++
Search for clues—difficulty reaching into the hip pocket to remove a wallet may indicate loss of function due to total rupture of the supraspinatus tendon, while a complete rotator-cuff tear may lead the patient to lift the affected limb to the clothes line and leave it suspended there by the hand while hanging out the laundry.
MICHAEL HAYES 1996
++
The painful shoulder is a relatively common and sometimes complex problem encountered in general practice. The diagnostic approach involves determining whether the disorder causing the pain arises from within the shoulder structures or from other sources such as the cervical spine (see FIG. 52.1), the acromioclavicular (AC) joint or diseased viscera, especially the heart, lungs and sub-diaphragmatic structures.
++++
Note: The term tendinopathy or tendinosis is preferred to tendinitis since it has been shown that overuse tendon conditions generally have a non-inflammatory pathology.
++
Key facts and checkpoints
Virtually all shoulder structures are innervated by the fifth cervical vertebra (C5) nerve root. Pain present in the distribution of the C5 nerve can arise from the:
cervical spine
upper roots of brachial plexus
acromioclavicular joint
glenohumeral joint
rotator cuff tendons, especially supraspinatus
biceps tendon
soft tissue (e.g. polymyalgia rheumatica)
viscera, especially those innervated by the phrenic nerve (C3, C4, C5)
The visceral diseases causing a painful shoulder include cardiac disorders, such as angina and pericarditis; lung diseases, especially Pancoast tumour; mediastinal disorders; and diaphragmatic irritation, as from intra-abdominal bleeding or a subphrenic abscess.
A careful history should generally indicate whether the neck or the shoulder is responsible for the pain.
By the age of 50, about 25% of people have some wear and tear of the rotator cuff, making it more injury-prone.1
Disorders of the rotator cuff are common, especially supraspinatus tendinopathy. The most effective tests to diagnose these problems are the resisted movement tests.1
Injections of local anaesthetic and long-acting corticosteroid produce excellent results for inflammatory disorders around the shoulder joint, especially for supraspinatus tendinopathy. They are simple to perform and do not require ultrasound guidance.
The diagnosis is usually made on the history and examination. Blood tests are usually not necessary and imaging has a limited place and value.2
+++
FUNCTIONAL ANATOMY OF THE SHOULDER
++
A working knowledge of the anatomical features of the shoulder is essential for understanding the various disorders causing pain or dysfunction of the shoulder. Apart from the AC joint (ACJ) there are two most significant functional joints—the glenohumeral (the primary joint) and the subacromial complex (the secondary joint) (see FIG. 52.2). The glenohumeral joint is a ball and socket joint enveloped by a loose capsule. It is prone to injury from traumatic ...