Rheumatoid Cervical Spondylitis

Question 1

surgical indications for atlantoaxial subluxation

Answer 1

ADI > 10 mm
SAC / PADI < 14 mm
progressive instability
myelopathy
progressive neurologic deficits

Question 2

what causes atlantoaxial subluxation in RA

Answer 2

pannus formation between dens and ring of C1 that leads to the destruction of transverse ligament and dens

Question 3

ADI atlanto dens interval instability defined as?

Answer 3

> 3.5 mm of motion between flexion and extension views

Question 4

ADI motion greater than 7 mm may indicate?

Answer 4

may indicate disruption of alar ligament

Question 5

ADI motion greater than 10mm indicates?

Answer 5

associated with increased risk of neurologic injury and an indication for surgery

Question 6

PADI / SAC stand for?

Answer 6

posterior atlanto-dens interval and space available for cord describe same thing

Question 7

most important predictor of the potential for neurological recovery after the operation is?

Answer 7

the preoperative posterior atlanto-odontoid interval (PADI)
patients who had paralysis due to atlanto-axial subluxation, no recovery occurred if the PADI was less than 10mm
PADI greater than 13mm was predicitive of neurological recovery.

Question 8

what causes basilar invagination?

Answer 8

cranial migration of dens from erosion and bone loss between occiput and C1&C2

Question 9

What are the radiographic lines used to evaluated RA in c-spine?

Answer 9

Ranawat C1-C2 index
McGregor's line
Chamberlain's line
McRae's line
Wackenheim's line

Question 10

what is Ranawat C1-C2 index

Answer 10

center of C2 pedicle to a line connecting the anterior and posterior C1 arches
normal measurement in men is 17 mm, whereas in women it is 15 mm
distance of < 13 mm is consistent with impaction
it is the most reproducible measurement

Question 11

what is Mcgregor’s line

Answer 11

Line drawn from the posterior edge of the hard palate to the caudal posterior occiput curve
cranial settling is present when the tip of dens is more than 4.5 mm above this line
can be difficult when there is dens erosion

Question 12

what is bowtie sigh on lat x-rays

Answer 12

unilateral facet dislocation

Question 13

Basilar Invagination indications for surgery C2 to occiput fusion

Answer 13

progressive cranial migration (> 5 mm)

neurologic compromise

Question 14

what procedure is indicated with brain stem compromise

Answer 14

transoral or anterior retropharyngeal odontoid resection

Question 15

The three main cervical manifestations of cervical rheumatoid spondylitis are?

Answer 15

1) atlantoaxial subluxation,
2) basilar invagination,
3) subaxial subluxation.