Anterior Column Release for Adult Lumbar Scoliosis

Abstract

Sagittal malalignment decreases patients’ quality of life and requires surgical correction to achieve realignment goals and spinopelvic balance. High-risk posterior-based osteotomy techniques ranging from posterior column osteotomies (PCO) to vertebral column resection (VCR) are the current standard treatment methods for addressing sagittal imbalance. More recently, minimally invasive surgeries (MIS) including lateral interbody fusion (LIF) have been developed in an effort to minimize the complication rate of more conventional posterior-based techniques while maintaining surgical goals. Anterior column realignment (ACR) utilizes hyperlordotic cages (20°–30°) filled with bone graft in the intervertebral disk space through an anterior lumbar interbody fusion (ALIF) retroperitoneal approach or lateral lumbar interbody fusion (LLIF) transpsoas approach. The anterior longitudinal ligament (ALL) along with the anterior annulus plays a major role in limiting the amount of distraction that can be achieved through the intervertebral disk. Hence, ALL release with careful consideration of anterior anatomic structures is required. Upon cage insertion, the construct can be secured in place with one or two screws into the adjacent vertebral bodies. It is highly recommended to perform this technique with triggered electromyogram (EMG), and somatosensory evoked potential (SSEP)/motor evoked potential (MEP) monitoring to avoid neurological complications. As a safeguard in case of vascular complications, it is prudent to have vascular surgeons available in the hospital at the time of surgery.