in line with the incision; preserves the superficial peroneal nerve
• Do not develop skin flaps
• Incise down to bone lateral to the peroneus tertius and the extensor digitorum longus muscles in the upper half of wound

Deep dissection

• Expose the anterior aspect of the distal tibia and the anterior ankle joint capsule by retracting the extensor musculature medially
• Identify the extensor digitorum brevis muscle distally and sharply detach it from its calcaneal origin while cauterizing branches of the lateral tarsal artery
• 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
• Mobilize the fat pad in the sinus tarsi either by turning it downward or by excising it to expose the talocalcaneal joint
• To open the joints, forcefully flex and invert the foot in a plantar direction after opening the joints capsule

Dangers

• Crossing the front of the ankle joint are the deep peroneal nerve and the anterior tibial artery
• Dissection is carried out as close to the bone as possible

How to enlarge the approach

Proximal

• Incise the thick deep fascia in line with the skin incision to explore structures in the anterior compartment of the leg

Distal

• Continue the incision over the fourth metatarsal to expose the subcutaneous tarsometatarsal joints on the lateral half of the foot

Figures