Treatment of Nonunion of Scaphoid Waist with Ni-Ti Shape Memory Alloy Connector and Iliac Bone Graft

After fracture, the unique anatomy and blood supply of the scaphoid itself predisposes to nonunion. Scaphoid nonunion present a formidable challenge to surgeons because of the difficulties for fixation, and failure rate after treatment was very high. The Ni-Ti shape memory alloy can provide compressive stress at the nonunion site, which is the key point for bone healing. So we designed a shape memory bone connector named arched shape-memory connector (ASC). We conducted a retrospective study looking at the union rate, complications and correlating the outcome of treatment with this device. The study reviewed a cohort of 6 consecutive patients with scaphoid waist nonunion treated with ASC and illiac cancellous bone grafting at our center from August 2002 to December 2007. The patients with nonunion achieved a 100% union rate. All the patients who achieved union had good pain relief and improved function. Our study demonstrates that scaphoid waist nonunions can be successfully treated by arched shape-memory connector and illiac bone grafting.