Sea Urchin Spine Arthritis of the Hand

PurposeAlthough rare, hand injury caused by puncture with the sea urchin spine can result in serious complications. To emphasize its clinical significance, this article describes a group of patients who sustained chronic granulomatous arthritis induced by puncture with sea urchin spine (designated sea urchin spine arthritis).MethodsFive patients who developed sea urchin spine arthritis of the hand after puncture with sea urchin spine were treated at our hospitals. All lesions involved the proximal interphalangeal (PIP) joint (4 index fingers and 1 middle finger). Patients experienced pain, swelling, and discomfort around the site of puncture immediately after the injury. These initial symptoms subsided within a few days, and secondary symptoms including fusiform swelling, limited motion, and mild pain of the PIP joint appeared from 1 to 2 months later. Laboratory tests of inflammation and blood cell counts were negative. Plain radiographs showed soft tissue swelling and osteolysis but no visible spine. Thorough synovectomy of the PIP joint was performed, and the granulation tissue around the joint was also removed.ResultsNo microorganism was identified from tissue culture or polymerase chain reaction in any of the 5 patients. At a mean follow-up of 21 months, 2 patients exhibited essentially normal active motion of the affected PIP joint, whereas the remaining 3 patients had diminished range of motion.ConclusionsDiagnosis of sea urchin spine arthritis can be made by history of sea urchin spine injury, a symptom-free period before the development of synovitis, and the absence of laboratory test abnormalities. Neither antibiotics nor nonsteroidal anti-inflammatory agents are effective. Undertaken early enough, thorough synovectomy might avoid complications and obtain favorable results.Type of study/level of evidenceTherapeutic IV.