Re: Diagnosis and treatment of sciatica
In their otherwise excellent overview of sciatica, Jensen et al perpetuate the outdated notion that “Rarely, extraspinal pathology in the lumbosacral nervous plexus…can mimic symptoms of disc herniation”. As many as 49% of cases of sciatica do not have a cause on current routine MRI imaging(1) so it is time to stop thinking of sciatica as primarily a radiculopathy caused by disc degeneration or spinal canal stenosis.
Extraspinal pathology from musculoskeletal conditions is being increasingly recognised. Once termed the piriformis syndrome, they may account for many of the cases currently undiagnosed. As more musculoskeletal conditions have been found to cause sciatica, the condition is better termed the deep gluteal syndrome (2). Two cohort studies of patients with low back or sciatica have have reported a prevalence of piriformis syndrome in 6(3) and 17%(4) of patients in secondary care. These may be underestimates because of their inclusion criteria. It is time to consider the deep gluteal syndrome in the differential diagnosis of sciatica.
1. Sirvanci M, Kara B, Duran C et al. Value of Perineural Edema/Inflammation Detected by Fat Saturation Sequences in Lumbar Magnetic Resonance Imaging of Patients with Unilateral Sciatica. Acta Radiologica. 2009;50:205-211.
2. Deep gluteal syndrome: an overlooked cause of sciatica. [editorial]. Br J Gen Pract 2019;69(687):485.
3. Singh US, Meena RK, Singh CK, Singh AJ, Singh AM, Langshong R. Prevalence of piriformis syndrome among the cases of low back/buttock pain with sciatica: A prospective study. Journal of Medical Society. 2013;27:94.
4. Kean Chen C, Nizar AJ. Prevalence of Piriformis Syndrome in Chronic Low Back Pain Patients. A Clinical Diagnosis with Modified FAIR Test. Pain Practice. 2012
Competing interests: No competing interests