General Spine

Mathew, N, Chakko, MD
Ay-Ming, Wang, MD, Non ASSR Member

Poster

Purpose

This exhibit is intended to demonstrate the magnetic resonance imaging characteristics of rhabdomyolysis involving the paraspinal musculature. The causes and pathophysiology of rhabdomyolysis are briefly discussed. The spectrum of imaging findings are illustrated by presentation of two cases of paraspinal rhabdomyolysis related to alcohol abuse.

Methods & Materials

Two cases of rhabdomyolysis of the paraspinal musculature are presented as demonstrated by MR imaging. Literature review was performed regarding pathophysiology and incidence of rhambdomyolysis.

Results

Rhabdomyolysis represents breakdown of skeletal muscle and may be secondary to trauma, ischemia, physical exertion, metabolic abnormalities, or toxin exposure. Swelling and edema within the fascial compartment may result in compartment syndrome. Blood creatine kinase (CK) levels are relied upon in the diagnosis, with levels greater than five times normal indicating rhabdomyolysis.
Patient one is a 49 year old male with a history of polysubstance abuse . The patient was found wandering the streets and was taken to the hospital by police. Mental status changes were attributed to opiates and benzodiazepines present on drug screen. His initial CK was 4,000 U/L (normal range 40-230), peaking at 16,525 6 hours later. Red urine was noted. After hydration, CK was 2,384 by the time of discharge. The patient complained of chronic lower back pain. On MRI, abnormal T2 hyperintensity and enhancement were apparent in the multifidus and erector spinae muscles, from L3 through the sacrum.
Patient two is a 23 year old male with a history of mental illness, complicated by benzodiazepine and alcohol abuse. The patient developed mental status changes with incoherence and frequent falls. There was a questionable history of seroquel overdose, with a recent episode of excessive alcohol intake also noted. Initial CK was 6,388 U/L, peaking at 88,700 14 hours later. Acute renal failure developed. The patient was treated with hydration and the CK declined to 8,960 by discharge. On MRI, T2 hyperintensity was apparent in the multifidus and erector spinae muscles, from L1 through the sacrum. Foci of T2 hyperintensity and contrast enhancement were noted in the right gluteus medius as well. Precontrast T1 hyperintensity consistent with hemorrhage was noted in the paraspinal muscles, right greater than left.

Conclusion

The presented cases demonstrate the MR findings of rhabdyomyolysis involving the paraspinal musculature, with T2 hyperintensity and contrast enhancement. The second case illustrates superimposed hemorrhage.

References/Financial Disclosures

Khan RJ, Fick DP, Guier CA, Menolascino MJ, Neal MC. Acute paraspinal compartment syndrome. A case report.J Bone Joint Surg Am. 2005 May;87(5):1126-8.

Lu CH, Tsang YM, Yu CW, Wu MZ, Hsu CY, Shih TT. Rhabdomyolysis: magnetic resonance imaging and computed tomography findings. J Comput Assist Tomogr. 2007 May-Jun;31(3):368-74.

Moratalla MB, Braun P, Fornas GM. Importance of MRI in the diagnosis and treatment of rhabdomyolysis. Eur J Radiol. 2008 Feb;65(2):311-5.

Stock KW, Helwig A. MRI of acute exertional rhabdomyolysis–in the paraspinal compartment. J Comput Assist Tomogr. 1996 Sep-Oct;20(5):834-6.

Mathew N. Chakko, M.D., and Ay-Ming Wang, M.D., have no financial interests to disclose.