Pelvic Nonresponse Following Treatment of Adult Spinal Deformity: Influence of Realignment Strategies on Occurrence.
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2023-05
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Abstract
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Despite adequate correction, the pelvis may fail to readjust, deemed pelvic nonresponse (PNR). To assess alignment outcomes [PNR, proximal junctional kyphosis (PJK), postoperative cervical deformity (CD)] following adult spinal deformity (ASD) surgery utilizing different realignment strategies.Materials and methods
ASD patients with two-year data were included. PNR defined as undercorrected in age-adjusted pelvic tilt (PT) at six weeks and maintained at two years. Patients classified by alignment utilities: (a) improvement in Scoliosis Research Society-Schwab sagittal vertical axis, (b) matching in age-adjusted pelvic incidence-lumbar lordosis, (c) matching in Roussouly, (d) aligning Global Alignment and Proportionality (GAP) score. Multivariable regression analyses, controlling for age, baseline deformity, and surgical factors, assessed rates of PNR, PJK, and CD development following realignment.Results
A total of 686 patients met the inclusion criteria. Rates of postoperative PJK and CD were not significant in the PNR group (both P >0.15). PNR patients less often met substantial clinical benefit in Oswestry Disability Index by two years [odds ratio: 0.6 (0.4-0.98)]. Patients overcorrected in age-adjusted pelvic incidence-lumbar lordosis, matching Roussouly, or proportioned in GAP at six weeks had lower rates of PNR (all P <0.001). Incremental addition of classifications led to 0% occurrence of PNR, PJK, and CD. Stratifying by baseline PT severity, Low and moderate deformity demonstrated the least incidence of PNR (7.7%) when proportioning in GAP at six weeks, while severe PT benefited most from matching in Roussouly (all P <0.05).Conclusions
Following ASD corrective surgery, 24.9% of patients showed residual pelvic malalignment. This occurrence was often accompanied by undercorrection of lumbopelvic mismatch and less improvement of pain. However, overcorrection in any strategy incurred higher rates of PJK. We recommend surgeons identify a middle ground using one, or more, of the available classifications to inform correction goals in this regard.Level of evidence
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Passias, Peter G, Katherine E Pierce, Tyler K Williamson, Oscar Krol, Renaud Lafage, Virginie Lafage, Andrew J Schoenfeld, Themistocles S Protopsaltis, et al. (2023). Pelvic Nonresponse Following Treatment of Adult Spinal Deformity: Influence of Realignment Strategies on Occurrence. Spine, 48(9). pp. 645–652. 10.1097/brs.0000000000004464 Retrieved from https://hdl.handle.net/10161/27931.
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Peter Passias
Throughout my medical career, I have remained dedicated to improving my patients' quality of life. As a specialist in adult cervical and spinal deformity surgery, I understand the significant impact our interventions have on individuals suffering from debilitating pain and physical and mental health challenges. Spinal deformity surgery merges the complexities of spinal biomechanics with the needs of an aging population. My research focuses on spinal alignment, biomechanics, innovative surgical techniques, and health economics to ensure value-based care that enhances patient outcomes.
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