Access to the metatarsophalangeal joint of the little toes

Introduction

The approach to the metatarsophalangeal (MTP) joint of the little toes provides access to the MTP joints of the second, third, fourth, and fifth toes while avoiding incisions on the sole of the foot.

Indications for the Approach

The approach to the MTP joint of the little toe can be used for procedures such as:

1. Resection of the metatarsal heads
2. Osteotomy of the distal metatarsal
3. Partial proximal phalangectomy
4. Fusion of the metatarsophalangeal joints (rare)
5. Capsulotomy of the metatarsophalangeal joints
6. Muscle tenotomy
7. Neurectomy

Patient Positioning

Place the patient supine on the operating table with a bolster under the thigh to flex the knee and keep the foot plantigrade on the table.

Landmarks and Incisions

Landmarks

• The metatarsal head of the toe
• The tendons of the extensor digitorum longus muscle

Incision

• Make a 2–3 cm longitudinal incision over the dorsolateral aspect of the affected metatarsophalangeal joint. The incision should run parallel to, but just lateral of, the long extensor tendon.
• If two adjacent joints need to be exposed, make the incision between them. Alternatively, a transverse dorsal incision can be made over the joints.

Internervous Plane

• There is no internervous plane for the approach to the MTP joint of the little toe.
• The approaches lie well dorsal to the plantar nerves and vessels, the main neurovascular structures in this area.
• Take care not to cut the dorsal digital nerves, as their branches may cross the operative field.

Superficial Dissection

• Incise the deep fascia in line with the skin incision and retract the long extensor tendon to expose the dorsal aspect of the metatarsophalangeal joint.
• An extensor tenotomy or lengthening is often performed simultaneously with the joint surgery.
• In this case, divide the extensor tendon in a Z-shape rather than retracting it. When exposing two joints, retract the tendon laterally to gain access to the adjacent joint.

Deep Dissection

A longitudinal incision in the dorsal capsule of the metatarsophalangeal joint provides entry into the joint.

Extension of the Approach

The approach is rarely extended and is mainly used for specific webspace pathologies.

Dangers

Structures at risk during the approach to the MTP joint of the little toe include:

1. Digital nerve and vessels.

References

• Surgical Exposures in Orthopaedics – 4th Edition
• Campbell’s Operative Orthopaedics, 12th Edition