- Discussion: (tumoriform focal muscular degeneration);
- poorly defined process which occurs in long term diabetics;
- other names for this syndrome include: tumoriform focal muscular degeneration and idiopathic diabetic muscle infarction;
- may be confused w/ sarcoma, deep infection, or even a compartment syndrome (the mass may be very tender);
- most often affects the quadriceps, and less often the thigh adductors and gastroc-soleus muscles are involved;
- labs: elevated creatinine kinase will be increased in 50% of these patients;
- MRI findings:
- absence of discrete mass and MRI signal pattern consistent w/ intra-muscular edema and
inflammation involving one or more major muscle groups;
- look for significant increased signal on T2 (and to a lesser extent T1);
- in diabetic muscle necrosis, look for involvement of non-continguous muscle compartments which help distinguish DMI from polymyositis;
- closed needle biopsy may be needed in some cases in order to clinch the diagnosis;
- note that the histologic appearance of DMI may appear similar to polymyositis;
- pitfalls:
- attempts to excise the necrotic muscle or to begin aggressive PT are associated w/ a
high rate of complications, recurrent disease, and/or recurrence of symptoms;
- treated conservatively, symptoms usually subside within 6 months;
- references:
- Idiopathic necrosis of skeletal muscle in patients who have diabetes. Report of four cases and review o the literature.
TA Damron MD et al. JBJS. Vol 80-A. No 2. Feb 1988. p 262.
- Diabetic muscle infarction: radiologic evaluation.
DP Chason et al.
Skeletal Radiology. Vol 25. 1996. p 127-132.
- MRI evaluation of diabetic muscle infarction.
MA Van Slyke and BE Ostrov.
Magnet. Reson. Imag. Vol 13. 1995. p 325-329.
- Clinical and radiographic aspects of idiopathic diabetic muscle infarction.
AJ Aboulafia et al.
JBJS. Vol 81-B. 1999. p 323-326.
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