LAUSR

Background Lumbar instability has been extensively reported; however, the risk factors for lumbar instability remain poorly defined, and understanding this condition better would help health professionals and their patients. Proposal To determine the prevalence of lumbar instability in Thai people with chronic low back pain (CLBP) and explore the factors associated with lumbar instability in these patients. Patients and Methods Using multistage random sampling methods, 1762 participants with CLBP were enrolled in the study from six regions of Thailand. Data were collected using a paper-based questionnaire. Participants were interviewed by physical therapists in the hospital they attended. They were classified as having lumbar instability when they attained ≥7/14 items on the lumbar instability screening tool. Univariate and multivariate regression analysese were used to determine the possible factors associated with lumbar instability. Results There were 961 (54.54%) participants with lumbar instability and 801 (45.46%) participants without. The eight factors associated with lumbar instability were: (i) age ≥40 years (AOR: 1.36; 95% CI: 1.09–1.69); (ii) body mass index ≥25 kg/m2 (AOR: 1.42; 95% CI: 1.16–1.74); (iii) having an underlying disease (AOR: 1.32; 95% CI: 1.06–1.65); (iv) frequent lifting ≥5 kg in occupational habits (AOR: 1.69; 95% CI: 1.36–2.09); (v) prolonged walking ≥4 hours per day (AOR: 1.31; 95% CI: 1.04–1.64); (vi) gardening in leisure time (AOR: 1.37; 95% CI: 1.10–1.71); (vii) other area of pain (AOR: 1.24; 95% CI: 1.01–2.52): and (viii) other area of numbness (AOR: 1.85; 95% CI: 1.50–2.27). When considering only women, prior pregnancy was associated with lumbar instability with OR of 1.76 (95% CI: 1.36–2.22), p-value <0.0001. Conclusion When treating patients with CLBP who are suspected to have lumbar instability, healthcare professionals should consider associated factors that might be modifiable targets for interventions to improve outcomes.