The Gluteal Region Flashcards
Outline the cutaneous innervation of the gluteal region.
The cutaneous innervation of the gluteal region is divided into four quadrants—upper anterior, upper posterior, lower anterior, and lower posterior:
(a) Upper anterior quadrant is supplied by the:
– lateral cutaneous branch of subcostal nerve (T12), and
– lateral cutaneous branch of iliohypogastric nerve (L1).
(b) Upper posterior quadrant is supplied by the cutaneous branches from dorsal rami of upper three lumbar nerves (L1, L2, L3) and upper three sacral nerves (S1, S2, S3).
(c) Lower anterior quadrant is supplied by the posterior division of the lateral cutaneous nerves of the thigh.
(d) Lower posterior quadrant is supplied by the:
– posterior cutaneous nerves of the thigh (S1, S2, S3), and
– perforating cutaneous nerves (S2, S3).
State the nerve roots of the pudendal nerve.
S2, S3, S4
State the nerve roots of the posterior femoral cutaneous nerve and its distribution.
S1, S2, S3
Distribution: lower gluteal region by inferior cluneal nerves
State the pattern of blood supply to gluteus maximus.
Segmental blood supply
Which arteries form the spinous anastomosis?
The superior gluteal artery anastomoses with the deep circumflex iliac artery and the ascending branch of the lateral circumflex femoral artery at the ASIS.
State causes of Trendelenburg’s sign.
- paralysis of gluteus medius and minimus
- dislocation of the hip joint
- fractures of the neck of femur
- collapse of the head of femur e.g. from avascular necrosis, slipped epiphysis, tuberculosis of head of femur
- severe arthritis of the hip joint
Comment on sciatic hernias.
- Occurs when pelvic structures protrude through the greater sciatic foramen
- It compresses the contents of the foramen and may present with pain, numbness and weakness in the lower limb if sciatic nerve is compressed
What are some clinical notes regarding the sciatic nerve?
- can be compressed at lower border of gluteus maximus by sitting on a bench with a sharp edge
- may be injured by misplaced deep intramuscular injections. To prevent this, the injection is usually given in the superolateral quadrant.
- May be injured in posterior dislocation of the hip joint.
Comment on trochanteric bursitis.
The bursa between the greater trochanter and the gluteal aponeurosis may be a site of infection. Symptoms:
1) pain or a burning sensation in the hip or outer edge of the upper thigh, with the feeling sometimes travelling toward the knee but rarely crossing the knee
2) tenderness over the outer hip bone area
3) pain when lying and sleeping on the affected side
NOTE: The gluteal aponeurosis is a fibrous membrane from the fascia lata, that lies between the iliac crest and the superior border of the gluteus maximus. A part of the gluteus medius arises from this membrane.
What is the clinical significance of the ischial spine?
It is used as an anatomical landmark for the administration of a pudendal nerve block.
a) What are the root values of the perforating cutaneous nerve?
b) Which structure does it pierce?
c) What part of the skin does it supply?
a) S2, S3
b) lower part of sacrotuberous ligament
c) posteroinferior quadrant of gluteal region
State the actions of tensor fascia lata.
- abducts thigh
- medially rotates thigh
- flexes thigh
- mainly, helps to keep knee extended
State the gluteal muscles involved in the following movements of the hip joint:
a) extension
b) abduction
c) internal rotation
d) external rotation
a) gluteus maximus
b) gluteus medius and minimus
c) gluteus medius and minimus
d) gluteus maximus and the small muscles
Notes:
- Piriformis muscle can abduct the thigh only if it is flexed.
- In paralysis of the quadriceps unit, gluteus maximus can be an active but weak knee extensor.
State the function of:
a) gluteus maximus
b) gluteus medius and minimus
a) Chief antigravity muscle of the hip
b) Prevents the sagging of pelvis on the unsupported side/pelvic stabilizers
What type of joint is the sacroiliac joint, and what ligament is mainly responsible for its static stability?
Synovial planar joint
Sacroiliac ligament