Spine

Key muscles

Key sensory points

Reflexes

Shoulder elevation (M. deltoideus)

Shoulder

C5/6 Biceps tendon reflex

Elbow flexion (M. biceps, M. brachioradialis)

Lateral upper arm

C5/6 Brachioradial tendon reflex

Wrist extension (M. extensor carpi radialis)

Thumb

Elbow extension (M. triceps)

Middle finger

C7/8 Triceps tendon reflex

Finger flexion (M. flexor digitorum profundus)

Small finger

Th1

Small finger abduction (M. abductus digitus minimus)

Medial elbow

Th5

Mamillae

Th10

Umbilicus

Hip flexion (M. iliopsoas)

Medial upper thigh

L1/2 Cremasteric reflex

Knee extension (M. quadriceps)

Medial thigh and knee

L3/4 Knee tendon reflex

Ankle dorsiflexion (M. tibialis anterior)

Medial lower leg

Great toe extension (M. extensor hallucis longus)

Great toe

Ankle plantarflexion (M. gastrocnemius)

Small toe and lateral foot

S1/2 Achilles tendon reflex

S3-5

Saddle anesthesia

S3/4 Bulbocavernosus reflex

Anal sphincter tension

Saddle anesthesia

S3/4 Anal reflex

Motor strength is quantified as described in Table 16.2.

Table 16.2

Muscle strength grading

0	Total paralysis
1°	Palpable or visible contraction
2°	Full range of motion with gravity eliminated
3°	Full range of motion against gravity
4°	Full range of motion with decreased strength
5°	Normal strength

Cord injury is assessed according to Frankel (Table 16.3).

Table 16.3

Classification of cord injury according to [1]

Type A	Complete	No motor or sensory function is preserved below the neurological level
Type B	Incomplete	Sensory but not motor function is preserved below the neurological level
Type C	Incomplete	Motor function is preserved below the neurological level and more than half of key muscles have a muscle grade <3
Type D	Incomplete	Motor function is preserved below the neurological level and at least half of key muscles have a muscle grade of 3 or more
Type E	Normal	Motor and sensory functions are normal

Alternatively, the ASIA (American Spinal Injury Association) classification can be used to assess the deficit.

ASIA classification of motor dysfunction:

0 = Total paralysis
1 = Palpable or visible contraction
2 = Full range of motion with gravity eliminated
3 = Full range of motion against gravity
4 = Full range of motion with decreased strength
5 = Normal strength
NT = Not testable

ASIA classification of sensory deficit, based on each dermatome:

0 = Absent
1 = Impaired
2 = Normal
NT = Not testable

Spinal shock is an acute, transient state of paraplegia or tetraplegia, flaccid muscle tone, absent reflexes, bladder overflow incontinence, paralytic ileus, etc., even in the absence of osseous injuries.
After an initial spinal shock, complete cord injuries turn into spastic plegia and hyperreflexia showing extensor/flexor reflex synergies and involuntary bladder incontinence.
Spinal cord lesions at the C-spine level are defined as tetraplegia:
- Ultrahigh tetraplegia are lesions above the C4-level, high tetraplegia between C4 and C6. The loss of thoracic respiration combined with a reduced vital capacity and decreased clearance of pulmonary secretion is what all tetraplegiae have in common.
- Paraplegia describes lesions of the spinal cord on the thoracic level with sustained functionality of arms and hands. High paraplegia is a lesion below C8 but above Th4 leaving the latissimus dorsi and trapezius muscles functional. Low paraplegia shows lesions below Th4. Tetraplegia and paraplegia both show complete loss of bladder and rectal control, the loss of sensory perception (pain/temperature, touch/spatial information) and loss of vegetative regulation (regulation of blood vessels, body temperature and functional impairment of organs).

16.1.7 Diagnostics

X-ray: a.p. and lateral
CT scan: image reconstruction allows for a detailed evaluation of fractured parts
MRI: to identify existing injuries to the spinal cord, spinal nerves, and ligaments

16.1.8 Treatment

The decision of whether to do a stabilizing/fusion procedure or spinal cord decompression is influenced by accompanying injuries and neurological symptoms.

The exact timing of an operative intervention as part of the treatment concept is of great importance.

Immediate intervention:
- Complete injury of the spinal cord (Frankel A)
- Incomplete but progressing injury (Frankel C)
- Paralysis after an interval without symptoms (Frankel B)
- Open spinal cord injury
Urgent indication for operative treatment within 6 h:
- Radicular neurological symptoms
- Cauda equina symptoms
- High-grade instability (Type B and C)
- Significant stenosis of the spinal canal (without neurological symptoms)
Elective indication for operative treatment within days:
- Closed nonreducible injuries
- Posttraumatic vertebral deformities (Type A)
- Traumatic disc injuries

16.1.8.1 Thoracic Spine Type-A Injuries

Nonoperative Treatment

End plate impaction (A 1.1)
Corpus collapse (A 1.3)
Nondislocated sagittal split fractures (A 2.1)

Operative Treatment

Dorsal Instrumentation (fusion):
- Incomplete burst fractures (Type A 3.1) showing wedging of >10° and <20°

Procedures

Dorsal or ventral instrumentation:
- After initial dorsal fusion of incomplete burst fractures (A 3.1) and burst split fractures (A 3.2), an additional ventral approach after CT-scan evaluation might be indicated. The decision as to whether to add ventral stabilization is influenced by the axial weight-bearing capacity of the affected vertebra, the remaining compression of the canal, the defect of the intervertebral disc’s pocket, and the degree of posttraumatic wedging (>20°).
- A combination of both procedures is usually indicated for complete burst fractures (A 3.3).