A 45-year-old woman presents to the GP with pain in her left shoulder. She says this has been going on for the past 3 weeks and is limiting her ability to work. She works for a food packaging company and has to move heavy boxes and stack tall shelves as part of her job. She has no significant past medical history. On examination, there is tenderness at the anterolateral aspect of her left shoulder. There is pain with active abduction of the arm at 90 degrees, limiting further abduction. There is a good range of movement elsewhere. Except for weakness attributed to pain, neurovascular examination of the upper limb is normal.

Which of the following is the most likely diagnosis?

Options:
explanation: Glenohumeral instability results in recurrent subluxation or dislocation of the shoulder joint. It is typically found in young, athletic individuals, or individuals with hypermobility disorders. Patients are unable to maintain the humeral head within the glenoid fossa, so they hold their arm close to their body with the unaffected hand to compensate for instability. They do not present with pain on shoulder abduction, unless there was dislocation during the movement.
name: Glenohumeral instability
label: e
answer: no
explanation: Patients with biceps teninditis present with acute, intense pain at the anterior aspect of the shoulder. On examination, you would expect to find tenderness when palpating the biceps tendon which becomes worse with supination of the forearm and elbow flexion, rather than shoulder abduction.
name: Biceps tendinitis
label: c
answer: no
explanation: This is incorrect because cervical radiculopathy usually presents with radicular, nerve-type pain (i.e. shooting or tingling down the arm), and myotomal/dermatomal loss of function. There may be associated neck pain due to osteoarthritis, which may be the cause of the radiculopathy. There may be loss of tendon reflexes. This patient has a normal neurovascular examination and no evidence of myotomal/dermatomal loss of function, nor nerve-type pain.
name: Cervical radiculopathy
label: d
answer: no
explanation: This is correct because this patient describes symptoms of pain in her shoulder with a history of repetitive overhead activities. Pain with active abduction of the shoulder at 60-120 degrees with reduced range of motion is typical for subacromial bursitis. This is due to an inflamed bursa which separates the supraspinatus tendon from the acromial arch and deltoid muscle. This is a clinical diagnosis and first line management is rest with NSAIDs. Steroid injections are sometimes also considered.
name: Subacromial bursitis
label: a
answer: yes
explanation: Adhesive capsulitis is also know as frozen shoulder syndrome as there is inflammation of the glenohumeral joint causing restricted passive and active shoulder movements in all directions. It is usually associated with other conditions such as diabetes mellitus, thyroid disease, rheumatoid arthritis, or recent immobility (for example after surgery or a fracture.) Patients typically have a more chronic course, presenting with shoulder pain followed by freezing (over 6-9 weeks), and then gradual recovery over months. This patient has a relatively acute presentation, and her range of movement is not restricted in all directions. She does not have any of the typical risk factors associated with frozen shoulder syndrome, either.
name: Adhesive capsulitis
label: b
answer: no

Correct answer: a


Learning point: Subacromial bursitis presents with shoulder pain during active abduction, often linked to repetitive overhead activities and relieved by rest and NSAIDs.