Definition  The term "whiplash," used to describe an injury mechanism of sudden hyperextension (backward motion) followed by hyperflexion (forward motion) of the neck.  Hyperextension – is a result of acceleration. The lower part of the body accelerates forwards and the unstable neck cannot control the movement of the head which moves the neck into sudden extension as a result of the weight of the head.  Hyperflexion – is a result of deceleration. The neck continues to move forwards causing hyperflexion until the chin bumps the chest.

Patho-physiology While the time associated with a specific collision will vary, the following provides an example of the occupant and seat interaction sequence for a collision lasting approximately 300 milliseconds.  0 ms: Rear car structure is impacted and begins to move forward and/or crushes Occupant remains stationary No occupant forces  100 ms: Vehicle seat accelerates and pushes into occupant’s torso (i.e. central portion of the body in contact with seat) The torso loads the seat and is accelerated forward (seat will deflect rearward) Head remains stationary due to inertia  150 ms: Torso is accelerated by the vehicle seat and may start to ramp up the seat Lower neck is pulled forward by the accelerated torso/seat The head rotates and extends rapidly rearward hyper-extending the neck  175 ms: Head is still moving backwards Vehicle seat begins to spring forward The torso continues to be accelerated forward The head rotation rearward is increased and is fully extended  300 ms: Head and torso are accelerated forward Neck is “whipped” forward rotating and hyper-flexing the neck forward The head accelerates due to neck motion and moves ahead of the seat back

Causes and Risk factors  Common causes : MVA / Sport injuries e.g. diving & contact sports(rugby) Degeneration in the articular complex.  Risk factors:  Whiplash pain/symptoms persisting beyond 6 months (43% failed to recover on average)  Significant ligament, disc, nerve, or joint capsule injury. -Passive instability—the ligaments of the neck are loosened, making it more susceptible to whiplash pain -Dynamic instability—the nervous system disruption causes a disturbance in the body’s natural muscular response to common, everyday forces.  Delay in initiating treatment

Causes and Risk factors cont.  Occupant age over 65  Occupant in a small car  Alcohol intoxication at time of MVA  Pre-existing degenerative changes  Prior whiplash injury  Prior cervical spine fusion

Signs and Symptoms  Acute Pain during rest especially if structures are placed on stretch as a result of oedema. Pain through entire ROM. Muscles are painful during stretch and contraction. Ligaments are painful when placed on stretch, except the interspinal ligament which is painful during extension.  Pain and tenderness on palpation over structures.  Referred pain as a result of : - irritation of a nerve-root - active myofascial trigger points - sclerotome referral (deep burning pain in the bone itself)

Signs and Symptoms cont.  Tenderness on palpation over spinous processes.  Neck muscle spasm with decreased cervical lordosis.  Headaches, especially occipital, temporal, frontal and retro-orbital, experienced as a deep pressure with pounding, nausea, vomiting, and photophobia.  Normal ROM restricted as a result of pain and muscle spasm.  Dysphagia as a result of oesophagus and pharyngeal trauma with hoarseness during the acute phase.  Sympathetic signs: intermittent weak vision, headache, dizziness, Horner’s Syndrome etc  Oedema

Signs and Symptoms cont. Other:  anterior chest pain: presents with angina, worsens with exercise and/or coughing & sneezing Associated symptoms: Thoracic outlet syndrome with intermittent compression on the brachial plexus - TMJ injury as a result of hyperextension Psychosis symptomatic of chronic pain:  Depression  Anxiety  PTSD

Possible Pathological Changes  Ant.,Post. and interspinal ligament injury  Disc herniation in severe cases  Fracture of the spineous process and vertebral bodies  Tear of the neck muscles  Oesophageal haemorrhage  Concussion  Vertebral Artery Damage

Medical management  Acute  Total bed-rest may be required for the first 2-3 days  Supportive, soft neck-support may be worn both day and night, only when the patient is in an upright position  The above mentioned encourages healing of the soft tissue  Ice for the first 24 hours  Heat is contra-indicated in the first 48 hours since it might cause haemorrhage of the soft tissue. It may be used afterwards, especially damp heat  Anti- inflammatory medication and muscle relaxants are prescribed  Careful, active non-weight bearing exercises may commence, except rotation and lateral flexion

 Sub-Acute  Muscle spasm and pain are less and the symptoms become more specific.  Wean from neck support. Still use it in a vehicle or when neck feels tired  Ultra sound and damp heat/ice  Mobilisations-short of pain  Cautious isometric exercises for instability  Increase active exercises and introduce flexion and extension exercises into the programme. Commence with PNF- patterns if patient’s pain will allow it.  Cautiously commence with distal neural mobilisations

 Chronic  Treat according to signs and symptoms  Pain at end of range; 6-8 weeks after injury  Totally wean from neck-support  Isometric exercises are progressed into standing  Evaluate for muscle imbalance and treat accordingly  Mobilise by stretching at the end of the range of movement(IV*), also make use of the combined movements and neural mobilisation techniques for final rehabilitation Continue with treatment until treatment reaches a plateau. The patient must then only come in for follow-up visits.

Treatment  Analgesics  Anti- depressants  Surgery  Psychiatric Treatment

Illustrations/ X-rays

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References  neck-pain.html neck-pain.html  health.com/conditions/neck-pain/factors- affecting-whiplash-injury health.com/conditions/neck-pain/factors- affecting-whiplash-injury