This document summarizes CT findings related to congenital anomalies, infections, and degenerative conditions of the spine. It describes common congenital anomalies such as spina bifida occulta, coronal cleft vertebra, and block vertebra. It also discusses spinal infections including bacterial spondylodiskitis caused by pathogens like Staphylococcus aureus and tuberculous spondylitis. Finally, it reviews degenerative changes in the spine seen with aging and conditions like ankylosing spondylitis. CT is useful for evaluating bony abnormalities, spinal infections, and the extent of fusion in diseases like ankylosing spondylitis.

1. CT STUDY OF CONGENITAL
ANOMALIES, INFECTIONS AND
DEGENERATIVE CONDITIONS OF SPINE
PRESENTED BY : DR. B.BORTHAKUR
PROFESSOR AND HEAD, DEPT OF ORTHOPAEDICS, SMCH

2. CONGENITAL ANOMALIES OF THE VERTEBRAL
COLUMN
• Spina bifida occulta
• Coronal cleft vertebra
• Butterfly vertebra
• Hemi vertebra
• Block vertebra
• Sacralisation of 5th lumbar vertebra
• Lumbarisation of 1st sacral vertebra

3. Spina bifida occulta
Cause: incomplete fusion of
halves of the vertebral arches
resulting in midline defect
usually in lumbosacral region
Feature: It varies, but generally
the small bones (vertebrae)
that make up the spine don’t
form fully and may have gaps
between them.

4. Computed tomography (CT) scan in the axial plane of the
cervical spine showing the defect of fusion of spinous
process of T1

5. Coronal cleft vertebra in an infant
Coronal cleft vertebra:
Cause: persistence of
dorsal and ventral
ossification centres
separately
• Most common in lumbar
spine

6. Butterfly vertebra
distance.
Butterfly vertebra

7. BUTTERFLY VERTEBRA

8. Hemivertebra
Cause: failure of one of the
chondrification center to appear and
subsequent failure of half of vertebra
to form
Types: based on location lateral,
dorsal and ventral
Feature: defective vertebra produce
scoliosis
Most likely to cause neurologic
problems
HEMIVERTEBRA

9. HEMIVERTEBRAE
HEMIVERTEBRA

10. Block vertebra
• Cause: embryological failure of normal spinal segmentation
• Radiologic features: characteristic triad of hypoplastic vertebral
body(wasp-waist deformity, C concavity), small/ abscent disc, variable
posterior arch fusion

11. n.
Acquired vertebral body fusion
of C5 and C6.
Block vertebra with congenital fusion of C3 & C4 .
Note the presence of a “waist” at the site of
fusion.
BLOCK VERTEBRA

14. Spinal Infection
Bacterial spondylitis/spondylodiskitis
• Pyogenic spondylitis is usually caused by hematogenous spread of
infection.
• Sources of septic embolism are most commonly from the
genitourinary tract, followed by skin and respiratory infections.
• Bacterial spondylitis may also be caused by direct extension from
penetrating trauma, surgical intervention, or from adjacent infected
structures.

15. • Patient presentation is variable in patients with pyogenic
infections, but typically involve focal back pain, myalgia, and
muscle spasm.
• The causative organisms are predominantly gram-positive, with
Staphylococcus aureus as the most common bacterium.
• Enterobacteriaceae comprise approximately 30% of cases, with
other less common causative organisms including Staphylococcus
epidermidis, Haemophilus influenzae, and Streptococcal species.
• Escherichia coli is the most common gram-negative source .
• Pseudomonas is commonly seen in intravenous drug abusers.
• Salmonella is relatively more commonly encountered in patients
with Sickle cell disease

16. • Radiographic evidence of osseous demineralization
requires 30% to 40% loss of the osseous matrix, which may
occur two weeks after onset of clinical symptomology.
• CT is not considered to be of much utility for diagnosis of
intervertebral disk infection.
• However, CT is often utilized in image guidance to obtain
samples of infected specimens, for both osseous and non-
osseous tissue.
• The mainstay to diagnose and assess the extent of disease
involvement is with MR imaging. MR is the most sensitive
imaging modality to assess for early osteomyelitis .
• The earliest imaging finding (across all imaging modalities) is
osseous bone marrow edema.

