Anatomy
The shoulder joint (= Articulatio humeri) is located between the head of the humerus and the glenoid cavity of the shoulder blade. Due to the shape of the joint, it is one of the most flexible joints of the entire body. This form of the joints is called: BALL JOINTS.
The relatively large range of motion of the shoulder joint is due to its anatomy. For example, the glenoid cavity of the shoulder is quite small compared to the head of the humerus. In addition, muscles and joint capsules have a wide range of movement due to their relatively loose tension.
At first glance, a relatively large range of motion does not appear to have any disadvantages. The greater the freedom of movement, the more possibilities of movement the person has. However, if traumatic events occur or if individual (congenital) causes are present, the easier it is to develop an “atraumatic” (habitual) dislocation.
- Humeral head (humerus)
- Shoulder height (Acromion)
- Shoulder corner joint
- Collarbone (Clavicle)
- Coracoid
- Shoulder joint (glenohumeral joint)
Classification
Since there are different forms of shoulder dislocation, we try to classify them as comprehensibly as possible. So far there is no generally valid form of classification. It is described by means of the cause and direction of the dislocation, as well as its shape and degree. The following criteria are used in combination to describe the dislocation. Pathogenesis (cause): localization of the shoulder dislocation: severity of the shoulder dislocation:
- Traumatic unidirectional
- Unidirectional
- Atraumatic
- The following forms of dislocation can occur in the context of an atraumatic shoulder dislocation: Habitually unidirectional Habitually arbitrary Habitually multidirectional
- Habitually unidirectional
- Habitually arbitrary
- Habitually multidirectional
- Unidirectional
- Habitually unidirectional
- Habitually arbitrary
- Habitually multidirectional
- Anterior-inferior (front-bottom) = Luxatio subcoracoidea
- Posterior-superior (back-up)
- Combinations
- Grade I (Distortion): Elongation Capsule and musculature are intact Some fiber tears are present
- Elongation
- Capsule and musculature are intact
- Some fiber cracks can be found
- Grade II (subluxation): Partial muscle lesion Capsule rupture or capsule detachment
- Partial muscle lesion
- Capsule rupture, or capsule detachment
- Grade III (dislocation): Capsule- ligament lesions are always present Usually the dislocation is anterior (in about 96% of all cases)
- Capsule- ligament lesions are always present
- As a rule, dislocation occurs forward (in about 96% of all cases)
- Elongation
- Capsule and musculature are intact
- Some fiber cracks can be found
- Partial muscle lesion
- Capsule rupture, or capsule detachment
- Capsule- ligament lesions are always present
- As a rule, dislocation occurs forward (in about 96% of all cases)