Keywords:
Musculoskeletal spine, MR, Imaging sequences, Congenital
Authors:
V. A. Mutafchiyski, B. Milev; Sofia/BG
DOI:
10.26044/essr2019/P-0061
Imaging findings OR Procedure Details
Plain radiogrpah is first imaging method of choice.
It is very helpful and can show vertebral fusion,
anteroposterior narrowing of the vertebral bodies (wasp-waist sign),
hemivertebra,
omovertebral bone,
spina bifida ,
associated scoliosis and Sprengel deformity.
CT is able to better image many of the features seen on plain radiography and in addition may demonstrate canal stenosis.
Central canal narrowing is generally associated with secondary degenerative changes.
It is a valuable tool to assess bony anatomy and is very helpful in pre-operative planning.[8] MRI is indicated in patients with neurologic deficits.
It is excellent in demonstrating canal stenosis and cord compression.
Disc bulge and herniation can be identified that may encroach upon and damage the spinal cord.
MR imaging can also reveal associated conditions such as myelomalacia,
syringohydromyelia,
diastematomyelia,
diplomyelia and Chiari I malformation.
Associated cord abnormalities are seen in 12% of cases .[ Fig.5] [8]
KFS may be associated with failure of vertebral formation,
resulting in hemivertebrae and cleft vertebrae.[4] The chondral stage of vertebral development begins after the membranous stage.
The newly formed primitive membranous vertebrae chondrify at this time.
Paired paramedian foci of chondrification develop to the right and left of the midline within the primitive vertebral body.
[9] In contrast,
during the later ossification stage,
each vertebral body has two ossification centers,
one ventral and the other dorsal.
The lateral hemivertebra results from failure of one chondral cente.
The posterior hemivertebra results from failure during the ossification stage.
The sagittal cleft (“butterfly”) vertebra occurs when separate ossification centers form in each of the chondrification centers but fail to unite.
[Fig.7] A coronal cleft vertebra results from formation and persistence of separate ventral and dorsal ossification centers.
Scoliosis with or without kyphosis occurs in 60%.
[Fig.4] Rib anomalies are present in 10-15% and include fused,
absent or deformed ribs.
[Fig.6] [10]