Journal Club
March 2014
Brought to you by the AOCPMR Student Council
Article title:
Brief review: Piriformis syndrome; etiology, diagnosis, and management
Authors:
Danilo Jankovic MD, Philip Peng MBBS, Andre van Zundert MD PhD
Journal/Source:
Can J Anesth/J Can Anesth (2013) 60:1003-10012
Discussion:
This review article focused on providing a well rounded looks at piriformis syndrome; including etiology
diagnosis and management. The principal source of data was collected using a literature search of the
MEDLINE® database from January 1980 to December 2012.
Conservative estimates of new cases of lower back pain and sciatica total 40 million annually and with
piriformis syndrome responsible for 5-6% of cases of sciatica, this topic would represent an incidence of
2.4 million per year. Many etiological factors may account for the symptoms of piriformis syndrome,
however in most patients there is no identifiable cause.
Clinical presentation is mainly divided into somatic and neuropathic components. The somatic
component is a myofascial pain syndrome, and the neuropathic component refers to the compression or
irritation of the sciatic nerve as it courses through the infrapirifom foramen.
There is no gold standard in diagnosing piriformis syndrome. The physical exam is important in revealing
well-described signs such as piriformis, Freiberg’s, Pace’s, and Lasegue’s signs. Beatty’s maneuver as well
as the Hughes test may also be positive. Electrophysiological tests serve as a means of diagnosis if the
muscle is stressed as with the FAIR test. Other diagnostic imaging modalities include CT, MRI,
scintigraphy, and ultrasound.
Piriformis syndrome typically responds to conservative treatments such as physical therapy, lifestyle
modifications, psychotherapy and pharmacological agents such as NSAIDs, muscle relaxants and
neuropathic pain medications. Surgical treatment is seldom necessary.
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Current techniques in piriformis muscle injection are offered to patients as part of a multimodal therapy.
An ultrasound-guided injection has the advantage over the CT-guided technique in that it avoids
radiation exposure, offers real-time surveillance of the injection, and is more affordable. The accuracy of
needle placement with ultrasound was validated with accuracy suggestive of 95%. Injections of local
anesthetics, steroids, and botulinum toxin into the piriformis muscle can serve both diagnostic and
therapeutic purposes. In order to optimize management of piriformis syndrome an interdisciplinary
evaluation of treatment should be utilized.
Questions:
1) Discuss the anatomical variation as well and their impact on diagnosis and treatment of piriformis
syndrome.
2) With no gold standard in diagnosis, under what circumstances and with which modality would you
evaluate someone for piriformis syndrome?
3) Discuss the role of OMM in the treatment of piriformis syndrome regarding the somatic and
neuropathic components.
Reviewer:
Gary Panagiotakis, OMS-IV, AOCPMR Student Council Education Committee
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