Chapter 19 Arthroscopic Bone Grafting for Scaphoid Nonunion

10.1055/b-0035-121129

Chapter 19 Arthroscopic Bone Grafting for Scaphoid Nonunion

Introduction

Scaphoid fractures are often initially missed and then diagnosed only once nonunion manifests. Because the natural history of these fractures results in radiocarpal arthritis and ultimately midcarpal arthritis, they must be surgically treated. However, choice of treatment strategy is still controversial. The techniques range from less invasive, such as percutaneous fixation, to more invasive, such as autologous bone grafting from the iliac crest or vascularized bone grafts.

Surgical treatment of nonunions can be minimally invasive with arthroscopy. This simplifies postoperative recovery, reduces complications, and preserves the wrist’s capsule–ligament complex, and thus the scaphoid’s precarious vascularization.

Operative Technique

Patient Preparation and Positioning

The procedure is performed under regional anesthesia using a tourniquet. The patient’s arm is secured to an arm board. Finger traps are used to apply 5 to 7 kg of traction along the arm’s axis.

Radiocarpal and Midcarpal Exploration

The scope is introduced into the 6R portal and the shaver into the 3–4 portal. This approach allows the integrity of the scapholunate ligament to be verified. The quality of the cartilage at the proximal pole of the scaphoid and radial styloid process is also verified. If needed, radial styloidectomy can be performed arthroscopically at this point in the procedure (Chapter 6).

Arthroscopic treatment of the nonunion is performed via the midcarpal joint. The scope is introduced into the ulnar midcarpal (MCU) portal and instruments into the radial midcarpal (MCR) portal. The first phase of the arthroscopic procedure consists of complete synovectomy with a shaver.

**Fig. 19.1a, b** a Drawing of the nonunion site being palpated with a probe. b Arthroscopic view of the nonunion site viewed from the midcarpal joint.

Nonunion Site Preparation

The nonunion site will be visible or will appear as a bone fissure filled with fibrous tissue ( Fig. 19.1a, b ). This fis-sure can be located with a hook probe. The nonunion site is abraded with a curved curet, shaver, and/or bur in succession ( Fig. 19.2a, b ). The goal is to expose bleeding cancellous bone on both sides, visible by arthroscopy ( Fig. 19.3 ).