Minor Trauma Caused High-Grade Lumbosacral Spondylolisthesis After Short-Segment Lumbar Fusion: A Case Report.

CASE: Ten days after L3-L5 instrumented posterior lumbar spinal fusion, an 85-year-old woman developed Grade 4 spondylolisthesis at L5-S1 after a minor fall. She underwent posterior open reduction and internal fixation with extension of fusion from L2 to the pelvis. The preexisting hardware at L5 caused partial laceration of the right L5 nerve root. One year after surgery, computed tomography demonstrated maintenance of correction and fusion at L5-S1. CONCLUSION: High-grade lumbosacral spondylolisthesis can occur with minor trauma after short-segment lumbar fusion. Maintenance of correction and fusion is achievable with posterior open reduction and internal fixation to the pelvis alone. Preexisting hardware can damage nerve roots causing permanent neurological deficits.

Abdominal wall paresis as a complication of minimally invasive lateral transpsoas interbody fusion.

OBJECT: The minimally invasive lateral transpsoas approach for interbody fusion has been increasingly employed to treat various spinal pathological entities. Gaining access to the retroperitoneal space and traversing the abdominal wall poses a risk of injury to the major nervous structures. Nerve injury of the abdominal wall can potentially lead to paresis of the abdominal musculature and bulging of the abdominal wall. Abdominal wall nerve injury resulting from the minimally invasive lateral retroperitoneal transpsoas approach has not been previously reported. The authors describe a case series of patients presenting with paresis and bulging of the abdominal wall after undergoing a minimally invasive lateral retroperitoneal approach. METHODS: The authors retrospectively reviewed all patients who underwent a minimally invasive lateral transpsoas approach for interbody fusion and in whom development of abdominal paresis developed; the patients were treated at 4 institutions between 2006 and 2010. All data were recorded including demographics, diagnosis, operative procedure, positioning, hospital course, follow-up, and complications. The onset, as well as resolution of the abdominal paresis, was reviewed. RESULTS: The authors identified 10 consecutive patients in whom abdominal paresis developed after minimally invasive lateral transpsoas spine surgery out of a total of 568 patients. Twenty-nine interbody levels were fused (range 1-4 levels/patient). There were 4 men and 6 women whose mean age was 54.1 years (range 37-66 years). All patients presented with abdominal paresis 2-6 weeks postoperatively. In 8 of the 10 patients, abdominal wall paresis had resolved by the 6-month follow-up visit. Two patients only had 1 and 4 months of follow-up. No long-term sequelae were identified. CONCLUSIONS: Abdominal wall paresis is a rare but known potential complication of abdominal surgery. The authors report the first case series associated with the minimally invasive lateral transpsoas approach.