Shoulder / Arm

Shoulder Pain in Acromioclavicular Joint Disorders

Definition

Osteoarthritis and distortion of the acromioclavicular (AC) joint result in inflammation of the joint and joint capsule, and is one of the frequently seen shoulder pains in general practice.

Aetiology

The cause of a disorder of the AC joint is, apart from direct or indirect trauma of the joint as seen in WAD patients, is usually degenerative in origin.

Segmental dysfunction of the cervical spine and cervicothoracic junction can play a role in the clinical picture. Therefore, it is very important, in addition to evaluation of shoulder function, to examine the cervical spine as well.

Signs and symptoms

In general, the symptoms are characterised by shoulder pain that increases after each time it takes a load, with shoulder abduction of over 90°. Nocturnal pain and the inability to sleep on the affected shoulder point in the direction of an inflammation.

The location and radiation pattern of the pain can provide information on whether it is caused by a primary pathology of the shoulder, or that it is located outside the shoulder.

In particular, in non-traumatic shoulder pain with an abnormal natural course, other serious diseases, such as generalised joint pain, fever, malaise, weight loss, dyspnoea and angina pectoris, should be explored. Most importantly, a pancoast tumour must be excluded.

Diagnostics

Physical Examination

Examination of the shoulder in AC disorders:

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.

The table below lists the various shoulder disorders, including those with a passive external rotation restriction.

 

DISORDER

Passive External Rotation restriction

Active Abduction restriction
in
Neutral Position Arm

Passive Abduction restriction
in
External Rotation Position Arm

Passive Horizontal Abduction restriction

Osteoarthritis Glenohumeral Joint

+++

+++

+++

+

Capsulitis Glenohumeral Joint

+++

+++

+++

+

Rotator Cuff Syndrome

++

+++

+++

+

Osteoarthritis Acromioclavicular Joint

-

+++

+++

+++

Additional Somatic Diagnostics

  • In the initial phase of uncomplicated shoulder complaints, no imaging techniques or laboratory examinations are indicated.
  • If systemic diseases or other serious conditions are suspected in shoulder pain, blood tests are indicated (CRP, Hb, BSE, rheumatoid factors).
  • When shoulder pain persists, X-ray, ultrasound and MRI scan are indicated.
  • A bone scan is indicated if there is any suspicion of metastases or primary tumours.

Somatic Treatment

Pharmacological treatment:

Other Treatments

Interventional Pain Treatment

When the injection is performed correctly,  pain-free passive shoulder abduction should be present immediately following this injection.
When the effect is only temporary, referral to an orthopedic surgeon is indicated.