This patient in his 30’s had chronic unilateral posterior elbow pain of varied severity over the past few years . He could not recall and history of trauma, and had no occupational risks that would predispose him to issues in this region. In the past he had been diagnosed with olecranon bursitis and apparently at that time he said there had been noticeable swelling. The more persistent recent pain was a low level ache that was constantly present. There were no other joint complaints, history of back pain or systemic inflammatory signs.

Ultrasound of the region demonstrated positive doppler signal surrounding the triceps insertion onto the olecranon process.

The patient was subsequently referred for an MRI of the elbow given the marked hypervascularity. The results of which indicated ‘ There is florid marrow oedema within the  olecranon with abnormal signal seen within the distal triceps tendon with abnormal signal also seen within the fat pad between olecranon and triceps tendon. The common flexor and extensor tendons are normal as is the biceps tendon. There is no joint effusion.Severe enthesopathic changes as described.’

The patient presented with insertional enthesitis of the triceps. Enthesitis is inflammation of the entheses, the sites where tendons or ligaments insert onto the bone. It can often be associated with arthropathies like ankylosing spondylitis, psoriatic arthritis, and reactive arthritis (Reiter’s syndrome).

Given the lack of a clear history of mechanical irritation from either occupational hazards or trauma, the patient was referred on to Rheumatology for further input to investigate the possibility of a systemic inflammatory cause for his ongoing chronic complaint.

Some further resources:

Musculoskeletal ultrasound—a state of the art review in rheumatology. Part 2: Clinical indications for musculoskeletal ultrasound in rheumatology, Kane et al (2004), 43:829–838

Diagnostic values of history and clinical examination to predict ultrasound signs of chronic and acute enthesitis, Klauser et al ( 2008), Clinical and Experimental Rheumatology,26: 548-553.

Ultrasound in the evaluation of enthesitis: status and perspectives, Gandjbakhch et al (2011). Arthritis Research & Therapy , 13:R188