Piriformis Syndrome

Question 1

Action of piriformis muscle when LE straight.

Answer 1

ER at hip and thigh Extension

Question 2

Action of piriformis muscle when LE flexed 90 degrees at knee and hip.

Answer 2

Abduction of hip if it is in flexion.

Question 3

What leaves the pelvis via the same route as the piriformis muscle?

What leaves superior to the piriformis muscle?

Answer 3

Sacral plexus branches and internal iliac vessel.

**Leaving superior - Superior gluteal vessels and nerves.

Question 4

What leaves inferior to the piriformis muscle?

Answer 4

Exiting inferior to piriformis m. :

• Inferior gluteal vessels and nerves
• Pudendal vessels and nerve
• Post. femoral cutaneous nerve
• Nerves to the short external rotators of femur. Obturator internus, sup/inf gemelli, quadratus femoris. Except for piriformis and obturator externus

Question 5

Nerve that has variable course in relation to the piriformis muscle.

Answer 5

Sciatic nerve -
1. (most common) - leaves below mm
2. Leaves above and below
3 and 4 - it can pierce the muscle

Question 6

Pathophysiology of muscle spasm:

_____ in alpha motor output from CNS –> _____ gamma
firing –> _____ spasm (more trauma, more pain)
 Pain-Spasm cycle (positive feedback loop)
 Spasm then creates the described syndrome

Answer 6

INCREASE in alpha motor output from CNS –> INCREASE gamma
firing –> INCREASE spasm (more trauma, more pain)
 Pain-Spasm cycle (positive feedback loop)
 Spasm then creates the described syndrome

Question 7

Describe A delta fibers and C fibers in the brain.

Answer 7

• A delta fibers carry impulses to the neothalamus and
  somatosensory cortex for processing. Localization/Discrimination of pain type (where pain is)
• C fibers send impulses to variety of locations: brainstem, midbrain nuclei, cortical limbic system (address behavior modification, memories, etc.)

Question 8

What is the nociception theory?

Answer 8

Inflammation disrupts the balance between HABITUATION and SENSITIZATION (decreased pain).

Question 9

What is nervi neurvorum

Answer 9

Derived from dorsal nerve roots forming sciatic nerve. Many unmyelinated free nerve endings. Innervate the nerve root sheath and peripheral nerve sheath.

Inflammatory agents (histamine, serotonin, bradykinin, prostaglandins). Irritate and inflame epineurium. Activates nociceptive endings of nervi neurvorum

Nerve distribution pain WITHOUT neural deficit

Question 10

What is piriformis spasm (syndrome) due to?

Answer 10

sciatic neuritis due to piriformis spasm

Question 11

***Name the clinical presentation of piriformis syndrome

Answer 11

• Low back or buttock pain that radiates down the leg
• Tenderness over the piriformis muscle, Exacerbated by provocative testing or palpation
• Paresthesias along the course of the sciatic nerve
• Aggravated sx by prolonged sitting
• Absence of true neurologic deficit - DTR are intact and Motor intact

Question 12

Define
 Lasègue sign 
 Well Leg Raising Test 
 Pace sign 
 Freiberg sign

Answer 12

 Lasègue sign – Straight leg raise
 Well Leg Raising Test – Contralateral leg raise
 Pace sign – Pain and weakness with resisted
abduction and external rotation of the hip
 Freiberg sign – Pain with passive internal rotation (doesn’t like IR) of the extended thigh

Question 13

Define well leg raising test - 0-35 degrees, 35-70 degrees, 70+ degrees

Answer 13

0-35 = sciatic roots --> symptoms of radicular issue
35-70 = ???
70+ = joint pain

Question 14

Types of OMM for piriformis muscle

what yoga?

Answer 14

Counterstrain (F/Abd/slight Rot), ME, MFR

Pigeon position - stretches piriformis and psoas

Question 15

Five home treatments for piriformis syndrome

Answer 15

Home stretching - Figure 4 position stretch, Internal rotation, Pigeon Posture (yoga), Sway exercise

Warm baths to increase blood flow, decrease lactic acid, decrease spasm

Question 16

Last resort for piriformis treatment

Answer 16

Surgical transection of piriformis muscle

Question 17

Origin and insertion of piriformis

Answer 17

O: 2nd-4th sacral segment levels
I: greater trochanter

Question 18

Cardinal features of piriformis syndrome:

1. A history of trauma to the ___and ___ region
2. Pain in the region of the SI joint, _____ , and ___ muscle, extending down the lower limb and causing difficulty walking
3. Acute exacerbation of the symptoms by lifiting or stooping
4. A palpable, sausage-shaped mass in the buttocks, during an exacerbation of symptoms, that is markedly tender to pressure
5. A positive _____ test
6. ___ atrophy, depending on the duration of symptoms

Answer 18

1. A history of trauma to the sacroiliac and gluteal region
2. Pain in the region of the SI joint, greater sciatic notch, and piriformis muscle, extending down the lower limb and causing difficulty walking
3. Acute exacerbation of the symptoms by lifiting or stooping
4. A palpable, sausage-shaped mass in the buttocks, during an exacerbation of symptoms, that is markedly tender to pressure
5. A positive straight leg raising test
6. Gluteal atrophy, depending on the duration of symptoms

Question 19

**PE of piriformis - ease of what movement?

Answer 19

**ease of ER

Question 20

Difference between trigger point and tender point

Answer 20

(slide 40)

• Trigger point is painful RADIATION of pain distal to trigger point.
• Tender point is LOCAL tenderness of the muscle.