Function-Specific Profiles of Chronic Low Back Pain in Middle-Aged and Older Patients and Their Association with...

Background/Objectives: Chronic low back pain (LBP) in older adults is usually quantified as a single global score, which may not reflect the activities in which pain actually limits the patient. This study described function-specific LBP profiles in middle-aged and older patients and examined their cross-sectional association with standing sagittal spinopelvic alignment. Methods: This cross-sectional, retrospective observational study evaluated 102 patients with chronic LBP, categorized into Group M (under 75 years; n = 51) and Group O (75 years or older; n = 51). Visual Analog Scale (VAS) scores were assessed during rest, getting up, rolling over, and walking (gait). An exploratory index, the proportional pain contribution (VAS%), was derived by expressing each phase as a percentage of the sum of the four scores; because the four values sum to 100% by definition, VAS% was interpreted only as a descriptor of the within-patient distribution of pain and always alongside the absolute scores. Lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), sacral slope and PI minus LL (PI-LL) were measured on standing radiographs. Results: Group M reported higher absolute pain than Group O at rest, on getting up and on rolling over (all p < 0.001), whereas absolute gait pain did not differ between the groups (p = 0.730). As a consequence of this pattern, Gait VAS% was higher in Group O (median 59.8% vs. 27.3%, p < 0.001). Group O had lower LL (p = 0.001) and a larger PI-LL (p = 0.005); PI and PT did not differ significantly. Gait VAS% correlated with age (τ = 0.33) and PI-LL (τ = 0.29). In exploratory multivariable models, age and PI-LL were retained in the final model for Gait VAS% and were independently associated with it (β = 0.37 and 0.30 respectively; R² = 0.29). Conclusions: In this sample, the older patients reported less pain at rest and during postural transitions but similar pain during walking, so that walking accounted for a larger share of their total reported pain burden. This proportional pattern was associated with a larger standing PI-LL mismatch, although the association was modest. The findings are descriptive and hypothesis-generating, and suggest that asking separately about pain during walking may add information that a single global score does not capture.