This affection is a form of the so-called muscular rheumatism, and differs essentially from that disease which attacks the joints. The muscles of the loins are the seat of the disturbance, and the animal's movements are stiff and painful; he stands with back arched, and when he walks his limbs are dragged as though partially paralyzed. In certain positions he suffers but little excepting an occasional cramp-like twinge, which is sometimes very severe and elicits a sharp outcry. While the parts affected are sensitive, firm pressure will be borne and seem to afford relief.

There are few or no constitutional symptoms, slight if any fever, and the appetite is rarely impaired. Aside from the tenderness there are no local signs, such as heat, swelling, and redness. In chest-founder or kennel-lameness the affection exists in the muscles of the shoulders and fore legs. The disease may appear either in the acute or chronic form; the duration of the former varies from a few hours to several weeks. The chronic form is obstinate, and persists usually for months. Exposure to cold and damp is an important factor in the causation of this form of rheumatism.

The local treatment consists of soothing applications in the acute form, and blisters or stimulating liniments in the chronic. Measures to improve the general health are important, and iron and other tonics are to be given if the condition of the animal suggests their need.