THE SUPREME COURT OF APPEAL OF SOUTH
AFRICA

REPORTABLE
CASE NO:   181/2004

In the matter between

DR HENK DOUW LOUWRENS                                      APPELLANT

and

JAMES PETER OLDWAGE                                        RESPONDENT

CORAM:
MPATI DP, STREICHER, MTHIYANE, LEWIS
et PONNAN JJA

HEARD:

18 MAY 2005
DELIVERED:
21 SEPTEMBER 2005

Summary: Medical negligence – Vascular surgeon diagnosed a patient as
having serious arterial disease in the right leg – diagnosis disputed – History of
symptoms with which patient presented disputed. Proper approach for resolving
factual disputes discussed.
Informed consent – whether given by patient.
Risks and post-surgical complications (steal/claudication) – whether caused by
surgical intervention.
Duty to warn patient where risks are negligible discussed. Credibility findings
by court a quo – appellate court’s approach thereto. Proper approach to expert
medical evidence discussed.
___________________________________________________________

JUDGMENT

MTHIYANE JA:
Introduction
[1] The dispute in this appeal concerns the history given by a patient
(the respondent and to whom I shall refer as the plaintiff) to a vascular
surgeon (the appellant, referred to as the defendant), in respect of the
symptoms with which he presented, leading to a diagnosis subsequently
made by the appellant. There are two conflicting versions in this regard
and the outcome of the appeal depends on which of the two versions is to
be believed, having regard to the probabilities. The plaintiff sued the
defendant in the Cape High Court for damages for alleged medical
negligence. At the commencement of the trial Yekiso J ordered a
separation of the issues in terms of rule 33(4), and subsequently dealt
only with the question of negligence. The learned judge decided that
issue in favour of the plaintiff and granted the defendant leave to appeal
to this court.

[2] These are the facts. On Monday 5 June 2000, the plaintiff was
suffering from intense pain in his right leg. He consulted his general
practitioner, Dr George Simons, who examined him and then referred
him to the defendant. The defendant saw him on Tuesday 6 June 2000
and upon examining him he suspected, as he put it, that the pain was
caused by a lack of, or poor, blood flow to the lower leg. On Wednesday

7 June, he did an angiogram on the plaintiff, which revealed that various
arteries in the right upper leg were occluded (blocked). From this he
concluded that the plaintiff had severe ischaemia, which required urgent
surgical intervention (in the form of a bypass operation). On Thursday 8
June, he performed an iliac bi-femoral bypass operation on the plaintiff.

[3] On Wednesday 14 June 2000, the plaintiff, who says that he was
still not pain free after the vascular surgery, consulted a neurosurgeon, Dr
Kieck. Dr Kieck discovered that the plaintiff had disc degeneration at the
L4/5 vertebrae which had resulted in a prolapsed disc in that area. There
is a dispute as to whether this condition had occurred before or after the
plaintiff’s visits to Dr Simons and the defendant. The back problem also
required surgery, in the form of a laminectomy. On Wednesday 21 June
2000 Dr Kieck did the back operation, which the plaintiff says brought
him instant relief. However, shortly after the back neuro-surgery, he
began to exhibit (and, according to him, continues to exhibit) symptoms
of claudication (blockage of the arteries with resultant cramping) in the
left leg. He alleges that the current claudication was caused by the
defendant’s surgical intervention.

[4] The central factual issue at the trial was whether, when the plaintiff
saw Dr Simons and the defendant, he presented with lower back pain,

which radiated from the back of his leg upwards into his buttock as a
result of a recent fall and a ‘snap’ in his back, as alleged by him, or pain
in the right lower leg (in particular the right foot), as alleged by the
defendant (supported by Dr Simons) primarily arising from his vascular
problem. The judge a quo found that the pain with which the plaintiff
presented was of neuralgic origin and not of vascular origin. In essence
thus, the judge found that the defendant had made an incorrect diagnosis.

Issues on appeal
[5] On appeal the principal issue is whether the defendant
misdiagnosed the plaintiff’s problem as being primarily of vascular rather
than of neuralgic origin which, on the plaintiff’s case, was more urgent.
Three other related issues were also raised: first, whether in examining
the plaintiff and in allegedly missing the symptoms indicative of
neuralgic/back pain, the treatment of which should have taken priority,
the defendant acted as a reasonable vascular surgeon would have done
when faced with the symptoms with which the plaintiff presented (of
course if we find that on the probabilities the defendant did not miss a
neuralgic problem this issue will fall away); secondly, whether the
plaintiff gave informed consent to the surgical procedure performed by
the defendant, in the absence of which consent such intervention would
have amounted to an assault; thirdly, whether the plaintiff’s current

claudication in the left leg was caused by the defendant’s surgical
intervention. I discuss these issues in turn.

