Skip to content

Serratus anterior



Serratus anterior - anterior view
Serratus anterior - lateral view
Serratus anterior - posterolateral view
Serratus anterior - anteromedial view

General information

  • This section is strictly limited to anatomy, you might be looking for clinical relevant information which is found under the clinical chapters -- muscles section, click here to go to that page


  • Deep


  • 1-9th ribs
    • Anterolateral aspect


  • Anterior aspect of medial limitatoin of scapula

Main function

  • Scapula
    • Protraction
    • Upward rotation
    • Lateral rotation of lower part

Secondary function

  • Scapula
    • Elevation
    • Depression

Nerve innervation

  • Segmental
    • C5-C7
  • Peripheral
    • Long thoracic nerve

Arterial supply

  • Dorsal scapular artery


  • Patient position
    • Supine
  • Patient is holding the arm flexed in a 90° position of the shoulder
  • Palpate the lateral limitation of the pectoralis major muscle, and from that position localize the lateral limitation of latissimus dorsi
  • Palpate the area between these two muscle in the axilla, while you feel for the ribs and serratus anterior
  • Have the patient protract the scapula to feel for the contraction of the serratus anterior

Muscle length test

  • Patient position
    • Sitting or standing
  • Ask the patient to lift the arm so that it is flexed to a 120° angle of the shoulder
  • Consider if the patient's scapula is showing sufficent abduction (lateral rotation of inferior angle) in this position
  • If there is not a sufficient abduction (lateral rotation) of the scapula in this positioin, have the patient rest their arm on the therapist's shoulder in the same position
  • Pull the scapula forward and into normal position again
  • The patient is then holding the arm in the same position
    • If the scapula is pulled back into adduction it is probable that there is a shortening of the serratus anterior

Strength test

  • Patient position
    • Supine
  • Ask the patient to hold the arm straight in front of the body -  90° flexion of the shoulder joint
  • Ask the patient to form a fist
  • Give resistance towards the patient's fist so that the have to press the arm upwards and the scapula is protracted