Download Muscles of the upper and lower limbs

Muscles of the upper and
lower limbs
Appendicular Muscles
Upper limb muscles have 3 major
groups
Lower limb muscles are the largest
Upper limb Muscles
• 3 groups
– The first group arises from the shoulder girdle and
insert into the humerus
– The second group encloses the humerus and insert
into the forearm bones causing movement at the
elbow joint
– The third group is the muscles of the forearm which
insert into the hand and wrist
Upper limb Muscles
• Group 1
– Already discussed
• Pectoralis major
• Latissimus dorsi
• Dletoid
• Group 2
– Biceps brachii
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Most familiar muscle
Two origin in the shoulder girdle
Inserts into the radial tuberosity
Prime mover of the forearm flexion and supinates the forearm
Upper limb Muscles
• Group 2
– Brachialis
• Deep to the biceps muscle and is a synergist to the biceps
muscle in forearm movement
– Brachioradialis
• Weak muscle
• Arises on the humerus
• Inserts into the distal forearm
Upper limb muscles
• Group 2
– Triceps brachii
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Only posterior muscle on the humerus
Has 3 heads
Origin in the shoulder girdle and proximal humerus
Inserts into the olecranon process of the ulna
Extends the forearm at the elbow
Upper limb muscles
• Group 3
– Supinator muscle
• Under the upper posterior portion of the radius
• Works synergistically with the biceps brachii to supinate
the hand
– Pronator teres
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Located on the upper medial side of the forearm
Origin is in the medial epicondyle of the humerus
Inserts on the upper lateral shaft of the radius
Pronates the hand
Upper limb muscles
• Group 3
– Pronator quadratus
• Extends between the ulna and the radius
• Origin is on the ulna, inserts on the radius
• Works synergistic with the pronator teres and rotates the
palm
Lower limb muscles

Divided into 3 groups
 Movement
of the hip
 Movement of the knee
 Movement of the foot
Lower limb muscles

Group 1
 Gluteus
maximus
Superficial muscle of the hip
 Forms the buttock
 Hip extensor
 Not important in walking, but is important when
power is needed for climbing
 Origin is in the sacrum and iliac
 Inserts into the gluteal tuberosity of the femur

Lower limb muscles
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Group 1
 Gluteus
medius
Runs from the ilium to the femur
 Beneath the gluteus maximus
 Hip abductor
 Steadies the plevis during walking
 Used for injections

Lower limb muscles
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Group 1
 iliopsoas

Fused muscle
Iliacus
 Psoas major

Prime mover of the hip flexion
 Keeps the upper body from falling backwards

Lower limb muscles

Group 1
 Adductor
muscles
Group of muscles
 Medial side of each thigh
 Press the thighs together

Lower limb muscles

Group 2
 Muscles

causing movement at the knee joint
Quadriceps group

Sartorius – obliquely crosses the anterior aspect of the
thigh. It arises from the anterior superior spine of the
ilium and extends medially to insert into the proximal
medial surface of the tibia
 Acts on the hip and knee joints
Lower limb muscles

Group 2
 Quadriceps
femoris – composite of 4 distinct
muscles
Have separate origins, but a common insertion via
the patella tendon
 Function synergistically to extend the leg


Rectus femoris – occupies a superficial position,
functions with both the hip and the knee
Lower limb muscles

Group 2
 Vastus lateralis – the largest muscle of the quadriceps
femoris, extends the knee
 Vastus medialis – occupies the medial position along the
thigh, extends the knee
 Vastus intermedius – lies deep to the previous 2 muscles,
extends the knee
 Muscles

of the hamstring group
Biceps femoris – occupies the posterior lateral aspect of the
thigh, flexes the knee and moves the hip joint. It has a
superficial long head and a deep short head
Lower limb muscles

Group 2
 Muscles

Semitendinosus – is a fusiform muscle and is
located on the posterior medial aspect of the thigh


of the hamstring group
Works over 2 joints, the medial rotation of the leg (hip)
and flexion of the lower leg
Semimembranous – is deep to the
semitendinosus, synergistic to the semitendinosus
Lower limb muscles

Group 3
 Muscles

that move the foot (crural muscles)
3 groups of crural muscles
Anterior crural muscles – tibialis anterior, extensor
digitorum longus, extensor hallucis longus, and peroneus
tertius
 Lateral crural muscles – peroneus longus, peroneus
brevis
 Posterior crural muscles – gastrocnemius, soleus [triceps
surae], plantaris, popliteus, flexor hallucis longus, flexor
digitorum longus, and tibialis posterior
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