Spinal Multimorbidity, Sex-Associated Disability, and Consultation Patterns in Octogenarians and Nonagenarians: A 30-Year Single-Center Retrospective Study

Purpose: To characterize baseline spinal multimorbidity, we investigated sex-associated differences in disability, and the temporal distribution of patients aged 80 years or older presenting to a tertiary spine center over three decades. Methods: We performed a retrospective single-center study (1994–2024). Of 3199 screened unique patient medical records evaluated for low back pain, 193 unique patients were age-eligible; 71 were excluded for prespecified record-quality criteria, leaving 122 patients in the analytical cohort. Baseline Visual Analog Scale (VAS) scores were available for all 122 patients and Oswestry Disability Index (ODI) scores for 99. Diagnoses required clinical-imaging concordance. A Lumbar Pathology Count (LPC) summarized seven coexisting degenerative diagnosis categories. Temporal distributions across study periods (D1: 1994–2004, D2: 2005–2014, D3: 2015–2024) were examined descriptively. Multivariable robust linear regression evaluated the association between sex and ODI. Results: Mean age was 84.2 years, and median VAS was 8/10. Among 99 patients with ODI data, mean ODI was 47.6%. Women with complete sex and ODI data had higher disability than men (51.5% vs. 39.8%; p = 0.002; Cohen d = 0.66). In the adjusted model (n = 98), female sex remained associated with a 12.3-point higher ODI (95% CI 4.5–20.2; p = 0.002). Most patients (76.2%) had more than one lumbar diagnosis (mean LPC, 1.99), but LPC was not significantly correlated with VAS or ODI. From D2 to D3, facet arthrosis increased from 31.3% to 65.3% and central disc herniation decreased from 37.5% to 9.9%; both remained significant after Benjamini–Hochberg correction (q = 0.039). The analytical cohort comprised five patients in D1, 16 in D2, and 101 in D3. Conclusions: In this selected referral-center cohort, advanced-age patients presented with severe baseline pain, disability, and frequent coexisting lumbar degeneration. Female sex was independently associated with higher baseline disability. Temporal patient distributions reflect complete-record inclusion criteria rather than population epidemiology. These findings emphasize the necessity of explicit functional phenotyping in late-life spine care.