Palmar approach to the scaphoid
1. Indications
This approach is indicated for the following injuries:
- Irreducible, displaced scaphoid fractures, in the distal two thirds
- Comminuted fractures
2. Angled skin incision
The landmarks for this incision are:
- The scaphoid tubercle
- The flexor carpi radialis (FCR) tendon
The incision line can be marked on the skin in line with the FCR tendon, starting at the scaphoid tubercle, and running proximally for about 2 cm. Distal of the scaphoid tubercle, the incision angles towards the base of the thumb, over the scaphotrapezial joint.
3. Zigzag incision
Alternatively, a zigzag incision may be constructed using the same landmarks.
4. Ligate superficial palmar branch of radial artery
The superficial palmar branch of the radial artery passes towards the palm, running close to the scaphoid tubercle. If necessary, it can be ligated and divided.
5. Open the FCR sheath
The FCR sheath is opened as far distally as possible, and the tendon retracted towards the ulnar side.
6. Exposure of the wrist capsule
The capsule is then incised obliquely from the tubercle distally towards the palmar rim of the radius proximally.
As determined by the fracture configuration, preserve as much of the palmar ligament complex as possible, as it helps to contain the proximal pole and prevent palmar tilt of the scaphoid.
7. Expose the scaphoid
Retract the divided radioscaphocapitate ligament to expose the scaphoid.
If it is necessary to expose the proximal part of the scaphoid, divide the long radiolunate ligament, proximally as far as the palmar rim of the radius.
8. Exposure of scaphotrapezial joint
The scaphotrapezial joint must be exposed to allow optimal positioning of a screw.The incision is deepened distally, dividing the origin of the thenar muscles in line with their fibres.
The scaphotrapezial joint is identified, the scaphotrapezial ligament divided in the line of its fibers, and the joint capsule opened.
9. Wound closure
The divided palmar ligaments (radioscaphocapitate/long radiolunate) must be repaired with fine interrupted sutures in order to prevent secondary carpal instability.
Approximate the soft tissues over the scaphotrapezial joint.
Test the integrity of the soft-tissue repair by passive wrist motion.
Finally, the FCR tendon sheath is repaired and covered with subcutaneous tissue.