Did the defendant make an incorrect diagnosis?
[6] The case for an incorrect diagnosis is based primarily on the
plaintiff’s evidence and on that of Professor D R De Villiers, a vascular
surgeon, who had already retired by the time of the trial. Professor De
Villiers told the court that the pain which the plaintiff described as having
experienced when he had consulted the defendant signified a
neurological rather than a vascular problem, and that he should then have
been referred to a neuro-surgeon. He did not think that the plaintiff had
critical ischaemia, which he described as a progression from intermittent
claudication - ‘a lameness, a weakness, a pain, a cramp that usually starts
in the calf muscle and may extend upwards’- not downwards - and which
comes only with exercise. According to Professor De Villiers,
intermittent claudication is not incapacitating and does not interfere with
a person’s everyday life. Claudication is only incapacitating and requires
surgical intervention when it progresses to critical ischaemia. The
symptom that signifies critical ischaemia is referred to as ‘restpain’, and
is not intermittent, but constant, extremely severe and maximal. It is
constant because it involves the nerves and is limited to the farthest part
of the foot, which is the last body part that the blood supply reaches.

Restpain indicates a fairly advanced stage of arterial disease. The worst
form of critical ischaemia manifests itself in gangrene, at which stage the
vessels become completely blocked and the tissues die. Then, nothing
can come through and the leg becomes absolutely black and dies. The
only ‘cure’ would be amputation. Although Professor De Villiers was
satisfied from what he was told that the plaintiff had not reached the
advanced stage of critical ischaemia, he conceded that, if the plaintiff
exhibited restpain at the time he consulted with Dr Simons and the
defendant, then surgical intervention was justified.

[7] I turn to the plaintiff’s evidence. He told the court that, when he
saw Dr Simons on 5 June 2000, he complained of intense pain in the
back of his right thigh, which shot up into his buttock. He also mentioned
severe pain in the back and remarked: ‘my back is buggered’.
Notwithstanding this remark, Dr Simons ‘fiddled’ with his feet, which he
considered to have nothing to do with the pain in the back.

[8] Dr Simons disputed the plaintiff’s version. He testified that the
plaintiff had mentioned pain in the lateral part of the right lower leg,
which shot up to his buttock. The plaintiff told him that he had had this
pain for some five days and made no mention of pain in the back. The
plaintiff also told him of a back operation, a laminectomy, which he had

had, way back in 1972. Thinking that the pain in the leg might be a
recurrence of the old injury, Dr Simons decided to do a straight leg-
raising test on both legs. The test achieved a 70˚ raise, as a result of
which he was satisfied that the plaintiff exhibited no neurological deficit.
In fact, in his report Dr Simons noted the absence of entrapment of the
nerve. Professor De Villiers conceded that the test carried out by Dr
Simons was indeed the normal test used to determine the presence or
absence of neurological deficit. Dr Simons also noted that the plaintiff’s
right foot was a little different to the left. He felt pulses in the left foot
but none in the right foot. He also felt pulses behind the left knee and up
in the groin but found that they were completely absent on the right side.
Having in addition established that the plaintiff was a heavy smoker,
smoking about 30 to 40 cigarettes per day, he was satisfied that the
plaintiff had definite ischaemia or lack of blood supply to the right leg.
He advised the plaintiff that there was an urgent need for correction and
that he wished to refer him urgently to a vascular surgeon, as he was
extremely concerned with what appeared to be a very greatly diminished
blood supply to the right leg. He feared that the plaintiff was in danger of
losing his leg and felt that a decision had to be made urgently.

[9] As regards the defendant’s version, he had - not surprisingly - no
independent recollection of what was said during his consultation with

the plaintiff on 6 and 7 June 2000. Since then he had seen many other
patients. He could therefore only meet the plaintiff’s version by referring
to how he routinely consulted with his patients and by referring as an
aide memoire to his records, which he had initially kept electronically on
computer, and which were replaced by a letter he sent to Dr Simons on
26 June 2000. The letter records that the plaintiff presented with a five
day history of pain in the right leg and restpain of the foot. The pain is
described as most marked over the peroneal compartment of the right
lower leg. It also records that, on examination, the right foot was clearly
ischaemic with blue discolouration and decreased temperature and that
no pulse was felt in the right leg whereas pulses were present in the left
leg. Elaborating on his report, the defendant testified that the plaintiff had
complained of pain in the right leg which he said was most pronounced
in the outer part of the lower leg, just above the ankle. He noticed that the
plaintiff limped into the examination room and that his foot had a dusky,
light bluish colour and was cool to the touch. It was clear to him that the
plaintiff had severe pain seeing that, as he walked, he attempted to place
as little weight as possible on the right foot.

