New Piriformis Syndrome Studies Clarify Butt Pain
Piriformis syndrome could be described as a pain in the butt along with pain in the lower back, hip, and the back of the leg that can be debilitating. Several new studies shed some light on this challenging condition and how to treat it effectively.
Before I conducted my own research and self-diagnosed the severe pain, loss of sensation in my foot, and inability to walk more than a few steps as piriformis syndrome (later verified by a physician), I had never heard of this condition. Although WebMd describes it as “an uncommon neuromuscular disorder,” it is not that uncommon among those who engage in long-distance running, an activity I had enjoyed for more than a decade.
Piriformis syndrome can occur when the piriformis muscle spasms and compresses the sciatic nerve. The piriformis muscle is located in the buttocks near the top of the hip joint, and the sciatic nerve can either go through or next to the muscle.
The piriformis muscle is necessary for lower body movement, including walking, shifting from side to side, rotating the thighs, stabilizing the hips, and maintaining balance. The sciatic nerve runs from the butt down the back of the leg and disperses into smaller nerves in the feet.
Thus it’s easy to see how problems with this combination of structures can cause pain and mobility issues. Treatment can range from application of ice and heat to rest, certain exercises to reduce impact on the sciatic nerve, use of anti-inflammatory or muscle relaxant drugs, chiropractic, injections of corticosteroids or botox, and surgery in severe cases.
Better understanding of piriformis syndrome: study
When surgery seems to be the only solution for people with piriformis syndrome, surgeons should have all the information available. A new study in Surgical and Radiologic Anatomy reports on various anatomical variations between the sciatic nerve and piriformis muscle that can aid surgeons in their work.
The authors examined the gluteal area (buttocks) of 147 cadavers (294 limbs) and discovered the following:
- The piriformis muscle and sciatic nerve relationship was typical in 93.6 percent (275 limbs) of the cases
- In 12 limbs (4.1%), the common peroneal nerve (a branch of the sciatic nerve that provides sensation and movement to the lower leg and foot) passed through a double piriformis while the tibial nerve ran below it. The latter situation can result in foot pain.
- In seven limbs, there were other variations, such as both nerves running above the piriformis, both nerves penetrating the piriformis, among others.
These findings are important for surgeons who perform procedures on individuals with piriformis syndrome, as 6.4 percent of the limbs examined showed anatomical variations. Thus, doctors should expect the unexpected.
Stretching and piriformis syndrome
Use of stretching exercises to work the piriformis muscle is typically recommended as a treatment for piriformis syndrome. Based on personal experience, I find that regular stretching is not only helpful but necessary.
A recent report in Medical Engineering & Physics compared two conventional stretching techniques for piriformis syndrome using three-dimensional modeling and seven volunteers. The volunteers underwent a series of CT scans while in the three stretches recommended for this syndrome; namely hip flexion, hip adduction, external rotation.
The authors then constructed three-dimensional bone models using the CT scans and optimized the stretches. They discovered that when the following factors were considered, it was possible to elongate the piriformis muscle by 30 to 40 percent when compared to conventional stretches, which provided about a 15 percent increase.
Those factors are:
- Placing the hip joints in a 115 degree of hip flexion, 40 degree of external rotation, and 25 degree of adduction, or
- 120 degree of hip flexion, 50 degree of external rotation, and 30 degrees of adduction
While these figures may be Greek to the layperson, physical therapists and other knowledgeable medical professionals can use this information to help individuals who have piriformis syndrome. The authors noted that these optimized stretches resulted in greater increases in the length of the piriformis muscle and “may be more easily performed by some patients due to increased hip flexion.”
Piriformis syndrome and muscle injections
If your doctor has recommended muscle injections for piriformis syndrome, usually of lidocaine plus triamcinolone, there are two techniques he or she may follow: fluoroscopic or ultrasound-guidance to locate the muscle. Is one technique better than the other?
In a comparative trial, 28 patients with piriformis syndrome were randomly assigned to receive a lidocaine and triamcinolone injection via either ultrasound or fluoroscopy. The patients in both groups reported similar pain relief, satisfaction, and improvement in most functional outcomes.
In addition, the clinicians noted no difference in the time it took to complete the procedure. However, there was some difference between the two groups in the ability to perform some functions; that is, outdoor and household chores. Anyone who is considering piriformis muscle injections should discuss the options with their clinician.
According to Sciatica.org, piriformis syndrome was once believed to cause 6 percent of sciatica, but advanced diagnostic techniques have shown it to be “significantly more common.” If you have piriformis syndrome or think you may be suffering with this condition, keep up with the latest studies and consult a knowledgeable medical professional to help you alleviate your pain and any disabilities.
Fowler IM et al. A randomized comparison of the efficacy of 2 techniques for piriformis muscle injection: ultrasound-guided versus nerve stimulator with fluoroscopic guidance. Regional Anesthesia and Pain Medicine 2014 Mar-Apr; 39(2): 126-32
Gulledge BM et al. Comparison of two stretching methods and optimization of stretching protocol for the piriformis muscle. Medical Engineering & Physics 2014 Feb; 36(2): 212-18
Natsis K et al. Anatomical variations between the sciatic nerve and the piriformis muscle: a contribution to surgical anatomy in piriformis syndrome. Surgical and Radiologic Anatomy 2014 Apr; 36(3): 273-80