Evolution of Sagittal Imbalance Following Corrective Surgery for Sagittal Plane Deformity

Neurosurgery 81:129–134, 2017

Sagittal balance in adult spinal deformity is a major predictor of quality of life. A temporary loss of paraspinalmuscle force and somatic pain following spine surgery may limit a patient’s ability to maintain posture.

OBJECTIVE: To assess the evolution of sagittal balance and clinical outcomes during recovery from adult spinal deformity surgery.

METHODS: Retrospective review of a prospective observational database identified a consecutive series of patients with sagittal vertical axis (SVA) > 40mm undergoing adult deformity surgery. Radiographic parameters and clinical outcomes were measured out to 2 yr after surgery.

RESULTS: A total of 113 consecutive patients met inclusion criteria. Mean preoperative SVA was 90.3 mm, increased to 104.6mm in the first week, then gradually reduced at each follow-up interval to 59.2mm at 6wk, 45.0mm at 3mo, 38.6mm at 6mo, and 34.1mm at 1 yr (all P < .05). SVA did not change between 1 and 2 yr. Pelvic incidence-lumbar lordosis (PI-LL) corrected immediately from 25.3◦ to 8.5◦ (16.8◦ change; P < .01) and a decreased pelvic tilt from 27.6◦ to 17.6◦ (10◦ change; P < .01). No further change was noted in PILL. Pelvic tilt increased to 20.2◦ (P = .01) at 6wk and held steady through 2 yr. Mean Visual Analog Scale, Oswestry Disability Index, and Short Form-36 scores all improved; pain rapidly improved, whereas disability measures improved as SVA improved.

CONCLUSION: Radiographic assessment of global sagittal alignment did not fully reflect surgical correction of sagittal balance until 6 months after adult deformity surgery. Sagittal balance initially worsened then steadily improved at each interval over the first year postoperatively. At 1 yr, all clinical and radiographic measures outcomes were significantly improved.

 

The evolution of thoracolumbar injury classification systems

The Spine Journal 9, Issue 9, September 2009, Pages 780-788doi:10.1016/j.spinee.2009.04.003

An ideal classification system for thoracolumbar (TL) spine fractures should facilitate communication between treating physicians and guide treatment by means of outlining the natural history of injuries. The classification scheme should also be comprehensive, intuitive, and simple to implement. At the present time, no classification system fully meets these criteria. In this review, the authors attempt to describe the evolution of TL fracture classification systems from their inception to the present day.

The article reviews the salient classification systems that have addressed TL injuries since Boehler’s first attempt in 1929. This progression culminates in the Thoracolumbar Injury Severity Score/Thoracolumbar Injury Classification and Severity Score (TLISS/TLICS), a system which incorporates features from earlier scales and represents the most comprehensive grading scale to date.

Each successive system played an important role in advancing contemporary understanding of TL injuries. Most classifications were, however, based on a single individual’s, or a comparatively small group’s, retrospective review of a case series. In most instances, these grading systems were never validated or modified by their original developers, a shortcoming that prevented their continued evolution. Despite the many advantages of the TLISS/TLICS system, more work in terms of refining the classification and defining its validity remains to be performed.

The classification of TL injuries has evolved significantly over the course of the last 75 years. Most of these schemes were limited by their complexity, relevance, and/or poor reliability. The TLISS classification system represents the most recent evolution as it combines several important factors capable of guiding the management of TL injuries. Nonetheless, more research regarding this rating scale remains to be performed.