Whiplash Injury (Neck Strain/Neck Sprain): Causes, Symptoms, Diagnosis and Treatment

Whiplash occurs when a person’s head moves backward and then forward suddenly with great force. This injury is most common following a rear-end car collision. It can also result from physical abuse, sports injuries, or amusement park rides.

Whiplash Injury


Whiplash results when the soft tissues (the muscles and ligaments) of your neck extend beyond their typical range of motion. Your symptoms might not appear for a while, so it’s important to pay attention to any physical changes for a few days following any accident.

Whiplash is thought of as a relatively mild condition, but it can cause long-term pain and discomfort.

Some things that can cause whiplash include:
  • car accidents
  • physical abuse, such as being punched or shaken
  • contact sports such as football, boxing, and karate
  • horseback riding
  • cycling accidents
  • falls in which the head violently jerks backward
  • blows to the head with a heavy object
Whiplash Injury

Clinically Relevant Anatomy

Whiplash and whiplash-associated disorders (WAD) affect a variety of anatomical structures of the cervical spine, depending on the force and direction of impact as well as many other factors. Causes of pain can be any of these tissues, with the strain injury resulting in secondary oedema, haemorrhage, and inflammation:

Joints: zygapophyseal joints, Atlanto-axial joint, Atlanto-occipital joint
intervertebral discs and cartilaginous endplates
muscles

Ligaments: Alar ligament, Anterior atlanto-axial ligament, Anterior atlanto-occipital ligament, Apical ligament, Anterior longitudinal ligament, Transverse ligament of the atlas

Bones: Atlas, Axis, vertebrae (C3-C7)
Nervous systems structures: nerve roots, spinal cord, brain, sympathetic nervous system

Vascular system structures: internal carotid and vertebral artery
adjacent joints: Temporomandibular joint, thoracic spine, ribs, shoulder complex.

Whiplash Injury (Neck Strain/Neck Sprain)

Pathology

Most WADs are considered to be minor soft tissue-based injuries without evidence of fracture. 

The injury occurs in three stages:  

Stage 1: the upper and lower spines experience flexion in stage one
Stage 2: the spine assumes an S-shape while it begins to extend and eventually straighten to make the neck lordotic again.
Stage 3: shows the entire spine in extension with an intense sheering force that causes compression of the facet joint capsules.
Studies with cadavers have shown the whiplash injury is the formation of the S-shaped curvature of the cervical spine which induced hyperextension on the lower end of the spine and flexion of the upper levels, which exceeds the physiologic limits of spinal mobility. 

The Quebec Task Force classifies patients with WAD (whiplash), based on the severity of signs and symptoms, as follows: 

Grade 1: the patient complains of neck pain, stiffness, or tenderness with no positive findings on physical exam. 
Grade 2: the patient exhibits musculoskeletal signs including decreased range of motion and point tenderness.   
Grade 3: the patient also shows neurologic signs that may include sensory deficits, decreased deep tendon reflexes, muscle weakness.
Grade 4: the patient shows a fracture.  

Etiology

Whiplash-associated disorders describe a range of neck-related clinical symptoms following an MVA or acceleration-deceleration injury.  The pathophysiology underpinning this disorder is still not fully understood and many theories exist. Some of the symptoms are thought to be caused by injury to the following structures: 
  • Cervical Spine Facet Joint Capsule
  • The facet joints
  • Spinal ligaments
  • Nerve roots
  • Intervertebral discs
  • Cartilage
  • Paraspinal muscles causing spasms
  • Intraarticular meniscus.

Epidemiology

The most common cause of WAD is MVAs, but it also occurs as a result of sporting injuries and falls. A study by Holm et al suggested that the numbers reporting symptoms has grown increasingly in recent years; in their paper published in 2008 they suggested that the incidence in North Ameria and Europe is approximately 300 per 100,000 inhabitants. In the UK the introduction of the compulsory wearing of seatbelts in 1983, an initiative to save deaths on the road, actually led to an increase in the number of reported WADs in the years. It is also more common in women than men with almost two-thirds of women experiencing symptoms and several studies found that women tended to a slower or incomplete recovery.compared to men. 

Clinical Presentation

Whiplash-associated disorder is a complex condition with varied disturbances in motor, sensorimotor, and sensory functions and psychological distress. The most common symptoms are sub-occipital headache and/or neck pain that is constant or motion-induced. There may be up to 48 hrs delay of symptom onset from the initial injury.

