Dorsal Approach to the Lesser Metatarsals

What it exposes. The dorsal approach gives direct, extensile access to the shafts, necks and heads of the second to fifth metatarsals, from the tarsometatarsal joint proximally to the metatarsophalangeal joint distally. It is the workhorse exposure for forefoot reconstructive surgery and central-ray trauma. Why dorsal. The approach is superficial and relatively bloodless under tourniquet, exploits the natural interval between the extensor tendons, and allows one incision to address two adjacent rays when placed in the intermetatarsal space. No major motor nerve is at risk, and the incision can be extended proximally or distally as required. The plantar approach is rarely used for the lesser metatarsals because it crosses weight-bearing skin and gives poorer access; the medial approach is reserved for the first ray and the lateral approach for the fifth metatarsal base. Primary indications - Weil osteotomy for lesser metatarsalgia and metatarsal length abnormalities

• Open reduction and internal fixation of central-ray metatarsal fractures (neck, shaft or head)
• Surgical management of Freiberg disease (infraction of the lesser metatarsal head)
• Metatarsal head resection for intractable plantar keratosis or Freiberg collapse
• Partial or complete ray amputation for infection, tumour or severe deformity
• Revision surgery for malunion, non-union or a failed previous osteotomy Contraindications and alternatives - Active infection in the skin over the planned incision (consider staging or an alternative)
• Severe peripheral vascular disease with a non-palpable dorsalis pedis pulse (assess perfusion first)
• Previous surgery with extensive scarring that would require a different plane
• Isolated first ray pathology (use the medial approach instead) Approach variants - Single ray — a longitudinal incision directly over one metatarsal, for an isolated fracture or a single Weil osteotomy.
• Two-ray access — one incision placed in the intermetatarsal space between adjacent metatarsals, for a Weil osteotomy of two rays or a central fracture.
• Extended proximal — extended to the tarsometatarsal joint, for Lisfranc involvement or proximal fractures. Position and landmarks. Position the patient supine on a radiolucent table with a thigh or calf tourniquet applied before exsanguination, and place the foot at the very end of the table so the C-arm can obtain true AP, oblique and lateral views of the forefoot from the opposite side without obstruction. Inflate the tourniquet to 250-300 mmHg after exsanguination, slightly plantarflex the ankle to relax the extensor tendons, and pad all pressure points. Palpate and mark the metatarsal heads (palpable on the plantar aspect with dorsal projections), trace the shafts proximally to the tarsometatarsal joints, note the course of superficial dorsal veins to avoid them, and mark the incision directly over the target metatarsal or in the intermetatarsal space. Keep tourniquet time to less than 90 minutes where possible, as prolonged inflation increases the risk of nerve palsy and muscle damage; in patients with peripheral vascular disease consider operating without a tourniquet.

Work down through the layers along the dorsum of the forefoot, protecting the dorsal cutaneous nerves in the subcutaneous plane, retracting the extensor tendons, and then dissecting strictly subperiosteally on bone to the neck and head.

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Structures at risk, by layer

Extensile options. Extend proximally to the tarsometatarsal joint to access the metatarsal base or the Lisfranc joint complex — useful for proximal shaft fractures, Lisfranc injuries involving the central rays, or a proximal osteotomy. Distal extension is limited by the toe: for head access the incision stops at the metatarsophalangeal joint crease, and further distal exposure needs a separate toe incision or a plantar approach. The interosseous muscles are not violated unless a ray amputation is planned. Closure. Close in layers: reapproximate the periosteum over the osteotomy or hardware where possible, close the fascia loosely to avoid compartment syndrome, allow the extensor tendons to fall back into position, close the subcutaneous layer carefully to avoid catching the dorsal cutaneous nerves, and close the skin with interrupted nylon or absorbable suture. Apply a sterile compressive dressing. Weight-bearing status depends on the procedure — non-weight-bearing for 4 to 6 weeks after a Weil osteotomy or fracture fixation, protected weight-bearing earlier after head resection — with early toe range of motion once wounds are stable, and serial radiographs to monitor healing and length maintenance.

• Weil osteotomy — distal oblique metatarsal osteotomy for lesser metatarsalgia and length correction.
• ORIF of central-ray metatarsal fractures — neck, shaft or head fixation with mini-fragment plates or K-wires.
• Surgical management of Freiberg disease — metatarsal head resection or osteochondral grafting with minimal periosteal stripping.
• Partial or total ray amputation for infection, tumour or severe deformity.
• Excision of intractable plantar keratosis, elevation and grafting of depressed articular fragments, and debridement of osteomyelitis or non-union.