1. Instability criteria for cervical surgery. The lower cervical spine
Rapanà
UOC Neurochirurgia
Ospedale “L. Bonomo” – Andria (BT)

2. Subaxial cervical spine trauma
….Subaxial spine injuries accounts for the majority of cervical traumatic lesions. About 65% of fractures and more than 75% of all dislocations.
Vaccaro, Spine 2007

3. Cervical spine Biomechanic
Because of the orientation of the cervical spine facet joints, the cervical spine is designed for a great deal of mobility, but it lacks stability

4. Cervical traumas ?

5. Neuroradiological assessment - results
Cervical spine
Neuroradiological assessment - results
Plan X-ray
AP, LL, obliques, dinamiche
Cord
compression
CT scan
Vertebral
instability MR
T1, T2, STIR….

6. Surgical treatment - indications
Cervical trauma
Surgical treatment - indications
Cord
compression

7. Surgical treatment - indications
Cervical trauma
Surgical treatment - indications
….In the cases of traumatic cervical spine fractures and cervical facet dislocation injuries, narrowing of the spinal canal caused by displacement of fracture fragments or subluxation of a vertebra frequently produces spinal cord injury. Reduction of the dislocation deformity helps to restore spinal alignment and the diameter of the bony canal by eliminating bony compression of the spinal cord….

8. Traumi cervicali Cervical trauma Trattamento chirurgico - indicazioni
Surgical treatment - indications
Traumi cervicali
Trattamento chirurgico - indicazioni
Vertebral
instability
“…l’instabilità vertebrale è l’incapacità da parte della colonna stessa a mantenere invariati i rapporti tra i suoi elementi sotto carichi fisiologici sì da impedire la lesione nervosa..”
White & Panjabi, 1978

9. Cervical spine trauma Instability
The amount of normal cervical motion at each level has been extensively described, and this knowledge can be important in assessing spinal stability after treatment.
Flexion-extension motion is about 20 degrees (greatest at the C4-5 and C5-6);
Axial rotation ranges from 2 to 7 degrees at each of the subaxial motion segments;
Lateral flexion is 10 to 11 degrees per level in the upper segments (C2-5) and decreases caudally, with only 2 degrees observed at the cervicothoracic junction.
Radiographic indications of instability. Greater than 3.5 mm of translation (A) or 11 degrees of angulation (B) and widening of the separation between spinous processes are indications of instability on the lateral plain film.
Stress flexion/extension radiographs rarely if ever should be performed if instability is suspected; they should be performed in the awake and alert patient only. In a patient with neck pain, they are best delayed until spasm has subsided, which can mask instability. 

10. Classification criteria
A scheme for the classification of lower cervical spine injuries
C. ARGENSON
Techniques Chirurgicales EMC Orth. Traumat., 1994
Classification criteria
Forces (A,B,C)
Strenght (I,II,III)

11. Conservative treatment
Strenght (I, II, III)
Conservative treatment

12. Anterior approach (or posterior)
strenght (I, II, III)
Anterior approach (or posterior)

13. Somatectomia e plating

14. Strenght (I, II, III)
Combined approach

15. Stabilizzazione 360° C6-C7
Follow-up 11 anni

16. What about the neurological status????
A scheme for the classification of lower cervical spine injuries
C. ARGENSON
Techniques Chirurgicales EMC Orth. Traumat., 1994
Morphological classification
Spinal Instability is deduced
What about the neurological status????

17. Disco ligamentous complex: Ligamentous integrity is directly proprtional to spinal stability. Ligamentuos healing is less predicatble than bony healing
Neurological status: as nerve roots and spinal cord are well protected from trauma, their compromission is an important indicator of severety of spinal column injury

18. Disco ligamentous complex:
Injury morphology:
Compression: a visible loss of height or disruption of an handplate
Distraction: evidence of anatomical dissociation of vertical axis
Translation/rotation: horizontal displacement of one element with respect to the other. In dynamic study translation >3.5 mm or 11° is pathologic
Disco ligamentous complex:
Intervertebral disc, ALL, PLL, yellow ligaments, interspinous and supraspinous ligaments, facet capsules
Discoligamentous injuries is appreciated by indirect means (eg: abnormal bony relationship….)
Neurological status:
Incomplete cord injury requires more urgent treatment
Persistence of cord compression receives one more point
Punteggio 0-3: conservativo
Punteggio 4: conservativo/chirurgico
Punteggio >5: chirurgico

19. 43 years old ♂; car accident; neurological examination: paraplegia with severe diparesis

21. Delayed or missed diagnosis of cervical spine injuries
Patrick Platzer MD*, Nicole Hauswirth MD*, Manuela Jaindl MD, Sheila Chatwani MD, Vilmos Vecsei MD, Christian Gaebler MD
J Trauma 2006 Jul;61(1):150-5
“…The results of this retrospective study show an incidence of delayed diagnosis of 4.9%. Comparing to previous studies, the incidence rate at this trauma unit was relatively low, but the causes for delays in diagnosis appear not to have changed in the last ten to fifteen years…”.
Traumi maggiori e/o pericolo di vita
Errato/incompleto inquadramento clinico
Studio radiografico incompleto
Studio radiografico inadeguato (giunzione cranio-cervicale e cervico-dorsale, dorsale superiore)
Errore interpretativo
Satisfaction of search phenomenon*
* Rischio di “seconda frattura”: 5-15%

22. Grazie per l’attenzione