Lower Limb Anatomy: Pelvis, Hip Joint, and Related Structures (Vocabulary)

Vocabulary flashcards covering key terms from the lecture on the lower limb, pelvis, hip joint, and related structures.

Gluteal region

The buttock region containing the gluteal muscles (maximus, medius, minimus) and lateral rotators; important for hip movement and stability.

Perineum

The space below the trunk between the thighs, containing the external genitalia and the anus.

Popliteal fossa

The posterior knee region; a diamond-shaped area behind the knee where vessels and nerves pass.

Inguinal region

The transition area between the trunk and thigh where the inguinal ligament is located.

Inguinal ligament

A fibrous band from the anterior superior iliac spine to the pubic tubercle; forms the inferior border of the inguinal region.

Pelvic girdle

The pair of hip bones that form a girdle linking the free lower limbs to the axial skeleton.

Bony pelvis

The ring formed by two hip bones plus the sacrum and coccyx; includes acetabulum and pelvic walls.

Os coxae

Another name for the hip bone (one on each side), forming part of the pelvic girdle.

Ilium

The largest part of the hip bone with the iliac crest (the wing of the pelvis).

Ischium

Posterior-inferior part of the hip bone; contains the ischial tuberosity and ramus.

Pubis

Anterior part of the hip bone; contributes to the acetabulum; includes the pubic body and superior/inferior rami.

Acetabulum

The cup-shaped socket formed by the ilium, ischium, and pubis; articulates with the femoral head.

Acetabular notch

Inferior gap in the acetabulum, bridged by the transverse acetabular ligament to complete the socket.

Lunate surface

The crescent-shaped articular surface around the acetabulum that contacts the femoral head.

Iliac crest

The superior border of the ilium; a palpable ridge along the top of the hip bone.

Anterior superior iliac spine (ASIS)

Prominent anterior projection; origin for sartorius; reference point on the pelvis.

Anterior inferior iliac spine (AIIS)

Anterior-inferior projection; origin for rectus femoris.

Posterior superior iliac spine (PSIS)

Posterior projection on the ilium; attachment for ligaments; less clinically emphasized in lecture.

Pubic symphysis

Fibrocartilaginous joint between the left and right pubic bones; relatively immovable in adults.

Pectin pubis

Sharp internal line on the superior pubic ramus where the pectineus muscle attaches; also called pectineal line.

Obturator foramen

Large circular opening formed by the pubis and ischium; closed by the obturator membrane; passage for obturator vessels and nerve; attachment for obturator muscles.

Obturator membrane

Fibrous membrane closing the obturator foramen; provides attachment for obturator muscles.

Greater sciatic notch

Notch in the ilium that, with ligaments, forms the greater sciatic foramen to allow passage of nerves/vessels (e.g., sciatic nerve).

Lesser sciatic notch

Notch below the greater notch; forms the lesser sciatic foramen for structures such as the tendon of obturator internus and related nerves/vessels.

Ischial spine

Prominent projection on the ischium; separates the greater and lesser sciatic notches; attachment for ligaments.

Iliotibial tract

Thickened lateral band of fascia lata running from the iliac crest to the tibia; coordinates hip and knee movement.

Tensor fasciae latae

Muscle that tightens the fascia lata and inserts into the iliotibial tract; originates from the ASIS/iliac crest.

Fascia lata

Deep fascia of the thigh that envelopes compartments and is continuous with the crural fascia and IT band.

Crural fascia

Deep fascia of the leg; envelops the leg and forms part of the leg's compartmental separation.

Iliopsoas

Main hip flexor; formed by psoas major and iliacus; passes under the inguinal ligament to attach to the femur.

Anterior thigh compartment

Compartment containing knee extensors (quadriceps) and hip flexors; functions include knee extension and hip flexion.

Medial thigh compartment

Medial (adductor) compartment; contains adductor muscles that adduct the thigh.

Posterior thigh compartment

Hamstrings; knee flexors and hip extensors.

