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Ganglion Cyst of Radiocapitellar Joint Mimicking Lateral Epicondylitis: Role of Ultrasonography

Lee, Se Won MD; Kim, Su Gym MD; Oh–Park, Mooyeon MD, MS

American Journal of Physical Medicine & Rehabilitation: May 2013 - Volume 92 - Issue 5 - p 459–460
doi: 10.1097/PHM.0b013e31824ad635
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From the Department of Physical Medicine and Rehabilitation, Montefiore Medical Center (SWL, SGK, MO–P), and Department of Neurology, Albert Einstein College of Medicine, Bronx, NY (MO–P).

All correspondence and requests for reprints should be addressed to: Se Won Lee, MD, Montefiore Medical Center/Albert Einstein College of Medicine, 150 East 210th Street, Bronx, NY, 10467.

Financial disclosure statements have been obtained, and no conflicts of interest have been reported by the authors or by any individuals in control of the content of this article.

Lateral elbow pain is most commonly caused by lateral epicondylitis, which is generally diagnosed through clinical evaluation.1 However, persistent pain despite treatment prompts clinicians to consider additional imaging studies for differential diagnoses (e.g., radial tunnel syndrome, radiocapitellar arthritis, osteochondritis dissecans of the capitellum).2 The following case highlights the role of in-office ultrasonographic evaluation in the diagnosis of persistent lateral elbow pain.

A 65-yr-old woman presented to our clinic with a 6-mo history of right elbow pain radiating down to the wrist. Physical examination revealed maximum tenderness on the lateral epicondyle and exacerbation of pain during resisted extension of the wrist. Under a diagnosis of lateral epicondylitis, she was treated with physical therapy and a corticosteroid injection. After 1 mo, she continued to experience significant pain and focal tenderness distal to the radiocapitellar joint (at the level of the radial neck), reproducing radiating pain. Extension of fingers in the right hand was slightly weaker than the uninvolved side; however, subsequent electrodiagnostic findings were normal.

An ultrasonographic evaluation of the right elbow was performed using a portable ultrasound with a 12-MHz linear array transducer. The right common extensor tendon showed normal fibrillar pattern, thickness, and echogenicity. In the area of maximum tenderness, however, a hypoechoic cystic mass was noted between the brachialis and supinator muscles, adjacent to the radial nerve at the level of the radial neck (Fig. 1), which suggested a ganglion cyst originating from the radiocapitellar joint. This finding was subsequently confirmed through magnetic resonance imaging (Fig. 2). The patient deferred aspiration or resection of the ganglion cyst; at a 3-mo follow-up, she reported slight improvement of pain without any neurologic deficit.





Ganglion cysts are an uncommon cause of radial tunnel syndrome,3 the symptoms of which are often described as being more distal and radiating down toward the wrist compared with that in lateral epicondylitis.2 The posterior interosseous nerve may be entrapped with a ganglion cyst when it arises from the anterior capsule of the elbow,4 as was observed in the present case (Fig. 2). Although magnetic resonance imaging can illustrate edema associated with inflammation and reveal a clearer anatomic relationship with nearby neurovascular structures,5 in-office ultrasonography can be utilized as an inexpensive and quick method to diagnose ganglion cysts, as in the present case. For differential diagnoses of uncommon etiologies, early ultrasonographic evaluation may be indicated for patients with lateral elbow pain of atypical presentation.

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1. Orchard J, Kountouris A: The management of tennis elbow. BMJ 2011; 342: d2687
2. Van Hofwegen C, Baker CL III, Baker CL Jr: Epicondylitis in the athlete’s elbow. Clin Sports Med 2010; 29: 577–97
3. Rosenbaum R: Disputed radial tunnel syndrome. Muscle Nerve 1999; 22: 960–7
4. Ogino T, Minami A, Kato H: Diagnosis of radial nerve palsy caused by ganglion with use of different imaging techniques. J Hand Surg 1991; 16: 230–5
5. Jou IM, Wang HN, Wang PH, et al.: Compression of the radial nerve at the elbow by a ganglion: Two case reports. J Med Case Reports 2009; 3: 7258
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