Chapter 12

Appendicular muscles

Upper limb muscles to know and identify

• Shoulder: Deltoid (sometimes referred as axial muscle).

• Upper arm (brachium): Biceps brachii, Triceps brachii, Brachialis, Brachioradialis

Upper arm

Forearm muscles

Lower limb muscles to know and identify

• Upper leg: Sartorius, Tensor fasciae latae, Adductor longus, Adductor magnus, Gracilis, Rectus femoris, Vastus lateralis, Vastus medialis, Biceps femoris, Semitendinosus, Semimembranosis.

• Lower leg and calf: Tibialis anterior, Gastrocnemius, Soleus

Quadriceps femoris group

• Rectus femoris• Vastus medialis• Vastus lateralis• Vastus intermedius

Hamstring muscle group

• Biceps femoris• Semimembranosis• Semitendonosis

Muscles of lower leg

Appendicular muscles to know origin and insertion

• Biceps brachii - Rectus femoris• Triceps brachii - Biceps femoris• Sartorius - Deltoid

- Gastrocnemeus

Biceps brachii• Origin: SH coracoid process; LH supraglenoid

tubercle• Insertion: Radial tuberosity• Action: flex elbow and shoulder

Triceps brachii• Origin: Lat H: Sup, lateral margin of humerus; LH:

Infraglenoid tubercle; Med H: Post humerus• Insertion: Olecranon of ulna• Action: Extension at elbow

Deltoid• Origin: Clavicle, scapula acromion and spine• Insertion: Deltoid tuberosity of humerus• Action: Abducts shoulder; flexion and rotation of

humerus; extension and lateral rotation of humerus

Rectus femoris (Quads)• Origin: Ant iliac spine and sup. margin acetabulum• Insertion: Patella and tibial tuberosity• Action: Extension of leg at knee; flex thigh at hip

Sartorius• Origin: Ant, superior spine of ilium• Insertion: Medial aspect tibial tuberosity• Action: Flexes, abducts and laterally rotates thigh at

hip; flexes knee

Biceps femoris (Hamstrings)

• Origin: LH: ischial tuberosity; SH: linea aspera of femur

• Insertion: Head of fibula • Action: Flexes knee;

extends hip; laterally rotates leg

Gastrocnemius

• Origin: Lateral condyle and popliteal surface of femur

• Insertion: Calcaneus via achilles tendon

• Action: Flexes knee and plantar flexion of foot

Structures to know and identify

• Tendons• Galea aponeurosis• Linea alba• Iliotibial tract• Calcaneal “achiles” tendon