Management of Cervical Spine Disease in Down's Syndrome:  - PowerPoint Presentation

Slide1

Management of Cervical Spine Disease in Down's Syndrome:  A Neurosurgical perspective 

Dominic ThompsonDepartment of Paediatric NeurosurgeryGreat Ormond StreetLondon

Slide2

Flemish (1515)

Anon

Am J Med Genetics

Slide3

Cervical spinal pathology in Downs syndrome-The controversies

AetiologyDiagnosisScreeningTreatment

Slide4

Aetiology

Slide5

AetiologyPrimary features

Ligamentous laxityHypotoniaHypermobility

Slide6

AetiologyPrimary features

Ligamentous laxityHypotoniaHypermobilitySkeletal consequencesCraniovertebral instability

Scoliosis

Hip instability

Patellar instability

Slide7

Cervical spinal pathology in Downs syndrome

Occipito-atlantal subluxationAtlantoaxial subluxationOs OdontoideumIncomplete C1 ringCervical stenosisSegmentation anomaly

Premature cervical spondylarthrotic myelopathy

Slide8

Cervical spinal pathology in Downs syndrome

Occipito-atlantal subluxationAtlantoaxial subluxationOs OdontoideumIncomplete C1 ringCervical stenosis

Segmentation anomaly

Premature cervical spondylarthrotic myelopathy

Slide9

Os Odontoideum – congenital or acquired?

C1

OS

Slide10

Os odontoideum – developmental anatomy

Sclerotomes cranial and caudal moieties – scleromites Cranial – hypocentrum - disc Caudal – centrum - body

Slide11

Os odontoideum – developmental anatomy

Sclerotomes cranial and caudal moieties – scleromites

Cranial – hypocentrum - disc

Caudal – centrum - body

Slide12

Os odontoideum – developmental anatomy

Sclerotomes cranial and caudal moieties – scleromites

Cranial – hypocentrum - disc

Caudal – centrum - body

C1 hypocentrum

C1 centrum

Slide13

Os odontoideum – developmental anatomy

Sclerotomes cranial and caudal moieties – scleromites

Cranial – hypocentrum - disc

Caudal – centrum - body

C2 hypocentrum -regresses

C2 centrum

Slide14

Os odontoideum – developmental anatomy

Congenital theory of the Os.

= Failure of incorporation of the C1 centrum

Implications

Large os (entire C1 centrum)

Base below joint

Slide15

Os odontoideum – developmental anatomy

Congenital theory of the Os.

= Failure of incorporation of the C1 centrum

Absence of C1 centrum rare

Slide16

Os odontoideum – developmental anatomy

Acquired theory

Trauma to

odontoid

due to instability

Implications

Os relatively small

Base at or above joint line

Slide17

Os odontoideum – developmental anatomy

Slide18

Radiological findings in 12 symptomatic cases (Nader-Sepathi et al 2005

)Atlanto-dental interval 5-13mm (av.7mm)Neural canal width 6-11mm (av.8mm)Atlanto-occipital instability 2 casesOs odontoideum 1

0

cases

Posterior spina bifida 3 cases

Anterior spina bifida 2 casesPars defect C4 1 case

Slide19

Radiological findings in 12 symptomatic cases (Nader-Sepathi et al 2005

)Atlanto-dental interval 5-13mm (av.7mm)Neural canal width 6-11mm (av.8mm)Atlanto-occipital instability 2 casesOs odontoideum 1

0

cases

Posterior spina bifida 3 cases

Anterior spina bifida 2 casesPars defect C4 1 case

Slide20

Atlanto-dental interval 5-13mm (av.7mm)Neural canal width 6-11mm (av.8mm)

Atlanto-occipital instability 2 casesOs odontoideum 10 casesPosterior spina bifida 3 casesAnterior spina bifida 2 casesPars defect C4 1 case

Radiological findings in 12 symptomatic cases (

Nader-Sepathi et al 2005

)

Slide21

Craniovertebral instability

Os OdontoideumDelayed Atlantal ossification

Slide22

Diagnosis

Slide23

Diagnosis of craniovertebral instabilityin Downs Syndrome

Aims To identify children with or at risk of spinal cord damage due to craniovertebral instabilityTo instigate effective treatment

Slide24

What to measure?

