piriformis


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piriformis

[pir′ifôr′mis]
Etymology: L, pirum + forma
a flat pyramidal muscle lying almost parallel to the posterior margin of the gluteus medius. It is partly within the pelvis and partly at the back of the hip joint. It is innervated by branches of the first and second sacral nerves and functions to rotate the thigh laterally and to abduct and to help extend it. Compare obturator externus, obturator internus.

Piriformis

A muscle in the pelvic girdle that is closely associated with the sciatic nerve.
Mentioned in: Sciatica
References in periodicals archive ?
The psoas major and minor, as one unit, are the only muscles, besides the piriformis, that connect the vertebral column to the legs.
The PN arises from the S2-S4 roots of the sacral plexus, exiting the pelvis under the piriformis muscle through the greater sciatic foramen and descending ventral to the sacrotuberous ligament.
Contrast-enhanced CT showed rim-enhancing loculated collections with air pockets in the left piriformis and glutei (Figure 1) extending down to the vastus lateralis muscles (Figure 2).
RENEW Sitting atop the ball releases the lower lumbar, glutes, piriformis, hip flexors, abductors, and psoas by rolling gently, searching for the trigger points that cause pain and ginching.
It descends posteriorly, anterior to the sacral plexus and piriformis muscle but posterior to the internal pudendal artery.
Special imaging for nerves with magnetic resonance neurography can detect piriformis muscle syndrome--a condition in which the narrow piriformis muscle irritates or pinches the sciatic nerve.
Sciatic pain due to nerve pressure has three possible sources: bony spurs on the vertebrae pressing on the nerve, pressure from a damaged spinal disk, and muscle spasms--particularly in the piriformis muscle, which may tighten enough to press on the nerves and cause pain.
Sciatic pain ( occasionally the sciatic nerve runs through the piriformis muscle in the buttock.
CHICAGO -- Up to one-fourth of women with chronic pelvic pain also have piriformis or levator ani tenderness, according to a study presented by Dr.
Apart from tumors, other causes of sciatica-type pain in the absence of radiculopathy due to herniated nucleus pulposus include the following: arachnoiditis, discitis, hip disease, compartment syndrome of the posterior thigh, sciatic nerve injury from intramuscular injection or projectile, Lyme disease, herpes zoster, and piriformis syndrome (Greenberg, 2001).
Piriformis syndrome was covered inadequately, and presbyesophagus was hot listed at all.
There are many different diagnoses associated with CPP including vulvar pain syndromes, interstitial cystitis, levator ani syndrome, piriformis syndrome, vaginismus, anismus, dyspareunia, proctalgia fugax, constipation, pelvic floor tension myalgias, endometriosis, pudendal neuralgia, and/or rectal pain.