Leg compartments (anterior, lateral, posterior)

Anterior leg: dorsiflexors; Lateral leg: evertors; Posterior leg: plantarflexors and toe flexors.

Abdominal aorta

Main artery of the abdomen; bifurcates into common iliac arteries at the lower lumbar region.

Common iliac arteries

Split of the abdominal aorta into left and right arteries; each divides into internal and external iliac arteries.

External iliac artery

Continuation of the common iliac that becomes the femoral artery to supply the lower limb.

Internal iliac artery

Branch of the common iliac that supplies the pelvic organs.

Femoral artery

Main artery of the thigh; becomes the popliteal artery behind the knee.

Popliteal artery

Continuation of the femoral artery behind the knee; divides into anterior and posterior tibial arteries.

Anterior tibial artery

Branch of the popliteal; runs anteriorly in the leg and becomes dorsalis pedis on the foot.

Posterior tibial artery

Branch of the popliteal; runs posteriorly in the leg and gives off the fibular (peroneal) artery.

Fibular (peroneal) artery

Branch of the posterior tibial artery supplying the lateral compartment of the leg.

Greater saphenous vein

Large superficial vein running along the medial leg and thigh; drains into the femoral vein.

Small saphenous vein

superficial vein running along the posterior calf; drains into the popliteal vein.

Femoral vein

Major deep vein of the thigh; continues as external iliac vein to join the common iliac veins.

Popliteal vein

Deep vein behind the knee; continuation of the femoral vein through the popliteal fossa.

Inferior vena cava

Large vein that returns systemic venous blood to the heart from the lower body; formed by the joining of common iliac veins.

Lumbar plexus

Network of ventral rami (L1-L4) that supplies the anterior and medial compartments of the thigh; contributes to the lumbosacral plexus.

Sacral plexus

Network of ventral rami (S1-S4) that supplies the posterior aspect of the lower limb and pelvis; interconnects with the lumbar plexus.

Sciatic nerve

Largest nerve of the lower limb; a major branch of the lumbosacral plexus that divides into tibial and common fibular nerves.

Tibial nerve

Medial division of the sciatic nerve; supplies the posterior compartment of the leg and plantar foot.

Common fibular (peroneal) nerve

Lateral division of the sciatic nerve; supplies the anterior and lateral compartments of the leg.

Femoral nerve

Nerve of the lumbar plexus; supplies the anterior thigh muscles.

Obturator nerve

Nerve from the lumbar plexus; supplies the medial thigh muscles.

Gluteal nerves

Nerves supplying the gluteal muscles (superior and inferior gluteal nerves).

Dermatome

Area of skin supplied by a single spinal nerve or segment; used to map nerve injury.

Myotome

Group of muscles supplied by a single spinal segment; used to assess motor function and nerve integrity.

Hip joint

Ball-and-socket synovial joint between the acetabulum and the femoral head; allows multiple movements (flexion/extension, abduction/adduction, rotation, circumduction).

Knee joint

Synovial hinge joint between the femur, tibia, and patella; primarily flexion and extension; fibula does not form part of the knee joint.

Tibia vs. fibula orientation

Tibia is the medial, weight-bearing bone; fibula is the lateral, non-weight-bearing bone.

Talus

Ankle bone that articulates with the tibia and fibula to form the ankle joint; sits atop the calcaneus.

Calcaneus

Heel bone; the largest tarsal bone bearing the heel; forms the heel with the calcaneal tuberosity.

Navicular

Tarsal bone anterior to talus; articulates with the talus and three cuneiforms.

Cuneiforms

Three wedge-shaped tarsal bones (medial, intermediate, lateral) articulating with the navicular and metatarsals.

Cuboid

Tarsal bone on the lateral side articulating with the calcaneus and the fourth and fifth metatarsals.

Metatarsals

Five long bones in the foot; each has a base, shaft, and head; articulate with the tarsals and phalanges.

Phalanges

Bones of the toes; digits 2-5 have proximal, middle, and distal phalanges; the hallux has two phalanges.