Slide25

Defining atlantoaxial subluxation

Atlanto-dental interval (ADI) NR <5mmNeural canal width (NCW) NR >14mm

ADI

Slide26

Defining atlantoaxial subluxation

Atlanto-dental interval (ADI) NR <5mmNeural canal width (NCW) NR >14mm

NCW

Slide27

Defining atlantoaxial subluxation in Downs syndrome

Author

N

ADI

Pueschel 1986

404

4.5mm

Morton 1995

90

4mm

Semine

85

4.5mm

Elliot 1988

67

4mm

Van Dyke 1988

34

5mm

Slide28

Defining atlantoaxial subluxation in Downs syndrome

Author

N

ADI

%

Pueschel 1986

404

4.5mm

14.6

Morton 1995

90

4mm

7.8

Semine

85

4.5mm

12

Elliot 1988

67

4mm

10

Van Dyke 1988

34

5mm

9

Slide29

Defining atlantoaxial subluxation in Downs syndrome

Author

N

ADI

%

Symptoms

Pueschel 1986

404

4.5mm

14.6

1.5

Morton 1995

90

4mm

7.8

0

Semine

85

4.5mm

12

1.2

Elliot 1988

67

4mm

10

0

Van Dyke 1988

34

5mm

9

0

Slide30

Acute vs chronic deteriorationNader-Sepathi et al 20055/12 acute deterioration

Preceeding symptoms in 4Davidson 198831 Downs with neurological symptoms/signs29 symptoms for >1 mnth

Slide31

12 years old

Downs syndromeGait deteriorationClinical signs of myelopathy

Slide32

Extension

Flexion

Slide33

ADI Changes over time

Morton et al 1995

N=67

Measurements 5 years apart

Slide34

Poor clinical and radiological correlation

Ferguson 1987

Slide35

Poor clinical and radiological correlationGait abnormality as a measure of AAS

Specificity 81%Sensitivity 50%

Gait

Radiographs

Normal Abnormal

Total

Normal

Abnormal

92 (91) 9 (9)

21 (70) 9 (30)

101

30

Selby 1991

Slide36

Poor clinical and radiological correlationGait abnormality as a measure of AAS

Specificity 81%Sensitivity 50%Poor reproducibilty in repeat films

Gait

Radiographs

Normal Abnormal

Total

Normal

Abnormal

92 (91) 9 (9)

21 (70) 9 (30)

101

30

Selby 1991

Slide37

Defining Occipito-atlantal subluxation

Coexisting occipito- atlantal instability is common 40-50%Treadwell 1990

Taggart 2000

Difficult to diagnose

Slide38

Defining Occipito-atlantal subluxation

Powers ratio

Slide39

Defining Occipito-atlantal subluxation

Basion-Axial IntervalHarris et al

Slide40

Defining Occipito-atlantal subluxation

Wiesel et al

Slide41

Defining Occipito-atlantal subluxation“Measurement of atlanto-occipital translation by any of these methods is not reproducible”

Lori et al 1996

Slide42

Limitations of Radiographic Measurements in Downs Syndrome

ADI No consensus on measurementPoor reproducibilityPoor correlation with symptomsO-C instability, present but difficult to measure

Slide43

Screening

Slide44

Should Children With Down Syndrome be Screened for Atlantoaxial Instability?

