Where Is the Deltoid?
What are the Symptoms of Deltoid Tear or Deltoid Strain?
It mat be hard to lift the arm if the deltoid has been hurt. Usually deeper muscles are responsible for pain in the shoulder such as the Supraspinatus or other rotator cuff muscles.
What is The Function of the Deltoid?
The deltoid muscle lifts the arm away from the body with it's middle part. (Abducts the arm)
The front and back part of the arm also help to lift the arm away from the body.
The front part of the Deltoid lifts the arm forward. (Flexion at the shoulder)
The front of the arm also helps with internal rotation.
The back of (posterior) part of the arm helps lift the arm backwards (extension of the arm at the shoulder) and helps externally rotate the arm.
Origin and Insertion of Deltoid
Lateral third of the clavicle, acromion, the lower partof the spine of the scapula.
Deltoid tuberosity of the humerus (Arm bone)