Adhesive Capsulitis
This patient's presentation is most consistent with adhesive capsulitis (frozen shoulder). The combination of equal restriction in both active and passive internal and external rotation, normal strength on resisted testing, nocturnal pain, and risk factors including breast cancer treatment and hypothyroidism strongly support this diagnosis over the other options 1, 2.
Clinical Reasoning
Key Diagnostic Features Present
Equal restriction of active and passive range of motion is the hallmark finding that distinguishes adhesive capsulitis from rotator cuff pathology, where passive motion would be preserved 1, 2
External rotation is typically the most severely affected motion in adhesive capsulitis, followed by abduction, then internal rotation—creating the classic "capsular pattern" 1, 2
Normal strength with resisted testing excludes rotator cuff tears, which would demonstrate focal weakness during specific resistance maneuvers 1, 2
No pain with resisted isometric abduction, external rotation, or forearm supination effectively rules out rotator cuff tendinopathy and biceps tendinitis, as these conditions produce pain with specific resistance testing 2
Risk Factor Profile
Breast cancer treatment history is a recognized risk factor for adhesive capsulitis, as cancer-related treatments have been linked to higher incidence of this condition 3, 2
Hypothyroidism is a well-established systemic risk factor for developing adhesive capsulitis 2, 4
Middle-aged female demographic fits the typical patient profile for primary adhesive capsulitis 5
Why Other Diagnoses Are Excluded
Biceps Tendinitis (Option 2)
- Would produce pain with resisted supination of the forearm, which this patient does not have 2
- Typically does not cause global restriction of passive range of motion 2
- The anterior shoulder tenderness is too vague and medial to the deltoid to localize to the biceps tendon 2
Cervical Radiculopathy (Option 3)
- Would present with neurologic findings such as dermatomal sensory changes, reflex abnormalities, or weakness in specific nerve root distributions—none of which are present 2
- Normal strength and sensation in the elbow, wrist, and hand argue strongly against nerve root compression 2
- Pain pattern does not follow a dermatomal distribution 2
Glenohumeral Osteoarthritis (Option 4)
- Would typically show crepitus on examination and radiographic changes 6, 7
- Usually presents with more gradual onset over years rather than six months 7
- While it can restrict motion, the pattern and severity in a 57-year-old without significant trauma history is less typical 6
Clinical Pitfalls to Avoid
Do not confuse adhesive capsulitis with rotator cuff pathology—the key differentiator is that rotator cuff tears show focal weakness with specific resistance testing and preserved passive motion, whereas adhesive capsulitis demonstrates equal restriction in both active and passive motion 1, 2
Avoid delaying diagnosis beyond 6-8 weeks, as early intervention with corticosteroid injection and physical therapy may shorten the overall duration of symptoms and prevent permanent functional limitations 2, 8
Do not recommend aggressive overhead pulley exercises, as these can worsen shoulder complications, particularly in patients with risk factors like prior cancer treatment 3, 1
Recommended Next Steps
Initiate treatment with intra-articular corticosteroid injection targeting the glenohumeral joint (since capsular involvement is predominant) combined with physical therapy emphasizing gentle stretching in external rotation and abduction 1, 8
Consider MRI without contrast if the diagnosis remains uncertain or if symptoms do not improve with initial conservative management, as coracohumeral ligament thickening on MRI yields high specificity for adhesive capsulitis 2, 4
Prescribe acetaminophen or NSAIDs for routine pain control, provided no contraindications exist 1, 7
Refer for physical therapy focusing on gentle range-of-motion exercises, avoiding aggressive passive stretching that could exacerbate symptoms 1, 8