1. Muscles of the Forearm and Lower Leg

2. Muscles of the Forearm Posterior extensors: Anterior flexors:
Extensor carpi radialis longus
Extensor digitorum
Extensor carpi ulnaris
Anterior flexors:
Flexor carpi radialis
Flexor carpi ulnaris
Flexor digitorum
Palmaris longus

3. Brachioradialis
origin: lateral epicondyle
of humerus.
insertion: styloid of radius.
action: synergist in forearm flexion.
Ext. carpi radialis longus
origin: later epicondyle of humerus.
insertion: metacarpals.
action: extends wrist.

4. Extensor carpi ulnaris
origin: Lateral epicondyle
of humerus.
insertion: metacarpals.
action: extends wrist.
Extensor digitorum
insertion: phalanges.
action: extends fingers 2-5.

6. Palmaris longus
origin: medial epicondyle of humerus.
insertion: fascia of palm.
action: "squeezes palm".
Flex. carpi ulnaris
origin: medial epicondyle
of humerus.
insertion: metacarpals.
action: flexes wrist.
Flex. carpi radialis

7. Retinacula Flexor digitorm origin: medial epicondyle of humerus.
insertion: phalanges.
action: flexes fingers 2-5.
Retinacula

8. Posterior compartment:
-Gastrocnemius
-Soleus

9. Muscle:
Origin:
Insertion:
Action
Gastrocnemius
Lateral and medial femoral condyles.
Calcaneus via the “Achilles ” tendon
Plantar flexion of foot.
Soleus
Head and shaft of fibula.
Calcaneus via the “Achilles” tendon

10. Anterior/lateral compartments:
-Tibialis anterior
-Extensor digitorum longus
-Fibularis longus

11. Muscle:
Origin:
Insertion:
Action:
Tibialis anterior
Lateral condyle of tibia.
First metatarsal and cuneiform bone.
Dorsiflexion and inversion of foot.
Extensor digitorum longus
Toes (phalanges) 2 thru 5.
Extension of toes 2 thru 5.
Fibularis longus
Lateral condyle of tibia and fibula head and shaft.
Plantar flexion and eversion of foot .

12. Compartment Syndrome: increased pressure in a muscle compartment