Shoulder instability is increased mobility of the glenohumeral joint due to hyperlaxity of the joint capsule.
Shoulder instability may be congenital or post-traumatic in origin. Hypermobility frequently plays a role. The relationship with connective tissue disorders, such as Ehler-Danlos, and ligament hypermobility syndromes is not clear yet.
Segmental dysfunction of the cervical spine and cervicothoracic junction can play a role in the clinical picture. Therefore, in addition to the evaluation of shoulder function, it is very important to examine the cervical spine as well.
Signs and symptoms
Anamnestically, in the vast majority of cases, there are indications of (sub)luxation of the shoulder due to its taking normal loads. Sometimes transient paraesthesia in arm and hand are present (traction paraesthesia).
Examination of the shoulder in shoulder instability:
Three groups of shoulder tests are important in examination of the shoulder: 1. active and passive shoulder abduction; 2. active and passive shoulder external rotation; and 3. active and passive horizontal shoulder adduction. Serious shoulder pathology, presenting as brachialgia, can be diagnosed by means of these tests.
In addition, it is important to perform passive shoulder abduction in external rotation. Passive abduction should be performed as often as possible in the frontal plane.
When shoulder instability is suspected, besides extremities such as the elbow (hyperextension of the elbow >180o), the acromioclavicular and sternoclavicular joints must be examined for hypermobility. Shoulder instability is evaluated by the examination of passive mobility in various directions.
Additional Somatic Diagnostics
- In the initial phase of uncomplicated shoulder complaints, no imaging techniques or laboratory examinations are indicated.
- In a later phase, X-rays are indicated to show osseous abnormalities of the head of the humeral and glenoid cavity.
- MRI scan of the shoulder can provide more information on the consequences of reoccurring (sub)luxations.
- Non-steroid Anti-inflammatories (short period)
Interventional Pain Treatment