Tarsal tunnel

Tunnel behind the medial malleolus containing tendons, vessels, and tibial nerve.

What is the Gluteal region?

The buttock region containing the gluteal muscles (maximus, medius, minimus) and lateral rotators; important for hip movement and stability.

What is the Perineum?

The space below the trunk between the thighs, containing the external genitalia and the anus.

What is the Popliteal fossa?

The posterior knee region; a diamond-shaped area behind the knee where vessels and nerves pass.

What is the Inguinal region?

The transition area between the trunk and thigh where the inguinal ligament is located.

What is the Inguinal ligament?

A fibrous band from the anterior superior iliac spine to the pubic tubercle; forms the inferior border of the inguinal region.

What is the Pelvic girdle?

The pair of hip bones that form a girdle linking the free lower limbs to the axial skeleton.

What is the Bony pelvis?

The ring formed by two hip bones plus the sacrum and coccyx; includes acetabulum and pelvic walls.

What is the Os coxae?

Another name for the hip bone (one on each side), forming part of the pelvic girdle.

What is the Ilium?

The largest part of the hip bone with the iliac crest (the wing of the pelvis).

What is the Ischium?

Posterior-inferior part of the hip bone; contains the ischial tuberosity and ramus.

What is the Pubis?

Anterior part of the hip bone; contributes to the acetabulum; includes the pubic body and superior/inferior rami.

What is the Acetabulum?

The cup-shaped socket formed by the ilium, ischium, and pubis; articulates with the femoral head.

What is the Acetabular notch?

Inferior gap in the acetabulum, bridged by the transverse acetabular ligament to complete the socket.

What is the Lunate surface?

The crescent-shaped articular surface around the acetabulum that contacts the femoral head.

What is the Iliac crest?

The superior border of the ilium; a palpable ridge along the top of the hip bone.

What is the Anterior superior iliac spine (ASIS)?

Prominent anterior projection; origin for sartorius; reference point on the pelvis.

What is the Anterior inferior iliac spine (AIIS)?

Anterior-inferior projection; origin for rectus femoris.

What is the Posterior superior iliac spine (PSIS)?

Posterior projection on the ilium; attachment for ligaments; less clinically emphasized in lecture.

What is the Pubic symphysis?

Fibrocartilaginous joint between the left and right pubic bones; relatively immovable in adults.

What is the Pectin pubis?

Sharp internal line on the superior pubic ramus where the pectineus muscle attaches; also called pectineal line.

What is the Obturator foramen?

Large circular opening formed by the pubis and ischium; closed by the obturator membrane; passage for obturator vessels and nerve; attachment for obturator muscles.

What is the Obturator membrane?

Fibrous membrane closing the obturator foramen; provides attachment for obturator muscles.

What is the Greater sciatic notch?

Notch in the ilium that, with ligaments, forms the greater sciatic foramen to allow passage of nerves/vessels (e.g., sciatic nerve).

What is the Lesser sciatic notch?

Notch below the greater notch; forms the lesser sciatic foramen for structures such as the tendon of obturator internus and related nerves/vessels.

What is the Ischial spine?

Prominent projection on the ischium; separates the greater and lesser sciatic notches; attachment for ligaments.

What is the Iliotibial tract?

Thickened lateral band of fascia lata running from the iliac crest to the tibia; coordinates hip and knee movement.

What is the Tensor fasciae latae?

Muscle that tightens the fascia lata and inserts into the iliotibial tract; originates from the ASIS/iliac crest.

What is the Fascia lata?

Deep fascia of the thigh that envelopes compartments and is continuous with the crural fascia and IT band.

What is the Crural fascia?

Deep fascia of the leg; envelops the leg and forms part of the leg's compartmental separation.

What is the Iliopsoas?

Main hip flexor; formed by psoas major and iliacus; passes under the inguinal ligament to attach to the femur.

What is the Anterior thigh compartment?

Compartment containing knee extensors (quadriceps) and hip flexors; functions include knee extension and hip flexion.