Harrington instrumentation with spinous process wiring for idiopathic scoliosis.

To provide the stability of segmental spinal instrumentation without the risk associated with the passing of sublaminar wires, a technique of SSI was developed that uses the base of the spinous process as a site for purchase. To provide a broad attachment to the spinous process, a button-wire implant was developed. The rods used are a Harrington distraction rod for the concave side of the curve and a Luque rod for the convexity. Both are attached to the spine at each level by the button-wire implant. Biomechanical testing confirms that the implant provides load sharing, an advantage over wire alone, and that the instrumented spine is stable when compared with other systems. Clinical review showed approximately 60 per cent correction of the average curve, a small correction loss, and a better sagittal alignment than achieved previously with Harrington distraction alone. Complications were few.