Motor Dysfunction
  • Restricted range of motion of the cervical spine.
  • Altered patterns of muscle recruitment in both the cervical spine and shoulder girdle regions (clearly a feature of chronic WAD).
  • Mechanical cervical spine instability
  • Sensorimotor Dysfunction (Greater in patients who also report dizziness due to the neck pain)

Loss of balance

  • Disturbed neck influenced eye movement control
  • Sensory Dysfunction: Sensory Hypersensitivity to a Variety of Stimuli
Brain Related
  • Psychological distress
  • Post-traumatic stress
  • Concentration and memory problems
  • Sleep disturbances
  • Anxiety
  • Depression
Initial depression: associated with greater neck and low back pain severity, numbness/tingling in arms/hands, vision problems, dizziness, fracture
Persistent depression: associated with older age, greater initial neck and low back pain, post-crash dizziness, anxiety, numbness/tingling, vision and hearing problems

Degeneration of Cervical Muscles

Neck stiffness

Fatty infiltrate may be present in the deep muscles in the suboccipital region and the multifidi may account for some of the functional impairments such as: Proprioceptive deficits, Balance loss, Disturbed motor control of the neck.

Other Symptoms

The following symptoms may also occur
  • Tinnitus
  • Malaise
  • Disequilibrium/Dizziness
  • Thoracic, temporomandibular, facial, and limb pain
It is important to carry out thorough spinal and neurological examinations in patients with WAD to screen for delayed onset of the cervical spine instability or myelopathy. Whiplash can be an acute or chronic disorder. In acute whiplash, symptoms last no more than 2-3 months, while in chronic whiplash symptoms last longer than three months. 

Patients with acute WAD experience widespread pressure hypersensitivity and reduced cervical mobility. Various studies indicate that there can be a spontaneous recovery within 2-3 months. According to the Quebec Task Force of WAD (QTF-WAD), 85% of the patients recover within 6 months.

In addition, according to a follow-up study by Crutebo et al. (2010), some symptoms were already transient at baseline and symptoms such as neck pain, reduced cervical range of motion, headache, and low back pain, decreased further over the 6 months period. 

They also investigated the prevalence of depression and found that at baseline this was around 5% in both women and men, whereas post traumatic stress and anxiety were more common in women (19.7% and 11.7%, respectively) compared to men (13.2% and 8.6%). The majority of all reported associated symptoms were mild at both baseline and during follow-up.

Whiplash Injury (Neck Strain/Neck Sprain)

Evaluation

The Canadian cervical spine rules or NEXUS criteria are useful for the evaluation of cervical spine injuries in the emergency department. These criteria determine the need for imaging based on the mechanism of injury, physical presentation at the time of the accident, symptomatic presentation in the emergency department, as well as the physical exam. 

The NEXUS c-spine criteria recommend imaging if there is posterior midline cervical-spine tenderness,  focal deficits,  altered mental status,  intoxication or distracting injuries.

The Canadian c-spine rules define the need for imaging with patients greater than 65 years of age, dangerous mechanism of injury, paresthesia, midline tenderness, immediate onset of neck pain and impaired range of motion. 

Additional imaging such as MRI may be necessary for abnormal findings on CT to evaluate for cord injury.  Flexion and extension films can help rule out ligamentous injury.

Clinical Diagnosis

WAD can be diagnosed based on the mechanism of the injury and clinical presentation of the patient. There are no specific neuropsychological tests that can diagnose WAD. However, there are several psychological symptoms, as described above, that are associated with WAD. In addition, a whiplash profile has been developed with high scores on sub-scales of somatisation, depression and obsessive-compulsive behaviour in patients with WAD.

Differential Diagnosis

  • Cervical spine fracture
  • Carotid artery dissection
  • Herniated disc
  • Spinal cord injury
  • Subluxation of the cervical spine
  • Muscle strain
  • Facet injury
  • Ligamentous injury

Outcome Measures

  • Neck Disability Index
  • Visual Analogue Scale (VAS)
  • Pain Catastrophizing Scale
  • The Whiplash Activity a participation List (WAL)
  • Disabilities of the Arm, Shoulder and Hand (DASH) in persistent Whiplash
  • SF-36
  • Functional Rating Index
  • The Self-Efficacy Scale
  • The Coping Strategies Questionnaire
  • Patient-Specific Functional Scale
  • General Health Questionnaire (CHQ)

Examination

The assessment of individuals with WAD should follow the normal cervical examination.

