Monday, 25 August 2014

Piriformis Syndrome and Tethering and the Role of Exercise Physiology


Piriformis syndrome (PS) can best be described as sciatica caused from compression of the sciatic nerve by the piriformis muscle [1]. Tethering of the sciatic nerve may also occur around the tendon of the piriformis muscle (PM) which can also cause irritation. Due to the close proximity of the two structures, an inflamed or spastic PM will cause irritation to the sciatic nerve.
Piriformis syndrome can be identified by 5 salient characteristics; 1) a history of local trauma; 2) pain localised to the sacroiliac joint, greater sciatic notch, and piriformis muscle, which extends along the course of the sciatic nerve and presents difficulty when walking; 3) acute pain brought on by stooping or lifting and somewhat relieved by traction; 4) Palpable spindle mass at the location of the piriformis muscle; 5) a positive Lasegue’s sign [2]. Although difficult to substantiate, the incidence of piriformis syndrome is estimated at about 6-8% of low back pain[2]. 

Diagnosis and Examination 

Although PS only has a low occurrence amongst low back pain mechanisms, it is often underdiagnosed and mistaken for more common conditions such as facet arthropathy, sacroiliitis, lumbar disk disease, or radiculopathy [3]. Therefore, diagnosis of the disease is usually performed by a method of exclusion. A clinician will shoulder initially eliminate a aforementioned mistaken courses of pain, before proceeding to history and physical examinations.

A patient will need to provide a history, detailing sites of pain occurrence, actions which aggravate pain, and actions which may elevate pain. Some common symptoms of PS are pain in buttock with radiation down the posterior thigh, aggravation through sitting or walking [3].

These questions may be asked by a general practitioner, exercise physiologist, physiotherapist, or other clinicians involved in the diagnostic process.

This process will be followed by a physical examination which is commonly performed by a physiotherapist or exercise physiologist. Palpation of the greater sciatic notch may cause tenderness to the site, or radiation down the leg with trigger pointing of the piriformis muscle. The clinician may perform manoeuvres such as the Freiberg’s manoeuvre (see figure 2) or the Pace manoeuvre (see figure 3). A patient may also be referred for further investigation by MRI, CT, ultrasound or EMG as a method of excluding other conditions rather than an official diagnosis.

Exercise Therapy as Treatment 


Piriformis syndrome is a disorder which can be managed or reversed if addressed correctly by using methods which are often individualised depending on the underlying mechanisms which caused the initial syndrome. This process often involves an accredited exercise physiologist (AEP) whose role is to work as a part of a team to determine the underlying mechanisms and facilitate their improvement to reduce the disorders symptoms.

An exercise physiologist’s primary focus is the development of an individualised exercise program to retrain movement patterns to incorporate the correct musculature to facilitate the movement, strengthen the skeletal muscle to improve functional capacity of specific movements, and reduce symptoms of piriformis syndrome by means of trigger pointing or passive assisted stretching.

An outline program commonly encountered in the improvement of piriformis syndrome include exercises to strengthen the hip abductors, extensors, and external rotators, as well as movement re-education to activate appropriate musculature to cause the movement [3]. A program may be broken into phases to appropriately progress individuals through simple isolated movements to final stage dynamic movement patterns. This ensures the individual gains a thorough understanding of muscle activation and the difference between correct and incorrect anatomical positioning.

An example of a program outline may include: phase 1) isolated muscle recruitment exercises such as side lying clams or bilateral bridges; phase 2) weight bearing strengthening exercises, beginning with bilateral movement and progressing into unilateral movements, with exercises including bilateral air squat progressed into single leg sit backs; phase 3) functional training exercises forward and lateral lunges, and bilateral and unilateral squat jumps.

A patient progresses through the phases when the practicing exercise physiologist deems appropriate joint stability and muscle recruitment is occurring [3]. This transition should only proceed if an individual also understands or can ‘feel’ the difference in appropriate and inappropriate muscle recruitment. It is the role of an exercise physiologist to also regress exercises if needed, to allow the individual to gain a thorough understanding of movement patterns.

During the rehabilitation process an exercise physiologist will be tracking a range of different factors which may be affected by your current disorder. These may include ability to perform activities of daily living, psychosocial status, pain levels, or even sleeping patterns. These measures play an important role in the management of an individual’s quality of life (QoL) while suffering from piriformis syndrome. If a exercise physiologist can recognise factors which may be affecting an individual’s QoL, they can implement interventions to combat the said factor, or refer onto an appropriate allied health professional for further treatment.

How do you see an Accredited Exercise Physiologist 


Individuals may be referred to an exercise physiologists by their GP or other allied health practitioners, or book an appointment themselves. If referred patients may be eligible for a medicare rebate. Individuals who have private health insurance may also be able to claim rebates. To find a local AEP or find out more information about an AEP’s role, visit the Exercise and Sport Science Australia (ESSA) website at http://www.essa.org.au/

Reference List

Fishman, L. M., Dombi, G. W., Michaelsen, C., Ringel, S., Rozburch, J., Rosner, B., et al. (2002). Piriformis Syndrome: Diagnosis, Treatment, and Outcome - a 10-Year Study. Archives of Physical Medicine Rehabilitation , 83, 295-301.

Tonley, J. C., Yun, S. M., Kochevar, R. J., Dye, J. A., Farrokhi, S., & Powers, C. M. (2010). Treatment of an Individual With Piriformis Syndrome Focusing on Hip Muscle Strengthening and Movement Reeducation: A Case Report. Journal of Orthopaedic & Sports Physical Therapy , 40 (2), 103-111.

Wetchateng, T. (2013). Piriformis syndrome: Does it bother your daily life? Thammast Medical Journal , 13 (2), 237-242.

Written by Exercise Physiology Brisbane Prac Student: Riley Gould (Charles Sturt Universty).