Example: Despite surgical reconstruction and internal fixation, a 30 year old male has a total hip replacement (THR) two years after severe acetabular fracture with central dislocation. He later initiates a personal injury claim against the driver of the vehicle that struck him.
What do you need to consider as an orthopaedic expert in the Court case when talking about the prognosis of this (or in principle, any other injury)?
Approach 1. You quote survivorship for the type of implant used, depending on the fixation (cemented/cementless) and bearing surface (ceramic/poly, ceramic/ceramic, metal/poly etc). These figures are obtained from papers or a registry.
Approach 2. You take the usual survivorship of THR after acetabular fracture, and give those figures.
Approach 3. You take the literature relating to the survivorship of THR in acetabular fractures; noting the factors that positively or negatively affect prognosis; noting the range of outcomes. (Even better would be outcome data gleaned from National Joint Registry, though at the time of writing the NJR UK does not have an analysis relating to THR survivorship after acetabular fracture). If the patient has particular features of positive or negative prognostic significance, you state what they are and incorporate that in your estimate of the likely outcome in each reasonable scenario for that patient. What results from this analysis is a personalised estimate of the risks, illuminated by reference to the literature, but which recognises that the mean or median of a group is not the same as the prognosis for this individual.
Under Practice Direction 35 an expert should consider all material facts, including those which might detract from their opinions. So as an expert you need to go the full mile in your analysis, and can’t stop at either approach (1) or (2), because your analysis is incomplete if it does not assist the Court to determine the outlook for that particular individual.
You should not edit the literature so as to present only those papers that support your opinion. The Court wants a balanced view to be presented, not a biased one. You can explain the reasons why you prefer one paper over another when forming your opinion. It assists the Court to see how you came to your conclusion on important points. A cross-section of meaningful papers is enough; reproducing every paper published on the topic is unnecessary & unpopular!
If your analysis does not attempt to place the individual within the Bell curve or range of possible outcomes with some accuracy, then your opinion could have unintended consequences.
In this example, if the Claimant will be on the 25th centile of function or hip replacement longevity (due to poorer prognostic features), but you say they should be on the 50th centile of function or longevity, then if the Defendant is liable, it only pays for the loss of 50%, instead of the actual 75% loss.
If on the other hand the Claimant has good prognostic features and should be on the 75th centile of function/longevity, but you say they are on the 50th centile of function/longevity, vice versa this favours the Claimant.
Approach (3) is the correct one in the context of litigation. What is required is a report which comprehensively assesses the body of literature and range of practices available, considering all material facts and coming to an objective, unbiased and reasoned opinion.The duty of an expert is to help the court on matters within their expertise. Ultimately the judge will decide whether she prefers your evidence and body of expert opinion, or your counterpart’s.
The problem here with approaches (1) & (2) is that in this example we are looking at a patient who is not typical of the overall groups that are reported in the literature. His result is probably therefore going to be either better or worse than the overall figure. The UK National Joint Registry report 2018 contains records of nearly a million hip replacements; 60% of patients undergoing the procedure are women. The mean age is 68 years. In this example, the patient is male, less than half that age, and in other respects is a fit young man. Thus he is almost entirely unrepresentative of the typical osteoarthritis THR patient.
If you were the treating specialist of that young man, you would be required to explain all the reasonable treatment options (the definition of a reasonable treatment option has been defined in Bayley -v- George Eliot Hospital 2017) and the ‘no treatment’ option. Naturally you would refer to the expected clinical outcome, risks, and benefits of each option.
Your role in the legal case is similar to that of the treating surgeon; you must interpret the literature and apply it to the individual’s particular case.
This is very useful – like the option 3 technique
Thanks for that Andrew – I thought it was the best way to illustrate the possible approaches.