Continuing from part 1, with this part 2, of my response to a Jeffrey Liss' question in a comment under my post, "The Shroud of Turin: 3.6. The man on the Shroud was crucified":
"One question for you, though. I am curious why you prefer Barbet's research to that of Zugibe. My recollection is that they reach different conclusions as to placement of the nails and cause of death."
Liss did not specifically ask about the different conclusions Barbet and Zugibe reached over whether: 1) the hand's median nerve would be damaged by a Roman crucifixion nail through Destot's space; and 2) whether that would then cause the thumb to fold under, and thus explain why there are no thumbs visible on the Shroud.
[Above: Grey's Anatomy diagram 817 of the human right hand, palm facing, showing median nerve (yellow left) overlaid by the estimated pathway of a 1/3rd inch = 8.5mm square Roman nail from its entry point at Destot's space to its exit point about 1 cm back towards the wrist (see below)]:"Deep Palmar Nerves": Wikipedia. As can be seen, a nail of that square shape could cause damage the median nerve (both directly and by displacing carpal bones against the nerve) at a point which controls the thumb muscles.]
Nevertheless this was a major point of disagreement (again not personally because Barbet died in 1961) between Dr Pierre Barbet (1884–1961), Chief Surgeon at Saint Joseph's Hospital, Paris and Dr Frederick T. Zugibe (1928-2013), Chief Medical Examiner of Rockland County, New York.
The thumbs are not visible on the Shroud because of damage to each hand's median nerve (Barbet). Barbet reported on the results of experiments he performed during 1932-35 on freshly amputated hands, as Chief Surgeon of St Joseph's Hospital in Paris:
"But these experiments had yet another surprise in store for me. I have stressed the point that I was operating on hands which still had life in them immediately after the amputation of the arm. Now, I observed on the first occasion, and regularly from then onwards, that at the moment when the nail went through the soft anterior parts, the palm being upwards, the thumb would bend sharply and would be exactly facing the palm by the contraction of the thenar muscles, while the four fingers bent very slightly; this was probably caused by the reflex mechanical stimulation of the long flexor tendons. Now, dissections have revealed to me that the trunk of the median nerve is always seriously injured by the nail; it is divided into sections, being broken sometimes halfway and sometimes two-thirds of the way across, according to the case. And the motor nerves of the oponens muscles and of the short  flexor muscle of the thumb branches at this level off the median nerve. The contraction of these thenar muscles, which were still living like their motor nerve, could be easily explained by the mechanical stimulation of the median nerve. Christ must then have agonised and died and have become fixed in the cadaverous rigidity, with the thumbs bent inwards into His palms. And that is why, on the shroud, the two hands when seen from behind only show four fingers, and why the two thumbs are hidden in the palms." (Barbet, P., 1953, "A Doctor at Calvary," pp.118-119. Emphasis original).
In his Doctor at Calvary Barbet shows two xrays of a large (1/3 inch = 8.5 mm square) Roman nail which entered a cadaver's hand at Destot's space and exited about a centimetre back towards the wrist:
[Above: Side view of xray of a 1/3rd inch = 8.5 mm square Roman nail of which entered a cadaver's hand at Destot's space and exited at the back of the hand, about a centimetre towards the wrist: Barbet, 1953, "Doctor at Calvary," p.104B).]
[Above: Top view (flipped vertically) of the same Roman nail above. The rectangular shape is because the nail is oblique to the xray. Note the displaced Capitate carpal bone riding over the Scaphoid and Trapezoid carpal bones. The underlying median nerve would likely be pinched against these displaced carpal bones and damaged as the large, 8.5 mm square Roman nail moved upward through Destot's space to exit slightly backward towards the wrist.]