Subjective

The subjective history should specifically include information about:
  • Prior history of neck problems (including a previous whiplash)
  • Prior history of long-term problems (injury and illness)
  • Current psychosocial problems (family, job-related, financial)
  • Symptoms (location + time of onset)
  • Mechanism of injury (e.g. sport, motor vehicle)

Objective

Physical examination is required to identify signs and symptoms and classify WAD according to the QTF-WAD.

Inspection and Palpation

During palpation, stiffness and tenderness of the muscles may be observed. These physical symptoms are present in grade 1, 2 and 3. Trigger points may also be observed in grade 2 and 3 WAD. The number of active trigger points may be related to higher neck pain intensity, the number of days since the accident, higher pressure pain hypersensitivity over the cervical spine, and reduced active cervical range of motion.

ROM Testing

In grade 1 WAD, there are no physical signs, so there will be no decreased ROM. In grades 2 and 3, a decreased ROM can be identified by testing the neck flexion, extension, rotation and 3D movements.

Neurological Examination

To distinguish grade 3 from grade 2, a neurological examination is needed. Patients with grade 3 have symptoms of hypersensitivity to a variety of stimuli. These can be subjectively reported by patients, and may include allodynia, high irritability of pain, cold sensitivity, and poor sleep due to pain.

Objectively, the results of the neurological examination are hyporeflection, decreased muscles force and sensory deficits in dermatome and myotome. These responses may occur independently of psychological distress. Other physical tests for hypersensitivity include pressure algometers, pain with the application of ice, or increased bilateral responses to the brachial plexus provocation test.

Management

Whiplash Injury

Education, resumption of normal activity, and mobilization exercises are generally the treatment of choice. 
Ultrasound has also been shown to relieve muscle pain for whiplash-associated disorders.
First-line treatments include analgesics, nonsteroidal anti-inflammatories, ice, and heat.

Other controversial analgesic measures include muscle relaxants, which have been shown to have some therapeutic effect in limited studies. 
Biofeedback has also demonstrated effectiveness when used in conjunction with other modalities in acute WAD. 
Injection of lidocaine intramuscularly was also found to relieve pain symptoms. 

Most treatments alone appeared to have moderate effectiveness with combinations of treatment measures improving efficacy and early mobilization consistently most effective.

Physical Therapy Management

The mainstay of management for acute WAD is the provision of advice encouraging return to usual activity and exercise, and this approach is advocated in current clinical guidelines.

Management approaches for patients with WAD are poorly researched.
Often patients do not fit into treatment categories due to multiple factors, and multiple variances which warrant individualised treatment approaches.
Whiplash-associated disorder is a debilitating and costly condition of at least 6-month duration.

The majority of patients with whiplash show no physical signs however as many as 50% of victims of WAD grade 1 & 2 will still be experiencing chronic neck pain and disability six months later. A substantial minority develop LWS (late whiplash syndrome), i.e. persistence of significant symptoms beyond 6 months after injury.

The combination of the injury with psychological factors eg poor coping style may lead to chronic WAD.

Acute Whiplash

  • Education provided by physiotherapists or general practitioners is important in preventing chronic whiplash and must be part of the biopsychosocial approach for whiplash patients. The most important goals of the interventions are:
  • Reassuring the patient
  • Modulating maladaptive cognition about WAD
  • Activating the patient
  • The target of education is removing therapy barriers, enhancing therapy compliance and preventing and treating chronicity.
  • For acute WAD verbal education and written advice are helpful (evidence exists that oral information is equally as efficient as an active exercise program).
  • A multidisciplinary programme is best for subacute/chronic patients, with a programme integrating information, exercises and behavioural programmes.

Different types of education include:

Oral Education: Provide oral education concerning the whiplash mechanisms and emphasising physical activity and correct posture. It has a better effect on pain, cervical mobility, and recovery, compared to rest and neck collars. Oral education could be as effective as active physiotherapy and mobilisation.

Educational video: A brief psycho-educational video shown at the patient's bedside seems to have a profound effect on subsequent pain and medical utilisation in acute whiplash patients, compared to the usual care.
Education and information given to the patient must contain the following information:
  • Reassurance that prognosis following a whiplash injury is good.
  • Encouragement to return to normal activities as soon as possible using exercises to facilitate recovery
  • Reassurance that pain is normal following a whiplash injury and that patients should use analgesia consistently to control this
  • Advice against using a soft collar
  • More studies are required for the type, duration, format, and efficacy of education in the different types of whiplash patients.

