Air in the Spine – Look for Emphysematous Osteomyelitis

A 60-year-old gentleman presented with weakness of both lower limbs. He had uncontrolled diabetes mellitus with a diabetic foot ulcer. As magnetic resonance imaging (MRI) did not show any compressive pathology, muscle biopsy of right vastus lateralis was done which was suggestive of myocytolysis and was managed with steroids. He had improvement in paraparesis to 4/5 following treatment. Three weeks later, he presented to us with continuous fever, low back pain, and worsening paraparesis. MRI thoracolumbar spine was repeated which showed L2 vertebral collapse with a paraspinal collection [Figure 1a]. Computed tomography scan done showed collapse of the L2 vertebral body with air pockets in the spinal column, anterior, and central rather than paradiscal. Bubble-like air pockets were seen extending into a bulky right psoas muscle [Figure 1b,c,d]. He underwent posterior stabilization followed by anterolateral approach and debridement of the infected disc and muscle. Microbiological evaluation indicated that the causative organism was Morganella morganii. Strict control of diabetes and antibiotics were continued following which he had gradual improvement in paraparesis. On follow-up he has improved in his neurology sufficient to walk independently.Figure 1: (a) MRI T2W sagittal view showing destruction of the L2 vertebral body. (b) Sagittal view of CT scan of the thoracolumbar spine showing destruction and collapse of the L2 vertebral body with a pocket of air at the anterosuperior angle. In the axial CT section (c) these air pockets are seen extending into the anterior paravertebral space. In the coronal CT section (d) there is air seen bilaterally in the psoas muscles with the typical “bubble” type extension especially on the right side where the muscle is also bulkyNondegenerative causes of air in the spinal column include trauma, post-surgical change, lymphangiomatosis of the bone, osteonecrosis, tumors, and infection.[1] Emphysematous osteomyelitis of the spine is a rare but potentially fatal condition that must be considered on the identification of intraosseous gas on imaging. The diagnosis of infection in the presence of vertebral gas can be assumed by a characteristic bubble-like pattern and a paraspinal extension of the gas into the muscles.[2] The reported mortality is approximately 32 per cent.[3] Luey et al. in 2012 found only ten cases of spinal EO in literature.[2] It is commonly seen in the setting of an associated comorbidity like diabetes, malignancy, and other causes of immunosupression.[3,4] The common organisms isolated belong to Enterobacteriaceae or anaerobes, though rarely it can be caused by M. tuberculosis, Staphylococcus.[1,2,3,4] Early recognition and immediate treatment with debridement and fusion are critical for preventing the potentially devastating consequences of the disease. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.