Moderately common symptoms (20 -70%, multiple studies)

Uncommon symptoms (<20%)

 Occasional reports

Classification of WAD

As the identification of specific pathology is highly problematical classification is usually based on symptomatology. Most commonly this is related to duration of symptoms, which are described as either acute or chronic. The QTF classification attempts to portray some level of the severity of symptoms resulting from a whiplash injury, table 2 (Spitzer et al 1995).

Table 2. QTF classification of WAD

Grade	Clinical presentation
0	No neck pain No mechanical signs
1	Neck pain, stiffness or tenderness only No mechanical signs
2	Neck pain AND Mechanical signs
3	Neck pain Mechanical signs AND Neurological signs
4	Neck pain AND Fracture or dislocation**

Mechanical signs = reduced movement, tenderness.

Neurological signs = sensory, motor, or reflex deficit.

** This group is obviously not for normal conservative management.

This classification scheme has been found to have prognostic value, in that higher grades have been associated with poorer outcomes at 6, 12, 18, and 24 months (Hartling et al 2001).

Epidemiology

Numerous studies have investigated the natural history of the effects of motor vehicle accidents. Difficulties exist in collecting such data in a way that has generalisability. In order to determine the prevalence of neck pain resulting from such accidents a study would need to find the prevalence of symptoms in a given sample of all accidents at a given place and time period. Few studies approximate to this model. Galasko et al (1993) looked at the incidence of neck sprain in those attending three Accident and Emergency departments (A & E) because of RTA on four different occasions between 1982 and 1991 (see table). Their data shows two distinct features – namely a dramatic increase in the proportion of those involved in RTAs developing neck sprain (not clearly defined) over the decade, as they term it, ‘a modern epidemic’. Secondly it is still less than half of those involved in accidents and who attend A & E departments who develop neck sprain.

Table 3. Incidence of neck sprain after RTA over 10 years

(Galasko et al 1993)

Year	Period	Number of patients injured in RTA	Incidence of neck sprain (%)
1982-1983	1 year	929	8%
1983-1984 (after seat belt legislation)	1 year	940	20%
1988	1 year	4319	31%
1990	6 months	2661	42%
1990-1991	1 year	6149	46%

Other sources also suggest that neck symptomatology is not universal following a road accident. A retrospective case note review from two separate years of a random sample of those attending an A & E department following an RTA was conducted. This was to investigate the role of legislation that had made the wearing of seat belts compulsory between the two dates (Thomas 1990). After legislation 52% were recorded as having no injuries, there was a reduction of all injuries but an increase in WAD, and out of 85 sampled only 13 (15%) had whiplash.  Freeman et al (1999) quote various government statistics from the USA – these report that there were five and a half million Americans involved in RTA in 1995, and that 53% of these include whiplash injuries. The information above would suggest that about half of those involved in car accidents, or even less, develop symptoms in the neck.

Most studies actually sample a group who attend health-care with neck pain said to be related to a recent vehicle accident. This may not include all those with neck pain, especially in the earlier studies. Data from other musculoskeletal problems, such as back or shoulder problems, relate that 50% or less of those with such symptoms seek health-care. It is unknown if the traumatic aspect of motor vehicle accidents makes this independence less likely. Any tendency of individuals to self-manage such neck pain may have been partially de-motivated in more recent years by the encouragement of the legal profession to seek compensation for their ‘injury’. Ultimately we cannot be sure that these studies represent all those with WAD, only those who have sought care. This group may be those with more severe symptoms, or those with greater anxiety concerning their symptoms; they may thus represent a biased sample more likely to be symptomatic at follow-up. If this were the case then a more pessimistic prognostic outlook would be presented than actually occurs in all those involved in accidents. In support of this perspective one report describes a few patients refusing participation in a study because they regarded the incident as trivial (Mayou & Bryant 1996).