[10] The defendant suggested that an angiogram be done to define the
severity and extent of the disease, on the basis of which he could then
recommend corrective treatment. The angiogram revealed a much more

severe situation than the defendant had anticipated. Not only were the
main vessels which supplied blood to the right leg blocked, but the other
vessels which normally provide alternate routes were also blocked. The
external right iliac artery - the vessel that normally takes the blood down
the leg - was completely blocked off. Although there were also blockages
on the left hand side, the plaintiff’s body had compensated adequately for
that deficit. There was sufficient blood getting to the left foot via
collateral arteries, which acted as effective substitutes for the arteries that
were disabled by the blockage. The angiogram confirmed the defendant’s
earlier clinical suspicion of a very poor blood flow to the right leg. In the
light of this he diagnosed the plaintiff as having severe ischaemia. He
considered that the leg was under threat and that the next stage, if the
vascular problem was left uncorrected, would be the setting in of
gangrene, with the consequent risk of amputation of the lower leg. The
defendant testified that if a leg did not receive blood it was starved of
nutrients which are essential for it to function. In the absence of nutrients,
the leg would be jeopardised, which was the prospect facing the plaintiff.
The defendant considered that, if there were a minor injury to the leg,
infection could set in and speed up this process. He was of the view that
the plaintiff faced the real prospect of losing his leg and that something
had to be done urgently.

[11] The defendant stated that he attempted to explain the situation to
the plaintiff in as understandable a manner as possible. He advised the
plaintiff that his vascular problem could be corrected by doing an aorta-
bi-femoral bypass, which entailed bypassing both iliac systems (affected
by blockages) and re-routing the blood along substitute tubing to the
lower part of the leg which was not getting adequate supply of blood.
This suggested surgical procedure turned out to be beyond the plaintiff’s
financial means, however, as the hospital and clinic fees alone amounted
to between R80 000 and R90 000. Notwithstanding that the defendant
was prepared to lower his fees, the aorta bi-femoral bypass surgical
procedure was excluded as a viable financial option, as the hospital and
the clinic were not prepared to lower their charges.

[12] The defendant then suggested a cheaper, simpler and less risky
surgical procedure, an iliac bi-femoral bypass, the cost of which was in
the region of R40 000. The plaintiff agreed to this procedure and the
operation was done on 8 June 2000.

[13] In deciding which of the two opposing versions is to be accepted, it
is necessary to have regard first to what transpired at the consultation the
plaintiff had with Dr Simons and later with the defendant, in respect of
the history given to them by the plaintiff and their clinical findings,

assessed in the light of the probabilities. The plaintiff’s version as to the
pain with which he presented and which he described to Dr Simons and,
later, to the defendant (namely the complaint concerning back pain) is
totally divergent from and incompatible with the defendant’s version of
ischaemic vascular disease of the right lower leg and foot, with which he
says the plaintiff presented and described to him. All the plaintiff’s
experts were agreed that if, at the time, the plaintiff had back pain only
and no pain in the lower leg and foot, the plaintiff’s problem was of
neuralgic origin.

[14] It seems to me that the issue for determination is whether the
plaintiff, when he consulted the defendant, suffered from a neuralgic or a
vascular problem, and this is entirely dependent upon which factual
version is to be accepted. If there was a dual pathology, then we must
determine whether the procedure followed by the defendant was correct.
The dispute thus involves a choice between the version of the plaintiff,
on the one hand, and that of the defendant on the other, supported by Dr
Simons. Yekiso J accepted the plaintiff’s version in preference to that of
Dr Simons and the defendant. Counsel for the plaintiff urged us to follow
suit and submitted, somewhat boldly it must be said, that the judgment of
the court a quo includes findings of credibility with which the appellate
court will not normally interfere. We were not referred to any specific