Different types of exercise can be considered for WAD
  • ROM exercises,
  • McKenzie exercises
  • Postural exercises
  • Strengthening
  • Motor control exercises.
  • Active treatment which consists:

Active mobilisation that is applied gently and over a small ROM, and which is repeated 10 times in each direction, also be given as homework
Home exercise programs in acute WAD including training of neck and shoulder ROM, relaxation and general advice, is sufficient treatment for acute WAD patients when used on a daily basis.

Strong evidence to suggest that exercise programs and active mobilisation significantly reduce pain in the short term and there is evidence that mobilisation may also improve ROM.

Spinal manual therapy is often used in the clinical management of neck pain. Systematic reviews of the few trials that have assessed manual therapy techniques alone concluded that manual therapy, such as passive mobilisation, applied to the cervical spine may provide some benefit in reducing pain.

Patients with grades 1 and 2 WAD showed good results in a multimodal treatment program including exercises and group therapy, manual therapy, education and exercise. At their 6 months follow-up, 65% of subjects reported a complete return to work, 92% reported a partial or complete return to work, and 81% reported no medical or paramedical treatments over 6 months

The use of a collar stands in contrast with what is indicated in most of the studies; activation, mobilisation and exercise. It is proven that early exercise therapy is superior to collar therapy in reducing pain intensity and disability for whiplash injury. Other studies also showed that exercise therapy gives better pain relief than a soft collar.

Chronic Whiplash

Chronic WAD results from a combination of the injury with psychological factors.

A multidisciplinary therapy with cognitive, behavioural therapy and physical therapy, including neck exercises is applied in management of Chronic WAD patients. It also gives positive results according to the reductions of neck pain and sick leave.

Behavioural therapy is used in the therapy as it decreases the patient’s pain intensity in problematic daily activities. ie adapt planning and treatment.

Exercise programs have a positive result in reducing pain in the short term. Exercise programmes are the most effective noninvasive treatment for patients with chronic WAD and coordination exercises should be added to the treatment to reduce neck pain.

In patients with chronic WAD, negative thoughts are a very important factor. Negative thoughts and pain behaviour can be influenced by specialists and physical therapists by educating patients with chronic WAD on the neurophysiology of pain.

Simple advice is equally as effective as a more intense and comprehensive physiotherapy exercise programme.

In a study Clinical Biomechanics of Posture Rehabilitation using mirror-image cervical spine adjustments, exercises and traction to reduce head protrusion and cervical kyphosis. After 5 months, the patient’s chronic WAD symptoms were improved.

Clinical Bottom Line

For the management of chronic whiplash, there is strong evidence that multidisciplinary therapy is effective. This therapy consists of an exercise program. Early mobilization is most effective when other more serious clinical pathologies noted on examination and imaging diagnostics have been ruled out.

Prognosis varies secondary to comorbidities prior to the injury, severity of WAD, age and socioeconomic environment.  Full recovery has been shown to occur in a few days to several weeks. However, disability can be permanent and range from chronic pain to impaired physical function.

Though cervical pain is the most common symptom, dizziness and/or headaches can be chronic, persistently reported symptoms. Chronic pain, subsequent interference with work, and physical function can cause loss of income and lifestyle.

Diagnosis and treatment of WAD are complex and associated with many complex issues.  Legal environment, prior injury, comorbidity, age, and defensive medicine all play roles in the management and outcomes.  There is a large variation in diagnosis and persistence of symptoms depends largely on legal culture or the ability to seek compensation for WAD.
Dr Rohit Bhaskar, Physio
Dr Rohit Bhaskar, Physio Dr. Rohit Bhaskar, Physio is Founder of Bhaskar Health and Physiotherapy and is also a consulting physiotherapist. He completed his Graduation in Physiotherapy from Uttar Pradesh University of Medical Sciences. His clinical interests are in Chest Physiotherapy, stroke rehab, parkinson’s and head injury rehab. Bhaskar Health is dedicated to readers, doctors, physiotherapists, nurses, paramedics, pharmacists and other healthcare professionals. Bhaskar Health audience is the reason I feel so passionate about this project, so thanks for reading and sharing Bhaskar Health.

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