Anatomy

• 3 bones in the shoulder region:

  • Clavicle
  • Humerus
  • Scapula
• 3 important parts to the scapula:

  • Acromion
  • Coracoid process
  • Glenoid fossa
• Joints formed by the clavicle, humerus and scapula:

  • Acromioclavicular joint - between the acromion of the scapula and the clavicle
  • Glenohumeral joint - between glenoid fossa of the scapula and the humerus
• Rotator cuff muscles (SITS):

  • Supraspinatus - abduction (first 15 degrees)
  • Infraspinatus - external rotation
  • Teres minor - external rotation and adduction
  • Subscapularis - internal rotation
• Shoulder abduction:

  • 0-15 degrees: supraspinatus
  • 15-90 degrees: deltoid
  • >90 degrees: trapezius and serratus anterior
• Subacromial space:

  • Important space underneath the acromion that tendons pass through
• The rotator cuff is a group of muscles and tendons around the shoulder joint, keeping the head of the humerus firmly within the glenoid fossa of the scapula