When Only a Pain Expert Will Do

5 Sep 2019

The International Association for the Study of Pain defines pain as “an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage (1)”, writes Dr Chris Jenner, medico legal pain expert. Pain is always subjective and we learn to apply the word to experiences related to injury in early life. Therefore, pain is an experience that we associate with actual or potential tissue damage. While it is a physical sensation experienced in a specific part of the body, it is also always unpleasant and thus there is often an emotional element to the condition (1). The concept of pain actually covers a wide spectrum of disorders, including acute pain, chronic pain and cancer pain, or a combination of any of these. It can arise for many reasons, including injury, nerve damage, surgery and metabolic problems such as diabetes. Sometimes there is no obvious cause (2).

A pain expert is a doctor who has undergone further training in order to gain a specialised knowledge in the evaluation, diagnosis and treatment of all different types of pain. In the UK, this training is provided by the Royal College of Anaesthetists. A pain expert will have an in-depth knowledge of the physiology of pain and be able to evaluate claimants, either for their own case or for the defendant, especially in the case of complicated pain conditions. In recent years, there have been many advances in the understanding of pain and an expert in pain medicine may be able to diagnose and explain a claimant’s pain condition in layman’s terms, providing an explanation for symptoms that have previously been viewed as arising from exaggeration, functional overlay and a desire for secondary gain (3). This level of indepth knowledge and insight is particularly helpful for legal teams and ultimately the court in reaching a judgement.

Along with an understanding of the specialised tests available to diagnose painful complaints, a pain specialist is able to prescribe appropriate medication and skilfully perform complex procedures, such as nerve blocks, spinal injections and other interventional techniques, which together may form the treatment plan for a patient suffering with pain. He or she is also responsible for coordinating any additional care to support the patient, such as physical or psychological therapies, and rehabilitation programmes, so that claimants receive a comprehensive and effective treatment plan for their condition (2).  When acting in a medicolegal case the pain specialist is able to offer an opinion on causation and prognosis to assist the legal team in reaching decisions on quantum.

The value of litigation cases is generally dictated by the type of injury suffered by the claimant and this can usually be determined by objective means (4). However, this is not true of pain conditions. As already discussed, pain is a subjective experience and there are no reliable tests to determine its presence or quantify it. Usually, the only way a doctor can gauge the severity of a claimant’s pain is by assessing the impact it has on their functionality (5). Furthermore, pain conditions such as Complex Regional Pain Syndrome (CRPS) are very rare and it is possible that courts may be unaware or sceptical of their existence. For a non-medical person, it can be difficult to believe that a seemingly innocuous accident or injury can cause such potentially devastating symptoms as happens in cases involving CRPS, and many cases may be dismissed if the court believes that the claimant is exaggerating or fabricating their condition (6,7) without input and explanation by an expert in this specialist area of medicine. Medical causation is critical in these cases and as the legal teams involved obviously do not have the medical expertise to answer or resolve the complex issues involved in these cases, an expert witness is needed. However, it is important to remember that the role of the expert witness is to provide a neutral opinion and this overrides any duty to the instructing party. In a simple case where a complete recovery is expected in a relatively short time, a report from a GP or orthopaedic surgeon may be sufficient to allow a settlement to be made. However, in many cases the continuation of pain is difficult to explain or becomes confounded by psychological factors to such an extent that the original cause is less significant (8). At this point, it is prudent and often necessary to call upon the expertise of a pain consultant.

In pain-related cases, it is often the situation that much of the available evidence is subjective and based on the claimant’s own statements about their condition (3,4). Diagnosis of the symptoms is often difficult and subject to a wide range of medical opinions, and any particular diagnosis may be controversial. In the past, chronic pain was often viewed as a psychological condition, but nowadays cases with a purely psychiatric origin are thought to be extremely rare (7,9). There may, however, be accusations of exaggeration of symptoms or malingering. Given that pain management is a narrow and specialist field, it is likely that only a pain expert will have the sufficient expertise and be familiar enough with the supporting medical literature to provide an accurate diagnosis and present a compelling case both in their report and in court. However, due to the complicated nature of such conditions, it is likely that the pain expert will be only one part of a team of experts from different disciplines, such as orthopaedics, rheumatology and psychiatry, that are required in order to obtain an accurate picture (9,10).

By instructing an expert witness, any party involved in litigation can ‘test the evidence’, which normally takes the form of a meeting between the client, expert, solicitor and barrister. This procedure can give a better awareness of the strengths and weaknesses of any particular case and it may help to uncover any other existing medical issues which may have a bearing on the case. It can be especially helpful in allowing the legal teams to satisfy themselves that the claimant’s current symptoms can indeed be linked to the original accident or injury; therefore the pain consultant will play a crucial role in this process. From this, the parties should be able to focus on the disputed aspects of a case and negotiate a fair settlement (11).

Once a pain expert has been selected, he or she will need to examine all of the claimant’s medical records before an opinion on causation can be offered in the medico legal case. While the claimant may feel that the problems they are currently experiencing result solely from the disputed incident or injury, careful analysis of the medical records may elicit other potential causes for the symptoms. The claimant’s medical history before the index event or injury can be vital in reaching a conclusion (4,12). For chronic pain cases, any entries indicating previous episodes of longer-term pain will be of particular interest, especially if there is no obvious reason, such as infection in a wound, why the pain persisted for longer than would normally be expected for the type of injury.

The expert will also be looking for any other information which will help them to form an opinion about the causation and prognosis of the claimant’s symptoms. This might include reference to a wide range of previous conditions which have the potential to influence how an individual responds to pain. In particular, any indication of somatisation, which reflects a tendency for stress to manifest as physical symptoms and illnesses, may be particularly relevant (12). This can be particularly important for a defendant, such as an insurance company, who is only required to compensate for the effects of an accident or injury. If a court decides, based on the evidence of a pain expert, that the claimant would have suffered similar problems in any case, the compensation payable will be limited (6,13). This point is illustrated by the findings of a review and analysis of judgements in pain-related cases undertaken in Korea. One important reason for the court to attribute a low degree of disability and thus reduce the compensation due was that the causal relationship between the injury and symptoms could not be completely proven due to the presence of pre-existing conditions. In one reported case, the court chose to place more weight on one expert’s report than another’s because “it made a more objective evaluation of the claimant’s physical condition, including calculation of pre-existing conditions attributing to the loss of the ability to work (6).”

Claims involving chronic pain conditions are often more complex and difficult than other cases involving serious injury. In addition to lengthy and expensive treatment, this type of claim can include future loss of earnings for years to come, and this factor often forms the largest part of any compensation awarded (4). Chronic pain cases are critically dependent on the skill and plausibility of the expert witnesses and the outcome of a case will often hinge on whichever expert’s view is accepted by the court. Thus, the selection of the correct expert from the outset of a case is crucial.

About Dr Chris Jenner

Dr Chris Jenner - medico legal pain expert


Dr Chris Jenner MB BS, FRCA FFPMRCA is a Consultant in Pain Medicine and leading expert witness in all medico legal cases which involve pain. Since 2001 he has been practicing at Imperial College NHS Trust as a Consultant at St Mary’s in Paddington, London and is an Honorary Clinical Lecturer for the Trust. He has a Pain Clinic at Charing Cross Hospital in London. Dr Jenner founded The London Pain Clinic in Harley Street London W1, where he is Clinical Director. He can be instructed through Medicolegal Partners Limited on 020 7118 0650 or info@medicolegal-partners.com. www.medicolegal-partners.


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