Gluteal Region and Posterior Thigh Flashcards
Gluteal Region
large transitional zone between the trunk and the lower limb
-Physically part of the trunk
-Functionally part of the lower limb
Gluteal ligaments
sacrotuberous ligament and sacrospinous ligament
Sacrotuberous ligament
converts the sciatic notch into a foramen
Sacrospinous ligament
Subdivides the sciatic foramen:
1. Greater sciatic foramen: passageway for structures in/out of the pelvis (sciatic nerve)
2. Lesser sciatic foramen: passageway for structures in/out of the perineum
Gluteus maximus
I: IT band
Inn: inferior gluteal n.
Action(s): extends the thigh & assists in lateral rotation; steadies the hip & assists in rising from a sitting position
Gluteus medius
Inn: superior gluteal n.
Action(s): abducts & medially rotates hip; keeps pelvis level when ipsilateral limb is weight bearing
Gluteus minimus
Inn: superior gluteal n.
Action(s): abducts & medially rotates hip; keeps pelvis level when ipsilateral limb is weight bearing
Trendelenburg’s sign
Contraction of the gluteus medius & minimus mm. prevent excessive pelvis tilt
-Trendelenburg’s sign occurs in people with weak or paralyzed abductor muscles of the hip
-Two types of gait:
uncompensated: the opposite hip drops when standing on the affected side
compensated: trunk bends to the affected side
Trendelenburg’s sign usually uncompensated gait
Tensor Fasciae latae
O: Anterior superior iliac psine (ASIS) & anterior iliac crest
I: IT band
Inn: superior gluteal n.
Action(s): abducts, medially rotates & flexes thigh; helps to keep knee extended
Piriformis
Inn: nerve to piriformis (anterior rami of S1-S2)
Action(s): laterally rotates extended thigh; abducts flexed thigh; stabilizes hip joint
obturator internus
Inn: nerve to obturator internus
Action(s): laterally rotates extended thigh; abducts flexed thigh; stabilizes hip joint
Superior and inferior gemelli
Inn: superior- nerve to the obturator internus
inferior- nerve to the quadratus femoris
Action(s): laterally rotates extended thigh; abducts flexed thigh; stabilizes hip joint
Quadratus femoris muscle
Inn: nerve to the quadratus femoris
Action(s): laterally rotates thigh; stabilizes hip joint
Arteries of the gluteal region
- Superior gluteal a.: exits the greater sciatic foramen superior to the piriformis m., branches into a superficial and deep branch
- Inferior gluteal a.: exits the greater sciatic foramen inferior to the piriformis m.
Ischial bursitis
inflammation of bursa at ischium, common in people who sit down a lot
Posterior compartment of the thigh
M: semitendinosus, semimembranosus, biceps femoris
Inn: tibial division of sciatic n., common tibular division of sciatic n.
Semitendinosus
O: ischial tuberosity
I: Superior part of medial surface of tibia (pes anserinus)
Inn: tibial division of sciatic n.
Action(s): extends the thigh & flexes the leg
-Medially rotates knee when flexed
-Can extend trunk when thigh and leg are flexed
Pes anerinus
“Say Grace with Tea”
insertion of sartorius, gracilis, semitendinosus
All are flexors of the knee- provide medial support to the knee when extended
Semimembranosus
O: ischial tuberosity
I: posterior part of the medial condyle of the tibia
Inn: tibial division of sciatic n.
Action(s): extends the thigh & flexes the leg
-Medially rotates knee when flexed
-Can extend trunk when thigh and leg are flexed
Biceps femoris
O: long head- ischial tuberosity
short head- linea aspera & lateral supracondylar line of the femur
I: lateral side of the head of the fibula
Inn: long head- tibial division of sciatic n.
short head- common fibular division of sciatic n.
Action(s): flexes the leg & rotates it laterally when flexed
-Long head- extends the thigh
Sciatic nerve
L4-S3
Lies on the adductor magnus m. and crossed by the long head of the biceps femoris m.
-Branches into:
1. Tibial n.
2. Common fibular n.
Common fibular n.
L4-S2
-Gives off lateral sural cutaneous n. (cutaneous)
Sciatica
-Pain in the distribution of the sciatic nerve
-Pain is felt in the buttock, posterior thigh, and posterolateral aspect of the leg around the lateral malleolus to the lateral dorsum of the foot and the entire sole
-Usually caused by herniated disc or bone spur
Genicular anastomosis
A network of vessels around the knee that provide collateral circulation capable of supplying blood to the leg during full knee flexion.
1.Superior collateral supply
2. Popliteal artery (directly)
3. Inferior collateral supply
Boarders of the popliteal fossa
Superior: semitendinosus and semimembranosus (medial); biceps femoris m (lateral)
Inferior: medial head of gastrocnemius m (medial); lateral head of gastrocnemius m. (lateral)
Roof (posterior): popliteal fascia, skin
Floor (anterior): capsule of the knee joint, adjacent surfaces of the femur, tibia, and popliteus m.
Popliteal fossa contents
-Common fibular n.
-Tibial n.
-Popliteal v.
-Popliteal a.
-Popliteal lymph nodes
Baker’s cyst
accumulation of synovial fluid in the knee joint