The late Dr. Robert Bucklin, Medical Examiner, Los Angeles, agreed with Barbet's conclusion:
"The fact that on the imprint of the hands no thumb is visible is explained by the fact that the nail passing through the bones of the wrist either penetrated or stimulated the median nerve. The motor function of the median nerve is flexion of the thumb, and the flexed thumb over the palm remained in that position after rigor mortis was established and for that reason does not appear on the hand imprint. Some suggestion of the pain suffered by a suspended victim with a nail through or near his median nerve is possible when one realizes that the median nerve is a sensory as well as a motor nerve." (Bucklin, R., 1970, "The Legal and Medical Aspects of the Trial and Death of Christ," Medicine, Science and the Law, January).
But Zugibe simply dismissed Barbet's experimental findings as "not anatomically possible":
"Barbet made another serious error, claiming that when he drove the nail through Destot's Space, anywhere from 1/2 to 2/3 of the trunk of the median nerve was severed. This is not anatomically possible, because the median nerve is not located in the area of Destot's Space but instead runs along the wrist on the thumb side and along the thenar furrow into the palm of the hand. An easy way to locate the median nerve on your own wrist is to bend your wrist forward. You will see a firm, ropelike structure jutting outward. This is the palmaris longus tendon. The median nerve runs along the thumb side of this tendon, not the little-finger side. Obviously, Barbet was damaging the ulnar nerve, which runs in the area of Destot's Space." (Zugibe, F.T., "The Crucifixion of Jesus: A Forensic Inquiry," 2005, p.74).
It is ironic that Zugibe, in his books and at least one article, prides himself as being more scientific than other Shroud researchers, e.g.:
"Many medical articles have been written but are entirely speculative and devoid of experimental studies. Many scientists frequently forget that it is their duty, whenever possible, to provide experimental support for their hypotheses." (Zugibe, F.T., 1995, "Pierre Barbet Revisited," Sindon N.S., Quad. No. 8, December)yet it is Barbet who did the experiments and reported his results. Moreover, Zugibe did not try to repeat Barbet's experiments but simply dismissed (wrongly) Barbet's experimental findings as "not anatomically possible"!
Apart from effectively calling Chief Surgeon Barbet a liar, and both Barbet and Medical Examiner Bucklin effectively incompetent, Zugibe again is demonstrably wrong! As can be seen above, a large square Roman nail, of side 1/3rd of an inch (8.5 mm) which Barbet used in his experiments:
"If one examines a frontal cutting of the wrist, and better still a radiograph taken from in front, one finds that in the middle of the bones of the wrists there is a free space, bounded by the capitate, the semi-lunar, the triquetral and the hamate bones. We know this space so well that we know, in accordance with Destot's work ... this space is situated just behind the upper edge of the transverse carpal ligament and below the bending fold of the wrist. I did not appreciate the importance of all this till I had made the following experiment: having amputated an arm two-thirds of the way up, I took, immediately after the operation, a square nail with sides of 1/3 of an inch (like those of the Passion), the length of which I had reduced to 2 inches for convenience of radiography. The hand was laid flat with its back on a plank, and I placed the point of the nail in the middle of the bending fold of the wrist, the nail being vertical. Then, with a large hammer, I hit the nail, as an executioner would do who knew how to hit hard. I repeated the same experiment with several men's hands (the first had belonged to a woman). Each time I observed exactly the same thing. Once it had passed through the soft parts, and the nail had entered fully into the wrist, I could feel it, in spite of my left hand which was holding it firmly, moving a little obliquely, so that the base was leaning towards the fingers, the point towards the elbow; it then emerged through the skin of the back of the wrist at about a centimetre above the point of entry, which I observed after removing the nail from the plank. (Barbet, 1953, pp.115-116)could damage the median nerve, both directly and indirectly by displacing carpal bones against it.