Slide45

Should Children With Down Syndrome be Screened for Atlantoaxial Instability?Special Olympics 1983

All patients with Downs syndrome should have lateral cervical spine X rays ADI>4.5 mm mandates exclusion from high risk sporting activitiesAmerican Academy of Pediatrics 1984Department of Health Standing Medical Advisory Committee 1986

Slide46

Should Children With Down Syndrome be Screened for Atlantoaxial Instability?Special Olympics 1983

All patients with Downs syndrome should have lateral cervical spine X rays ADI>4.5 mm mandates exclusion from high risk sporting activitiesAmerican Academy of Pediatrics 1984Department of Health Standing Medical Advisory Committee 1986

Slide47

Screening Incidence must be common

Screening test should be sensitive and specificAsymptomatic AAS must be a risk factor for symptomatic AASA safe and effective intervention should be available

Slide48

British Guidelines 2009Downs Medical Interest Group of UK

,

Cervical spine X rays are not recommended for the asymptomatic child with Downs syndrome

Medical personnel and carers need to be aware of the potential for neurological symptoms to develop

Slide49

British Guidelines 2009Downs Medical Interest Group of UK

Warning Signs

Neck pain,

Abnormal head posture,

Torticollis, (Wry neck)

Reduced neck movements,

Deterioration of gait and/or frequent falls

Increasing fatigability on walking,

Deterioration of manipulative skills,

Slide50

British Guidelines 2009Downs Medical Interest Group of UK

Action

Full physical and neurological examination

Specialist Referral

Slide51

British Gymnastics AssociationGuidelines for the participation of individuals with Downs syndrome in gymnastics and trampolining

For all applicants to: Registered clubsCompetitive eventsScreening by medical practitionerApproved byBritish Gymnastics Medical Commission

Gymnastics and movement for people with disabilities Technical Committee

Slide52

Clinical screening criteria

A. No signs of myelopathyIncreasing muscle weakness, alteration in muscle toneLoss of sensationDecreasing co-ordinationDiminishing kinaesthetic awarenessChange in walking pattern

New incontinence

B. Neck flexion

Flex to chin on chest without difficulty

C. Neck muscle control

Pulled to sitting position maintaining head neck alignment

Slide53

Results1995-2009

399 applications from Individuals with Down syndrome

6 positive responses

4 Poor head neck muscle control

2 Flex to chin on chest without difficulty

No further follow up

Slide54

Results393 granted membership

No injuries referable to the cervical spine reported during the time period3 in National Squad

Slide55

Treatment

Slide56

Treatment“A safe an effective intervention should be available”

Slide57

Surgery for AAS in Down Syndrome

Author

Number

Re-op (%)

Neurol. Deterioration

Osseous fusion

Doyle

15

6 (40)

4 (27)

12 (80)

Thompson

15

6 (40)

1 (8)

15 (100)

Segal

10

3 (30)

2 (20)

(both died)

4 (40)

Taggard

25

0

0

23 (96)

Slide58

Reasons for failureN=15, 6 failures

Inadequate immobilisationInadequate reduction Inadequate fixationInadequate age

Slide59

Inadequate immobilisation

Reduce and immobilise prior to surgery Maintain immobility post operatively in non instrumented fixation

Slide60

Inadequate fixation

Non union associated

Resorption of rib graft

Limited C1-C2

Nader-Sepathi et al 2005

Doyle et al 1996

Slide61

Inadequate reduction5 yearsAttempted posterior fixation

Inadequate reduction Construct failure

Slide62

Stage I

MUA, halo body jacketStage II

Transoral odontoidectomy

Stage II

Posterior decompression and revision of instrumentation

Slide63

Case 1: Downs syndrome

Stage IMUA, halo body jacketStage II

Transoral odontoidectomy

Stage II

Posterior decompression and revision of instrumentation

Slide64

Case 1: Downs syndrome

Stage IMUA, halo body jacketStage II

Transoral odontoidectomy

Stage II

Posterior decompression and revision of instrumentation

Slide65

Inadequate reduction

Transoral decompression6 out of 15 casesAll had os odontoideum

Slide66

Slide67

Slide68

ConclusionsOsseous anomalies at the CCJ may be consequence rather than cause of instability

Morphometric measures of AAI and OCI lack sufficient sensitivity and specificity to justify screeningEducation rather than screening

Slide69

ConclusionsEarly investigation and treatment of symptomatic patients

Beware the child with Downs!EnsureEffective immobilisationAdequate reductionRigid fixation

Slide70