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Exacerbation and Acceleration - Dr Mark Burgin

06/04/22. Dr. Mark Burgin BM BCh (oxon) MRCGP describes an expert approach to the legal concepts of Exacerbation and Acceleration.

There are few subjects which are as guaranteed to cause an argument between medical experts as Exacerbation and Acceleration.

Many claimants have pre-existing problems and it is difficult to describe a worsening of symptoms without reference to these words.

In order to explain to the court it is important to know what the court considers to be Exacerbation and Acceleration.

Case law suggests that courts see the terms as meaning a serious deterioration of the underlying condition which is not how they are used in a report.

Constitutional norm

The best way of describing the claimant’s pre-existing state is the term Constitutional Norm as it suggests a dynamic rather than static state.

It is not whether the claimant was symptomatic immediately prior to the accident that matters, it is their pattern of variation.

Prognoses for a flare up 3 times a year lasting 2 weeks before the accident and an RTA increase in pain for 12 months could either be 4 months or 11 months.

The expert’s reasoning could be that the pain would have flared up anyway (at 4/12) or that 100% of the worsening was due to the accident (minus the usual flare ups).

Soft tissue injury in the area of pre-existing degenerative condition

Trying to describe the pre-existing back pain and the accident related back pain as the same injury misses the point that one is soft tissue the other is hard tissue.

Where there is no evidence to support additional hard tissue injury in the accident it is easier to separate the back pain into different problems.

The expert can then indicate that the soft tissue injury was completely due to the accident and hard tissue degenerative problems were not due to the accident.

The prognosis can then focus on the soft tissue injury and does not need to consider Exacerbation and Acceleration as this does not apply.

Asymptomatic conditions

By the age of 50 years old cervical x-rays show abnormalities in 80% and by the age of 30 years old MRI scans show disc changes in 70% of those with no symptoms.

The average age of onset of chronic neck pain is 40 years old and only 25% have a temporally associated history of trauma.

Review of medical records confirms a forgotten history of GP attendance for neck pain prior to the index accident in over half of claimants.

A better term when describing pre-existing degenerative processes in the general population is subclinical rather than asymptomatic.


With high force impacts it is reasonable to describe the injury as accelerating a previously subclinical degenerative condition through damage to hard tissues.

A previously symptomatic claimant in the same high force accident would be described as having an exacerbation (some prefer aggravation) of the degenerative condition.

Where the mechanism is unlikely to have caused damage to the hard tissues then there should be a statement that there was no acceleration or exacerbation.

As quantum in exacerbation of knee OA has been calculated at £15k the correct use of acceleration or exacerbation has major implications.

Doctor Mark Burgin, BM BCh (oxon) MRCGP is on the General Practitioner Specialist Register.

Dr. Burgin can be contacted on This email address is being protected from spambots. You need JavaScript enabled to view it. and 0845 331 3304 website

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