passage in the judgment recording such credibility findings. I could not
find any. Indeed, it is not apparent from the record why the version of Dr
Simons and the defendant was rejected. On a proper approach, the choice
or preference of one version over the other ought to be preceded by an
evaluation and assessment of the credibility of the relevant witnesses,
their reliability and the probabilities. (See Stellenbosch Farmers’ Winery
Group Ltd & another v Martell Et Cie & others1). Unfortunately it is not
apparent from the record that this approach was adopted by the judge a
quo. I do not think this is a case where, sitting as a court of appeal, we
should defer to the trial court’s findings of credibility because of the
peculiar advantages it had of seeing and hearing the witnesses. Even if
such findings were in fact made by the trial court, I do not think that we
are precluded from dealing with findings of fact which do not in essence
depend on personal impressions made by a witness in giving evidence,
but are rather based predominantly upon inferences from the facts and
upon the probabilities. In Union Spinning Mills (Pty) Ltd v Paltex Dye
House (Pty) Ltd & another2 this court, per Zulman JA, said:
‘Although Courts of appeal are slow to disturb findings of credibility they generally
have greater liberty to do so where a finding of fact does not essentially depend on the
personal impression made by a witness’s demeanour but predominantly upon
inferences from other facts and upon probabilities. In such a case a Court of appeal

1 2003 (1) SA 11 (SCA).
2 2002 (4) SA 408 (SCA) para 24. See also R v Dhlumayo & another 1948 (2) 677 (A) at 698 and S v
Robinson & others 1968 (1) SA 666 (A) at 675G-H.

with the benefit of an overall conspectus of the full record may often be in a better
position to draw inferences, particularly in regard to secondary facts.’

[15] It follows therefore that the factual evidence presented to the court
a quo merits reconsideration and re-evaluation. It seems to me that, if the
plaintiff’s version regarding the history he gave to Dr Simons and the
defendant is to be believed, the two doctors not only clinically missed his
back problem, but deliberately chose to ignore it, notwithstanding that he
had specifically mentioned it to them. This is in my view highly
improbable. Furthermore, it is difficult to see why the two doctors,
consulting the plaintiff individually and separately on different dates,
would both focus on the right leg, in respect of which there was (on the
plaintiff’s version) no complaint. There is yet another important feature.
Is it merely a coincidence that the leg depicted on the angiogram
happened to be the leg that was in fact occluded? The picture revealed in
the angiogram appears to support the diagnosis, made by both Dr Simons
and the defendant, of a severe vascular problem in the right leg and
contradicts the plaintiff’s assertion that he had no pain in the right foot or
that there was nothing wrong with his right lower leg. The evidence that
the plaintiff, when he saw Dr Simons and the defendant, complained of
pain in the right lower leg (in particular the right foot) and not of pain in
the back, and the defendant’s clinical findings in this regard are

supported by all objectively verifiable facts and circumstances. Those
include the earlier presentation to Dr Simons who, in broad terms, made
similar findings to those of the defendant; the angiogram which depicted
a vascular condition with very little blood flow  to the right lower leg; the
defendant’s letter to Dr Simons dictated some 3 weeks after the operation
and from contemporaneous notes clearly confirming the defendant’s
version of events; and the clinical note made by Dr Kieck that the
plaintiff had told him about pain in his right calf prior to his visit to the
defendant.

[16] As indicated above, Professor De Villiers conceded that if, at the
time, the plaintiff exhibited restpain, surgical intervention was justified.
In this regard the court had only the evidence of the plaintiff to be
weighed against that of the defendant. The defendant noted restpain in
the letter he sent to Dr Simons. Dr Simons did not specifically mention
the presence of restpain, a fact which might to some extent be taken to
support the contention that vascular surgical intervention was not urgent.
Dr Simons did, however, testify that on examination he found the
plaintiff’s right foot to be ‘a little different to the left’; he felt no pulses in
the right foot, which to him suggested severe arterial disease. Dr Kieck
did not note restpain but made a note that the plaintiff had told him about
pain in his right calf prior to his visit to the defendant. The bits and pieces

of evidence that support the contention that there was no restpain at the
time of the visits to Dr Simons and to the defendant pale into
insignificance when one has regard to the evidence of the two doctors
and the other supporting evidence. I think it is fair to accept that a general
practitioner such as Dr Simons would not have wished or been able to do
a more in-depth investigation than a specialist. That is why he referred
the plaintiff to the defendant for further evaluation. His failure expressly
to mention restpain in his notes does not mean that he missed it.