Given the limitations of these studies their quality is improved if certain factors are incorporated in the design (Barnsley et al 1994, Freeman et al 1998). To study the natural history of a disease an unselected, inception cohort needs to be assembled at the outset of the study. The cohort needs to be of a reasonable size. Studies are unlikely to be representative if they only include patients who are studied simply because they are accessible to follow-up. Hospital based, rather than private practise, studies suffer least from possible sample bias, especially if drawn from the population attending the A & E department. However it cannot be known if others involved in car accidents never attended hospital.  The reports of consecutive patients are likely to be most inclusive, and high rates of follow-up are important to ensure valid statistics.

A population-based study from Canada followed nearly 3,000 individuals who had sustained a car crash and were receiving compensation (Harder et al 1998). About 20% recovered in a week and about 75% recovered in about 3 months; the median recovery time was 30 days, and 3% had not recovered at one year. However those without a police accident report were excluded from analysis, and recovery was measured by the last date of compensation. This is an indirect measuring tool for symptoms, likely to underestimate persistent complaints, and so this report is not listed.

Table 4. The prognosis of whiplash disorders

Reference	Country	Initial number of patients in sample	Setting	Follow-up	Follow-up time (mean)	Symptoms present at follow-up / control group
Hohl 1974	USA	534 no degenerative changes	Private orthopaedic office.	146 (27%)	5 years	43%
Deans et al 1987	Northern Ireland	175	A & E	137 (78%)	1-2 years	62%/7%
Pearce 1989	England	Unknown	Unknown	100	1/12 3/12 6/12 1 year	38% 29% 18% 15%
Hildingsson & Toolanen 1990	Sweden	93 consecutive patients	Hospital	93 (100%)	2 years	44% S+ 14% s
Norris & Watts 1983	England	61 consecutive patients	A & E	61 (100%)	2 years	QTF 1 44% QTF 2 81% QTF 3 90%
Gargan & Bannister 1990	England	61 consecutive patients	A & E	43 (70%)	10 years	40% S+ 48% s
Watkinson et al 1991	England	61 consecutive patients	A & E	35 (57%)	11 years	35% S+ 51% s
Squires et al 1996	England	61 consecutive patients	A & E	40 (66%)	15 years	42% S+ 27% s
Gargan et al 1997	England	50 consecutive patients	A & E	50 (100%)	3/12 2 years	33% S+, 38% s. 35% S+, 29% s.
Maimaris et al 1988	England	120 consecutive patients	A & E	102 (85%)	2 years	34%
Radanov et al 1991	Switzerland	104 consecutive patients	Referred by GPs	78 (75%)	6/12	27%
Pennie & Agambar 1991	England	152	2 A & E	144 (95%)	5/12	14%
Parmar & Raymakers 1993	England	204 144 traced	Medicolegal reports of consultant	100 (69%)	8/12 I year 2 years 3 years	50% 44% 22% 18%
Robinson & Cassar-Pullicino 1993	England	121 46 traced	Medicolegal reports of consultant	21 (46%)	8/12 13 years	81% 86%
Radanov et al 1993	Switzerland	164 referred consecutive patients	Referred by GPs	117 (71%)	Baseline 3/12 6/12	57% H 35% H 27% H
Radanov et al 1994	Switzerland	164 referred consecutive patients	Referred by GPs	117 (71%)	3/12 6/12 I year	44% 31% 24%
Schrader et al 1996	Lithuania		Police records, rear end, 1-3 years before.	Response 202 /240 (84%). Control: (63%)		35% 33%
Mayou & Bryant	England	74 consecutive patients	A & E	57 (77%)	3/12 1 year	51% 37%
Brison et al 2000	Canada	446 consecutive patients, 380 eligible (rear end, > 18 years)	2 A & E	88% at 6/12	Onset 1/12 3/12 6/12 12/12 2 years	61% S+ 51% S+ 37% S+ 35% S+ 34% S+ 36% S+
Hartling et al 2001	Canada		2 A & E	126 (75%)	2 years	QTF 0   9% QTF 1 29% QTF 2 47%

