Modified Bohlman Method for High-grade Spondylolisthesis.

Abstract

High-grade lumbosacral spondylolisthesis in children often requires surgery. Goals of surgery are to resolve back or radicular pain, relieve neurologic deficit, and achieve bony fusion in order to prevent progression. Surgical options range widely from in situ uninstrumented posterolateral fusion to reduction of deformity with instrumented circumferential fusion. This article reviews our preferred method of in situ instrumented posterolateral and interbody fusion.

Key concepts: (1)The presented method modifies the Bohlman method in these salient aspects:•Using a single-strut cortical allograft and bone morphogenic protein (BMP) for interbody fusion instead of two dowels of fibular autograft to avoid donor site morbidity.•Leaving intact the posterior prominence of the first sacral vertebral body to provide cortical strength at the entry site of the strut allograft.•Adding two solid stainless steel 6.5 mm screws to back up an interbody strut allograft to lower the risk of graft fracture.(2)Advantages of this modified Bohlman method are the cost-effective implants and single-stage posterior approach.(3)Disadvantages are the lack of deformity reduction, unknown long-term effect on sagittal alignment, and patient-reported outcomes.