48-year-old male:
– Heavy smoker
– Depressive syndrome
Found lying unconscious at home, in lateral position (opioid overdose)
Erythema and limited movement of the left shoulder
Blood test: CK 7949 u/l. Negative blood and aspiration cultures (no infection)
What do you see?
Findings
CT: Low attenuation area involving the posterior aspect of the deltoid muscle and the lateral aspect of the pectoralis major muscle. Superficial and deep fascia edema. No enhancing walls neither gas is seen.
MRI: Postcontrast T1FS images show hypointense unenhancing central muscle fibers surrounded by thick rim enhancement involving the posterior deltoid, teres minor, and pectoralis major muscles . Thickened and hyperenhancing adjacent fascia and reactive muscle edema are also noted.
What is the most likely diagnosis?
Rhabdomyolysis (type 2: myonecrosis)
– Injury to skeletal muscle that involves leakage of large quantities of potentially toxic substances into plasma.
– Type 1: homogeneous signal changes and contrast enhancement. Ischemic or reversible ischemic reaction.
– Type 2: homogeneous or heterogeneous signal changes and rim enhancement. Irreversible muscular necrosis (myonecrosis).
– Deep tissue injury: severe pressure ulcer, characterized by necrotic tissue mass under intact skin.
– CK > 1000 – 5000 iu/l “cut-off”.
– Risk factors: postoperative patients (position), obesity, male gender, diabetes, surgical bleeding…