It can be seen that there is considerable variety of outcome across different studies. It is unknown if this reflects the natural variety of a heterogeneous disorder or in some way is a reflection of the different study designs. Prevalence rates of 30-40% one to two years after a car accident are quite common. Three reviews have investigated prognosis, only including the methodologically better studies, with a set of minimum quality criteria. Freeman et al (1998) selected 11 studies – these contained a total of over a thousand patients, with an average of 32 months follow-up; an average of 33% of patients still had symptoms. Studies accepted by the QTF show 27% to 66% still symptomatic at 6 months or more (Spitzer et al 1995). Barnsley et al (1994) found 8 studies fitting their criteria, which together indicated that between 14% and 42% develop chronic symptoms, and that approximately 10% will have constant, severe pain indefinitely. They considered the outcome to be dichotomous with resolution for the majority in the first few months, but for the minority indefinite persistent symptoms.

Examination of the figures in the table above by length of follow-up and quality of study does not essentially alter outcomes, but is not entirely logical either. Studies with a follow-up greater than one year give an average rate of symptoms of 60%, whilst those under a year give an average of 40%. Good quality studies give a prevalence of 68%, poorer quality studies of 43%. 

Clearly there is considerable individual variation in the natural history of WAD; it does not follow a uniform or a predictable course. For some it would seem the incident is very trivial, no or minimal symptoms ensue, and no or minimal health care is sought. For those who attend A & E many will improve in the first few weeks, and become asymptomatic within a month or so. However a substantial minority of those who seek health care will have persistent symptoms two or three months later – further improvements occur in this group, but recovery appears to be less and less likely the longer symptoms persist. Those with long-term symptoms may comprise at least a third of all those who seek help.

Prognostic factors

Various studies have tried to identify factors that are associated with persistent symptoms (Hohl 1974, Deans et al 1987, Hildingsson & Toolanen 1990, Norris & Watts 1983, Watkinson et al 1991, Maimaris et al 1988, Gargan & Bannister 1990, Hartling et al 2001, Stovner 1996, Allen et al 1985, Olney & Marsden 1986, Mayou & Bryant 1996, Pennie & Agambar 1991, Gargan et al 1997, Radanov et al 1991, 1994, Harder et al 1998). A wide range of potential prognostic factors has been considered in different studies. Simply because a factor is associated with persistent pain it cannot be known that it is causative. For certain factors the evidence is contradictory, and thus certain items appear in more than one column in table 5.

The strongest and most consistent factor associated with a poor prognosis is severe initial symptomatology. This is especially so if associated with headache, arm pain, neurological signs or symptoms, and restricted range of movement (QTF WAD 3).

Table 5. Prognostic factors in whiplash disorders

Factors associated with good outcome	Factors associated with persistent pain	Factors found not to affect outcome
	CLINICAL
	Arm pain**	Initial symptoms
Mild symptoms	Moderate to severe initial symptoms**	Previous NP
	Arm paraesthesia / numbness**	Arm pain
	Higher QTF grade*
	Limited ROM*	Limited ROM
	Scapular pain
Later onset pain	Immediate pain*	Time of onset of pain
	Neurological signs
	Back ache*
	Headache**
	X-ray findings**	X-ray findings
	Previous headache for subsequent headache
	THERAPY
	Collar > 12 weeks
	Home traction
	Resumption of therapy
	Hospitalisation following accident
	ACCIDENT
		Extent of property damage to car
	Wearing seat belt	Wearing seat belt
	Rear/front impact**	Type of collision**
	Passenger*	Position in car
		Head rest
		Severity of accident
	Truck or bus
	INDIVIDUAL
Younger age*	Older age**	Age
	Having dependents
	Women*	Sex**
	Not having full time employment
	Psychological response at 3 months	Baseline psychological variables**
	LITIGATION
Settlement of compensation	Litigation	Settlement of compensation*
		Litigation*

*/** = two/or more studies.

