Diabetic myonecrosis is an uncommon complication of diabetes mellitus, occurring in patients with chronic poor glycemic control.
There is a slight predilection for females and patients with type 1 diabetes. The average age of presentation is 40 years.
Patients present with acute onset of pain, tenderness, and swelling, more often in the lower limbs, with the thigh being the most common site.
The exact cause is unknown but diabetic myonecrosis is a skeletal muscle injury thought to be from atherosclerotic occlusion, hypoxia-reperfusion or vasculitis with thrombus.
Diabetic myonecrosis most commonly affects the lower limbs 7:
- diffuse muscle enlargement with decreased attenuation
- hyperattenuating subcutaneous fat 2
MRI findings are non-specific, but a mass-like area of muscle necrosis is noted along with diffuse fascial and subcutaneous soft-tissue oedema 1,2,5,6:
- T1: iso- to hypointense
- T2 Fat-Sat: enlarged muscle(s) with diffuse high signal
- C+ (Gd): heterogeneous/peripheral enhancement
Treatment and prognosis
Normally responds well to conservative treatment and is self-limiting. High (>50%) recurrence rates are reported 2,3. Prognosis is poor with most patients dying within five years 4.
History and etymology
Diabetic myonecrosis was first described by Angervall and Stener in 1965.
On imaging, possible differential considerations include:
- infection, e.g. infectious myositis, necrotising fasciitis, abscess, cellulitis
- acute compartment syndrome
- 1. Chew FS. Skeletal Radiology. Lippincott Williams & Wilkins. (2010) ISBN:1608317064. Read it at Google Books - Find it at Amazon
- 2. Choudhury BK, Saikia UK, Sarma D et-al. Diabetic myonecrosis: An underreported complication of diabetes mellitus. Indian J Endocrinol Metab. 2011;15 (5): S58-61. doi:10.4103/2230-8210.83052 - Free text at pubmed - Pubmed citation
- 3. Sran S, Sran M, Ferguson N et-al. Diabetic myonecrosis: uncommon complications in common diseases. Case Rep Endocrinol. 2014;2014: 175029. doi:10.1155/2014/175029 - Free text at pubmed - Pubmed citation
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- 5. Kattapuram TM, Suri R, Rosol MS et-al. Idiopathic and diabetic skeletal muscle necrosis: evaluation by magnetic resonance imaging. Skeletal Radiol. 2005;34 (4): 203-9. doi:10.1007/s00256-004-0881-8 - Pubmed citation
- 6. May DA, Disler DG, Jones EA et-al. Abnormal signal intensity in skeletal muscle at MR imaging: patterns, pearls, and pitfalls. Radiographics. 2000;20 Spec No (suppl_1): S295-315. doi:10.1148/radiographics.20.suppl_1.g00oc18s295 - Pubmed citation
- 7. Bhasin R, Ghobrial I. Diabetic myonecrosis: a diagnostic challenge in patients with long-standing diabetes. J Community Hosp Intern Med Perspect. 2013;3 (1): . doi:10.3402/jchimp.v3i1.20494 - Free text at pubmed - Pubmed citation