P98. What drives disability in cervical deformity: novel patient generated outcome versus legacy HRQL

Abstract

BACKGROUND CONTEXT Existing health outcome (HRQL) metrics do not adequately capture disability from cervical deformity (CD) and do not correlate with cervical malalignment. In the novel Patient Generated Index (PGI) patients report their greatest difficulties related to their CD. These results were used to determine items that should be included in a CD-specific HRQL. PURPOSE To utilize the PGI to reveal the aspects of CD disability not captured by existing HRQLs. STUDY DESIGN/SETTING Retrospective review of a prospective CD database. PATIENT SAMPLE A total of 45 CD patients. OUTCOME MEASURES HRQL metrics: PGI, NDI, mJOA, EQ-5D. METHODS CD patients completed the PGI by describing aspects of their disability that bother them the most. The responses were weighted and scored. PGI responses were categorized into domains: Sagittal discomfort/range of motion (ROM), Activities of Daily Living (ADL), and Social Life/Hobbies. PGI scores and legacy HRQL metrics were correlated with alignment, pain, age, sex, BMI, and medical comorbidities. R2 values are reported for linear regression models that include the drivers significantly associated with each HRQL metric. RESULTS Forty-five CD patients (mean cSVA: 51mm) including 12 PGI patients (mean cSVA: 62mm) were included for analysis. PGI scores were found to be driven significantly by age and C2 Slope (r2=0.50). NDI was driven significantly by neck pain, back pain, and BMI (r2=0.32). mJOA was driven significantly by Charlson Comorbidity Score, back pain and weight (r2=0.33). EQ5D was significantly driven by CBVA, age and T1 Slope (r2=0.78). When examining PGI domains, Sagittal Discomfort/ROM score was driven significantly by cSVA and age (r2=0.54). ADL score was driven by CBVA and a medical history of neuromuscular disease (r2=0.87). Social Life/Hobbies score was driven by Charlson Comorbidity Scores, a medical history of ankylosing spondylitis, and a medical history of connective tissue disease (r2=1.0). Horizontal Gaze/Walking Safety, Pain, and Neurologic Complaints did not correlate significantly with alignment, pain, demographic info or past medical history. CONCLUSIONS Legacy HRQLs do not adequately capture CD disability and do not correlate with cervical malalignment. In a CD cohort, PGI scores and EQ5D scores were driven significantly by sagittal alignment. However, mJOA and NDI were driven by pain and medical comorbidities. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.