Baseline psychological variables do not predict future pain (Radanov et al 1991, 1994). One study that looked at psychological variables as defined by the General Health Questionnaire found that within a week scores were normal in 82% of the group. However in the group who developed persisting and intrusive symptoms at three months scores had become abnormally high in 81% of the patients (Gargan et al 1997). Outcome at two years was predicted both by these raised scores and restricted neck movement. These findings suggest that the disorder has both physical and psychological components, but the psychological response develops after the physical damage, and that these responses are established within three months of injury. Psychological features exhibited by these chronic pain patients would appear to be the consequences of somatic symptoms and not their cause (Wallis et al 1996, Radanov et al 1996).

A controversial factor is the role of litigation, but several studies discount the prognostic value of whether or not compensation is sought, and whether a settlement has been reached (Pennie & Agambar 1991, Mayou & Bryant 1996, Paramar & Raymakers 1993). As can be seen in table 5 the prognostic significance of litigation issues is not clear, with different reports finding contradictory conclusions.

Management of WAD

Maxwell (1996) investigated physiotherapy management of WAD by sending 72 questionnaires to 18 randomly chosen hospitals, from which there was a response rate of 68%. On initial examination physiotherapists most commonly used a Maitland approach (49%), and less commonly a Cyriax (20%) or McKenzie (18%) approach. A wide range of therapies was used, often in combination: mobilisation or mobilisation and exercise (100%), massage (45%), exercise only (40%), McKenzie only (40%), manipulation or manipulation and exercise (50%), mechanical or manual traction (90%), adverse neural tension techniques (50%), electrical modalities and posture advice (90%). Figures are estimated as results are only presented as a bar graph, and clearly show multiple interventions to be common. The proportion that used electrical modalities is not given, but the most commonly used are ultrasound, PEME, TENS, interferential, and short-wave diathermy. As in other areas of musculoskeletal medicine it would appear that physiotherapy management is something of a lottery with common usage of techniques and modalities for which there is little or no evidence.

A recent systematic review of conservative treatments for whiplash has been conducted (Peeters et al 2001). They found 11 studies that met their inclusion criteria, most of poor quality, which undermined their ability to draw conclusions. In 5 studies comparing rest and collar with activity, 4 favoured activity. They concluded that active treatments show a beneficial long-term effect, and that ‘rest makes rusty’. A review of physiotherapy management options for whiplash was made by Thacker (1998).

Logically the management of WAD should be considered in its acute or chronic stage. In the studies looking at interventions for acute WAD most patients were recruited within a few days of the accident, in one study (Provincilai et al 1996) recruitment was on average about a month since injury. Not all significant outcomes have been tabulated. As well as the results listed below, other statistically significant results supported the same outcome – these related to improved range of movement, areas of pain, neck stiffness, or patient assessment of change. In the table the intervention that is superior is underlined.

As far as acute whiplash is concerned the appropriate management is reasonably clearly delineated from the evidence (table 6). This should consist primarily of advice about normal activity, no or minimal sick leave, no use of collar, and a regular and progressive exercise programme starting with rotation and retraction. If with a general progressive exercise routine there is failure to improve then a McKenzie protocol should be instigated.

An active treatment approach is supported by numerous studies (Mealy et al 1986, McKinney et al 1989, McKinney 1989, Borchgrevink et al 1998, Soderlund et al 2000, Rosenfield et al 2000), and this is combined with a McKenzie protocol by Rosenfield et al (2000). Use of collars and rest lead to worse outcomes than active treatment (Mealy et al 1986, McKinney et al 1989, McKinney 1989, Borchgrevink et al 1998), or is no different to no collar (Gennis et al 1996). Mobilisation is better than collar and rest (Mealy et al 1986), but in the long term leads to worse outcomes than exercise and advice (McKinney 1989).

