Congenital anomalies/variants

What is a posterior ponticle (aka posticus ponticus)?

Arcuate foramen form when atlanto-occipital ligaments calcifies; transmits the sub-occipital nerve and the vertebral artery

What are radiographic features of Down Syndrome?

20% are born without the transverse ligament; increased ADI indicates atlantoaxial instability; must perform stress films before treatment is commenced

What is Os Odontoideum?

Normally developed cephalic part of the dens is not fused with the C2 body; smooth, wide, lucent defect between the body of C2 body and dens

What is congenital block?

Adjacent vertebra osseously fused from birth; associated with wasp waist and hypoplastic disc

What are physical characteristics of Klippel-Feil syndrome?

Patient presents with a short webbed neck, low hair line, and decreased ROM

What are radiographic characteristics of Klippel-Feil Syndrome?

Multiple congenital blocks, associated with sprengle’s deformity and omovertebral bone

What is Sprengle deformity?

One shoulder blade sits abnormally high on back

What is pedicle agenesis?

Contra lateral pedicle hypertrophy and sclerosis

What is butterfly vertebra?

Failure of the center of the vertebral body to ossify properly

What is hemivertebrae?

Failure of development of a lateral ossification center; isolated wedged vertebra causes a scoliosis; associated with gibbus deformity

What is a gibbus deformity?

A structural spinal condition characterized by a sharp, angular curve in the upper spine, resulting in a pronounced hump-like appearance

What is spina bifida?

Failure of the lamina to fuse; elevated alpha fetoprotein and folic acid deficiency

What is sacralization (transitional vertebra)?

L5 TPs may fuse or form joints with the sacrum

What is lumbarization (transitional vertebra)?

6 lumbars (1st sacral segment appears like a lumbar segment)

What is facet tropism?

Asymmetric articular planes; MC at L5/S1

What is knife clasp syndrome?

Spina bifida of S1 with L5 spinous enlargement; pain on extension

What is coxa vara?

Less than 120 degrees

What is coxa valga?

Greater than 130 degrees

What is normal coxa-femoral angle?

120-130

What line measure coxa-femoral angle?

Mikulicz’s line

What is Madelung’s deformity?

Shortened distal radius, asymmetrical prominence of ulnar styloid, posterior subluxation of distal ulna

What is a negative ulnar variance?

Ulna is unusually shorter than the radius, seen with scapho-lunate dislocation