[Free vascularized iliac bone graft for the treatment of scaphoid nonunion with avascular proximal fragment]

Abstract

Objective: The goal of the procedure is osseous healing of the scaphoid in an anatomic position and replacement of necrotic bone at the site of the scaphoid nonunion by a vascularized iliac bone graft.

Indications: Scaphoid nonunion with necrotic fragment in SNAC (scaphoid nonunion advanced collapse) < 1. Nonunion following previous surgery.

Contraindications: Pattern of advanced carpal collapse (SNAC > 1). Malformation, disease or previous injury of the vascular system. Poor compliance. Reduced general health.

Surgical technique: Principles of the surgical technique according to Pechlaner et al.: harvesting of a corticocancellous bone graft from the anterior iliac crest with a nutrient vascular bundle from the deep circumflex iliac artery, debridement of the necrotic scaphoid, press-fit fixation of the tailored graft, pin fixation, and microvascular anastomosis to the radial artery.

Postoperative management: Fixation in an upper-arm cast for 4 weeks, followed by lower-arm cast fixation including the thumb to the interphalangeal joint until week 12. Physiotherapy. Wrist splinting in patients enforced to heavy manual load.

Results: The described procedure has been practiced at the own institution since 1985 and evaluated in different studies. Using a free vascularized iliac bone graft, union could be achieved in 85% of patients with avascular scaphoid nonunion and in 80% with avascular proximal pole nonunion. The nonunion can be bridged in 93% following failed previous scaphoid screw fixation.