Zugibe has two further arguments, both of them straw man fallacious (if not dishonest) against Barbet's "missing thumbs" hypothesis:
"The Missing Thumbs For decades, one of the major points used by the defenders of the Shroud's authenticity was the absence, of the thumbs. The expression `Could a forger have imagined this?' was coined by Barbet when he postulated that the missing thumb on the Shroud was due to injury to the median nerve by the passage of the nail, which stimulated the nerve, causing the thumb to be drawn in to the palm of the hand. This phrase has been quoted innumerable times in books, magazine articles, lectures, etc. It has become a `Shroud spin.' Barbet's explanation, however, is incorrect, and there is a simple explanation that separates fact from fiction. The reason the thumbs are not visible on the Shroud image is because their natural position both in death and in the living person is in the front of and slightly to the side of the index finger. This is readily demonstrated by extending your arms in front of you with your hands in a relaxed position. Note that the thumbs are below and behind the index finger. Cross your wrists and note that your thumbs are hidden behind the index fingers. I have observed this on a daily basis in the medical examiner's office for over 34 years on deceased individuals who are regularly brought into our morgue wrapped in shrouds or sheets with their wrists crossed and frequently tied together. The shrouds or sheets that cover the bodies never contact the thumbs. In every case, the thumbs are in a position in front of and slightly to the side of the index fingers." (Zugibe, 2005, p.80).The strawman fallacy of Zugibe's argument above is that Barbet was not referring to the normal relaxed state of the thumb. The recently dead hands that Barbet performed his experiments on would already have assumed the normal relaxed state that Zugibe is referring to. What Barbet described (see above) is a further state of contraction of the thumb:
"I was operating on hands which still had life in them immediately after the amputation of the arm. Now, I observed on the first occasion, and regularly from then onwards, that at the moment when the nail went through the soft anterior parts, the palm being upwards, the thumb would bend sharply and would be exactly facing the palm by the contraction of the thenar muscles." (Barbet, 1953, p.118. My emphasis).
It is unscientific (if not dishonest) for Zugibe to not properly state Barbet's description and then attempt to refute that. That Zugibe does not do so is itself evidence that he cannot refute Barbet's "missing thumbs" hypothesis and needs to resort to setting up a strawman of Barbet's position and then `refute' that:
"A straw man, also known in the UK as an Aunt Sally, is a common type of argument and is an informal fallacy based on misrepresentation of an opponent's position. To "attack a straw man" is to create the illusion of having refuted a proposition by replacing it with a superficially similar yet unequivalent proposition (the "straw man"), and to refute it, without ever having actually refuted the original position." ("Straw man," Wikipedia, 2 December 2013).
Moreover, Zugibe's claim that "the thumbs ... natural position ... in death" is "below and behind the index finger" cannot be a general rule. A Google search on "Egyptian mummy hand" revealed that many (if not most) Egyptian mummies had their hands arranged flat across their bodies with their thumbs visible, e.g. the mummy of Egyptian pharaoh Ramses I, whose hands are crossed flat on his body with both his thumbs clearly visible (see below).
[Above: The 3,000-year-old Egyptian mummy believed to be that of King Ramses I: Ancient Egypt. Note that his hands are crossed flat over his body and his thumbs are clearly visible, not "in the front of and slightly to the side of the index finger" which Zugibe claimed was "their natural position both in death and in the living person."]
[Above: The man of the Shroud's hands crossed in front of him, with his right hand against his body (left because of mirror reversal)and his left hand against his right wrist, and (unlike most Egyptian mummies, e.g. Ramses I), his thumbs are not visible, consistent with Barbet's hypothesis that crucifixion nails hammered in through Destot's space damaged the hands' median nerves, causing the thumbs to flex tightly against the palms: Scope: Durante 2002 Vertical.]
most natural way to arrange his hands would have been for his hands to be flat, with his right thumb against his body and his left thumb against his right arm, unless his thumbs were so bent back hard against his palms, as the thumbs in Barbet's experiments were, and then fixed by rigor mortis so that they could not be easily straightened out.
Zugibe's second argument against Barbet's "missing thumbs" hypothesis, is also fallacious (and seemingly dishonest):
"Therefore, Barbet's explanation is incorrect for two reasons: 1) the median nerve does not pass through Destot's Space, and 2) even if it did and was injured, there would be no flexion of the thumb. Dr. Lampe relates that in severance of the median nerve, `there is inability to flex the thumb, index and middle fingers.' This was confirmed in the case of the women described above who was stabbed in the Z-area of the hand while defending herself. Although the median nerve was injured and the knife exited in the exact place where the Shroud shows the hand wound image, the thumb was not drawn in to the palm.' (Zugibe, 2005, p.80).
