Adult Cervical Deformity Patients Have Higher Baseline Frailty, Disability, and Comorbidities Compared With Complex Adult Thoracolumbar Deformity Patients: A Comparative Cohort Study of 616 Patients

Study Design: Multicenter comparative cohort. Objective: Studies have shown markedly higher rates of complications and all-cause mortality following surgery for adult cervical deformity (ACD) compared with adult thoracolumbar deformity (ATLD), though the reasons for these differences remain unclear. Our objectives were to compare baseline frailty, disability, and comorbidities between ACD and complex ATLD patients undergoing surgery. Methods: Two multicenter prospective adult spinal deformity registries were queried, one ATLD and one ACD. Baseline clinical and frailty measures were compared between the cohorts. Results: 616 patients were identified (107 ACD and 509 ATLD). These groups had similar mean age (64.6 vs 60.8 years, respectively, P =.07). ACD patients were less likely to be women (51.9% vs 69.5%, P <.001) and had greater Charlson Comorbidity Index (1.5 vs.9, P <.001) and ASA grade (2.7 vs 2.4, P <.001). ACD patients had worse VR-12 Physical Component Score (PCS, 25.7 vs 29.9, P <.001) and PROMIS Physical Function Score (33.3 vs 35.3, P =.031). All frailty measures were significantly worse for ACD patients, including hand dynamometer (44.6 vs 55.6 lbs, P <.001), CSHA Clinical Frailty Score (CFS, 4.0 vs 3.2, P <.001), and Edmonton Frailty Scale (EFS, 5.15 vs 3.21, P <.001). Greater proportions of ACD patients were frail (22.9% vs 5.7%) or vulnerable (15.6% vs 10.9%) based on EFS (P <.001). Conclusions: Compared with ATLD patients, ACD patients had worse baseline characteristics on all measures assessed (comorbidities/disability/frailty). These differences may help account for greater risk of complications and all-cause mortality previously observed in ACD patients and facilitate strategies for better preoperative optimization.