What is it?

Piriformis syndrome is an irritation of the piriformis muscle caused by a compression of the sciatic nerve as it passes through this muscle, which is located deep in the pelvic and buttocks region.  The sciatic nerve is the principle nerve bundle emanating from the lower lumbar and sacral vertebrae of the spine.  It passes beneath the piriformis muscle and above the smaller rotator muscles in most individuals, and through the piriformis muscle in a small percentage of others.  Lying beneath the larger gluteus maximus muscle and above several smaller hip rotator muscles, the piriformis muscle connects the sacral vertebrae to the femur (hip bone) and acts as an external rotator of the hip when contracted.

How does it occur?

When the sciatic nerve becomes irritated or inflamed due to excessive tightness, spasm, or hypertrophy (increased size) of the piriformis muscle.  Many circumstances can lead to this.  Here are some of the more common causes.   

  • Trauma:  A hard fall in the seated position can directly injure the sciatic nerve or cause secondary nerve compression due to gluteal muscle contusion and swelling.
  •  Acute piriformis muscle strain:
    *     Bending and twisting while lifting an object from the floor.
    *     Carrying heavy objects up and down stairs.
    *     Downhill running.
    *     Prolonged sitting on a hard surface or in a crossed leg position.
  •  Chronic piriformis muscle strain:

*     Bony malalignment of the lower extremities (ie: knock knees or flat 
 feet) producing excessive hip rotation with walking and running.

*     Increased lumbar spine curvature due to abdominal weakness, hip flexor
 muscle tightness, maternity, and poor posture.
*     Lumbar spine and/or sacroiliac joint pathology.
*     Prolonged driving with the seat rest back and the knees relatively
 extended.       
*     Excessive exercise training involving hip and gluteal muscles.

What are the symptoms?

  • Deep, burning pain in the buttocks or sacroiliac region- (increases with sitting, walking, climbing stairs, lifting or carrying objects, and running.)
  • Hypersensitivity, numbness, or tingling along back of thigh to bottom of foot at midstage.
  •  Muscular weakness and atrophy of hamstrings and calf with end stage progression.

How is it diagnosed?

Since your sciatic nerve begins in the spine, it can be irritated from a back injury such as a herniated disk. Your doctor will discuss how your symptoms began and any previous history of back or hip injury.  He or she will examine your back to determine if this is where the sciatic nerve is irritated and then your hip and leg to determine if movement in these areas create your symptoms.  X-rays, a Computed Tomography (CT) Scan, or a Magnetic Resonance Image (MRI) may be ordered to rule out any spine pathology or injury.  Unfortunately, there are no X-ray tests that can if the sciatic nerve is being irritated at the piriformis muscle.

How is it treated?

Immediate treatment may include:

  • Icing the affected area 15 to 20 minutes, 3 to 4 times per day.
  • Resting on your stomach or back with the hips extended.
  • Prescribed anti-inflammatory or muscle relaxant medication.
  • Avoiding postures and activities which aggravate your symptoms.  

Physical Therapy:

  • Assessment of your posture and lower extremity alignment Evaluation of the lumbar spine, hip, and lower extremity joint mobility, range of motion, flexibility, and strength.
  • Symptom provocation testing of the lumbar spine, sacroiliac joint, hip, and sciatic nerve to determine the source and extent of the injury.
  • Palpation of the trunk, pelvis, and hip soft tissue structures to determine the degree of irritability, restriction, and spasm associated with the individual's condition.
  • Gait and functional assessment.

Once the evaluation has been performed, treatment can be initiated.  Physical therapy treatment may include:

  • Therapeutic modalities such as moist heat, ice, ultrasound, and electrical stimulation help to decrease pain and spasm, yet increase blood flow and soft tissue flexibility.
  • Soft tissue mobilization or massage to increase blood flow, decrease spasm and associated soft tissue restrictions, and improve soft tissue mobility.
  • Joint mobilization to the lumbar spine, sacroiliac joint, and hip as indicated to restore normal joint mobility, range of motion, and function.
  • Manual and self stretching activities to improve trunk and lower extremity flexibility, and range of motion.
  • Postural training exercises emphasizing abdominal and hip extensor strengthening, low back and hip flexor stretching.
  • Instruction in activity and postural modification to decrease aggravation and perpetuation of symptoms with activities of daily living
  • Functional foot orthoses may be recommended to restore normal foot and lower extremity alignment.  This may help to decrease pain and mechanical stresses to the piriformis muscle, and prevent future re-injury.

When can I return to my sport or activity?

The goal of rehabilitation is to return to your sport or activity as soon as is safely possible.  If you return too soon you may worsen your condition, which could lead to permanent damage.  Everyone recovers from injury at a different rate and is determined by how fast your nerve recovers, not by the time elapsed since the onset of your injury.  In general, the longer you have symptoms before you start treatment, the longer it will take to recover.

You may safely return to your sport when:

  • You are completely pain-free.
  • You have regained full strength in the affected leg.
  • You can jog, sprint, cut, jump, and perform your daily activities on the affected leg without eliciting pain or symptoms.

How can I prevent Piriformis Syndrome?

  • Maintain good flexibility of the trunk and lower extremity musculature.
  • Maintain good strength of the abdominal and gluteal musculature.
  • Sit with your feet flat on the ground.
  • When driving, adjust the seat to keep the hips and knees comfortably bent.
  • Avoid sitting with a wallet in the back pocket.
  • Maintain good posture when sitting, standing, and lifting.
  • Lift with your legs and not your back.
  • When lifting keep objects close to your body.
  • Avoid combined twisting and lifting motions with feet planted, instead, move your feet and keep the object directly in front of your body.
  • Warm-up properly prior to starting your sport or activity.