Joint hypermobility may not be associated with chronic low back pain (cLBP) or lumbar osteoarthritis (OA), according to a study published in BMC Musculoskeletal Disorders.
Millions of people report pain and disability secondary to cLBP, which costs billions in lost productivity and healthcare expenditure. A link has been proposed between joint hypermobility — a modifiable risk factor — and cLBP/lumbar spinal degeneration, but few studies have examined the connection between these phenomena.
A cross-sectional analysis was performed to assess associations between hypermobility and cLBP as well as lumbar spine OA and facet joint OA, using data from 5072 patients who participated in 3 trials: the Generalized OA Study (n=1798; mean age, 69.3 years; 71.8% women), the Genetics of Generalized OA Study (n=1363; mean age, 66.0 years; 78.4% women), and the Johnston County OA Project (n=1911; mean age, 66.5 years; 64.5% women). Joint hypermobility was defined by a Beighton Score ≥4 (range 0-9), and the trunk flexion maneuver from the Beighton Score was also evaluated. Correlations between hypermobility and cLBP and lumbar OA were assessed with logistic regressions analyses.
The prevalence of LBP was 37.9% in the Generalized OA Study, 65.1% in the Genetics of Generalized OA Study, and 40.1% in the Johnston County OA Project, with corresponding Beighton scores ≥4 in 11.0%, 4.2%, and 6.4% of patients, respectively, and 12.9%, 6.9%, and 5.4% of patients, respectively who were able to perform the trunk flexion maneuver. On radiographs, 57.8%, 58.0%, and 59.5%, respectively had spine OA, and 74.1%, 66.3%, and 68.3% of patients had facet joint OA, respectively. Symptomatically, the same rates were 24.8%, 40.8%, and 24.8% for spine OA, and 28.8%, 43.9%, and 27.3% for facet joint OA, respectively.
There was a significant association in univariate models between hypermobility and symptomatic facet joint OA (pooled odds ratio [pOR], 0.64; 95% CI, 0.44-0.93), but not in multivariate models. Multivariate adjusted models did not show a significant association between hypermobility and either cLBP or lumbar OA. However, there was a significant inverse relationship between trunk flexion and cLBP (pOR, 0.40; 95% CI, 0.26-0.62), symptomatic facet joint OA (pOR, 0.53; 95% CI, 0.37-0.77), spine OA (pOR, 0.66; 95% CI, 0.50-0.87), and symptomatic spine OA (pOR, 0.39; 95% CI, 0.28-0.53). There was moderate to high between-study heterogeneity.
Study limitations include a cross-sectional design that precluded causal inference, high heterogeneity possibly secondary to different study samples and designs, and possible residual confounding.
“Hypermobility was not associated with cLBP or lumbar OA. The inverse association of trunk flexion with cLBP and lumbar OA may indicate a role for a flexible spine in avoiding or managing these conditions,” noted the authors. They recommended that future research explore the role of flexibility in prevention and/or management of spinal degeneration in younger patients in longitudinal trials designed to elucidate causative mechanisms.
Goode AP, Cleveland RJ, Schwartz TA, et al. Relationship of joint hypermobility with low back pain and lumbar spine osteoarthritis. BMC Musculoskelet Disord. 2019;20(1):158.