Whiplash describes a range of injuries to the neck caused by or related to a sudden distortion of the neck. The typical clinical picture in whiplash injury is that following the injury there is no obvious immediate pain.
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Whiplash - describes a range of injuries to the neck
1. Whiplash
Luc Peeters, MSc.Ost. (University of Applied Sciences)
Grégoire Lason, MSc.Ost. (University of Applied Sciences)
The International Academy of Osteopathy
http://www.osteopathy.eu
Whiplash describes a range of injuries to the neck caused by or related to a sudden
distortion of the neck. The typical clinical picture in whiplash injury is that following
the injury there is no obvious immediate pain.
In severe cases there may be initial stiffness of the neck. Initially function is not
impaired either. The patient may proceed from the accident to continue with daily
activities but begins to notice stiffness in the neck.
The following night is often uncomfortable and the majority develop significant pain
and stiffness by the subsequent morning.
This clinical picture varies considerably from patient to patient according to the
severity of the accident (trauma) and whether the patient has a vulnerable neck by
reason of pre-existing degenerative changes which may give rise to symptoms after
injury.
The whiplash mechanism consists of the following possible problems:
• Bending.
• Shear.
• Compression.
• Combinations.
Within a fraction of a second after impact from whiplash, adjacent vertebrae in the
neck flex and extend at different rates.
There appears to be a point at which the C5 and C6 vertebrae has a greater amount
of extension than any other segment.
This may excessively compress the facet joint and stretch the facet joint capsule.
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2. Impact C5
Overstretch
C6
Whiplash at level C5-6
Shortly after impact, the cervical spine undergoes what is called an S-shaped curve.
In this configuration, the cervical spine, rather than simply being curved in a normal
C-shape, as it would normally be at rest, takes on an altered shape: the lower part of
the cervical spine moves into extension and the upper part of the cervical spine
moves into flexion.
Hydrodynamic theory
The hydrodynamic theory involves the concept of pressure alterations inside the
spinal canal secondary to extension–flexion changes in the spinal curvature due to
rear impact accelerations.
The spinal canal lengthens and shortens in extension and flexion and this change in
length, which affects the pressure inside the canal, may traumatize the dorsal root
ganglia leading to whiplash-associated disorders.
Radiculopathy however is not the most common complaint in whiplash patients.
Muscular involvement
During the extension – flexion motion of the trauma, eccentric muscle contraction of
as well the anterior as posterior muscles can occur and cause muscular complaints.
The hyperextension mechanism of the injury is mostly accompanied with rotation that
exceeds the normal range of motion. This can cause mechanical damage as well as
damage to the vertebral artery.
The shear and compression hypothesis
The shear and compression hypothesis attributes neck pain to the stretch of the facet
capsule resulting from these two biomechanical variables.
In a rear impact, shear forces occur in the cervical spine because the forward motion
of the thorax occurs before the head motion. The shearing action imparts a relative
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3. motion between adjacent vertebrae, and this motion is the highest in the lower
cervical level because of the facet orientation.
In addition, compressive forces are generated early in the acceleration phase due to
the straightening of the thoracic spine.
In rear impacts, anterior shearing of the lower vertebra occurs, and its facet joint
offers little or no protection. This is in contrast to frontal impacts wherein the anterior
shearing of the upper vertebra occurs, and its contact with the facet joints provides
protection because of the anatomical orientation of these structures. Axial
compressive force does not exist in the frontal mode.
Let’s not forget that whiplash (rear, front or lateral) can cause damage to the brain.
Bleeding can occur on the opposite side of the impact to the head.
Psychological responses appeared to be within normal ranges soon after the
accident with the psychological distress seen later proposed to be as a consequence
of ongoing pain and disability.
Classification of whiplash injury (Quebec Task Force): WAD (Whiplash
Associated Disorders):
0 No complaint about neck pain.
No physical signs.
I Neck complaint of pain, stiffness or tenderness only.
No physical signs.
II Neck complaint.
Musculoskeletal signs including:
Decreased range of movement.
Point tenderness.
III Neck complaint.
Musculoskeletal signs.
Neurological signs including:
Decreased or absent deep tendon reflexes.
Muscle weakness.
Sensory deficits.
IV Neck complaint and fracture or dislocation.
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4. Summary of possible injuries:
• Facet joint cartilage damage.
• Disc tear, most often in the lower segments of the neck.
• Nerve root impingement with radiation along the affected nerve.
• Ligamentary tear (facet capsules, anterior and posterior longitudinal
ligaments,…).
• Muscle tear.
• Cerebral hemorrhage.
• Arterial dissection.
• Medullar overstretch.
• Dura overstretch.
• Dislocation.
• Fracture (rupture or impaction).
Patients after whiplash must be immobilized as soon as possible (collar).
From WAD stage III, X-ray is necessary.
Osteopaths shouldn’t treat locally too soon after the trauma because of the above
mentioned possibilities. Manipulations are contra-indicated and the major result
comes from immobilization and rest.
The structural damage of the whiplash can in a later stage of life cause chronic
cervical pain (ligamentary rigidity or hyperlaxity, facet arthrosis, disc degeneration,
cervical instability, arterial impairment).
Differential diagnosis in the case of whiplash injury is very important. Multiple
structures can be affected. Therefore it is difficult to give standardized treatment
options for the osteopath. A general rule however is not to treat locally too soon after
the accident. The injured tissues need time to heal by themselves and this can take
up to 3 weeks. Rest, eventually with collar is important in this perspective.
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