Not all lateral elbow pain is tennis elbow: Power of point-of-care musculoskeletal ultrasound in diagnosis and care in a pain clinic

Dear Editor,

Chronic lateral elbow pain is commonly attributed to overuse tendinopathy, particularly lateral epicondylitis. While this heuristic is often correct, it can also create diagnostic anchoring, prolonging suffering when the pain generator is uncommon or extra-tendinous. High-resolution musculoskeletal (MSK) ultrasound can rapidly evaluate the common extensor tendon origin with its pathology and surrounding structures like radial neuropathy that may be missed when assessment remains tendon-centric.[1]

We report a case that underscores a patient’s prolonged suffering before diagnosis, the decisive role of MSK ultrasound, and the practical need for accessible pain clinics with point-of-care imaging. A 33-year-old woman reported severe pain over the right lateral elbow for 1 year, which sometimes radiated to the dorsal forearm on activities like cooking and cleaning the floor. In the preceding 9 months, she had consulted multiple orthopaedic surgeons and physicians. The working diagnosis remained “lateral epicondylitis” and “brachioradialis strain,” and she underwent prolonged analgesic treatment/physiotherapy followed by blind platelet-rich plasma (PRP) injection into the common extensor tendon. Despite these measures, she experienced no significant relief, with persistent pain that interfered with sleep, and routine activities.

When she presented to our pain clinic, careful pain phenotyping and focused examination shifted the diagnostic axis. The maximal tenderness was over the brachioradialis region rather than the lateral epicondyle. Pain was accompanied by mild tingling along the dorsal forearm, and her numeric rating scale (NRS) score was 7/10. Given the atypical site, failed PRP treatment, and sensory symptoms, point-of-care MSK ultrasound was performed at the point of maximal tenderness that revealed a lobulated, septate cystic lesion (~6.6 × 4.4 mm) situated in the intermuscular plane between brachialis and brachioradialis muscles, exerting compressive effect on the radial nerve [Figure 1]. Dynamic scanning and graded probe pressure reproduced her pain, strengthening the anatomical–clinical correlation. Magnetic resonance imaging (MRI) of the right forearm subsequently demonstrated similar findings, supporting the ultrasound diagnosis and aiding surgical planning.

Figure 1.

Ultrasound images of both short and long axis scans of anterior elbow, where blue bold arrow points to lobulated cyst arising between brachialis (BR) and brachioradialis muscle (BRD). R-Radial head, H-Humerus, CEPH- Cephalad, CAUD-Caudad, MED-Medial, LAT-Lateral

The patient underwent surgical excision of the cyst with decompression of the nerve. At 3 months follow-up, she had complete symptom resolution and she returned to normal function. The contrast between a year of disability and a rapid recovery after targeted treatment highlights how small space-occupying lesions can cause outsized suffering when the diagnostic lens is fixated on a particular structure.

Lateral elbow pain was once equated almost exclusively with tennis elbow, but advances in imaging and arthroscopy have revealed a broad differential. Beyond tendinopathies, causes now recognised include intra-articular mechanical lesions, elbow instability, radial tunnel syndrome, osteochondral defects, degenerative arthritis, and rare compressive cystic lesions.[2] A case series by Lifchez SD et al.[3] demonstrates meaningful neurological recovery after excision/decompression of cystic lesion when the diagnosis is made in time. Refractory lateral epicondylitis should be a diagnosis of reconsideration, not escalation. MSK ultrasound is uniquely positioned to address these gaps because it is rapid, inexpensive, dynamic, and able to interrogate superficial soft tissues and peripheral nerves at the exact site of maximal tenderness. In contrast to MRI, bedside ultrasound allows immediate correlation of symptoms with the visualised pathology and can detect small lesions that are clinically relevant but easily overlooked. In this context, a report by Erol et al.[4] illustrates how targeted imaging and guided intervention can achieve both diagnostic clarity and therapeutic benefits in atypical lateral elbow pain caused by ganglion cyst.

Finally, this patient’s journey illustrates the broader systems issue. Pain clinics are often perceived as end-stage analgesia services; however, multi-disciplinary pain clinics can function as diagnostic accelerators by combining detailed pain assessment, point-of-care MSK ultrasound, and coordinated referral pathways. Evidence from systematic reviews supports the value of multi-disciplinary approaches for chronic pain outcomes compared with usual or single-modality care.[5]

We advocate a low threshold for MSK ultrasound evaluation in persistent, atypical lateral elbow/proximal forearm pain, and we emphasise strengthening pain clinic services where imaging and multi-disciplinary decision-making can be delivered early.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient consented to the images and other clinical information to be reported in the journal. The patient understands that her name and initials will not be published and due efforts will be made to conceal her identity, but anonymity cannot be guaranteed.

Study data availability

De-identified data may be requested with reasonable justification from the authors (email to the corresponding author) and shall be shared after approval as per the authors’ institution’s policy.

Disclosure of use of artificial intelligence (AI)-assistive or generative tools

The AI tools or language models (LLM) have not been utilised in the manuscript, except that software has been used for grammar corrections.

Author contributions

RKS was involved in concepts/design, editing, review and approval. AK was involved in literature search, data acquisition, data analyses, manuscript preparation, editing. SR and SK were involved in concepts/design, conduct of case, data acquisition, data analyses.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.