SECTION Review

The pelvic girdle attaches the legs to the axial skeleton. The hip joint is where the pelvic girdle and the leg come together. The hip is joined to the pelvic girdle by many muscles. In the gluteal region, the psoas major and iliacus form the iliopsoas. The large and strong gluteus maximus, gluteus medius, and gluteus minimus extend and abduct the femur. Along with the gluteus maximus, the tensor fascia lata muscle forms the iliotibial tract. The lateral rotators of the femur at the hip are the piriformis, obturator internus, obturator externus, superior gemellus, inferior gemellus, and quadratus femoris. On the medial part of the thigh, the adductor longus, adductor brevis, and adductor magnus adduct the thigh and medially rotate it. The pectineus muscle adducts and flexes the femur at the hip.

The thigh muscles that move the femur, tibia, and fibula are divided into medial, anterior, and posterior compartments. The medial compartment includes the adductors, pectineus, and the gracilis. The anterior compartment comprises the quadriceps femoris, quadriceps tendon, patellar ligament, and the sartorius. The quadriceps femoris is made of four muscles: the rectus femoris, the vastus lateralis, the vastus medius, and the vastus intermedius, which together extend the knee. The posterior compartment of the thigh includes the hamstrings: the biceps femoris, semitendinosus, and the semimembranosus, which all flex the knee.

The muscles of the leg that move the foot and toes are divided into anterior, lateral, superficial- and deep-posterior compartments. The anterior compartment includes the tibialis anterior, the extensor hallucis longus, the extensor digitorum longus, and the fibularis (peroneus) tertius. The lateral compartment houses the fibularis (peroneus) longus and the fibularis (peroneus) brevis. The superficial posterior compartment has the gastrocnemius, soleus, and plantaris; and the deep posterior compartment has the popliteus, tibialis posterior, flexor digitorum longus, and flexor hallucis longus.

Glossary

adductor brevis

muscle that adducts and medially rotates the thigh

adductor longus

muscle that adducts, medially rotates, and flexes the thigh

adductor magnus

muscle with an anterior fascicle that adducts, medially rotates and flexes the thigh, and a posterior fascicle that assists in thigh extension

anterior compartment of the leg

region that includes muscles that dorsiflex the foot

anterior compartment of the thigh

region that includes muscles that flex the thigh and extend the leg

biceps femoris

hamstring muscle

calcaneal tendon

(also, Achilles tendon) strong tendon that inserts into the calcaneal bone of the ankle

dorsal group

region that includes the extensor digitorum brevis

extensor digitorum brevis

muscle that extends the toes

extensor digitorum longus

muscle that is lateral to the tibialis anterior

extensor hallucis longus

muscle that is partly deep to the tibialis anterior and extensor digitorum longus

femoral triangle

region formed at the junction between the hip and the leg and includes the pectineus, femoral nerve, femoral artery, femoral vein, and deep inguinal lymph nodes

fibularis brevis

(also, peroneus brevis) muscle that plantar flexes the foot at the ankle and everts it at the intertarsal joints

fibularis longus

(also, peroneus longus) muscle that plantar flexes the foot at the ankle and everts it at the intertarsal joints

fibularis tertius

small muscle that is associated with the extensor digitorum longus

flexor digitorum longus

muscle that flexes the four small toes

flexor hallucis longus

muscle that flexes the big toe

gastrocnemius

most superficial muscle of the calf

gluteal group

muscle group that extends, flexes, rotates, adducts, and abducts the femur

gluteus maximus

largest of the gluteus muscles that extends the femur

gluteus medius

muscle deep to the gluteus maximus that abducts the femur at the hip

gluteus minimus

smallest of the gluteal muscles and deep to the gluteus medius

gracilis

muscle that adducts the thigh and flexes the leg at the knee

hamstring group

three long muscles on the back of the leg

iliacus

muscle that, along with the psoas major, makes up the iliopsoas

iliopsoas group

muscle group consisting of iliacus and psoas major muscles, that flexes the thigh at the hip, rotates it laterally, and flexes the trunk of the body onto the hip

iliotibial tract

muscle that inserts onto the tibia; made up of the gluteus maximus and connective tissues of the tensor fasciae latae

inferior extensor retinaculum

cruciate ligament of the ankle

inferior gemellus

muscle deep to the gluteus maximus on the lateral surface of the thigh that laterally rotates the femur at the hip

lateral compartment of the leg

region that includes the fibularis (peroneus) longus and the fibularis (peroneus) brevis and their associated blood vessels and nerves

medial compartment of the thigh

a region that includes the adductor longus, adductor brevis, adductor magnus, pectineus, gracilis, and their associated blood vessels and nerves

obturator externus

muscle deep to the gluteus maximus on the lateral surface of the thigh that laterally rotates the femur at the hip

obturator internus

muscle deep to the gluteus maximus on the lateral surface of the thigh that laterally rotates the femur at the hip

patellar ligament

extension of the quadriceps tendon below the patella

pectineus

muscle that abducts and flexes the femur at the hip

pelvic girdle

hips, a foundation for the lower limb

piriformis

muscle deep to the gluteus maximus on the lateral surface of the thigh that laterally rotates the femur at the hip

plantar aponeurosis

muscle that supports the longitudinal arch of the foot

plantar group

four-layered group of intrinsic foot muscles

plantaris

muscle that runs obliquely between the gastrocnemius and the soleus

popliteal fossa

diamond-shaped space at the back of the knee

popliteus

muscle that flexes the leg at the knee and creates the floor of the popliteal fossa

posterior compartment of the leg

region that includes the superficial gastrocnemius, soleus, and plantaris, and the deep popliteus, flexor digitorum longus, flexor hallucis longus, and tibialis posterior

posterior compartment of the thigh

region that includes muscles that flex the leg and extend the thigh

psoas major

muscle that, along with the iliacus, makes up the iliopsoas

quadratus femoris

muscle deep to the gluteus maximus on the lateral surface of the thigh that laterally rotates the femur at the hip

quadriceps femoris group

four muscles, that extend and stabilize the knee

quadriceps tendon

(also, patellar tendon) tendon common to all four quadriceps muscles, inserts into the patella

rectus femoris

quadricep muscle on the anterior aspect of the thigh

sartorius

band-like muscle that flexes, abducts, and laterally rotates the leg at the hip

semimembranosus

hamstring muscle

semitendinosus

hamstring muscle

soleus

wide, flat muscle deep to the gastrocnemius

superior extensor retinaculum

transverse ligament of the ankle

superior gemellus

muscle deep to the gluteus maximus on the lateral surface of the thigh that laterally rotates the femur at the hip

tensor fascia lata

muscle that flexes and abducts the thigh

tibialis anterior

muscle located on the lateral surface of the tibia

tibialis posterior

muscle that plantar flexes and inverts the foot

vastus intermedius

quadricep muscle that is between the vastus lateralis and vastus medialis and is deep to the rectus femoris

vastus lateralis

quadricep muscle on the lateral aspect of the thigh

vastus medialis

quadricep muscle on the medial aspect of the thigh

REVIEW QUESTIONS

CRITICAL THINKING QUESTIONS