- See:
-
Myopathic Disorders
-
Ossification of Soft Tissue and Periosteum:
- Discussion:
- most common
collagen vascular diseases which affect muscle;
- pts may be affected at any age;
- may be due to viral infection;
- in adults, note possible concomitant occult neoplasm;
- Clinical Findings:
- systemic illness;
- muscle and joint tenderness;
- progressive weakness which begins in proximal girdle;
-
dermatomyositis:
- look for skin involvement w/ heliotrope rash around eyelids &
erythematous changes, especially over nail beds & knuckles;
- in contrast to
systemic lupus, in which phalanges are involved
& knuckles are spared, dermatomyositis will spare phalanges;
- Labs: CPK &
Sed rate are frequently elevated;
- EMG:
-
EMG of myopathic disorders:
- useful for excluding neurogenic disorders;
- reveals
short-duration, low-amplitude polyphasic units on voluntary activation;
- increased spontaneous activity with
fibrillations &
positive sharp waves;
- polyphasic units of short & long duration may be present w/ chronic disease;
- Radiographs:
- types of dystrophic calcification: (see
ossification of soft tissue)
- superficial masses (small circumscribed nodules) within skin;
- deep discrete subcutaneous nodular masses near joints that can impair movement (calcinosis circumscripta);
- deep linear sheetlike deposits within intramuscular fascial planes (calcinosis universalis);
- Treatment:
-
steroid & immunosuppressive medications are useful;
Review Article: Medical Progress: Polymyositis, Dermatomyositis, And Inclusion-Body Myositis.
Patterns of calcification in childhood dermatomyositis.
CE Blane et al.
AJR. Vol 142. 1984.
p 397-400.
