Written in Bone

by Sue Black

  At the postmortem examination, it was noted that the extent of the trauma to his skull was equivalent to someone falling from the fourth floor of a building or being subjected to a high-velocity impact in a vehicle collision. Yet it was clear that Colin had died where he fell, in the back bedroom of his bungalow. There was no significant blood spatter in the room, no disrupted furniture and no obvious weapon. It was a genuine riddle. The murder was well publicized but it seemed nobody had seen anything, nobody had heard anything and nobody could understand why anyone would do this to a defenceless old man who seemed not to have an enemy in the world. The cause of death was recorded as multiple trauma to the head and his body was released for cremation.

  I pored over the photographs and images. To develop a solid theory that works from every angle you need uninterrupted time and colleagues who will question every hypothesis you propose thoroughly, to help you to construct what is most likely, after all else has been discarded as implausible or impossible. In this regard we do have something in common with Sherlock Holmes. We all follow the maxim: “When you have eliminated the impossible, whatever remains, however improbable, must be the truth.”

  When undertaking a fracture analysis, we first look to establish the sequence of events that might explain the pattern of fragmentation and thus the nature of the attack. Once a first crack has occurred in the bone, the force of any secondary or subsequent fracture that intersects with it will dissipate its force into the void created by the first fracture. In this way you can seriate the injuries by determining which happened first, which second and so on. It is rare (and some insist not possible) for a subsequent fracture to jump over an existing fracture and continue on to the other side, but it can happen if the force is sufficiently great.

  The photographs of Colin’s face taken before the postmortem began showed a sizeable opening to his skull at the inner corner of his left eye. This was wide enough for that small section of the frontal lobe of his brain to be extruded on to the carpet in front of where he lay. The problem was trying to work out how this could possibly have happened.

  We knew from the neuropathologist that no object had penetrated the skull to cause the hole—the brain tissue had come out, but nothing had gone in—because of the absence of tracking marks on the brain. There was periorbital bruising around both eyes and some small grazes on his scalp, but little else. Nothing on a scale that prepared us for what we saw when we looked at the postmortem photographs taken once the scalp had been retracted and the underlying bone revealed. The fracturing was extensive. The neurocranium was in multiple fragments and fracture lines criss-crossed his skull like a spider’s web.

  The first thing we had to do was identify the primary fracture—the one that halted or impeded the progression of all the others. From the photographs and the X-ray images we were able to locate this at the back of his head. It had been caused by two blows, both leaving paired puncture wounds in the scalp, which had pushed the inner layer of diploic bone into the cranial cavity. The distance between the paired sharp marks appeared from the photos to be similar in both injuries, so we were content that the same weapon, something with two pointed projections, might have been used twice to hit him on the back of the head with tremendous power. Despite his advanced years, the bone at the back of Colin’s skull was quite thick and it would have taken some force to pierce not only the scalp but also the robust layers of diploic bone in this area.

  Reviewing the crime-scene photographs, we found some that showed a foot-operated bicycle pump, with two sharp projections at its base, lying on the floor of the spare bedroom. The distance between the projections looked consistent with the gap between the bone perforations on the skull, although as the pump had not been kept, or swabbed for blood, fingerprints or DNA at the time, we could not say for certain that this was the weapon used.

  We believed this double blow set up a horizontal fracture line that ran almost from ear to ear around the back of Colin’s head, which we were confident was the primary trauma site. Once you fix the first trauma in your mind, you can work forwards to the second one. In Colin’s case this was probably a blow to his face which corresponded with a bruising pattern just above his left eye and across the bridge of his nose. Already disorientated by the blows to the back of his head, he had possibly now been hit quite violently in the front of his face (perhaps punched, as the bruising suggested that the attacker may have been wearing a ring).

  This second trauma opened up a longitudinal fracture that extended in a relatively straight line from his eye to the back of his skull, where it terminated in the void created by the first fracture. There would probably have been very little blood visible at this stage. Although the skin was bruised, the punch was not likely to have caused the extensive open wound we could see at the corner of his eye.

  It was more difficult to seriate the third trauma as it was clearly a violent event resulting in massive fragmentation of an already unstable skull. We had to look to elsewhere in his body for evidence of what might have happened to produce such extensive damage. The PM report had noted bruising to the rhomboid muscles of the left shoulder, the short muscles that link the inner border of the shoulder blade to the vertebral column. In the crime-scene photos, we could see an old mattress propped up against the wall of the spare bedroom. We thought it possible that the attacker had swung Colin by his left arm, bruising and ripping his rhomboids in the process, and that the crown of his head had collided with this mattress, which would have cushioned the impact.

  It is not surprising that the SOCOs did not look for blood on the mattress as it might not have seemed to be relevant: the victim was, after all, lying on the floor with part of his brain excised. Like the bicycle pump, the mattress had not been tested and had been thrown away when the house was cleared.

