Diagnostic Approach to Suspected Tendonitis
Diagnosis of tendonitis is primarily clinical, based on history and physical examination findings, with imaging reserved for unclear diagnoses, recalcitrant pain despite adequate conservative management, or preoperative evaluation. 1
Clinical History
Look for the following key historical features:
- Insidious onset of load-related localized pain that coincides with increased activity or a new activity before symptom onset 1
- Progressive pain pattern: In early stages, pain occurs during activity but may subside after warm-up; later stages show increased pain intensity and duration, possibly present at rest 1
- Pain quality: Patients typically describe pain as "sharp" or "stabbing" 1
- Activity correlation: Gradually increasing pain with repetitive loading is the hallmark natural history 2
Important caveat: If multiple tendons are symptomatic simultaneously, evaluate for rheumatic disease rather than isolated tendinopathy 1
Physical Examination
The examination should systematically assess the following:
Inspection
- Assess for muscle atrophy (suggests chronicity), asymmetry, swelling, and erythema 1
- Check for joint effusions, which are uncommon with tendinopathy and suggest intra-articular pathology instead 1
Range of Motion
- Test range of motion, which is often limited on the symptomatic side 1
Palpation
- Palpate for well-localized tenderness that reproduces the patient's activity-related pain 1
Provocative Testing
- Perform physical maneuvers that simulate tendon loading to reproduce pain 1
- Use examination maneuvers that combine passive stretch and active contraction specific to the affected tendon 3
Imaging Studies
Plain radiography is the initial imaging choice for acute injuries and may reveal osteophyte formation at epicondyles, degenerative joint disease, loose bodies, or fractures 1. However, plain radiography has limited ability to demonstrate soft-tissue changes of tendinopathy 1.
Reserve advanced imaging (ultrasonography or MRI) for:
- Unclear diagnoses after clinical evaluation 1
- Recalcitrant pain despite adequate conservative management 1
- Preoperative evaluation 1
Ultrasonography Findings
- Can demonstrate thickening and heterogeneous echogenicity in tendinopathy 1
MRI Findings
- Can show degenerative thickening of tendons, fibrovascular proliferation, and mucoid degeneration 1
Common Pitfalls to Avoid
Terminology matters: Most patients seen in primary care have chronic symptoms suggesting a degenerative condition that should be labeled as "tendinosus" or "tendinopathy," not "tendonitis," as actual inflammation is rarely present histologically 2. This distinction is critical because it affects treatment selection.
Don't over-image: The diagnosis is clinical in the vast majority of cases 3. Imaging should not be routine but rather targeted to specific clinical scenarios where the diagnosis remains uncertain or management decisions depend on imaging findings 1.