Key Muscle Locations and Movements
What muscles cause certain movements?
Given that muscles make movement happen, each muscle will create a certain movement around a joint. For instance the quadriceps muscle group will extend the knee and flex the hip. The tables on the following pages detail the origin, insertion and action of some of the major muscles in the body. Use these tables in conjunction with the muscle charts on (in this same folder at ptdirect) to help you locate and understand how these muscles create movement.
Major muscles of the back, shoulder and chest:
|
Muscle |
Origin |
Insertion |
Movement/Action |
|
Erector spinae |
|
Upper thoracic vertebrae and the cervical vertebrae
|
Extension of the vertebral column |
|
Latissimus dorsi |
Thoracic, lumbar vertebrae, sacrum and top of pelvis
|
Upper part of humerus
|
Adduction, extention and medial rotation of the arm. Retraction and depression of shoulder |
|
Trapezius |
Cervical and thoracic vertebrae, base of skull
|
Clavicle and scapula
|
Elevation, depression and retraction of the scapula |
|
Rhomboids |
C7-T5 vertebrae
|
Medial border of the scapula
|
Retraction and depression of the scapula. Fixes the scapula to the thoracic wall
|
|
Deltoid |
Clavicle and spine of scapula
|
Upper part of humerus
|
Abduction, extension, lateral rotation, flexion and medial rotation of arm
|
|
Pectoralis major |
Sternum, clavicle and 1st-6th ribs
|
Upper front area of humerus
|
Adduction, flexion and medial rotation of arm |
Major muscles of the upper arm:
|
Muscle |
Origin |
Insertion |
Movement/Action |
|
Biceps brachii |
Scapula |
Radius |
Flexion of elbow and supination of forearm |
|
Triceps brachii |
Scapula and upper part of humerus |
Ulna |
Extension of elbow |
Major muscles of the Abdomen:
|
Muscle |
Origin |
Insertion |
Movement/Action |
|
Rectus abdominus |
Front lower part of pelvis |
5th, 6th and 7th ribs and lowest part of sternum |
Flexion of vertebral column |
|
External oblique’s |
Lower ribs |
Front upper part of pelvis |
Rotation of vertebral column, compression of abdomen and flexion of vertebral column |
|
Internal oblique’s |
Top of pelvis |
Lower three ribs |
Compression of abdomen, flexion of vertebral column and rotation of vertebral column |
Major muscles of the hip region:
|
Muscle |
Origin |
Insertion |
Movement/Action |
|
Gluteus maximus |
Rear part of pelvis, sacrum and coccyx |
Top of femur |
Extension and lateral rotation of leg |
|
Gluteus medius |
Upper part of pelvis |
Outside of upper part of femur |
Abduction and medial rotation of leg |
|
Gluteus minimus |
Mid outer surface of pelvis |
Outside of upper part of femur |
Abduction and medial rotation of leg |
|
Hip flexors (Psoas major and Ilicus) |
Lumbar vertebrae and top of pelvis |
Upper part of femur |
Flexion of femur and vertebral column. Flexion and lateral rotation of leg |
Muscles of the quadriceps:
Muscles of the hamstrings:
|
Muscle |
Origin |
Insertion |
Movement/Action |
|
Hamstrings (Semimembranosus, Semitendinosus, Biceps femoris) |
Lower back part of pelvis and femur |
Upper part of tibia and fibula |
Extension, medial and lateral rotation of leg. Flexion of knee |
Muscles of the calves:
|
Muscle |
Origin |
Insertion |
Movement/Action |
|
Gastrocnemius |
Lower rear part of femur |
Heel bone |
Plantar flexion of foot and flexion of knee |
|
Soleus |
Upper rear part of tibia and fibula
|
Heel bone |
Plantar flexion of foot |
