Volar approach to the scaphoid

Introduction

Indications

• ORIF of the scaphoid.
• Bone grafting for nonunion of the scaphoid.
• Excision of the proximal third of the scaphoid.
• Excision of the radial styloid.

Advantages

• Provides good exposure of the scaphoid bone.
• Avoids damaging the dorsal blood supply to the bone's proximal half, as well as the superficial branch of the radial nerve.
• Leaves a more cosmetic scar than the dorsal approach.

Disadvantage

• Poses a threat to the radial artery.

Position of patient

• The patient is placed supine on the operating table, with the forearm supinated on an arm board.
• Apply a tourniquet, then an exsanguinating bandage.

Landmarks and incision

Landmarks

• The tuberosity of the scaphoid is felt on the volar aspect of the wrist, just distal to the skin crease.
• The flexor carpi radialis muscle lies radial to the palmaris longus muscle at the level of the wrist.

Incision

• A vertical or curvilinear incision on the volar aspect of the wrist.
• 2 to 3 cm long; base it on the tuberosity of the scaphoid and extend it proximally between the tendon of the flexor carpi radialis muscle and the radial artery.

Internervous plane

• No true internervous plane; the flexor carpi radialis is mobilized (median nerve).

Superficial dissection

• Incise the deep fascia in line with the skin incision.
• Identify the radial artery on the radial side of the wound, then retract the radial artery and lateral skin flap to the lateral side.
• Identify the tendon of the flexor carpi radialis muscle distally, incising that portion of the flexor retinaculum that lies superficial to it to free the tendon from its tunnel.
• Retract the tendon of the flexor carpi radialis medially, exposing the volar aspect of the radial side of the wrist joint.

Deep dissection

• Incise the capsule of the wrist joint over the scaphoid to expose the distal two thirds of the scaphoid.
• Place the wrist in marked dorsiflexion to maximize exposure of the proximal third of the bone.

Dangers

Radial artery

• Must be identified early in the procedure, as it lies close to the lateral border of the wound and can be incised accidentally during the dissection.

How to enlarge the approach

• The incision can be extended in a limited manner. Proximally, extend the skin incision along the line of the flexor carpi radialis muscle to expose the distal end of the radius as well as radial styloid if a bone graft is planned.
• Identify the distal border of the pronator quadratus muscle and elevate from the underlying bone.

Figures