[17] The evidence of the plaintiff is riddled with other difficulties. It is
contradicted by the angiogram which demonstrated that he had a serious
vascular problem notwithstanding his protestation that there was nothing
wrong with his right lower leg. The plaintiff was also contradicted by his
estranged wife, Ms Marlene Oldwage, who told the court during cross-
examination that, when the defendant visited Dr Simons, the pain in his
back resulting from a fall in the Cederberg had long disappeared. She
said at that stage he complained of pain in the leg. There are also
discrepancies between, on the one hand, the plaintiff’s evidence relating
to exercise, and that of his wife and his brother, Mr George Henry
Oldwage, on the other. The evidence of the plaintiff’s wife and of his
brother in this regard also does not tie up in several respects. The plaintiff
testified that, before the vascular operation, he used to do a lot of exercise

in the form of walking, swimming and cycling. The plaintiff’s evidence
was that he and his wife used to cycle after supper but his wife said they
cycled before supper. Her evidence was that they used bikes belonging to
the plaintiff, whereas his brother said that the bikes which the plaintiff
and his wife used belonged to him. The plaintiff’s brother said that he
had bought a bike for his girlfriend and two for his children, and that the
latter were the bikes that he lent to the plaintiff and his wife. At some
stage the contradictions become comical: the plaintiff’s wife said under
oath that she and the plaintiff had brought two bikes with them to the
Cederberg and said: ‘O, ons het `n Mercedes gehad, en agter die
Mercedes was die ding waar ons die fietse gesit het’. To a further
question in cross-examination, she replied that the plaintiff cycled on his
own bike. At first glance these contradictions seem to be minor. But
when the plaintiff’s account of his exercising regime is contrasted with
the expert medical evidence of Professor Immelman, Dr Stein and the
defendant, all supported by the angiogram, to the effect that the state of
the plaintiff’s arterial disease was such that he could not do exercise to
the extent to which he claims he did, the contradictions assume
importance. Those small lies cumulatively make one question the truth of
the plaintiff’s evidence. In particular, the claim by the plaintiff’s brother
that the plaintiff cycled some 50 kilometres up the mountain pass is
totally discredited by the medical evidence. It seems to me that the

evidence of the plaintiff and his witnesses to the effect that he engaged in
such exercise before the defendant’s surgical intervention must be
rejected as contrived and unworthy of credence.

[18] I also do not agree that the symptoms with which the plaintiff
presented were neurological and related to his back, rather than vascular.
First, the plaintiff did not inform Dr Simons and the defendant that he
had slipped and injured his back in the Cederberg. I find the evidence of
the doctors more reliable and persuasive than that of the plaintiff. It
cannot be said that the defendant lied to the court in the version which he
presented. Against this is the evidence of the plaintiff which is very
unreliable. Furthermore, the probabilities militate against the contention
that Dr Simons and the defendant missed and/or ignored the back pain
which the plaintiff says he mentioned to them.

[19] There is yet another feature that supports the version of Dr Simons
and the defendant and contradicts that of the plaintiff. The plaintiff says
he was not pain-free after the surgical procedure performed by the
defendant. In this regard he is contradicted by the hospital notes prepared
by the nurses during his post-operation confinement, from which it
appears that he did not complain of any pain. His explanation when
confronted with this in cross-examination, to the effect that he did not

complain because he wanted to be discharged, is not at all convincing.
Also, the plaintiff said that when Dr Simons visited him at home after the
vascular operation, he told the doctor that he was suffering from exactly
the same pain that he had before the operation. This was disputed by Dr
Simons who said that the plaintiff mentioned pain in the back. Indeed,
when he went to see Dr Kieck, the neurologist, he was diagnosed as
having a back problem for which he underwent surgery on 21 June 2000,
after he had told Dr Kieck of the incident in which he hurt his back and
of the back pain that shot down to the right leg. In my view, this supports
the version of Dr Simons, that when he visited the plaintiff at home, the
latter complained of pain in the back and casts serious doubt on the
plaintiff’s version in this regard. Furthermore, at the first consultation, as
I have already indicated, Dr Simons did a leg raise, achieving a 70˚
elevation of both legs, from which he concluded that there was no nerve
entrapment. Dr Kieck was only able to achieve a leg raise of 30˚ in the
right leg. It is therefore clear that the symptoms with which the plaintiff
presented to Dr Simons and to the defendant were different to those with
which he presented to Dr Kieck. In my view, there is no basis for
concluding that the pain which the plaintiff had when he went to see Dr
Simons and the defendant arose from a neurological problem.
Accordingly, on all the evidence, the defendant’s surgical intervention