  The force of the swing resulting in the contact between Colin’s head and the mattress might have been sufficient to rip his shoulder muscles and drive his vertebral column forwards through the hole at the base of his skull, causing the extraordinarily severe comminuted fracturing noted in the postmortem report. Not only would this shatter the base of his skull, it could explain the two radiating fractures, one on either side, which ran upwards towards the top of his head. The fracturing on the left was so extreme that it jumped both the first and the second fractures, and ultimately dissipated on the right side of his head. The internal bleeding from such an injury to the base of the skull would have been extensive as the fracturing passed through the large transverse venous sinuses and, as the pathologist confirmed, it would not have been consistent with survival. We can only hope that Colin was more or less unconscious by this time.

  Incredibly, that was not the end of his nightmare. We still had to account for the hole near his eye. There was a small contusion on the side of Colin’s head which seemed to match the pattern of the tread on a set of household steps standing in the room. Again, these steps were never swabbed for blood or DNA and had been destroyed with the rest of the contents of the room when the house was cleared. We believe that, after being swung against the mattress, he may have come to lie with his head on one of the steps, and that while he lay there, his head was stamped on, setting up paired horizontal fractures that ran across the front area of his head, from temple to temple.

  Perhaps he was then pulled to his feet and thrown to the floor, because it is unlikely that he would have been able to get up by himself. As he finally came to rest on his front, in the position in which he would be found, the entire base of his fractured skull swung like a hinge, ripping open the already damaged skin above his left eye. As he rocked forward on his rotund tummy, the sharp, fractured edges of the skull may have acted like scissors, snipping the left frontal lobe of his brain and expelling the tissue through the hole in his face and on to the carpet in front of him.

  Well, it was a theory. We interrogated and tested it from all directions, and it was anatomically plausible, if nauseatingly violent. It accounted scientifically for every singl
e fracture, and in a credible sequence. Feeling nervous, almost sheepish, about our convoluted proposition, we returned to the next cold case review to present our theory: that the victim was hit twice on the back of the head with the bicycle pump, punched in the face, swung by the arm into the mattress against the wall and stamped on before finally being thrown to the floor. Everyone listened quietly as we went through the order of events, explaining our reasoning and detailing what, had the evidence still been available, could have been done to check whether what we were suggesting was tenable or indeed possible.

  When we had finished, all eyes were on the pathologist, everyone sitting tight to see whether he would buy it. It was like waiting for a panel of judges to give you a score for your technique and performance. Eventually he nodded and said that, in the absence of any other alternatives, this was a possibility. But it remains to this day little more than supposition.

  There was one interesting codicil to this sad case, after a young couple on holiday in Spain got talking in a bar to a man from the part of the world where Colin lived. As the evening wore on and the drink flowed, the man started to regale the couple with stories of the often violent activities of his former paramilitary days. When they asked him if he had ever done anything he regretted, he said that on a visit to his home town he had killed an old man, and he regretted that very much. The holidaymakers thought little of it, apparently, assuming it was just the drink talking.

  But back at home, they were watching TV one night when Colin’s murder was featured on the BBC’s Crimewatch. Recognizing the location as the home town of the man they had met, they thought this was too much of a coincidence and decided they had better contact the police. They were hesitant, embarrassed even, about telling their story; the police, though, love a coincidence and they followed it up. The gentleman in question was known to them, but if it was true that he had murdered Colin, there was nothing they could do about it. He had, many years before, been given immunity from investigation and prosecution for turning Queen’s evidence on some serious historical crimes.

  After the programme was aired the press had a phone call—from the loyalist informant in question, who was and remains subject to death threats, he said, from the Ulster Volunteer Force. He insisted that the story he had told the couple in the Spanish bar had been misinterpreted, and that he had not been talking about Colin’s death. He admitted to having been in the area at the time of the murder but denied any involvement in it.

  To this day, we don’t know why the killer, whether it was the informant or someone else, thought it necessary to attack this old man, let alone in such a violent way. Colin was not known to the police, nor was he someone likely to be the target of a criminal grudge, such as an ex-police or prison officer. There was no known link between him and the informant now living in Spain.

  It is a pity that our evidence could not lead to an arrest but it at least provided some possible answers in what was a most perplexing case. And the work we did here—examining the evidence and trying to build a possible story that might explain the findings—is a big part of the forensic anthropologist’s job. It does not necessarily mean it will result in an offender being brought to justice or even that we will ever discover if we were right. The fact that a case will sometimes remain frustratingly unresolved is something I’d had to come to terms with much earlier in my career. It might not make good television drama, but it is how things are in the real world.

  ◊

  Once fully formed, there is little scope for the skull of an adult to change its shape. Each bone must fit snugly with its neighbour if it is to provide adequate protection. However, since growing bone is very plastic and malleable, the shape of a child’s head can be altered.

  Throughout history, various cultures have artificially modified the neurocranial part of the skull by moulding it in babies before the bones have “set,” either in response to some belief that a particular shape had a beneficial effect on a person’s thought processes or simply because it was more aesthetically pleasing. Among the higher social strata of certain tribes, such cranial deformation was seen for the rest of a child’s life as a badge of their social status.

