ABSTRACT
I INTRODUCTION Before the use of spinal instrumentation, most paraplegic patients died as a result of large bedsores and urinary tract infections. Poor nonoperative treatment results and a host of complications, including gross angulation of the spine, stiffness of joints, contractures and deformities, seriously delayed or even prevented rehabilitation. Denis et al. documented a 25% incidence of late pain in patients with burst fractures treated nonsurgically (1). Internal fixation of the lumbar spine was first described in 1897 when Wilkins reported tying a carbolized silver suture around the pedicles of the T12 and L1 vertebrae in an infant who was born with a fracture dislocation (2). Early fixation devices, including Weiss springs, the Wilson plate, wire loops, and the Meurig-Williams plate, did not allow early mobilization due to inadequate fixation resulting from metal failure, wire cut-out, or bone fracture (3-6) (Fig. 1).
