Clinical Characterization of Hip Subgroups in Geriatric Chronic Low Back Pain.

OBJECTIVE

To investigate and compare the clinical profiles of 3 previously established hip-based subgroups of older adults with chronic low back pain (LBP) using data from multiple domains.

DESIGN

Cross-sectional analysis of baseline cohort study data.

SETTING

Clinical research laboratory.

PARTICIPANTS

Two hundred fifty (n=250) community dwelling older adults with chronic LBP.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Clinical profiles of the previously derived subgroups were established. Pain quality and dispersion were captured with the McGill Pain Questionnaire. Self-efficacy was measured using the Low Back Activity Confidence Scale. Catastrophic thoughts about LBP were captured with the Pain Catastrophizing Scale. Trunk mobility was measured with an inclinometer. Trunk muscle function was captured through standardized muscle endurance testing and ultrasound measures of muscle activity. One-way analysis of variance was used to analyze between-group differences.

RESULTS

Each chronic LBP subgroup was named based on the level of hip strength and hip symptoms: weak and symptomatic, weak and nonsymptomatic, and strong and nonsymptomatic. The weak and symptomatic subgroup had distinctly worse levels of pain quality, dispersion, catastrophizing and self-efficacy, compared with the other 2 subgroups. In contrast, the strong and nonsymptomatic subgroup, as compared with the other subgroups, had greater thoracolumbar flexion, greater trunk muscle endurance and better psychological profiles.

CONCLUSIONS

The unique clinical profile of each subgroup underscores how important it is to consider the heterogeneous nature of chronic LBP in the geriatric population when developing treatment approaches. The clinical characterization of these subgroups across multiple rehabilitation-focused domains may optimize the development of tailored interventions for each subgroup.