  These alterations to the appearance of the skull were achieved by binding the baby’s head between wooden boards, or winding it with tight cloths or bandages, to produce the desired shape: sometimes elongated, sometimes conical, sometimes round. It usually began about a month after birth and continued for six months, perhaps even a year or two, until the fontanelles had closed and the deformation was largely irreversible. It is claimed that there was no neurological impact on the child, but I am sceptical.

  This procedure was practised across many disparate geographical locations and chronological periods, from the north and south Americas, to Iraq, Egypt, Africa, Russia and pockets of Europe and Scandinavia. In some cases, such as the “Toulousian Deformation,” which persisted in rural southern France until the early twentieth century, the purpose of the binding was simply to pad and protect the delicate skull and the deformity was merely a by-product of the tradition rather than its intended outcome.

  Whatever the shape of the skull, the vault can tell us a lot about an individual, particularly in relation to their sex, age and sometimes their ethnicity. Sex determination is usually associated with enlarged sites of muscle attachment in the male and a more gracile, less robust appearance in the female. There are few muscles that attach to the neurocranium, but if you palpate quite deeply into the midline space where the muscles of the back of the neck meet the bone at the base of the skull, you will probably feel a large lump of bone in the male, but not in the female. This is called the external occipital protuberance and it is generally more developed in the male as it is where a very strong ligament of the vertebral column—the ligamentum nuchae—attaches. This ligament helps to hold the vertebrae of the neck in alignment and the head balanced on the first cervical vertebra.

  An Australian university recently hit the headlines when they announced, on the strength of the results of a small study, that modern-day adolescents and young adults show enhanced growth in the region of the external occipital protuberance. The fact that the study was based on a sample size of only 218 did not deter them from opining that this was caused by young people adopting a “heads down” posture consistent with prolonged use of electronic devices. The Bronze Age skeletons I studied for my honours degree frequently had very well-developed occipital spurs, but no matter how hard I searched, I never found their mobile phones.

  Science may be wonderful but pseudoscience can be dangerous. It is very tempting to share our theories with the world but we must be careful not to extrapolate over-enthusiastically from limited observations. We cannot mislead an investigation or a courtroom with unproven information based on our own fanciful hobby horse.

  The little lumps of bone at the back of your ears, called the mastoid processes (from the Latin meaning “little breasts”), can also be a useful, though not infallible, indicator of sex. These are the site of attachment for the long sternocleidomastoid muscle that runs between the front of your chest and the back of your ear. You can see this muscle if you stretch your neck and twist your head to one side. The stronger the muscle, the larger the lump of bone, so mastoid processes tend to be much smaller in females than in males.

  There is evidence to suggest that if your mastoid processes point downwards, your earlobe will not be well defined (known as an “attached” earlobe). If the mastoid processes point forwards, you will probably have a well-defined, “free” lobe to your ear.

  Determining how old a person was when they died is difficult from the bones of the neurocranium alone, unless the subject is a young child. Once adulthood is reached, the joints, or sutures, between each of the vault bones start to fuse, and they become really no more than a general guide to whether a person is young or old.

  Sometimes, in the sutures between the different bones of the vault, accessory bones called Wormian bones may be found, which
are a marker for some conditions, such as Down’s syndrome and rickets. These are more common in some ancestral groups than others. For example, skulls of Asian Indian origin often contain an abundance of these extra little bony islands, while a very large, single extra bone at the back of the skull is often referred to as an “Inca” bone because of its prevalence among Peruvian mummies. This genetic predisposition to accessory bones in the skull sutures may provide valuable information in relation to ethnic origin.

  There might also be small pits on the inside of the skull cap, running in lines parallel to the keel from front to back. These are caused by arachnoid granulations, protrusions of the membranes that cover the brain, passing upwards to drain into the long vein or sinus that runs from the front to the back, inside the skull cap. The arachnoid granulations, which look like little cauliflower florets, drain cerebrospinal fluid, the fluid that bathes the brain, from the spaces between the coverings of the brain up into the central venous sinus known as the superior sagittal sinus, allowing it to be recycled into the venous system.

  With age, these depressions, known as granular foveolae, can become carved into the inner surface of the bone. If we see these, we may suspect that we are looking at the skull of an older individual. There was a fad at one time for trying to tell how old a person was by counting the pits, a bit like working out the age of a tree by counting the rings on its trunk, but foveolar counting is fantastical nonsense, even if it makes a good fable.

  It is also possible to predict some forms of deafness from the skull. The ear has three distinct sections to it, all of which are formed through different processes. The external ear includes the pinna (the outer flappy bit on the side of our head) and an opening into a canal leading to the eardrum, or tympanic membrane, which lies inside the temporal bone. If the external opening to the skull is absent, no sound waves can reach the eardrum and the person will be deaf.