Scaphoid Open Reduction and Internal Fixation Through Dorsal Approach

CHAPTER 1

Scaphoid fractures are common fractures of the wrist that often require surgical repair with internal fixation. Common indications for internal fixation of a scaphoid fracture include: displaced or comminuted fracture of the scaphoid, proximal pole fractures of the scaphoid, scaphoids with a delayed diagnosis, or scaphoid fractures with delayed healing or non-unions. When indicated for surgery, fractures of the scaphoid can be approached volarly or dorsally. This is a case of a proximal pole scaphoid fracture treated through a dorsal approach.

CHAPTER 2

After the operative limb is prepped and draped, the incision is marked. First, Lister's tubercle is identified by palpation. The incision is placed just distal and ulnar to Lister's tubercle to allow identification of the EPL tendon and the interval between the second and fourth compartments. The surgical incision site is then injected with a local anesthetic. The limb is then exsanguinated, and the tourniquet is inflated.

CHAPTER 3

The incision is placed, and then blunt dissection is performed down to the level of the extensor retinaculum.

CHAPTER 4

Once blunt dissection has been achieved down to the level of the extensor retinaculum, the distal aspect of the extensor retinaculum just distal to Lister's tubercle is released until the EPL tendon is in the field. Once the EPL tendon is identified and protected, the interval distal to it between the second and fourth compartments is developed.

CHAPTER 5

With the EPL tendon identified and protected and the joint capsule exposed, an inverted-T arthrotomy of the capsule is performed. Care must be taken to avoid injury of the EPL tendon proximally, the ECRB tendon radially, and the EDC tendons ulnarly. Also, deep dissection with a knife should be avoided to avoid inadvertent injury to the scaphoid lunate ligament. It is typical for a joint hemarthrosis to be identified in the setting of an acute fracture as shown here. Once the arthrotomy is performed and the joint washed out, the base of the scaphoid should become readily apparent as shown here. The fracture line is also apparent.

CHAPTER 6

With the fracture reduced and the base of the scaphoid exposed, the guidewire for the headless screw is placed at the center of the base of the scaphoid just radial to the scaphoid lunate ligament as shown here. The trajectory for the guidewire being placed antegrade in the scaphoid should be in line with the thumb ray in all planes. Using a wire driver, the guidewire is then advanced antegrade down the center of the scaphoid as shown here. Note how the wrist is held in a flexed posture during insertion of the guidewire. With the aid of an image intensifier, a center-center position of the guidewire within the scaphoid is confirmed on PA, oblique, and lateral views as shown here.

CHAPTER 7

Once satisfied, the screw is placed following the manufacturer's guide for that headless compression screw. Here the guidewire is being measured with a cannulated depth gauge.

Next, the cannulated drill is placed over the guidewire. This creates the path for the headless compression screw. The drill is advanced in oscillation to avoid binding any tissue or tendons as well as to avoid cutting the pin within the scaphoid. It is advanced up to the distal subchondral bone of the scaphoid but does not cross into the ST joint.

Next, the cannulated headless compression screw is placed over the guidewire. Typically, the length of the screw is 16 to 24 mm based on the size of the patient or the length of the scaphoid. It is advanced slowly over the guidewire making sure to be adequately countersunk in the proximal pole of the scaphoid while not being too proud or violating the distal pole of the scaphoid or the ST joint distally.

Screw position is then confirmed on the image intensifier, again making sure that the screw is placed down the center of the scaphoid and that it is adequately countersunk proximally but not proud distally.

CHAPTER 8

Once satisfied, the closure is undertaken. The wound and joint is washed out. Next, the capsule is closed. The EPL tendon is identified and retracted. Care is taken to avoid capturing any of the extensor tendons inadvertently in the capsule or closure. Finally, the skin is closed, and a bulky dressing, and/or splint, and/or cast is applied. Thank you.