by: Ashley Nonemaker
Description
Whiplash or Whiplash Associated Disorder (WAD) is an acceleration-deceleration mechanism of energy transfer to the neck.1 A sudden forceful hyperextension of the cervical spine occurs first and is quickly followed by hyperflexion.2
Anatomy
The cervical portion of the spine allows for a large range of motion. While this is great for function it also places the cervical spine at a higher risk of injury. There are 7 cervical vertebrae (C1-C7) and 8 spinal nerves. The first two vertebrae have special names: C1 is the Atlas and C2 is named the Axis. C1 is the connection between the spine and skull and it articulates with the occiputal portion. This is labeled the atlanto-occipital joint which has slightly higher amount of flexion than C1-C2. The articulation between C1 and C2 is labeled atlanto-axial joint and has approximately 40 degrees of rotation occurring there. At these two joints there are not any discs and due to the abnormal shape of these vertebrae, stability relies greatly on the ligamentous network. The lower portion of the cervical spine (C3-C7) all are normally shaped and have intervertebral discs.
*Left Picture: Full Spine Lateral View, Right Picture: Cervical Spine Lateral View2
*Lateral view of Occipito-atlanto-axial Segment. 6-Dens of C2, 7-Anterior Arch of C1, 13- Occiput of Skull4
Incidence/Prevalence
The incidence of whiplash injury varies greatly between different parts of the world.1 Each year, approximately three million people experience whiplash injuries with only about half fully recovering. About 600,000 of those individuals will have long-term symptoms, and 150,000 will become disabled as a result of the injury.2 WAD is most commonly seen in male drivers between the age of 20 and 24 years and in passengers between the age of 15 and 19. Older age, female, neck pain on palpation, muscle pain, radiating pain and numbness down into the hands, arm and shoulder and headache are independently associated with a slower recovery.5
Clinical Presentation
A patient suffering from WAD can present with neck pain, headache (typically unilateral but sometimes bilateral), neck stiffness, shoulder pain, arm pain and/or numbness, paraesthesia, weakness, dysphagia, jaw pain, visual and auditory symptoms, dizziness and concentration difficulties.1,2,5 Patients' expectation of pain and type of compensation can play a role in presentation of long-term complaints.1 Headaches can typically last 4-72 hours, can be precipitated by physical activity, as well as be dull, diffused and throbbing.5 The main cause of the symptoms of WAD come from the tissues that may be injured in the cervical region.
These tissues include:
- anterior/lateral/posterior cervical muscle tear
- stelate ganglion of the cervical sympathetic chain
- articular cartilage fissuring
- facet joint sprain
- pars fracture
- intervertebral disc damage
- alar ligament/transverse ligament sprain or rupture
- adontoid peg fracture
- spinal cord/nerve root compression
- sternum/thoracic vertebrae/rib injury
- temporomandibular joint injury
- trauma to shoulders/wrists/knees/ankles/low back from impact
- head injury6
Potential Etiologies
Trauma is the main cause of WAD. It is most commonly caused from rear-end or side impact motor vehicle collisions. Diving may also be another cause.1
Diagnostic Tests
X-ray, CT or MRI can be used to access the damaged caused by WAD.7 MRI can be helpful in identifying partial or complete lesions of the alar ligament. Where plain film x-ray ad CT are most useful in identifying boney trauma- therefore less useful in minor whiplash injuries.5 Fracture and other major injury must be ruled out prior to any phyisical therapy treatment.
Evaluation/Special Orthopedic Tests
A thorough history should start out the evaluation; this should include a detailed recount of the traumatic incident. Information classifying MOI by direction of force, nature of impact and positioning of head/body at impact can help to determine the structures are injured. Another important history question is: did the symptoms come on right away or was a delayed onset? This condition should have a delayed onset of hours to days after the traumatic incident.7 Subjective information and presenting symptoms can be used to classify the severity of WAD using:
The Quebec Severity Classification of WAD7
Grade | Clinical Presentation |
---|---|
0 | No neck symptoms, no physical sign(s) |
1 | No physical sign(s), neck pain, stiffness, or tenderness only, neck complaints predominate, normal ROM, normal reflexes, dermatomes and myotomes |
2 | Neck symptoms (pain, stiffness) and musculoskeletal sign(s) such as decreased ROM and point tenderness, soft tissue complaints (pain, stiffness) into shoulders and back, normal reflexes, dermatomes, myotomes |
3 | Neck symptoms (pain, stiffness, restricted ROM) and neurological sign(s) such as decreased or absence of deep tendon reflexes, weakness (positive myotomes) and sensory (positive dermatome) deficits, x-ray shows no fracture, CT/MRI may show nerve involvement, possible disc lesion |
4 | Neck symptoms (pain, stiffness, restricted ROM) with fracture or dislocation, and objective neurological signs, possible spinal cord signs |
General observation of head, neck, shoulder as well as posture should be completed to determine if any abnormalities are present. ROM- active, passive and resistive should also be evaluated. If neurological symptoms exist distal to acromion process an Upper Quarter Neurological screening must be completed to determine the myotome, dermatome, and deep tendon reflex that could be affected. Joints in which symptoms radiate over should also be cleared. Palpation and joint play movements are also effective tools to access the type of injury. Special Tests will need to be used to rule in/out damage to the structures in the cervical spine. Tests which need to rule out specific conditions when indicated by subjective evaluation are:
