Figure 1
T1 weighted sagittal image of lumbar spine
Clinical History
A 44 year old female with a primary diagnosis of Sickle Cell Disease presented with a one month history of lumbar back pain
Imaging Findings
A 44 year old woman with a primary diagnosis of sickle cell disease presented to her GP with a one month history of lower back pain after a sickle crisis. She was already known to the Orthopaedic team, whom she was under 5 years previously, with chronic left hip pain.
The GP suspected possible disc disease and sent the patient for a MRI of her lumbar spine.
Questions:
1) What signs can be seen on MRI in a patient the Sickle Cell Disease
2) What is the cause of her lower back pain?
3) What was the nature of her previous left hip pathology
The GP suspected possible disc disease and sent the patient for a MRI of her lumbar spine.
Questions:
1) What signs can be seen on MRI in a patient the Sickle Cell Disease
2) What is the cause of her lower back pain?
3) What was the nature of her previous left hip pathology
Discussion
1) Sickle Cell anaemia causes destruction of red blood cells stimulating greater production. This occurs within the bone marrow, specifically red marrow, which is present in large quantities in children. As we age, our red bone marrow is converted to yellow or fatty marrow. Sickle Cell causes the persistence and expansion of the body's red marrow. This can be seen with the vertebral bodies on MRI
Fig. 1a is a T1 weighted sagittal image of the lumbar spine and shows some of the musculoskeletal manifestations of sickle cell disease. It shows intermediate to low signal bone marrow, similar to the signal produced by the intervertbral discs. This is a sign of a hypercellular marrow. The marrow should be fatty so return high signal on T1 (Fig 1b)
This hypercellular marrow leads to cortical thinning and bone softening. In this case it results in multiple end plate changes (Schmorl's nodes).
2) The sickling of red blood cells in the bone marrow can lead to infarction and this can happen anywhere in the skeleton. Infarcts often occur in medullary cavities and the epiphyses of children. Infarcts commonly affect the hands and feet of children causing dactylitis and the long bones leading to pathchy intramedullary sclerosis and lucency.
The spine is more often affected in adults and causes vertebral endplate ischaemic changes. Fig. 3 demonstrates abnormal heterogenous signal and oedema of the L5 inferior endplate from a subacute infarction. Specifically the imaging shows asymmetrical endplate change which has a serpiginous quality, characteristic for avascular necrosis. These asymmetrical findings help differentiate AVN from simple Modic endplate change.
The second important differential diagnosis to consider in Sickle Cell patients is discitis or infection of the intervertebral disc, to which these patients are prone. The findings in discitis include high signal in the intervertebral disc on T2WI or STIR, endplate irregularity, oedema or destruction and often a surrounding soft tissue element. Neither of these are present in this case.
Finally the patient's back pain could be due to the small disc bulge shown on the sagittal T2WI. With the onset of pain after the last sickle crisis and the evidence of AVN elsewhere, the patients symptoms were thought most likely to be secondary to the demonstrated infarct than the visualised disc extrusion.
3) Epiphyseal ischaemic necrosis of the femoral heads is common and leads to avasular necrosis by the age of 35 years in 50% of those affected. This patient has undergone a left total hip replacement (Fig. 4) at an early age due to AVN of the left femoral head. This is another complication of an infarct caused by sickle cell disease.
Fig. 1a is a T1 weighted sagittal image of the lumbar spine and shows some of the musculoskeletal manifestations of sickle cell disease. It shows intermediate to low signal bone marrow, similar to the signal produced by the intervertbral discs. This is a sign of a hypercellular marrow. The marrow should be fatty so return high signal on T1 (Fig 1b)
This hypercellular marrow leads to cortical thinning and bone softening. In this case it results in multiple end plate changes (Schmorl's nodes).
2) The sickling of red blood cells in the bone marrow can lead to infarction and this can happen anywhere in the skeleton. Infarcts often occur in medullary cavities and the epiphyses of children. Infarcts commonly affect the hands and feet of children causing dactylitis and the long bones leading to pathchy intramedullary sclerosis and lucency.
The spine is more often affected in adults and causes vertebral endplate ischaemic changes. Fig. 3 demonstrates abnormal heterogenous signal and oedema of the L5 inferior endplate from a subacute infarction. Specifically the imaging shows asymmetrical endplate change which has a serpiginous quality, characteristic for avascular necrosis. These asymmetrical findings help differentiate AVN from simple Modic endplate change.
The second important differential diagnosis to consider in Sickle Cell patients is discitis or infection of the intervertebral disc, to which these patients are prone. The findings in discitis include high signal in the intervertebral disc on T2WI or STIR, endplate irregularity, oedema or destruction and often a surrounding soft tissue element. Neither of these are present in this case.
Finally the patient's back pain could be due to the small disc bulge shown on the sagittal T2WI. With the onset of pain after the last sickle crisis and the evidence of AVN elsewhere, the patients symptoms were thought most likely to be secondary to the demonstrated infarct than the visualised disc extrusion.
3) Epiphyseal ischaemic necrosis of the femoral heads is common and leads to avasular necrosis by the age of 35 years in 50% of those affected. This patient has undergone a left total hip replacement (Fig. 4) at an early age due to AVN of the left femoral head. This is another complication of an infarct caused by sickle cell disease.
Differential Diagnosis List
Vertebral body infarct secondary to a sickle cell crisis
Final Diagnosis
Vertebral body infarct secondary to a sickle cell crisis
References
[1] Ejindu VC, Hine AL, Mashayekhi M, Shorvon PJ, Misra RR (2007) Musculoskeletal Manifestations of Sickle Cell Disease, RadioGraphics 27:1005-1021. (PMID: 17620464)
Case information
| URL: | https://www.eurorad.org/case/6949 |
| DOI: | 10.1594/EURORAD/CASE.6949 |
| ISSN: | 1563-4086 |
Figure 2
T2 weighted sagittal image of lumbar spine
Figure 3
T2 weighted sagittal and axial images of pathology
Series of T2 weighted images showing the region of interest in the L5 vertebral body
Series of T2 weighted images showing the region of interest in the L5 vertebral body
Series of T2 weighted images showing the region of interest in the L5 vertebral body
Series of T2 weighted images showing the region of interest in the L5 vertebral body
T2 weighted sagittal image of lumbar spine
T2 weighted sagittal and axial images of pathology
Series of T2 weighted images showing the region of interest in the L5 vertebral body
Series of T2 weighted images showing the region of interest in the L5 vertebral body
Series of T2 weighted images showing the region of interest in the L5 vertebral body
Series of T2 weighted images showing the region of interest in the L5 vertebral body
