shoulder blade

Synonyms

Medical: scapula

Shoulder blade, scapula, scapula

English: shoulder blade

anatomy

The shoulder blade (scapula) is a flat, triangular bone and the connection between the upper extremity and the trunk. The back of the shoulder blade is divided by a bony ridge (spina scapulae), which ends in a bony protrusion (acromion) towards the front. The acromion, together with the collarbone (clavicle), forms the shoulder joint (acromion - clavicular joint / AC joint). Another important extension of the shoulder blade is the coracoid / coracoid. This ends below the acromion and is an important starting point for muscles and ligaments for the stability and function of the shoulder joint and shoulder joint.

On the side of the shoulder blade is the joint-forming structure and abutment Humerus head the shoulder joint socket (glenoid).

The shoulder blade also serves towards the Rotator cuff as a bony origin. A rotator cuff is a muscular unit that is of particular importance for movement, especially the rotation of the arm. Many other muscles flexibly fix the shoulder blade to the trunk.

Figure shoulder blade

Right shoulder blade from behind (above) and from the front (below)
  1. Upper edge -
    Margo superior
  2. Outer edge -
    Margo lateralis
  3. Inner edge -
    Margo medialis
  4. Upper angle -
    Angulus superior
  5. Lower angle -
    Angulus inferior
  6. Shoulder joint socket -
    Glenoid Cavitas
  7. Scapula bone -
    Spina scapulae
  8. Shoulder corner -
    Acromion
  9. Raven beak process -
    Coracoid process
  10. Rib area -
    Facies costalis
  11. Upper bone pit -
    Supraspinous fossa
  12. Underbone Pit -
    Infraspinate fossa

You can find an overview of all Dr-Gumpert images at: medical illustrations

Muscles that attach to the shoulder blade:
Back:

  • Levator scapulae muscle
  • Rhomboideus major muscle
  • Latissimus dorsi muscle
  • Trapezius muscle
  • Supraspinatus muscle
  • Infraspinatus muscle

Front:

  • Pectoralis minor muscle (Coracoid)
  • Biceps brachii muscle (Coracoid, short biceps tendon)
  • Subscapularis muscle
  • Deltoid muscle

Figure shoulder blade

  1. Cervical spine (cervical spine)
  2. Rib / rib cage
  3. shoulder blade
  4. Humerus (Humerus)
  5. Pelvis
  6. Sacrum (sacrum)
  7. Lumbar spine (lumbar spine)
  8. Thoracic spine

function

The shoulder blade is the origin of many muscles and is of great importance for the movement and suspension of the arm. A movement of the arm in the Shoulder joint alone is only possible up to approximately horizontal. If you move beyond that, the shoulder blade rotates inwards.

Diseases of the shoulder joint

Diseases of the shoulder blade itself are rare. Sometimes a serious fall on the back leads to a fracture of the shoulder blade, which usually has to be treated conservatively (not surgically). In extreme cases, for example after rapid trauma in the context of car accidents, the shoulder blade neck and collarbone may fracture at the same time. The result is an unstable shoulder suspension and the need for surgical intervention.

Leading diseases of the shoulder blade, however, are diseases of the attaching muscles and ligaments (biceps muscles, rotator cuff, shoulder joint). The most well-known and frequently occurring diseases are the impingement syndrome and the rotator cuff tear.

In the event of an injury to the internal thoracic nerve, paralysis of the serratus anterius muscle, with typical protrusion of the shoulder blade (scapula alata), results in a stabilizing effect on the shoulder blade.

Read more about the Scapula alata here