First, Barbet never said that the median nerve passed through Destot's space, nor does his "missing thumbs" hypothesis require it. As can be seen above, what Barbet said was, that "at the moment when the nail went through the soft anterior parts the palm being upwards, the thumb would bend sharply and would be exactly facing the palm by the contraction of the thenar muscles" (see below):
[Above: Cross-section of the wrist, palm facing upwards, with simulated Roman nail having already passed through "the soft anterior parts", including the median nerve, and about to enter Destot's space between the hamate and capitate carpal bones: "Relevant Wrist Anatomy," joint-pain-expert.net]
It is difficult not to think this was a deliberate attempt to mislead his readers by Zugibe, who would have been thoroughly familiar with the anatomy of the human wrist, and so must have known what Barbet meant, but chose to misrepresent it, so that his unsuspecting readers would prefer his hypothesis over Barbet's.Second, Barbet never claimed that there was complete "severance of the median nerve". Obviously if a nerve is completely severed, then it cannot conduct any nerve impulses at all to the muscles it serves, and in the case of the hand's median nerve, if completely severed, it could not cause the thumb to flex. What Barbet claimed, as can be seen above, was that the hands' median nerves were "seriously injured by the nail" in that they were incompletely severed, "sometimes halfway and sometimes two-thirds of the way across":
"Now, dissections have revealed to me that the trunk of the median nerve is always seriously injured by the nail; it is divided into sections, being broken sometimes halfway and sometimes two-thirds of the way across ..." (Barbet, 1953, p.118. My emphasis)
Zugibe was well aware that this is what Barbet claimed, because as we saw above, he himself states:
"Barbet made another serious error, claiming that when he drove the nail through Destot's Space, anywhere from 1/2 to 2/3 of the trunk of the median nerve was severed." (Zugibe, 2005, p.74. My emphasis).
So again, it is difficult not to believe that Zugibe was not deliberately and dishonestly trying to mislead his readers (as I for one was mislead, until I went back and read what Barbet actually wrote and checked it against diagrams of the hand's bones and nerves).
From the foregoing evidence of Zugibe's apparent dishonesty, it is difficult to place any credence on his claim that":
"2) even if it did [the median nerve ... pass through Destot's Space (which Barbet did not claim)] and was injured, there would be no flexion of the thumb."
First, Barbet carried out the experiments and found that there was flexion of the thumbs. So Zugibe was, in effect, calling Barbet either a liar, or incompetent (along with those, like Medical Examiner Bucklin who agreed with Barbet), without performing the experiment himself.
Second, as we saw above, the late Dr. Robert Bucklin, a Medical Examiner of Los Angeles County, agreed with Barbet's finding. Indeed, Dr Bucklin later wrote in a 1982 paper that Barbet's experiment "has been repeated by others" and he added that damage to the median nerve may cause the thumb to "either be adjacent to the hand or flexed over the palm":
"The thumb may either be adjacent to the hand or flexed over the palm A nail can be easily driven through the bones of the wrist, separating these bones but not producing fractures. This was done experimentally by Barbet and has been repeated by others. Since the right wrist is covered by the left hand, no puncture mark is visible on the right wrist. The fact that on the imprint of the hands no thumbs are clearly visible is explained by the penetrating pointed objects passing through the wrists having damaged the median nerve. The motor function of the median nerve is to produce flexion of the thumb. The thumb may either be adjacent to the hand or flexed over the palm." (Bucklin, R., 1982, "The Shroud Of Turin: Viewpoint of a Forensic Pathologist," Shroud Spectrum International, December, p.7).
So again, Zugibe was wrong and Barbet's hypothesis stands unrefuted: the thumbs of the man on the Shroud, are not visible because of damage to the hand's median nerve!