Muscles of the Pelvis and Lower Limbs

Muscles of the pelvis and lower limb Three functional groups Muscles that work across the hip joint; move the thigh Muscles that work across the knee joint; move the leg Muscles that work across the joints of the foot; move the ankle

Muscles that move the thigh Gluteal muscles Adductors Hip flexors ALL have insertions on the femur and therefore cause movement of thigh

Gluteal muscles Cover the lateral surface of the ilia Actions: extension, rotation, abduction at the hip Gluteus maximus = largest and most posterior Gluteus minimus = smallest; deep Gluteus medius = intermediate medius maximus medius minimus

Adductors Actions: adduction Muscle strain = pulled groin Pectineus Adductor brevis= shortest Adductor longus= longest Adductor magnus= largest Gracilis

Pectineus brevis longus magnus gracilis

Iliopsoas Actions: hip flexion Two muscles Psoas major Iliacus

psoas iliacus Pectineus brevis longus magnus gracilis

Muscles that move the leg

Muscles that move the leg Hamstrings (3 muscles) Quadriceps (4 muscles) Sartorius ALL have insertions on the tibia and fibula and therefore cause movement of the leg

Hamstrings Action: knee flexion Three muscles Biceps femoris (lateral) Semitendinosus (midline) Semimembranosus (medial)

semitendinosus Biceps femoris semimebranosus Gluteus maximus Add. magnus semitendinosus gracilis Biceps femoris semimebranosus

Quadriceps Action: extension of knee Four muscles Rectus femoris Vastus lateralis = lateral Vastus medialis = medial Vastus intermedius = deep

Rectus femoris v. lateralis V. medialis iliopsoas pectineus Add. longus gracilis Rectus femoris v. lateralis V. medialis

Sartorius Action: hip flexion AND knee flexion Assists the hamstrings

sartorius sartorius iliopsoas pectineus Add. longus gracilis Gluteus maximus pectineus Add. longus gracilis Add. magnus sartorius semitendinosus Rectus femoris v. lateralis gracilis V. medialis Biceps femoris semimebranosus sartorius

Muscles that move the foot

Muscles that move the foot Tibialis anterior Gastrocnemius Soleus Fibularis ALL have insertions on the tarsals and metatarsals and therefore cause movement of the foot

Tibialis anterior Action: dorsiflexion Microtears associated with “shin splints”

Gastrocnemius (“stomach” “knee”) Calf muscle Action: plantar flexion

Soleus Action: plantar flexion Gastrocnemius and soleus share a common tendon, the Achilles tendon

Fibularis Actions: plantar flexion and eversion Fibularis Tibialis anterior

gastrocnemius soleus