Letter to the Editor: Role of the Piriformis Muscle in Pelvic Pain: Beyond the “Sciatica Muscle”

Dear Editor:

Pelvic pain is a common condition that affects public health significantly.¹ This pain is one of the presentations of pelvic-floor dysfunction. Pelvic pain is also important because it is a chronic pain pattern.¹ A multidisciplinary approach is essential for diagnosis, differential diagnosis, and treatment. In addition to gynecologic and urologic etiologies, musculoskeletal pathologies can also be present in the differential diagnosis of pelvic pain.² Examples include sacroiliac dysfunction, fascial pathologies, and myofascial pain syndrome.³

Myofascial pain syndrome is a condition that is very common but often underdiagnosed. Indeed, in regions where skeletal musculature is present, the potential for myofascial pain syndrome is inherent.³ Sometimes it appears as a primary problem but, more often, it accompanies a primary pathology. Trigger points may not cause symptoms because they are often in a latent state. In areas with much load transmission, such as the pelvic region, latent trigger points can become active easily. This region—especially in patients with histories of cesarean section, abdominal surgery, and/or prostatectomy—becomes susceptible to myofascial pain syndrome.² Symptoms occur depending on the affected muscle. Abdominal muscles, obturator muscles, gemellus muscles, and pelvic-floor muscles may be affected in this region—not just the piriformis muscle.³

In this region, the piriformis muscle is an important muscle that bridges the hip and pelvis, bears weight during sitting, and has neurovascular neighbors.⁴ This muscle's relationship to the sacroiliac joint and contribution to sacroiliac dysfunction also play a critical role in pelvic pain.⁴ Although the piriformis muscle is referred to as the “sciatica muscle” in musculoskeletal practice, myofascial pain syndrome of the piriformis muscle has also been associated with pelvic pain, impotence, incontinence, and painful sexual intercourse.³

Both an interview and a physical examination are imperative for accurate diagnosis. It is crucial to locate trigger points meticulously, with particular emphasis on the ∼ ⅓ origin and ⅓ insertion regions of the muscle (Fig. 1A). Stretching exercises, physical therapy modalities, and invasive techniques can be used in treatment.⁵ The patient should be in a prone position during invasive treatments (Fig 1B and C). Ultrasonographic guidance is recommended during intervention on the piriformis muscle due to sciatic-nerve variations. To avoid the sciatic nerve, the ⅓ origin and ⅓ insertion of the muscle should be targeted (Fig. 1B and C). During treatment, a 0.3 x 60–70-mm acupuncture needle should be inserted perpendicularly into the muscle. Although there is no clear protocol regarding treatment frequency, a total of 3 sessions per week is recommended.

FIG. 1.

(A) Locations of trigger points and area of pain radiation of the piriformis muscle. (B) Patient positioning and dry needling treatment targeting ⅓ insertion of the piriformis muscle with the flat palpation technique (C) Patient positioning and dry needling treatment targeting ⅓ origin of the piriformis muscle with the flat palpation technique.

The data that support this Letter are available from the corresponding author, upon reasonable request.