Clinical Images: Flail elbows: destructive calcium pyrophosphate crystal arthritis

The patient, an 89-year-old White man, was hospitalized for an acute vertebral fracture. Clinical examination revealed significant deformities of his wrists, elbows, left knee, and left ankle. He had no history of diabetes, neuropathy, or syringomyelia. He had a history of polyarticular inflammatory arthritis of 40 years’ duration. He was believed to have a systemic arthritis of unclear etiology and was treated over the years with methotrexate, azathioprine, hydroxychloroquine, and eventually infliximab. He required arthrocentesis of knees and elbows on several occasions. Each revealed an inflammatory synovial fluid with intracellular calcium pyrophosphate (CPP) crystals. On current examination he had bilateral flail joints of the elbows with loss of normal joint integrity. There was almost no movement at the wrists but no evidence of active or previous disease at the metacarpophalangeal, proximal interphalangeal, or distal interphalangeal joints. There was a markedly decreased range of motion of the left knee and the left ankle. Radiographs of the elbows revealed a markedly erosive process with joint disarticulation and destruction. Flail joints may be due to trauma, neuroarthropathy (Charcot), and inflammatory arthritis (rheumatoid arthritis, psoriatic arthritis, juvenile idiopathic arthritis, and crystalline arthritis).1 The presentation of CPP crystal arthritis is varied and includes a pseudo-neuroarthropathy, which is well described in patients with disease involving the foot and ankle.2 We present here the first described case of pseudo-neuroarthropathy of bilateral elbows caused by chronic CPP crystal arthritis. Clinicians should be aware of the potential for destructive manifestations of this common crystalline arthritis. Disclosure form. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.