INTRODUCTION: Prevalence estimates for sources of low back pain (LBP) sampling consecutive subjects regardless of clinical picture indicate 39% for disc (IDD), 15‐40% for facet joint arthrosis (FJA), and 13‐18% for sacroiliac joint dysfunction (SIJD). Patient age, LBP location, and exam findings implicate certain structures as the source of LBP. This study compared the prevalence estimates of IDD, FJA, and SIJD in subjects diagnosed by implementing an algorithmic approach predicated by best available evidence regarding historical and physical exam features of LBP to previously published prevalence data.
METHODS: Retrospective review of consecutive LBP patients having undergone provocation lumbar discography (PLD), diagnostic FJ or SIJ blocks according to clinical impression until a diagnosis was achieved. Midline LBP patients demonstrating centralization underwent PLD; paramidline LBP patients with 3/5 positive SIJ stress maneuvers underwent SIJ blocks; paramidline LBP patients without centralization or SIJ maneuvers underwent FJ blocks. Prevalence rates and 95% confidence intervals (CI) were computed for each diagnostic group and compared to published prevalence estimates.
RESULTS: 378 cases from 358 subjects (34.9% male) were reviewed with a mean age of 52.8 years (SD = 15.0) and median duration of LBP of 12 months (IQR = 6 to 24). 208 cases were not included in subsequent calculations because these patients did not undergo definitive diagnostic procedures. 41.8% of cases were IDD (95% CI = 34.6% to 49.3%), 30.6% FJA (95% CI = 24.2% to 37.9%), and 18.2% SIJD (95% CI = 13.2% to 24.7%). The previously reported prevalence data for each diagnostic group falls within our CI's.
DISCUSSION: Reported prevalence ranges for SIJD, IDD, and FJA are well within prevalence data collected utilizing an algorithmic approach of best available evidence for predictive value of LBP location and exam findings. Application of an evidence and/or knowledge based approach to diagnosing LBP can yield accurate diagnoses.