was justified and there is no basis for a finding of misdiagnosis. In
Mitchell v Dixon3 Innes ACJ said:
‘A practitioner can only be held liable in this respect, if his diagnosis is so palpably
wrong as to prove negligence, that is to say, if his mistake is of such a nature as to
imply absence of reasonable skill and care on his part, regard being had to the
ordinary level of skill in the profession.’
In the present matter it cannot be said that the defendant was negligent or
did not exercise the necessary care and skill required of him in making
the diagnosis. I am saying this mindful of the fact that the defendant was
a specialist and that what is expected of him is the following:
‘A specialist is required to employ a higher degree of care and skill concerning
matters within the field of his speciality than a general practitioner. The objective
“reasonable physician test” is subjectified to the particular branch of medicine to
which the specialist belongs. This means that it is expected from a specialist in the
treatment of his patients to act as a reasonable specialist would have done under
similar circumstances.’4
On all the evidence that is exactly what the defendant did. He examined
the plaintiff’s problem in depth, subjected him to an angiogram and did
what he and other specialists, Professor Immelman and Dr Stein,
considered to be an appropriate operation to treat the plaintiff’s
condition. In my view there is no basis for a finding of incorrect
diagnosis.

3 1914 AD 519 at 526.
4 N J B Claasen & T Verschoor Medical Negligence in South Africa (1992) p 15.

Did the defendant perform an incorrect surgical procedure?
[20] Allied to the above question is the issue whether the defendant
acted as a reasonable vascular surgeon would have done when faced with
the symptoms with which the plaintiff presented, referred to in para 5
above. According to the plaintiff’s expert witness, Professor De Villiers,
the defendant should have done an aorta bi-femoral bypass. The problem
was that the plaintiff could not afford that procedure and, for that reason,
the defendant suggested the iliac bi-femoral bypass, a simpler, cheaper
and less risky - but by no means inferior - surgical procedure. As regards
the plaintiff’s lack of sufficient funds, Professor De Villiers suggested
that the procedure could have been done at a public hospital. There was
however overwhelming evidence from Professor Immelman that this was
not possible. He testified that the plaintiff might not have met the means
test. Besides, there was a long waiting list and the plaintiff would not
have been permitted to jump the queue. If the defendant’s evidence of the
plaintiff’s serious arterial disease is anything to go by, his leg might well
have had to be amputated by the time his turn came. It seems to me that
on the acceptable evidence the defendant acted reasonably in his
treatment of the plaintiff. In any event the plaintiff would have been
aware of the existence of public hospitals but chose to consult a private
practitioner who could perform an operation which was appropriate and
which cured the deficient blood supply to the plaintiff’s lower right leg.

In the circumstances even if the plaintiff could have had the more
expensive operation done at a public hospital there was no duty on the
defendant to refer him to such a hospital. What is reasonable in the
circumstances was explained by Innes CJ in Van Wyk v Lewis5 where he
said:
‘…[in] deciding what is reasonable the Court will have regard to the general level of
skill and diligence possessed and exercised at the time by the members of  the branch
of the profession to which the practitioner belongs.’
On the acceptable evidence there can be no question that the methods
used by the defendant to diagnose the plaintiff’s problem were those used
in his profession and the surgical procedure he performed was the correct
one. The plaintiff could not dispute this but was driven to contend,
relying on the evidence of Professor De Villiers, that there had been a
dual pathology and that treatment of the vascular problem diagnosed by
the defendant was not urgent. On the evidence of Dr Simons and the
defendant the dual pathology had not been presented to them. According
to them the plaintiff exhibited a serious vascular disease and the
angiogram confirmed this. No mention was made of pain in the back. I
accept their evidence. The views and the conclusion reached by Professor
De Villiers suggesting the presence of dual pathology, at the time the
plaintiff was seen by Dr Simons and the defendant, must therefore be

5 1924 AD 438 at 444.

rejected. It is true that in his letter to Dr Simons dated 26 June 2000 the
defendant does allude to the possibility of dual pathology but in my view
that seems to be based on the fact that subsequently the plaintiff was
found by Dr Kieck to have a neurological problem. It is by no means an
admission that at the time he was seen by himself and Dr Simons the
plaintiff had both a vascular problem and a neurological problem.

