Ultrasound appears to be a reliable technique for the diagnosis of piriformis syndrome

Abstract

Introduction : Piriformis muscle syndrome (PS) is a disorder encompassing a constellation of symptoms, including buttock and hip pain. In this study we aimed to assess the value of ultrasound (US) in the diagnosis of PS. Methods : Thirty‐three clinically diagnosed PS patients and 26 healthy volunteers underwent a clinical PS scoring examination and US and MRI assessment of the bilateral piriformis muscles. The areas under the receiver operating characteristic curves (AUROCs) of the US parameters (i.e., increased thickness [iTh] and increased cross‐sectional area [iCSA]) for piriformis muscle were evaluated. Results : On US and MRI, the thickness and CSA were increased in PS patients. The AUROCs for the iTh and iCSA for discriminating stage 0 (healthy volunteers) from stage 1 through stage 3 (PS patients) were 0.88 and 0.95, respectively. Discussion : US may be a reliable technique for the clinical diagnosis of PS. Muscle Nerve 59:411–416, 2019

Piriformis syndrome – a diagnosis comes into its own

“…The article of Zhang et al in this issue provides evidence for the reliability of ultrasound in the diagnosis of piriformis syndrome, and thus may be of value in the assessment of many patients with sciatica. Some researchers have suggested that piriformis syndrome (PS) is at least as common a cause of sciatica as is disc herniation .…”

“…Conversely, negative findings on these methods provide powerful evidence against PS. (1) Ultrasound (US) appears to provide an inexpensive and accurate diagnosis available to a large population. (2) Magnetic resonance neurography (MRN) delineates the sciatic nerve, the piriformis muscle, and a good deal of surrounding anatomy .…”

“…US and MRN reflect Robinson's “sausage‐like excrescences” by directly visualizing an abnormally thick structure, concordant with the functional symptomatology seen in the FAIR‐test's extension of the physical exam, and the physical exam itself. In this model medical science focuses first on the physical examination, then on the functional ramifications of the pathology that the physical examination detected, then back to a more sensitive assessment of the physical abnormality responsible for it …”

“…In this model medical science focuses first on the physical examination, 13,14 then on the functional ramifications of the pathology that the physical examination detected, 6 then back to a more sensitive assessment of the physical abnormality responsible for it. 1 Future studies should assess the utility of the US technique of Zhang et al for evaluation of other compression neuropathies such as thoracic outlet syndrome, pronator syndrome, and radial nerve entrapment at the arcade of Frohse. Ethical Publication Statement: We confirm that we have read the Journal's position on issues involved in ethical publication and affirm that this report is consistent with those guidelines.…”

Clinico-radiological review of peripheral entrapment neuropathies – Part 2 Lower limb

“…Piriformis syndrome is a controversial entity, postulated to cause sciatic nerve compression due to asymmetric hypertrophy or variant anatomy. MRI or US finding of asymmetric piriformis muscle hypertrophy in addition to clinical symptoms is needed to diagnose this entity since asymmetric hypertrophy of piriformis can also be a normal variant [20][21][22]. The affected sciatic nerve may also show thickening on MRI/US and signal alteration on MRI.…”