Traction, TENS, and ultrasound are ineffective (Pennie & Agambar 1990, Provinciali et al 1996). For pulsed electro-magnetic therapy (PEMT) or pulsed short wave one study found significant improvements over placebo at 2 and 4 weeks, but no difference at 12 weeks (Foley-Nolan et al 1992); another study found this ineffective as part of treatment package (Provinciali et al 1996). One study, not placebo controlled, found ultra-reiz current to be effective immediately after treatment; with less difference, though still significant, at 6 weeks (Hendriks & Horgan 1996)

Table 6. Intervention studies – Acute/subacute WAD

Reference	Patient Nos. (% follow-up)	Longest follow-up	Group 1	Group 2	Group 3	Differences
Mealy et al 1986	61 (84%)	8 weeks	Mobilisation & exercise	Collar, rest 2 weeks		Pain: 1: -4, 2: -2.5 (P<0.01). ROM: 1: +14, 2: +5 (P<0.05)
McKinney et al 1989	247 (69%)	2 months	1 off advice session on posture & movement	Multiple sessions physio	Rest 2 weeks	Pain: 1: -3.5, 2: -3.4, 3: -2.6 (1+2 v 3 P<0.01)
McKinney 1989	247 (68%)	2 years	1 off advice session on posture & movement	Multiple sessions physio		Pain: 1: 23%, 2: 44%, 3: 46%. (1 v 2+3 P=0.02)
Pennie, Agambar 1990	152 (89%)	5 months	Traction + exercise	Collar 2 weeks, exercise		Pain-free: 1: 81%, 2: 91% (NS)
Foley-Nolan et al 1992	40 (100%)	12 weeks	PEME collar	Placebo collar		Pain: 1: -5.2 2: -4 (NS)
Provinciali et al 1996	60 (NR)	6 months	Multi-disciplinary	TENS, US, PEMT		Pain: 1: -5.9, 2: -2.6 (P<0.001).
Hendriks & Horgan 1996	20 (70%)	6 weeks	Ultra-reiz Current + as 2	Ice + exercises		Mean pain difference: 3.2 (P<.005)
Gennis et al 1996	250 (78%)	6 weeks	No collar	Collar		No pain/ better: 1: 79% 2: 86% (NS).
Petterson et al 1998	40 (97%)	6 months	Oral steroid	Placebo		Mean sick days: 1: 4.7, 2: 51.7 (P=0.0097).
Borchgrevink et al 1998	201 (89%)	6 months	Act-as-usual	Collar + sick leave 2 weeks		Neck pain & headache:  1 v 2 P<.05 & P<.01
Rosenfield et al 2000	102 (86%)	6 months	1A: < 4 days. 1B: > 2 weeks. Rotation exercises, McKenzie protocol	2A: < 4 days. 2B: >2 weeks. Advice leaflet		Pain: 1A: -30, 1B: -15, 2A: +1, 2B: -7 (1 v 2 P<0.001).
Soderlund et al 2000	66 (53)	6 months	Neck care advice + mobilising exercises	As 1 + isometric exercises		Pain (10): 1: -1.7, 2: -2.5 (NS), Disability (70): 1: -6.4, 2:-10.6 (NS). (1+2 over time P<.001)

NS = no statistical difference.

US = ultrasound.

PEMT = pulsed electromagnetic therapy. 

NR = not reported.

Underlined intervention = statistical significance in favour of that intervention.

For chronic WAD the literature is generally so sparse and of such poor quality that it is impossible to use evidence to construct an appropriate conservative management strategy (table 7). Most trials relate to injection interventions. An uncontrolled study using a multidisciplinary functional rehabilitation approach reported significant before/after changes in pain, disability, and psychological factors (Vendrig et al 2000). Schofferman & Wasserman (1994) reported significant before/after changes in pain and disability using injections, NSAIDs, and stabilisation exercises, but again without a control group. Harding (1998) describes ways to try to minimise chronicity following whiplash, and Shorland (1998) describes management for chronic symptoms. This is a self-management approach using cognitive-behavioural concepts and exercise and planned activity.