17. Axial CT demonstrates destructive changes involving
the T2 vertebral body

18. Pyogenic Spondylodiskitis with posterior mediastinal abscess.
Sagittal CT demonstrates osseous destruction of the endplates at the T2
,T3 level with reactive sclerosis of the adjacent vertebral bodies

19. Tuberculous spondylitis/spondylodiskitis
• The thoracolumbar junction is the most commonly affected segment of the
spine involved in tuberculous infection.
• Cervical and sacral spine involvement is less common .
• Spinal tuberculosis usually begins in the anterior aspect of the vertebral
body, either at its superior or inferior margin.
• The infection typically spreads in a sub-ligamentous fashion, usually deep
to the anterior longitudinal ligament and may traverse multiple vertebral
levels.
• The route of disease spread generally occurs anterolaterally. In
contradistinction to pyogenic diskitis, tuberculous disease spares the
intervertebral disk, as Mycobacterium tuberculosis lacks the proteolytic
enzymes to break down the disk

20. Axial CT scan shows the fragmentary bone pattern and large paraspinal soft tissue
abscesses with initial calcification of the wall
TUBERCULOUS SPONDYLITIS

21. Tuberculous spondylitis and pyogenic spondylitis
Tuberculous spondylitis and pyogenic spondylitis :
• para- or intraspinal abscess : presence favors tuberculous spondylitis
• abscess wall:
• pyogenic spondylitis walls are thick and irregular
• tuberculous spondylitis walls are thin and smooth
• postcontrast paraspinal abnormal signal margin
• pyogenic spondylitis margins are ill-defined
• tuberculous spondylitis margins are well-defined
• abscess with postcontrast rim enhancement
• involves the disc in pyogenic spondylitis
• involves vertebral intraosseous in tuberculous spondylitis
• number of vertebral bodies involvements
• pyogenic spondylitis tends to only involve no more than 2 vertebral bodies
• tuberculous spondylitis involves multiple vertebral bodies
• location
• lumbar spine are common locations for pyogenic spondylitis
• thoracic spine are common locations for tuberculous spondylitis
• intervertebral disc
• moderate to complete destruction in pyogenic spondylitis
• mild destruction or spared in tuberculous spondylitis
• vertebral bone
• seen and notably severe in tuberculous spondylitis

22. Fungal infection
• Fungal infection of the spine is most commonly encountered
in immunocompromised patients.
• These include patients with the human immunodeficiency
virus (HIV), diabetes mellitus, patients on certain
chemotherapeutic agents, or post transplant patients on
immunosuppressive therapy.
• Candida and Aspergillus are MC causes
• Similarly to bacterial and mycobacterial infection, fungal
infections may lead to diskitis/osteomyelitis.
• The imaging findings are similar to that of pyogenic
infection.

23. Degenerative Spine Disease
• The prevalence of degenerative spine disease is
linearly related to age.
• The loss of height of the intervertebral space is the
earliest sign of disc degeneration on plain radiographs.
• Other signs, including sclerosis of the vertebral
endplates, osteophytes, subchondral cyst, vacuum
phenomenon and calcification, are more reliable,
though they indicate late degenerative changes.

25. Vacuum phenomenon

26. Ankylosing spondylitis
• A seronegative spondyloarthropathy, which results
in fusion (ankylosis) of the spine and sacroiliac (SI)
joints, although involvement is also seen in large
and small joints.
• SI joints- Sacroiliitis is usually the first
manifestation and is symmetrical and bilateral
• the SI joint first widen before they narrow
• subchondral erosions, sclerosis, and
proliferation on the iliac side of the SI joints
• at end-stage, the SI joint may be seen as a thin
line or not visible

27. Spine
• Early spondylitis is characterized by small erosions at the corners
of vertebral bodies with reactive sclerosis: Romanus lesions of
the spine (shiny corner sign)
• Vertebral body squaring
• Diffuse syndesmophytic ankylosis can give a "bamboo spine"
appearance.
• Syndesmophytes are classically described as paravertebral
ossification running parallel to the spine.
• Linear ossification along the central spine; representing
interspinous ligament ossification can give a "dagger spine"
appearance on frontal radiographs
• Ossification of spinal ligaments, joints and discs.
• Apophyseal and costovertebral arthritis and ankylosis
• Enthesophyte formation from enthesopathy.

28. CT scan (sagittal reformation) shows
sclerotic changes and erosions of
vertebral endplates
Coronal CT scan of sacroiliac joints shows
multiple subchondral erosions (arrows) and
sclerosis (arrowheads).
SHINY CORNER SIGN

29. Sagittal and coronal CT scans of thoracic and lumbar spine show syndesmophytes
corresponding to osseous bridge between two adjacent vertebrae
BAMBOO SPINE

30. Axial CT scan and volume reformation of sacroiliac joints show complete ankylosis
with homogeneous osseous bridge passing through
articulations
FUSION OF SI JOINTS

31. THANK YOU