Was there informed consent?
[21] In argument it was submitted that the plaintiff did not consent to
the surgical procedure performed by the defendant (the iliac bi-femoral
bypass). Counsel argued that the plaintiff did not know what procedure
was performed. He drew attention to the consent form signed by the
plaintiff in which the operation was described as a ‘fem-fem bypass’
whereas an iliac bi-femoral bypass was performed. There is no merit in
the argument. According to the defendant that is the general terminology
used for the cross-over bypass whether it be an iliac bi-femoral or a
femoro-femoral bypass. Professor De Villiers testified that the difference
was of semantic interest only and that although the medical literature
referred to the femoro-femoral bypass everybody did the iliac-femoral
bypass. The defendant explained in detail to the plaintiff the surgical
procedure he planned to do and which was eventually done. In the
circumstances I am satisfied that the plaintiff gave informed consent to

the operation. In any event Professor De Villiers conceded that the iliac
bi-femoral bypass or the cross-over bypass was superior to the femoro-
femoral bypass, because of its advantages in facilitating a natural flow of
blood to the extremities.

Was the plaintiff warned of the risks involved and was his current
claudication caused by the defendant’s surgical intervention?
[22] It was argued that the defendant had failed to warn the plaintiff of
the risks at stake. In Castell v De Greef6 Ackermann J said:
‘For consent to operate as a defence the following requirements must, inter alia, be
satisfied:
(a)
the consenting party “must have had knowledge and been aware of the
nature and extent of the harm or risk”;
(b)
the consenting party “must have appreciated and understood the nature
and extent of the harm or risk”;
(c)
the consenting party “must have consented to the harm or assumed the
risk”;
(d)
the consent “must be comprehensive, that is extend to the entire
transaction, inclusive of all its consequences”.’
Relying on Castell v De Greef it was argued that the defendant should
have explained the likelihood of claudication occurring as a result of the
iliac bi-femoral bypass, the so-called ‘small operation’. Professor De

6 1994 (4) SA 408 (C) at 425H-I.

Villiers said that the claudication which the plaintiff experienced on the
left leg is undoubtedly due to what is termed a ‘steal syndrome’, as
evidenced by the fact that the first time the plaintiff walked after his back
operation, he had claudication of the left leg. He said that the problem in
the left leg relates directly to the vascular operation. For this view
Professor De Villiers relied on what he called Veteran Administration
Studies (VA studies). The results of the study were published in 1976. It
was then the largest study in the world of patients who had undergone
these extra-anatomical bypasses. The study was conducted on ex-war
veterans from the Second World War and the wars in Korea and Vietnam
at the Veteran Administration Hospitals which were built across
America. Professor De Villiers said four per cent of these patients
demonstrated clinical manifestations of ‘steal’ and that the defendant
should have anticipated a four per cent possibility of ‘steal’. In simple lay
terms what Professor De Villiers suggested was happening was that
blood which was meant to flow down the left leg was now being diverted
to the right leg. He argued that the claudication was directly related to the
smaller operation, that is the iliac bi-femoral bypass. He said that if a
bigger operation, that is the aorta bi-femoral bypass had been done, the
graft would have been taken down to the knee level on the left and the
plaintiff would not be having a problem. Of course the evidence was that

the latter operation could not have been done because the plaintiff could
not afford it.

[23] Professor Immelman who gave evidence on behalf of the plaintiff
said that there was only a two per cent chance of steal occurring where
the smaller operation (the iliac bi-femoral bypass) was done. He said that
the comparison made by Professor De Villiers and the conclusion
reached by him were simply not valid. To compare the situation as it was
in the year 2000 with a study that was done in 1976 at a hospital which
simply did not have many of the tests available to a vascular surgeon
today was unrealistic. So, for example, in the cases referred to in the
study, angiograms were not performed to ascertain if there was stenosis
(narrowing of the vessels), whereas the defendant had done the
angiogram in the present matter. Professor Immelman also pointed out
that the war veteran hospitals where these studies were done were not
well-equipped. He said the VA studies are not highly regarded as
scientific studies.

[24] Professor Immelman further pointed out that what makes modern
vascular procedure difficult to compare with the VA studies is that the
veterans were a generally unhealthy lot. They smoke; they drink; they are
obese and they tend to have very extensive diseases. He had seen them

when he visited some of these hospitals when he was in the United
States. He did not consider it fair to compare that group of patients with
an average patient in South Africa in the year 2000. He pointed out that,
since that study in 1976, technology and investigations have improved
enormously and the ‘steal’ percentage in cross-over by-passes, if it was
four per cent in 1976, must now surely be a lot lower than that. As
indicated he put the risk of ‘steal’ as being no higher than two per cent.

