myositis ossificans

myositis /myo·si·tis/ (mi″o-si´tis) inflammation of a voluntary muscle.

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myositis fibro´sa  a type in which connective tissue forms within the muscle.

inclusion body myositis  a progressive inflammatory myopathy primarily involving muscles of the pelvic region and legs.

multiple myositis  polymyositis.

myositis ossi´ficans  myositis marked by bony deposits or by ossification of muscle.

proliferative myositis  a benign, rapidly growing, reactive, nodular lesion similar to nodular fasciitis, but characterized by fibroblast proliferation within skeletal muscle.

trichinous myositis  that due to the presence of Trichinella spiralis.

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myositis os·sif·i·cans (-sf-knz)

n.

Ossification or the deposit of bone in muscle tissue, causing pain and swelling.

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myositis ossificans

[əsif′əkanz]

a rare inherited disease in which muscle tissue is replaced by bone. It begins in childhood, with stiffness in the neck and back, and progresses to rigidity of the spine, trunk, and limbs. The administration of diphosphonates may prevent the abnormal deposition of bone, but there is no cure after it has occurred. Metabolism of calcium and phosphate remains normal throughout the course of the disease. Compare myositis.

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myositis [mi″o-si´tis]

inflammation of a voluntary muscle; called also initis.

myositis fibro´sa a type in which there is a formation of connective tissue in the muscle.

multiple myositis polymyositis.

myositis ossi´ficans myositis marked by bony deposits in muscle.

trichinous myositis that which is caused by the presence of Trichinella spiralis.

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myositis

inflammation of a voluntary muscle. Causes heat, swelling, pain and lameness if a limb is affected. Trauma is the common cause, especially in racing and work horses. Blackleg is a specific myositis. See also polymyositis.

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atrophic myositis

a form of masticatory myositis in dogs. There is a chronic, progressive atrophy and fibrosis of the masticatory muscles of dogs which finally makes it impossible for the mouth to be opened wider than a few inches.

eosinophilic myositis

1. a form of masticatory myositis seen in German shepherd dogs. It is acute, often recurrent, and there is painful, bilaterally symmetrical swelling of the masticatory muscles, mainly temporals and masseters. Often there is an eosinophilia found in the hemogram. Occasionally other muscles are also involved. There is a progressive atrophy and fibrosis of the muscles, frequently resulting in an inability to open the mouth. In the latter it may be confused clinically with atrophic myositis (above).

2. a lesion found at meat inspection. It reduces the value of the carcass. The cause is unknown.

familial myositis

see canine familial dermatomyositis.

myositis fibrosa

a type in which there is formation of connective tissue in the muscle.

masticatory myositis

see atrophic myositis and eosinophilic myositis (above).

maxillary myositis

a slowly developing myogenic degeneration of the muscles of the jaw in horses.

multiple myositis

polymyositis.

myositis ossificans

a generalized myositis with dystrophic ossification in muscle. It occurs in pigs, in which it may be familial, and rarely in dogs and cats.

trichinous myositis

caused by the presence of Trichinella spiralis.

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myositis ossificans

Bone formed within muscle; localized MO is 2º to trauma resulting from a blow or muscle tearing; generalized MO is AD, often accompanied by aplasia of the thumb, great toe, or rarely other digits, in which the first 'tumor' occurs in the paravertebral or cervical region, followed by multiple ossifying tumors, forming calcifying bridges across muscles and joints resulting in massive rigidity and the Pt is turned into 'stone'. See Zoning phenomenon.