Piriformis Syndrome
The “sciatica” you feel could be piriformis syndrome
Get the Correct Diagnosis
Piriformis Syndrome is more pervasive than many physicians realize. For example, in the United States each year, 1.5 million people have lumbar MRI scans to look for the cause of the buttock and leg pain called "sciatica."
Yet more than 1.2 million of those scans fail to find the cause in the spine. Three hundred thousand of the scans are sufficiently positive that the patient has lumbar spine surgery. And of the 300,000 surgeries, as many as 25% fail to relieve the pain — in many cases because the diagnosis of a spinal cause for the sciatica was incorrect.
Piriformis syndrome also causes sciatica. Its treatment is much less invasive and severe than the treatment of herniated lumbar disks. However, many doctors never consider piriformis syndrome as a possible diagnosis. Many physicians who are aware of it are uncertain how to properly diagnose and treat it.
Dr. Aaron Filler credits the advent of MR Neurography and Open MR injection techniques with new large-scale outcome as leading to the successful diagnosis and treatment of many more sciatica sufferers.
Anatomy of Piriformis Muscle and Sciatic Nerve
The nerve-related leg pain of Sciatica is often due to piriformis muscle syndrome. Unlike the sciatica from a herniated disk, there is often little or no back pain while buttock pain predominates. The pain is worse when sitting, relieved by standing or walking, and often extends no farther down the leg than the ankle or mid-foot. When toes are involved, it usually affects all five toes.
Certain leg positions pull the piriformis muscle up against the sciatic nerve causing buttock pain and radiating leg pain.
Physical Exam Findings and Key Symptoms
The patient's foot is placed lateral to the contralateral knee. Resisted abduction or adduction against the examiner's hand may reproduce the symptoms. Straight leg raising is typically negative.
Relief can be obtained by traction on the involved leg, particularly by pulling upwards at a ten to twenty degree angle and towards the contralateral side. Symptoms usually involve both L5 (big toe) and S1 (small toe) components.
MR Neurography Diagnosis
Advanced MR Neurography imaging demonstrates findings observed in severe cases of piriformis syndrome when used with soft tissue MR pelvis imaging protocols.
Coronal T2-weighted neurographic images show sciatic nerve hyperintensity at the sciatic notch
Axial T1-weighted images showing asymmetry in piriformis muscle size and shape
Curved reformat images of sacral spinal nerves and lumbo-sacral plexus
T2-weighted images showing hyperintensity and loss of fascicular detail
Treatment Options
Open MRI Guided Injection
The piriformis muscle is a relatively small structure located as far as eight inches below the surface of the buttock. If a blind injection misses the muscle, the injection test is meaningless. Immediately deep to the piriformis muscle is the sciatic nerve and the colon so misplacement of the needle may lead to significant complications.
Dr. Aaron Filler's use of Open MRI image guidance makes this a safe, reliable and accurate procedure. In about 20% of cases the injection is therapeutic and the piriformis syndrome resolves completely and permanently. In others, the injection needs to repeated in a few months, and in still others, it last only a few days. In this category, surgery may be required to maintain the pain relief.
Outpatient Minimally Invasive Surgery
Piriformis surgery is now a small procedure which can be carried out under local anaesthetic as an outpatient. Traditional piriformis surgery is a large and debilitating operation but no patient should be having these operations today.
The new type of "minimal access surgery" developed at the Institute for Nerve Medicine by Dr. Aaron Filler involves only a small incision, and in most cases can be performed on an outpatient basis. Large scale formal outcome trials involving hundreds of patients with follow-up out to eight years show no detectable effect on normal walking in any of the patients.
Those patients who have positive physical exam findings, positive MR neurography findings and a clear positive response to MRI guided piriformis injection have had a 85% to 90% good to excellent outcome.
Get Expert Diagnosis and Treatment
If you're experiencing sciatica or buttock pain, don't wait. Contact us today to schedule a consultation with Dr. Aaron Filler.
