A Narrative Review of Symptom Severity and Duration in Nonoperative vs Operative Patients With Adult Spinal Deformity

Study DesignNarrative review.ObjectiveOur objective was to provide an evidence-based summary of how symptoms (severity/duration) impact timing of surgery for adult spinal deformity (ASD).MethodsThe authors queried PubMed, MEDLINE, and Scopus to identify potentially relevant studies. Articles were included based on quality of design, methodology, assessment of symptoms (back/leg pain, neurological deficits) and other factors which could influence timing of surgery.ResultsDatabase query produced 138 potentially relevant studies. Review of these studies and relevant references generated 29 studies that were included. Back and leg pain were the most common assessed symptoms: NRS back pain (nonoperative 4.4-5.3, operative 6.3-7.1) and NRS leg pain (nonoperative 2.3-4.1, operative 4.2-5.4). Leg pain was an independent predictor of surgery. Back/leg pain positively correlated with disability and worse health status, which were important factors driving surgery. ODI ≥40 was identified as a potential disability threshold associated with surgery. Few studies (n = 2) provided assessment of neurological deficits, and development of weakness was associated with surgery. Symptom duration was assessed using post hoc analysis of nonoperative to operative crossover (n = 6; mean time to crossover 0.8-1.1 years).ConclusionsOur results suggest at least moderate symptoms should be present prior to considering surgery. Less data exists for symptom duration and is from studies reporting nonoperative to operative treatment crossover. Future research is needed to determine clinically meaningful differences in validated outcome instruments for baseline comparisons prior to treatment, provide more detailed assessments of leg pain (radiculopathy vs claudication) and deficits, and include dynamic functional testing.