Interestingly, the nail at the wrist would have penetrated a nerve and caused the thumb to snap into the palm. The thumbs of the man in the Shroud are hidden due to this nailing.
The Shroud does show a wound to the side, as where the soldier's lance would have pierced the heart of our Lord. The spear passed through the fifth and sixth ribs, and pierced the pericardium and the right auricle, causing the flow of blood and pericardial fluid.
Blood stains around the forehead and nape of the neck could be attributed to the crown of thorns.
Blood stains also appear across the back, alternating right and left shoulders, and on the buttocks due to scourging. The scourge wounds fan-out, which makes sense since the flagellum used by the Romans had two or three leather throngs with small lead balls or hooks at the end to gouge the flesh of the victim. Clearly, the victim was whipped very methodically, and over 120 wound sites are present.
The blood is definitely human blood. The STURP team determined that the stains were human blood of the AB group. This finding has been corroborated by others: Professor Pierluigi Baima Bollone, Professor of Medicine at the University of Turin, reported in 1978 that the blood stains were indeed human blood with traces of aloes and myrrh and belonging to the group AB. French geneticist Professor Jerome Lejeune also concluded that the blood sample he obtained was human hemoglobin.
Another intriguing point is that the blood marks on the Shroud are clear and red, not dark brown as typical of dried blood. Also the blood stains are complete without signs of flaking off. Dr. Gilbert Lavoie suggested that what appears on the Shroud is more an exudate from clotted wounds rather than whole blood. Likewise, Dr. Alan Adler explained that the torture, scourging, and crucifixion suffered by the man produced a hemolysis (break-up of red blood corpuscles), which would produce the lasting red color of the exudate.
No pigments, paints, dyes, or stains have been found in the fibrils. X-ray flourescence and microchemistry on the fibrils eliminate the possibility of paint being used as a method of creating the image, and ultraviolet and infrared evaluation have confirmed these studies. If paint had been used, it would have penetrated through the top fibers onto the lower fibers in the herringbone weave; however, the image is only on the top fibers with the lower fibers being untouched.
Also, the image was resistant to bleaching and other standard chemical agents that would have reacted with paint or some other medium.
Enhanced photography has also produced exciting evidence. The studies have included photographic enlargements and computer analysis of shapes, colors, and shadows. Also, a microdensitometer was used which measures very faint changes in lightness and darkness. In 1979, Father Francis L. Filas, S.J., of the Loyola University of Chicago, using the STURP research, observed on the right eyelid of the man four letters UCAI which formed a crown around the crook of an augur's staff. This image corresponds to the symbol on a small coin struck in A.D. 29 during the procuratorship of Pontius Pilate (AD 26-36). The ancient Jews used coins to hold down the eyelids. Also, Father Filas noted that later Byzantine coinage was engraved with an image of Christ Pantocrator which bore a striking resemblance to the facial image of the Shroud, which would attest to the Shroud's presence in Constantinople.(...)