Frantzen v Road Accident Fund (331/2021) [2022] ZASCA 107; [2022] 3 All SA 657 (SCA); 2023 (1) SA 52 (SCA) (15 July 2022)

 The appellant was involved in a motor vehicle accident in 2007 where he sustained a soft tissue injury to his neck (whiplash injury). Around 10 months later, the appellant developed a movement disorder called dystonia, which causes involuntary muscle contractions.

 The appellant sued the Road Accident Fund (the respondent) for damages related to the dystonia, arguing it was caused by the 2007 accident. The key issue was whether the dystonia was anatomically related to the site of the neck injury, which is a diagnostic criterion for post-traumatic dystonia.

 The High Court found that the anatomical relationship was not established, and therefore the causal link between the accident and dystonia was not proven. The appellant appealed to the Supreme Court of Appeal (SCA).

 The SCA examined the expert evidence, particularly whether the appellant's expert, Dr Smuts, had a logical basis for his opinion that the anatomical-link criterion was met. The SCA ultimately agreed with the High Court's finding that the anatomical-relationship criterion was not proven, and therefore the causal link was not established.

 The appeal was dismissed.

To establish factual causation between a soft tissue injury (whiplash) and a subsequent movement disorder (dystonia), the expert evidence must show a logical basis for the opinion that the onset of the movement disorder was anatomically related to the site of the original injury, as per the Jankovic criteria.

The court found that while the expert evidence (Dr. Smuts) relied on the Jankovic criteria, it did not adequately explain how the appellant's generalized dystonia, affecting multiple body parts, was anatomically related to the neck injury sustained in the accident. The court held that without this logical connection, the factual causation between the accident and the dystonia was not established on a balance of probabilities.

Expert evidence must have a logical basis that can withstand analysis, not just a genuinely held opinion (Linksfield Park Clinic).
The court is not bound to accept expert opinion just because it is genuinely held, if it is not capable of logical analysis (Linksfield Park Clinic).
There is a difference between the scientific measure of proof (certainty) and the judicial measure of proof (balance of probabilities) (Dingley v Chief Constable).

The Supreme Court of Appeal cited the following key cases in its reasoning:

 Life Healthcare Group (Pty) Ltd v Suliman 2019 (2) SA 185 (SCA) - This case dealt with the test for factual causation, which requires showing that "but for" the accident, the appellant would not have suffered the injury.

 Michael and Another v Linksfield Park Clinic (Pty) Ltd and Another 2001 (3) SA 1188 (SCA) ([2002] 1 All SA 384) - This case set out the approach to evaluating expert evidence, which requires determining whether the expert's opinions are founded on logical reasoning.

 Dingley v Chief Constable, Strathclyde Police 2000 SC (HL) 77 - This Scottish case highlighted the difference between the scientific and judicial measures of proof.

 Oppelt v Department of Health, Western Cape 2016 (1) SA 325 (CC) (2015 (12) BCLR 1471; [2015] ZACC 33) - This Constitutional Court case held that the lack of general acceptance of a scientific theory may not be the basis to reject it, without more.

 Menday v Protea Assurance Co Ltd 1976 (1) SA 565 (E) - This case established that an expert may rely on medical literature, provided the expert affirms the correctness of the statements and the publication is authored by a person of repute or experience in the field.

 S v Maqubela 2017 (2) SACR 690 (SCA) and S v Van der Walt 2020 (2) SACR 371 (CC) (2020 (11) BCLR 1337; [2020] ZACC 19) - These cases discussed the difference between the scientific and judicial measures of proof.