Development of a Hierarchical Approach to SRS-Schwab Modifier Realignment in ASD Surgery — The International Society for the Study of the Lumbar Spine
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  2. Special Poster Session 2F. ARTIFICIAL INTELLIGENCE AND NOVEL TECHNOLOGIES
  3. Development of a Hierarchical Approach to SRS-Schwab Modifier Realignment in ASD Surgery

Development of a Hierarchical Approach to SRS-Schwab Modifier Realignment in ASD Surgery (#125)

Peter G Passias 1 , Tyler K Williamson 1 , Rachel Joujon-Roche 1 , Bailey Imbo 1 , Peter Tretiakov 1 , Oscar Krol 1 , Kevin Moattari 1 , Stephane Owusu-Sarpong 1 , Jordan Lebovic 1 , Shaleen Vira 2 , Bassel Diebo 3 , Paul Park 4 , Dean Chou 5 , Praveen Mummaneni 5 , Saman Shabani 5 , Virginie Lafage 6 , Renaud Lafage 6 , Burhan Janjua 7
  1. Department of Orthopaedic Surgery, NYU Langone, New York, NY, United States
  2. UT Southwestern, Dallas
  3. SUNY Downstate, New York
  4. Department of Neurologic Surgery, University of Michigan, Ann Arbor, Michigan, USA
  5. Department of Neurological Surgery, University of California San Francisco, San Francisco, California, USA
  6. Department of Orthopaedics, Lenox Hill Hospital, Northwell Health, New York, NY, USA
  7. Department of Neurotrauma, Neuro-oncology, and Spine , Mercy Health , Chicago, IL, USA

619336f55191e-Capture.PNG619336f55191e-Capture3.JPG619336f55191e-CaptureTable5.JPG619336f55191e-Capture4.JPGIntroduction: Patient-reported outcome measures have become ubiquitous for assessing improvement after corrective spine surgery. There remains a paucity of literature regarding the order of addressing SRS-Schwab modifiers during corrective surgery for ASD.

Objective: To investigate which SRS-Schwab modifier-combinations, if any, produce better 1-year HRQL metrics and decrease the risk of junctional failure when realigned. Secondly, to determine a hierarchical approach to modifier realignment during ASD surgery.

 

Study Design/Setting: Retrospective cohort study of a prospective adult spinal deformity (ASD) database.

 

Methods: Descriptive analysis identified cohort demographics, radiographic parameters, and surgical details. Significant differences in outcomes between patients who achieved age-aligned match in SRS-Schwab criteria and those with deformities at 1 years (1Y) were isolated. Multivariate analysis controlling for baseline disability assessed which SRS-Schwab criteria had the greatest impact on outcomes and the patients matching in that parameter were isolated. The following parameters were assessed for differences in complication rates and meeting MCID in either ODI or SRS-Total at one year via multivariate analysis.

 

Results:  445 ASD patients who underwent surgery were included. Patients had the following mean BL Schwab modifier measurements: SVA 64.2±72.3 cm, PI-LL 15.5±21.6 cm, PT 23.82±10.9 cm, and T4-T12 -34.2±20.3 cm. Age-aligned match SVA at one year was most significantly correlated with lower complication rates and improved outcomes when compared to being overcorrected or undercorrected. After isolating patients matching in 1Y SVA, there were no significant differences based on realignments in PT at one year in either complication rates or clinical outcomes. Similar rates of meeting MCID in either ODI or SRS-Total were seen when comparing PI-LL realignments. However, SVA-matched patients developed more PJK/PJF, minor complications, and a higher rate of reoperation when overcorrected in PI-LL (all p<.05).

Conclusion: Correction of SVA to ideal age-adjusted values should be prioritized during ASD surgery. The analysis of correction in PI-LL or PT following realignment in SVA improves our understanding of the interplay of various radiographic parameters and enables spine surgeons to provide more tailored corrections based on the presentation of ASD patients.

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