Synonyms
Medical: scapula shoulder blade, scapula, scapula
Anatomy
The shoulder blade (scapula) is a flat, triangular bone and the connection between the upper extremity and the trunk. The shoulder blade is divided at the back by a bony groin (Spina scapulae), which ends in a bony protrusion (acromion) at the front. Together with the clavicle, the acromion forms the acromioclavicular joint (acromio – clavicular jointAC 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 acromioclavicular joint and shoulder joint. The glenoid cavity is located on the side of the scapula as a joint-forming structure and abutment of the humeral head.
The shoulder blade also serves as a bony origin towards the rotator cuff. The rotator cuff is a muscular unit that is of particular importance for movement, especially the rotation of the arm. Many other muscles fix the shoulder blade flexibly to the trunk. Muscles that attach to the shoulder blade:Back: Front:
- Musculus levator scapulae
- Musculus rhomboideus major
- Musculus latissimus dorsi
- Musculus trapezius
- Musculus supraspinatus
- Musculus infraspinatus
- Musculus pectoralis minor (Coracoid)
- Musculus biceps brachii (Coracoid, short biceps tendon)
- Subscapular Musculus
- Deltoid muscle
- Cervical spine (HWS)
- Rib Chest Basket
- Shoulder blade
- Humerus (upper arm bone)
- Pelvis (pelvis)
- Sacrum (Os sacrum)
- Lumbar Spine (LWS)
- 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. Movement of the arm in the shoulder joint alone is only possible up to approximately horizontal. Movements beyond this point cause the shoulder blade to rotate inwards.
Diseases of the shoulder cuff
Diseases of the shoulder blade itself are rare. Sometimes a severe fall on the back causes a fracture of the shoulder blade, which usually has to be treated conservatively (not surgically). In extreme cases, for example after speeding accidents, the neck of the shoulder blade and the collarbone can be fractured at the same time.
The result is unstable shoulder suspension and the need for surgical intervention. However, the leading diseases of the shoulder blade are diseases of the attaching muscles and ligament apparatus (biceps muscle, rotator cuff, acromioclavicular joint). The best known and most common clinical pictures are the impingement syndrome and rotator cuff tear. Injury to the internal thoracic nerve results in paralysis of the serratus anterius muscle stabilizing the scapula, with typical scapular protrusion (scapula alata).
