Joint effusions, chondrocalcinosis and other rheumatic manifestations in hypothyroidism. A clinicopathologic study.

Twelve patients with severe hypothyroidism and rheumatic signs and symptoms were studied before or within four days of receiving thyroid replacement therapy. Eight patients had synovial effusions. Seven effusions were extremely viscous and six contained calcium pyrophosphate crystals. Leukocyte counts were less than 1,000/mm3, except in two patients during crystal-induced synovitis. "Bulge signs" were present but often sluggish, possibly because of the viscosity of the fluid. Flexor tendon sheath thickening, joint laxity and popliteal cysts were documented. All patients complained of generalized stiffness and two had proximal myopathy. Roentgenograms were obtained in 11 patients, and chondrocalcinosis was identified in seven. Needle synovial biopsy specimens in five patients showed only mild inflammation in the thick synovium. These findings can suggest hypothyroidism, a treatable disease, as the cause of musculoskeletal problems.