Gluteal Region and Posterior Thigh - Vocabulary Flashcards

Vocabulary flashcards covering muscles, nerves, vessels, landmarks, and clinical correlations from the gluteal region and posterior thigh.

Superior gluteal nerve

Motor nerve that exits the pelvis superior to the piriformis and innervates gluteus medius, gluteus minimus, and tensor fascia lata.

Inferior gluteal nerve

Motor nerve that exits the pelvis inferior to the piriformis and innervates the gluteus maximus.

Sciatic nerve

The major nerve of the posterior thigh; exits the pelvis via the greater sciatic foramen and typically splits into tibial and common fibular components in the thigh.

Tibial component of the sciatic nerve

Branch of the sciatic nerve that continues down the leg to innervate most of the posterior compartment muscles and plantar foot muscles.

Common fibular (peroneal) component of the sciatic nerve

Branch of the sciatic nerve that travels laterally and supplies the short head of the biceps femoris; later divides into superficial and deep branches.

Nerve to obturator internus

Ventral ramus nerve exiting the greater sciatic foramen inferior to the piriformis; innervates obturator internus and gemellus superior.

Nerve to quadratus femoris

Ventral ramus nerve exiting the greater sciatic foramen inferior to the piriformis; innervates quadratus femoris and gemellus inferior.

Pudendal nerve

Nerve exiting the greater sciatic foramen and entering the lesser sciatic foramen to innervate perineal structures.

Obturator nerve

Nerve passing through the obturator foramen; splits into anterior and posterior divisions to innervate medial thigh muscles.

Femoral nerve

Main nerve of the anterior thigh; supplies quadriceps, sartorius, and pectineus; femoral artery becomes popliteal after passing through the adductor hiatus.

Deep femoral artery (profunda femoris)

Primary blood supply to the thigh via perforating branches; gives off medial and lateral circumflex arteries and perforating arteries.

Lateral circumflex femoral artery

Branch of the profunda femoris with descending, transverse, and ascending branches; contributes to hip/thigh vascular networks and cruciate anastomosis.

Medial circumflex femoral artery

Branch of the profunda femoris that wraps posterior to the femur to supply the femoral head/neck and participates in the cruciate anastomosis.

Descending branch of the lateral circumflex femoral artery

Branch of LCFA that travels downward and participates in the hip/thigh anastomotic networks.

First perforating artery

The initial perforating branch of the profunda femoris; ascends the posterior thigh and contributes to cruciate anastomosis.

Perforating arteries (4 total)

Series of arteries from the profunda femoris that perforate the adductor magnus to supply the posterior thigh and anastomose with other vessels.

Cruciate anastomosis

Arterial network around the hip formed by inferior gluteal, medial and lateral circumflex femoral arteries, and first perforating artery for collateral flow.

Piriformis

Pelvic muscle that originates on the sacrum and exits via the greater sciatic foramen to insert on the greater trochanter; abducts and laterally rotates the thigh; innervated by S1–S2.

Gemellus superior

Deep gluteal muscle; originates at the ischial spine and inserts with obturator internus; laterally rotates and abducts the thigh; innervated by the nerve to obturator internus.

Gemellus inferior

Deep gluteal muscle; originates at the ischial tuberosity; inserts with obturator internus; laterally rotates and abducts the thigh; innervated by the nerve to quadratus femoris.

Obturator internus

Deep gluteal muscle; originates on inner obturator membrane and margins; exits through the greater sciatic foramen; laterally rotates and abducts the thigh; innervated by nerve to obturator internus.

Quadratus femoris

Deep rotator; originates from ischial tuberosity and inserts on intertrochanteric crest; laterally rotates thigh; innervated by nerve to quadratus femoris.

Gluteus maximus

Largest hip extensor; extends thigh, laterally rotates, and helps stabilize the knee via the IT band; innervated by the inferior gluteal nerve.

Gluteus medius

Abducts the thigh; posterior fibers assist lateral rotation; level the sacral base; innervated by the superior gluteal nerve; inserts on the greater trochanter.

Gluteus minimus

Deep to gluteus medius; abducts and medially rotates the thigh; helps level the sacral base; innervated by the superior gluteal nerve.

Tensor fascia lata (TFL)

Originates near the ASIS on the iliac crest; inserts into the IT band; flexes/adducts/medially rotates the thigh; maintains extended knee; innervated by the superior gluteal nerve.

Gluteal aponeurosis

Fibrous sheet over gluteus medius creating a fascial plane; used to access the plane between gluteus medius and maximus during dissection.

Iliotibial tract (IT band)

Lateral fascia band running from the TFL to the lateral tibia; stabilizes the knee and assists in thigh movement.

Greater sciatic foramen

Pelvic opening through which structures exit the pelvis; superior to piriformis transmits superior gluteal vessels/nerves, inferior transmits sciatic nerve and inferior gluteal vessels.

Lesser sciatic foramen

Opening through which structures pass from gluteal region to perineum; transmits pudendal nerve and obturator internus etc.

Sacrotuberous ligament

Ligament connecting sacrum to the ischial tuberosity; limits nutation; helps form greater and lesser sciatic foramina.

Sacrospinous ligament

Ligament connecting sacrum to ischial spine; forms boundaries of the greater and lesser sciatic foramina.

Nutation

Anterior tilt of the sacrum relative to the ilium; limited by sacrospinous and sacrotuberous ligaments.

Counternutation

Posterior tilt of the sacrum relative to the ilium; opposite of nutation.

Adductor hiatus

Opening in the distal femur allowing femoral artery and vein to pass to become the popliteal artery and vein.

Hamstrings (posterior thigh group)

Group of thigh extensors and leg flexors including biceps femoris (long and short heads), semitendinosus, and semimembranosus.

Biceps femoris long head

Extends the thigh and flexes/externally rotates the leg; innervated by the tibial part of the sciatic nerve.

Biceps femoris short head

Flexes the leg; does not cross the hip; innervated by the common fibular part of the sciatic nerve.

Semitendinosus

Extends the thigh; flexes/medially rotates the leg; inserts on the pes anserinus area of the tibia; innervated by the tibial part of the sciatic nerve.

Semimembranosus

Extends the thigh; flexes/medially rotates the leg; located medially with a broad distal tendon; innervated by the tibial part of the sciatic nerve.

Avulsion fracture

Tendon pulls off a piece of bone at its insertion, common in hamstring injuries; can endanger nearby nerves.

Piriformis syndrome

Compression or entrapment of the sciatic nerve by the piriformis leading to buttock radiating pain.

Trendelenburg gait

Gait pattern due to superior gluteal nerve weakness; pelvis drops on the opposite side; patient leans toward the affected side to compensate.