Spine-shortening osteotomy for patients with tethered cord syndrome: a systematic review and meta-analysis

Purpose: Tethered cord syndrome (TCS) is the clinical manifestation of an abnormal stretch on the spinal cord, caused by several pathological conditions. Tethered cord release is the gold standard treatment for TCS. However, direct untethering carries potential risks of spinal cord injury, post-operative retethering, and CSF-related complications. Spine-shortening osteotomy (SSO) has recently been performed as an alternative technique to avoid these risks. We aimed to systematically review the literature on indications and outcome of SSO in TCS patients. Methods: We searched PubMed, Embase, Google Scholar, and the Cochrane Library to identify all studies on SSO in TCS patients. We used random or fixed-effects models to calculate rates and 95% confidence intervals to establish the rates of clinical improvement in TCS patients performed with SSO. Sensitive analysis and metaregression were made to explore potential sources of heterogeneit. Results: We identified six eligible surveys with a total population of 57. Rates ranged from 62 to 88% for neurological deficits improvement, 80-100% for motor function improvement, 60-96% for pain or numbness scores improvement, 13-67% for sensory function improvement, and 79-100% for urinary and bowel dysfunction improvement. We noted substantial heterogeneity in rate estimates for motor function and urinary and bowel dysfunction improvement (all Cochran's chi(2) significant at P<0.001; I-2=78.11%, 95%CI 61-94%; 84.28%, 18-100%; respectively). Conclusion: SSO is a safe and effective technique for TCS patients, especially in more challenging cases, such as complex malformations or revision surgery. However, future cohort studies and randomized studies with large numbers and the power to provide illumination for the surgical decision-making of TCS are warranted.