Nonoperative Treatment of Adult Spinal Deformity: A Comprehensive Narrative Review

Background/Objectives: Adult spinal deformity (ASD) is increasingly prevalent due to an ageing population and is associated with significant pain, disability, and reduced quality of life. While surgery is often considered for severe deformities, many patients are either unsuitable for major corrective procedures or prefer conservative care. This narrative review synthesizes the current evidence on nonoperative management strategies for ASD. Methods: A literature search on the PubMed and Cochrane databases identified relevant studies published up to 25 October 2025. Medical Subject Headings and keywords related to nonsurgical ASD management were used. Eligible studies included nonsurgical series with a minimum of 12 months' follow-up, while case reports were excluded. Results: Seven studies met our inclusion criteria: three on bracing, three on physiotherapy and combined physical and cognitive rehabilitation programmes, and one on transforaminal epidural steroid injections (ESIs). Bracing was effective in slowing the curve progression rate. One study showed that the progression rate decreased from 1.47°/year to 0.24° for degenerative scoliosis (p < 0.0001) and from 0.70°/year to 0.24° for idiopathic scoliosis (p = 0.03). Another study showed that there was no statistically significant difference in the Cobb angle or anticipated worsening when comparing the initial measurement with the final control after treatment (p = 0.973). Finally, a third study reported reduced back pain, with Roland-Morris scores improving from 3.3 to 2.0 (p < 0.001) at 18 months. Physiotherapy and multidisciplinary rehabilitation programmes appeared to be effective in significantly reducing pain and disability levels. One study found that Oswestry Disability Index (ODI) scores improved from 39.5 to 31.8 (p < 0.001), while back pain, measured using the Numeric Pain Rating Scale (NPRS), improved from 58.4 to 42.1 (p < 0.001), with 51% achieving minimal clinically important change (MCIC). Another study reported ODI reductions from 38 to 17.6 and pain scores from 6.5 to 2.2 (p < 0.001), while in a third study, the "Koshimagari Exercise" programme yielded MCIDs in the ODI for 42% of patients. Finally, ESIs provided significant pain relief for at least a month in over half of the patients with degenerative scoliosis and radiculopathy, with diminishing effects throughout the first 2 years. More specifically, 37.2% of patients had a successful outcome at one year post-injection and 27.3% at 2 years (p < 0.01). Conclusions: Our study suggests that bracing, physiotherapy, and multidisciplinary rehabilitation programmes, as well as ESIs, can serve as effective short term alternatives for patients with ASD who are either unsuitable for surgery or do not wish to pursue it. As such, this review provides valuable evidence-based insights that can guide clinicians in developing a treatment plan and lay the foundations for establishing a novel pathway for this specific subgroup of patients with ASD.