Feine and Lund (1997) reviewed the literature on physiotherapy management of chronic musculoskeletal pain in general. No modality was shown to have a long-term effect greater than placebo, but treatment (including placebo) was always better than no treatment, with the more therapies included in the package the better the outcomes. In other words, whatever you do (active treatment or placebo) will help at the time and the more you do the better the response will appear to be, but the benefit will not outlast the giving of therapy. Only two of 22 trials reported significant long-term benefit; the intervention was exercise.

As in acute patients a mechanical assessment should be conducted. An unreduced derangement may be present requiring a specific directional preference of movement. Multiple direction dysfunctions also occur in this group, as a result of reluctance to move in the earlier stages of recovery. Failure to respond is likely to be high; poorer prognosis is more probable the longer symptoms have been present, and if previous unsuccessful therapy has been received.

Table 7. Intervention studies – Chronic WAD

Reference	Patient nos. (% follow-up)	Mean length of symptoms	Group 1	Group 2	Differences
Byrn et al 1993	40 (100% at 8 months	5 years	Tenderpoints injected with sterile water	Tenderpoints injected with saline	Pain: 1: -1.6, 2: +1.1 (P<0.001)
Barnsley et al 1994b	42 with ZJP (100% at 20 weeks)	39 months	Intra-articular injection corticosteroid	Intra-articular injection anaesthetic	Median time to return to 50% pain level: 1: 3 days, 2: 3.5 days (NS)
Fitz-Ritson 1995	30 (100% at end of treatment – 8 weeks)	> 12 weeks	Chiropractic + stretching / strengthening exercise	Chiropractic + “phasic” rotation exercise	Neck disability index: 1: -7% (P>.05), 2: -48% (P>.001)
Lord et al 1996b	24 with ZJP (100% at 1 year)	34 months	PRFN	Placebo PRFN	Median time to return to 50% pain level: 1: 263 days, 2: 8 days (P= 0.04)

Z = zygapophyseal joint pain established by response to double intra-articular anaesthetic blocks.

NS = not significant.

RCT = randomised controlled trial - the strongest level of evidence.

PRFN = percutaneous radio-frequency neurotomy.

Rejected studies: Su & Su (1988), Vendrig et al (2000), Schofferman & Wasseman (1994) – no control group.

Underlined intervention = statistical significance in favour of that intervention.

Summary

Although the existence of whiplash as a clinical entity is still debated in the medical community, both patients and clinicians largely accept it. WAD is the occurrence of neck pain and headache arising as a direct result of a road traffic accident – other symptoms occur with less frequency. Such neck pain does not always result from car accidents, available studies suggest that about 50% or less of those involved in accidents go on to develop significant neck symptoms. Of those who do develop neck pain the natural history is extremely varied and unpredictable. Whilst the majority appear to resolve their symptoms within the first few months; the rate of resolution then slows considerably, and a significant minority of patients will be left with persistent symptoms.  Numerous factors have been found to be suggestive of a poor outcome, but for many of these the evidence is contradictory. The most consistent factor across multiple studies associated with poor outcome is to do with severity and spread of symptoms.

Management of acute whiplash is dependent upon exercise, advice, and patient-centred care. The available evidence makes clear the importance of a return to normal activity and movement as quickly as possible. Regular repeated movements are essential, starting with rotation and retraction, to recover full range of movement. Posture correction and interruption of static postures are also important. A graded return to full activity should be supplemented by a full mechanical assessment to determine the presence of derangement and the need for a particular directional preference. In the absence of this a more general approach is required.  For chronic whiplash patients the evidence is much less convincing, and the possibility of persistent and unrelenting symptoms must be considered. Again an exercise, patient-centred approach is essential. Multiple direction dysfunction is not an unusual finding in those with chronic symptoms.

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