Piriformis Syndrome - A Pain in the Butt

Pain along the backside of the leg is a common condition which occurs in 2.2-19.5% of the population per year. While the cause of sciatica is frequently attributed to a herniated disc in the back, this is not always the cause. The piriformis muscle, a small muscle in the buttocks region, can also cause compression of the sciatic nerve leading to pain.This blog post will discuss the causes of sciatica and treatment options for the treatment of piriformis syndrome. 

Disc herniations are frequently thought of as the cause of lower back pain and sciatica. While disc herniations can be the cause lower back pain and sciatica, the correlation between disc herniations and pain is pretty poor. 

A study in the American Journal of Neuroradiology looked at 3110 individuals without pain to figure out how common spinal abnormalities are in each decade of life. The study found disc bulges in 30% of asymptomatic (without symptoms) 20 year olds, with the amount of disc bulges increasing with each decade of life. The same pattern was found with disc protrusions, starting at 29% of asymptomatic 20 year olds. 

Since the frequency of disc abnormalities is so high in the general population, the amount of sciatica cases caused by disc herniations is fairly low. 

A more common cause of sciatic nerve compression is by the piriformis muscle. The piriformis muscle is one of the stabilizing muscles of the pelvis which connects the sacrum (tailbone) to the femur (leg). The sciatic nerve lies underneath the piriformis muscle and sometimes courses through the piriformis muscle, making it susceptible to compression if the piriformis muscle is in spasm. 

Piriformis syndrome is essentially an overuse syndrome because of a dysfunction in the core. If the core muscles are unable to stabilize the lower back and pelvic, the piriformis muscle will go into spasm to provide the core with more stability. As mentioned before, if the piriformis muscle goes into spasm, the piriformis muscle can cause compression of the sciatic nerve leading to nerve irritation. 

The conservative treatment of piriformis syndrome includes joint mobilization, soft tissue therapy, and corrective exercise. The first goal of treatment is to decrease pain and nerve irritation since pain will alter movement patterns. Joint mobilization and manual therapy both stimulate mechanoreceptors which will decrease pain and muscle tone. The quick stretch to muscles with joint mobilization resets muscle spindle receptors while manual therapy stimulates ruffini and interstitial receptors. 

Self myofascial work is a great supplement to joint mobilization and manual therapy. This would include foam rolling and lacrosse ball work to decrease the muscle spasm and pain in the gluteal region. 

Once the pain level is reduced, improving the strength of the core muscles will alleviate the workload on the piriformis muscle. Targeting the gluteals and core muscles with clamshells, bridges, planks, and side planks can be beneficial in the beginning to learn how to use specific stabilizing muscles. However, the goal of core exercises should be to build strength and endurance by integrating with more complex movements, such as lunges and squats. 

Piriformis syndrome is a common cause of sciatica. The diagnosis of piriformis syndrome can be made with a thorough history and examination, and imaging is usually not necessary. Conservative treatment is an effective treatment option to decrease the pain seen with sciatica caused by piriformis spasm. 

If you are suffering from back along the backside of the leg, schedule a free 15-minute consultation with us to see how we can help you.

References:  

Brinjikji W, et. al. “Systematic Literature Review of Imaging Features of Spinal Degeneration in Asymptomatic Populations.” Am J Neuroradiol (2014): 1-6

Hopayian, Kevork, Fujian Song, Ricardo Riera, and Sidha Sambandan. "The Clinical Features of the Piriformis Syndrome: A Systematic Review." European Spine Journal Eur Spine J 19.12 (2010): 2095-109.