[25] The reasons advanced by Professor Immelman appear to me to be
so compelling that I have no hesitation in accepting them. If there was
only a two per cent chance of ‘steal’ occurring then the risk to the
plaintiff was so negligible that it was not unreasonable for the defendant
not to mention it. In Richter and another v Estate Hammann7 a neuro-
surgeon was found not to have been negligent in failing to warn the
patient where on the evidence there was only a remote possibility of
complications arising. The court said that the doctor’s actions had to be
tested by the standard of the reasonable doctor faced with the particular
problem. In this regard Watermeyer J said the following:
‘A doctor whose advice is sought about an operation to which certain dangers are
attached – and there are dangers attached to most operations – is in a dilemma. If he
fails to disclose the risks he may render himself liable to an action for assault,

7 1976 (3) SA 226 (C) at 232G-H.

whereas if he discloses them he might well frighten the patient into not having the
operation when the doctor knows full well that it would be in the patient’s interest to
have it. It may well be that in certain circumstances a doctor is negligent if he fails to
warn a patient, and, if that is so, it seems to me in principle that his conduct should be
tested by the standard of the reasonable doctor faced with the particular problem. In
reaching a conclusion a Court should be guided by medical opinion as to what a
reasonable doctor, having regard to all the circumstances of the particular case,
should or should not do. The Court must, of course, make up its own mind, but it will
be assisted in doing so by medical evidence.’
In my view of the evidence, the likelihood of steal occurring, with the
resultant claudication, was so negligible that no duty arose on the
defendant to mention it and his omission to do so did not constitute
negligence. In any event there is no evidence that the plaintiff’s current
claudication is due to ‘steal’ or that, if it is the result of ‘steal’, it is due to
the cross over bypass performed on the plaintiff. The evidence was that
there are many causes of ‘steal’. Poor heart functioning is one of them.
Professor Immelman said that if ‘steal’ does occur, it can be rectified by a
minor operation. For the above reasons it was not in my view shown that
there was an absence of informed consent or that the claudication was
due to the defendant’s surgical intervention.

Expert evidence and how it was dealt with at the trial.

[26] It is perhaps appropriate at this stage to touch on how the expert
evidence was dealt with by the judge a quo in coming to his conclusion.
Each side called experts eminently qualified in their respective fields.
Professor De Villiers, a retired vascular surgeon, Dr Harries-Jones, a
consultant radiologist and Dr Parker, a neurosurgeon, gave evidence for
the plaintiff. Dr Stein, a vascular surgeon, Professor Immelman, a
vascular surgeon and the Head of the Vascular Unit at Groote Schuur
Hospital, testified on behalf of the defendant. Their evidence was helpful
and illuminated many obscure and complicated aspects and contributed
enormously to the understanding of the issues for decision in this case.

[27] Confronted with the battery of experts on either side, presenting
competing and contrasting evidence, the learned judge preferred the
evidence of the plaintiff’s experts to that of the defendant without
advancing any basis for so doing. All that he said was that the opinions of
Professor De Villiers and Dr Parker are based on logical reasoning but he
failed to give any demonstration of this. The learned judge did not give
equal credit to Drs de Kock and Stein and Professor Immelman whose
views he harshly dismissed as being incapable of logical analysis and
support. I do not share these views. The conclusion reached was clearly

wrong. It is an approach which this court has recently decried in Michael
and another v Linksfield Park Clinic (Pty) Ltd,8 where it was said:
‘…it would be wrong to decide a case by simple preference where there are
conflicting views on either side, both capable of logical support. Only where expert
opinion cannot be logically supported at all will it fail to provide “the benchmark by
reference to which the defendant’s conduct falls to be assessed”.’
The uncritical acceptance of the evidence of Professor De Villiers and the
plaintiff’s other expert evidence and the rejection of the evidence of the
defendant’s expert witnesses falls short of the requisite standard and the
approach laid down by this court in Michael v Linksfield Park Clinic.
What was required of the trial judge was to determine to what extent the
opinions advanced by the experts were founded on logical reasoning and
how the competing sets of evidence stood in relation to one another,
viewed in the light of the probabilities. I have already indicated why I
found the evidence adduced on behalf of the defendant to be more
acceptable than that of the plaintiff’s witnesses and why the conclusion
of the trial court cannot stand.

[28] In the result the following order is made:
1.
The appeal is upheld with costs, including the costs consequent
upon the employment of two counsel.

8 2001 (3) SA 1188 (SCA) para 39.

2.
The order of the court a quo is set aside and replaced with the
following:

‘The plaintiff’s action is dismissed with costs, including the costs
consequent upon the employment of two counsel.’

__________________

KK MTHIYANE
JUDGE OF APPEAL

CONCUR:

MPATI DP
STREICHER JA
LEWIS JA
PONNAN JA