1. Spinal Laxity, Hypermobility and Instability A Surgeon’s View
Christian Ulbricht
Consultant Spinal Neurosurgeon
Imperial College Healthcare NHS Trust

2. Understanding the patient Understanding the pathophysiology / mechanical problems Surgical options

3. Key Issues Complex needs / multiple complaints
What is causing the pain?
Surgeons only have options for segmental problems

4. Case ? Anterior spinal cord herniation

5. Clinical Hypermobility in the spine

6. Undetected Neural Compromise / Instability
Flexion / extension MRI
Francis W. Smith MD. FRCR, FRCS, FRCP, FFSEM(UK). Clinical Director, Medserena U.K. Clinical Professor of Radiology, University of Aberdeen. Professor of Health & Sport Science, The Robert Gordon University.

7. Fluctuating spinal stenosis Erect
Supine
Fluctuating spinal stenosis
Erect
Sit Flexion
Sit Neutral
Sit Extension
Curtesy of Prof Francis W. Smith MD

8. Sit Flexion Sit Neutral Sit Extension
Curtesy of Prof Francis W. Smith MD

9. CERVICAL SPINE ANGLE
Curtesy of Prof Francis W. Smith MD

10. CERVICAL SPINE ANGLE Normal/Control E.D.S. Neutral 17.1o 17.7o
Flexion o o
Extension o o
Curtesy of Prof Francis W. Smith MD

11. Upright / dynamic MRI UPpright Recumbent
Curtesy of Prof Francis W. Smith MD

12. Curtesy of Prof Francis W. Smith MD
S N

13. Specific views to assess the atlanto-axial joint
Normal alignment
20o of dislocation at the atlanto-axial joint
Curtesy of Prof Francis W. Smith MD

14. Clivo-vertebral or Clivo-axial angle
(normal range 150°-180°).
Curtesy of Prof Francis W. Smith MD

15. (The basion axial interval is the length of a line drawn between the tip of the basion and a line drawn along the posterior aspect of the odontoid peg. The basion dental interval is a distance measured between the tip of the basion and the tip of the dens. Both these measurements should be less than 12 mm. If they are greater than 12 mm, then occipito-atlantal disassociation has occurred. These measurements are often referred to as "The rule of 12")
(The Grabb-Oakes measurement is the perpendicular distance from the BpC2 line [Basion to posterior inferior C2 body] to the dura.
A value greater than or equal to 9 mm indicates ventral brainstem compression)

16. Cranio-cervical junction
Cervico-Medullary-Syndrome
Headache, sub-occipital or neck pain
Diplopia , decreased or blurred vision
Dizziness, vertigo, imbalance
Tinnitus or decreased hearing
Dysautonomia, POTS, syncope or pre-syncope
Dysarthria, dysphagia, choking
Altered breathing and sleep architecture
Weakness, clumsiness, spasticity,
Paraesthesia, dysesthesia
Gait changes,
Urinary urgency or frequency

17. Pathophysiology of cord / medulla compression
Neural stretch injury causes apoptosis and cell death

18. Surgical Targets for Hypermobility
Compromise of neural structures
Segmental instability causing pain
? Prophylactic surgery
Trial brace before surgery
Main decision : risks vs benefits

19. Decompression Fixation ? Dynamic stabilisation
Surgical Options
Decompression Fixation ? Dynamic stabilisation

20. Dynamic stabilisation
Surgical Options
Dynamic stabilisation
Flexible rod system (Dynesis), Percudyn

23. Surgical Options Fixation
Simple single level vs complex multilevel / cranio-cervical
No options for thoracic spine
Lumbar fixation

26. Surgical Options Decompression
Limited indication for decompression only in EDS patients
Usually combined with fixation
Roots vs cord/ cauda equina

27. Risks vs Benefit
Risks
Immediate: infection, nerve / spinal cord damage, vascular injury, implant malpositioning
Delayed: no improvement, loosening of implants, adjacent segment disease

32. Conclusions Complex patients
Key is understanding of patient needs and identifying segmental pathology
Difficult balance of risks / benefits
Surgery only for clear indications