A calcified intraarticular mass in a man with severe shoulder osteoarthritis : what are the implications?

الملخص EN

Rapidly progressive osteoarthritis in the shoulder in the elderly is often associated with chronic rotator cuff calcifications and damage and with apatite crystals identifiable in the joint fluid.

The key roles of the crystals and rotator cuff lesions although suspected have been disputed.

We describe a 57-year-old man with severe degenerative changes at the right shoulder and other joints.

A calcified mass 2-cm in length was found on radiographs medially in relation to the proximal humeral diaphysis.

At arthroscopy, the mass was confirmed to be in the joint and due to calcified synovia.

Biopsy revealed synovia with apatite like crystal clumps in this mass.

Calcium pyrophosphate crystals were also found but in the cartilage only.

This case with the apatite crystals only in synovia and with destructive arthritis without a complete rotator cuff tear raise the possibility that synovia as a primary site for apatite deposition might be important in the destructive arthritis.

Management of this patient like many with rotator cuff tear arthropathy has been difficult.

Rapidly destructive osteoarthritis at the shoulder, much like that in the patient reported here, has been described under a variety of terms that suggest implications for pathogenesis.

Near et al used the term cuff tear arthropathy to describe glen humeral degenerative arthritis and a rotator cuff tear in twenty-six patients who had required a total shoulder replacement.[1] McCarty et al described 4 elderly women with destructive arthropathy of the shoulder, large effusions, apatite crystals present in the joint effusions and massive tears of the rotator cuffs and coined the term Milwaukee shoulder syndrome.[2], [3], [4] Dieppe et al suggested the terms apatite-associated destructive arthritis and idiopathic destructive arthritis.[5] Calcifications have been noted in the rotator cuff structures but have not been reported in the joint or synovia.[3] We describe a patient with a similar destructive arthropathy, who had a calcified mass about 2-cm in length in the right shoulder, well visible by X-ray and arthroscopy, that was localized to synovia at arthroscopy.

Since this patient did not have prominent rotator cuff disease, our case suggests that intraarticular crystals can be associated with difficult to manage progressive shoulder osteoarthritis without a prominent primary rotator cuff cause.