ANÁLISIS DEL MERCADO

The negative effect of compensation (or, more loosely, any secondary gain) on outcome after injury is not a recent phenomenon. Numerous historical accounts exist, and specific conditions which demonstrate this association are discussed in more detail later in this chapter.

There is some common ground between the effect of compensation on outcome and the effect of occupation on outcome, particularly since the introduction of workers’ compensation. One of the earliest recordings of how outcome may be influenced by occupation (rather than compensation) is attributed to Dupuytren, who was quoted in a thesis published in 1836.15 He compares the outcome of soldiers injured in battle to labourers, farmers or artisans: the latter having “a profound sorrow, a dark hopelessness”.16

Paradoxically, although others, like Dupuytren, have found that soldiers

injured in battle have been shown to have less pain and suffering compared to civilians with similar injuries,16 17 it is in soldiers that the earliest reports of illness related to compensation are found. The term “shell-shock” from World War I refers to illness related to conditions of battle. Similar reports from earlier conflicts can be found. In the American Civil War, this condition was referred to as “soldier’s heart” or “neurasthenia”,18 the latter being a term used in the 19th Century to indicate exhaustion of the nervous system.19 The

condition was initially attributed to physical injury, usually on some part of the nervous or cardiovascular system, caused by the physical effects of gunfire or gas.20 Lack of physical evidence, and possibly the concomitant rise of

psychiatry and psychology, led to these war-related conditions being labelled as psychogenic in nature after World War I.

In World War II, a similar condition was seen, although this time labelled as “battle fatigue”20 or “battle neurosis”.19 It was in World War II that it became clear that the development of this condition was not related to the degree of exposure to the conditions of battle, and that many soldiers diagnosed with battle fatigue were uninjured or had not been exposed to gunfire. Of further interest was the fact that the incidence varied with such factors as unit morale, effectiveness of leadership, and secondary gain.21 The role of secondary gain was widely accepted19 but, as is the case today, the form of secondary gain often varied, and included not only financial gain but also non-financial gains from assumption of the sick role. In another similarity with current debates, it was not known whether secondary gain actually caused the condition, or only prolonged or exacerbated an underlying condition.

The condition of battle fatigue was considered a form of post-traumatic neurosis but it was not until after the Vietnam War that the condition was labelled post-traumatic stress disorder. Since 1980, post-traumatic stress disorder has been given the legitimacy afforded by the Diagnostic and Statistical Manual of Mental Disorders (DSM), although, like the diagnoses it replaced, its legitimacy has been questioned.22

Historically, many other forms of post-traumatic neuroses have been reported, often associated with secondary gain. Probably the earliest widely reported form of post-traumatic neurosis related to compensation was “railway spine”. This was the name given to the widespread finding of chronic back pain and disability associated with railway injuries in the mid and late nineteenth century, mainly in England.

Railway spine was characterised by a variety of physical disorders attributed to a railway accident, in patients with no significant organic injury. The

symptoms varied and included back pain, limb pain, headache, fatigue, dizziness, memory loss, and sensory changes and weakness in the limbs. At the time, the mechanism for the condition was still thought to be organic, but without identification of an organic process, theories developed which

matched the thinking of the time. The condition was thought to be a form of neurasthenia: irritation of the nervous system secondary to the physical shock of the accident. Various terms were used for this such as spinal concussion, traumatic neurosis and nervous shock.19

In the nineteenth century, neurosis, neurasthenia and nervous shock were seen as physical disorders of the nervous system, separate to mental or emotional shock. Although the mechanism was thought to be through the physical impact of the collision, some element of exaggeration was suspected in claims for railway spine.23 Later, near the end of the nineteenth century, psychological theories were developed for conditions such as railway spine and shell shock.

Whatever the mechanism behind railway spine, the association with compensation was indisputable. By validating the physical nature of the disease (albeit with theories only), the medical community smoothed the way for sufferers to successfully sue the railway companies and by the 1860’s the railway companies were paying out large sums in compensation for this condition and were losing almost every personal injury case that went to court.24 25 The difficulty with assessment of the cases (due to lack of physical evidence of injury) was noted at the time and, interestingly, a proposal for an independent review panel, consisting of physicians, surgeons and a legal advisor was suggested, similar to solutions proposed and implemented for compensation cases today.23 When the theories regarding aetiology of the condition turned towards psychological factors rather than physical, claims became harder to support and the reporting of railway spine subsided.