- Vascular Signs
- Vertebral Artery Test
- Neurological Symptoms
- Spurling's Test, Distraction Test, Upper Limb Tension Test
- Cervical Myelopathy
- Rhomburg's Test, Babinski's Reflex
- Cervical Instability
- Transverse Ligament Stress Test, Anterior Shear Test, Lateral Shear Test, Lateral Flexion Alar Ligament Stress Test, Rotational Alar Ligament Stress Test
- Cervical Muscle Strength
- Craniocervical Flexion Test
- TMJ
- Anterior Guide, Lateral Glide, Medial Glide, Posterior Glide
Conservative Treatment
There is conflicting reports on initial treatment for acute WAD whether an active (therapeutic exercise) or passive (cervical collar) intervention is more beneficial. Two studies found that there was no significant difference in the amount of neck pain present six months post-injury between patients who had participated in physical therapy and those who had only rested using a soft cervical collar during the first 2 weeks after the WAD injury. It was found that patients who had continued with physical therapy had a significant amount of reduction of pain at six weeks and six months.1 Treatment that can be applied includes: ice/e-stim and NSAIDS to decrease inflammation, gentle cervical traction, active cervical ROM in a pain-free range to decrease the likelihood of neck hypomobility.8 The patient should receive activity counseling to encourage return to activity.5 A soft collar has not been proven to have long-term benefits but can be used as a tactile cue to prevent the patient from moving into painful end of range movements.1,5
Sub-acutely, pain management and cervical mobility should continue to be addressed. Cervical strengthening and coordination exercises should be started to increase stability that may be decreased due to the injured soft tissues. The focus of the strengthening technique should be endurance exercises and posture re-education. Manual therapies in addition to the therapeutic exercises have been found to increase efficacy. WAD can have psychological component so it is important to take the patient's beliefs, coping strategies, locus of control and disability in relation to ADLs into consideration.5
Modalities
In addition to the treatments listed above, there are different modalities that are appropriate in meeting the goal of pain relief. The application of modalities has the main goal of pain relief in conservative treatment of WAD because it is one of the main signs that present in the less severe grades for which conservative treatment is indicated. It is also important to treat pain because intensity of symptoms can be magnified by the patient's psychological perception of severity of pain to improve their prognosis.9 The amount and intentisty of pain that a patient experiences can also limit the amount of activity that they are willing to actively complete. If a patient does not move their neck due to pain it can lead to further complications of stiffness and loss of range of motion. The modalities that will be effective in pain management are as follows:
- Acute Whiplash Pain
- Pulsed electromagnetic therapy, traction, interferential electrical stimulation, massage, and cryotherapy9
- Chronic Whiplash Pain
- Transcutaneous electrical nerve stimulation (TENS), Ultrasound, pulsed electromagnetic therapy, traction, cryotherapy, thermotherapy, and traction9,10
Within the current research there is no definitive gold standard of modality application for WAD so these modalities should be applied at the discretion of the physical therapist. The most appropriate modality for the individual patient and their specific presentation of symptoms should be used. The best option is to apply one modality at a time, not to combine multiple modalities in one treatment session, to determine the effectiveness of the modalitiy on the patient's symptoms. The only exception can be when combining a modality with hot or cold therapy.
Surgery/Post-op treatment
If pain cannot be managed conservatively a radiofrequency cervical medial branch neurotomy can be done to relieve any joint pain still present. For remaining muscle spasm caused by the WAD can be injected with botulinum toxin.5 Surgery is not indicated for WAD grades 0-2, but may be indicated for grade 3 and grade 4. Surgery for grade 3 and 4 is dependent upon the severity of the disc lesion or fracture, respectively. If the trauma is great enough to dislocate the atlanto-occipital joint, long-term Halo Ring cervical traction accompanies surgical stabilization.5 Post-operative treatment will be followed through according to the protocol provided by the surgeon that is specific to the individual condition that the patient had surgery for- see additional resources.
Additional Resources
- www.apta.org
- http://www.mayoclinic.com/health/whiplash/DS01037
- http://my.clevelandclinic.org/disorders/whiplash/hic_whiplash.aspx
- http://www.eorthopod.com/eorthopodV2/index.php?ID=dbb85cd4171ee690cff1b8cc7b0a57c6&disp_type=topic_detail&area=3&topic_id=64f1e86c600e0a9569645ce1f2fdf4d5
- http://www.mayoclinic.com/health/radiofrequency-neurotomy/MY00947
- http://www.mayoclinic.org/movement-disorders/botox.html
- http://www.mayoclinic.com/health/herniated-disk/DS00893/PAGE=HD00011
- http://orthoinfo.aaos.org/topic.cfm?topic=a00414
- http://web.jbjs.org.uk/cgi/reprint/85-B/6/875.pdf