Epidural steroid injections may be associated with reduced bone mineral density and an increased risk for vertebral fracture, according to a systematic review published in Pain Medicine.
In this systematic review and critical literature appraisal, researchers evaluated 8 studies (n=7233) that reported on the effects of epidural steroid injections on bone mineral density, osteoporosis, vertebral fracture, or osteopenia.
Studies were required to have a control group or baseline comparisons. All epidural steroid injection dosages were converted to methyl-prednisolone equivalents, and low bone mineral density was defined by the presence of osteopenia or osteoporosis, evaluated using the World Health Organization-2 criteria (6 studies) or the International Society of Clinical Densitometry criteria (1 study).
Of the 8 studies evaluated, 5 focused on postmenopausal women only, and 3 included men and women of any age. The follow-up ranged from 6 to 60 months, and the steroids used included triamcinolone, dexamethasone, methyl-prednisolone, and betamethasone, with doses ranging from 10 to 120 mg. The mean number of injections across all studies was 14.7. The mean cumulative injection dose in methyl-prednisolone equivalents ranged from 80 to 8130 mg.
Across all studies, mean changes in bone mineral density ranged from 0.06% to 1.25% in the lumbar spine and from −2.87% to 0.45% in the femoral neck. Among patients who received epidural steroid injections, low bone mineral density was reported by 52.5% to 96.2% of patients in the lumbar spine and by 29% to 93.5% of patients in the femoral neck.
In postmenopausal women, cumulative doses of triamcinolone >200 mg during a 1-year period or >400 mg during a 3-year period were associated with reduced bone mineral density. In 1 study, each additional epidural steroid injection was shown to increase the risk for fracture (relative risk, 1.21; 95% CI, 1.08-1.30).
The study authors concluded that “[Epidural steroid injections] seem to decrease [bone mineral density], both locally (lumbar spine) and systemically (femoral neck) in doses as low as 80 mg of [methyl-prednisolone] equivalents and to increase the risk of vertebral fracture.”
Kerezoudis P, Rinaldo L, Alvi MA, et al. The effect of epidural steroid injections on bone mineral density and vertebral fracture risk: A systematic review and critical appraisal of current literature [published online January 2, 2018]. Pain Med. doi: 10.1093/pm/pnx324