Similar conditions, which pre-date railway spine, are less well documented. Steel nib syndrome was the earliest recorded epidemic of writer’s cramp and was reported as occurring among male clerks of the English Civil Service in the 1830s. It was attributed to the introduction of new technology (the steel nib). Like other traumatic neuroses, regional variations in incidence occurred, and a relationship between use (or overuse) of the limb, and symptoms, could not be established. Reynolds, in 1869 noted that symptoms of steel nib

syndrome could be developed by close contact with other cases and that the development was related to aspects of the will and described the “secondary influence the brain has over the relations established in the body”. Similarly, Gower noted in his monograph Diseases of the nervous system, that writer’s

cramp “is a disease easily imagined by those who have witnessed the disorder”.26

Steel nib syndrome was, however, only one form of a disorder termed writer’s cramp (or scrivener’s palsy). Other forms occurred, often named after the occupation in which the condition was seen, for example hammerman’s palsy, milker’s cramp and tailor’s cramp. Like steel nib syndrome, telegraphist’s cramp was blamed, by some, on new technology: the introduction of the telegraph (and accompanying Morse code key) in the late nineteenth century.27 28

Any connection between these early occupational upper limb disorders and compensation, however, is not well documented, as many of these conditions pre-dated the introduction of the workers’ compensation system. The

conditions were, however, used as bargaining tools in negotiations with employers and governments. In Britain, workers successfully lobbied the Industrial Diseases Committee to have telegraphist’s cramp listed on the schedule of compensable diseases in 1908, so that it would be covered by recently introduced workers’ compensation. There is evidence that the provision of compensation increased the incidence (or at least the reporting) of this condition. By 1911, telegraphist’s cramp was epidemic in Britain, and attempts to control it using regular rest breaks or different machines were largely ineffective.27 The study of this condition was interrupted by the development of wireless communication and the telephone but it showed

similarities with previous work-related upper limb conditions, and those that followed.

One of the earliest work-related conditions with detailed reporting and a strong link to compensation was condition known as miner’s nystagmus. Miner’s nystagmus was another example of a condition with few physical signs (even nystagmus was not necessary for the diagnosis), and which relied on patients’ symptoms for diagnosis. Like shell shock and railway spine, it involved many symptoms, including headache and fatigue. It was initially thought to be due to poor lighting conditions in coal mines. Present from the 1890’s to the early twentieth century, it was clearly used as a bargaining tool between workers and their employers, and compensation and secondary gain were implicit in the negotiations.29

Although it can be argued that these conditions were associated with

secondary gain through their use as negotiating tools, the clearest evidence of (financial) secondary gain in these conditions was usually from one of two sources: litigation through the court system (such as in railway spine), or benefits through the worker’s compensation system (such as in miner’s nystagmus).

Worker’s compensation dates back to the second half of the nineteenth

century when the introduction of workmen’s accident insurance spread across Europe from Germany.30 It was not adopted in the United States (state by state) until the turn of the century, and only under the condition that the

employers would be exempt from litigation under common law, and that costs could be passed on to the consumer. Worker’s compensation was introduced in New South Wales in 1926 through the Workers Compensation Act.

More recently, Repetitive Strain Injury (RSI), a condition that bears similarities to the upper extremity occupational disorders already discussed, has been extensively studied and shown to have a strong connection with the workers compensation system.31-44 It is of particular interest due to its high prevalence in Australia.

The incidence of RSI rose rapidly in the mid 1980’s, particularly in Canberra and Sydney.31 38 The condition was diagnosed through subjective complaints from the patients, as there were no tests available and no discernable

underlying pathology, despite some theories regarding inflammation and nerve injury. At the time, it was attributed to the introduction of the computer keyboard, which replaced the typewriter in the 1980s. As computers allowed faster keystrokes than a typewriter, it was felt that the increased typing speed caused an injury to the structures in the hand and wrist.31

It is interesting to note the similarity between RSI and writer’s cramp in that they appeared to be transmitted by line-of-sight. That is, the incidence of both diseases was largely confined to groups of workers, usually in one building or company, which led to theories relating to hysteria,31 employee-employer relations28 and malingering.41

Like many other conditions associated with compensation such as those already discussed, or whiplash, which will be discussed in detail later, physical theories have been put forward, but none were proven or widely accepted. Like these other conditions again, though, RSI was thought to be associated with many psychosocial factors. Tertiary gain by health professionals,

including doctors, physiotherapists and occupational therapists, all of whom stood to gain from having RSI established as a medical, and work-related condition, was thought to be a contributing factor. The union movement concern (which resulted in workplace lectures and publications such as “The sufferer’s handbook”) and misinformation and exposure in the media were also thought to contribute.28 As an example, one alarmist media headline at the time read: “Hi-tech epidemic. Victims of a bright new technology that maims”,45 another read: “A crippling new epidemic in industry”,46 and still others used words such as “torture”, “plague”, and “kills”.39

Although RSI reached epidemic proportions in the 1980s in Sydney and Canberra, compensation for the condition was eventually denied due to the lack of physical evidence of a disease process, combined with epidemiological evidence of the condition occurring in distinct clusters, and being unrelated to workplace conditions such as the typing speed or the number of keystrokes used.32 39 The strength of the association with compensation is best

demonstrated by the rapid decline in the incidence of the condition after claims for compensation were rejected.28

The relationship between compensation and illness is not new, and this historical review provides information regarding common features of illnesses that have been associated with compensation apart from the presence of secondary gain: the lack of a physical basis to support the diagnosis, and the geographic clustering of cases.

The next section covers the literature relating to specific conditions, and this is followed by a review of the literature pertaining to the effect of compensation on health in general and the possible mechanisms by which compensation may affect aspects of health.