For July 1999 issue

SCIENCE IN CRIME DETECTION

Deaths Due to Head Injury

‑Dr. Anil Aggrawal

I have often been called upon to examine cases where death has apparently been due to direct violence. By direct violence, I mean a situation where a person knowingly and intentionally hits a person directly over his body in order to kill him. Deaths due to automobile accidents may also be considered under this category, as they also cause direct violence. Many such injuries are found over the head, as it contains one of the most delicate portion of the body – the brain. Once the brain is dead, the person is considered dead. In this installment therefore, I would confine myself to deaths caused by injuries to the head.

These cases are not very difficult to detect. In most such cases there are usually lacerations or bruises upon the surface of the body. However, the absence of these marks should not lead one to believe that direct violence or blunt force could not have caused the death. Many insurance policies require that where claims are made for accidental death that there must be external signs, such as bruises or lacerations, to indicate that death was accidental. It is entirely possible and not infrequent that a person may suffer such a death with no such indications whatever on the surface of the body. This is important to remember. I have seen many younger doctors committing mistakes on this point.

Since automobile accidents have become so frequent, the number of deaths from this cause has grown to such proportions that they are one of the major problems that come to the attention of the coroner or medical examiner.

Injuries to the Head

The scalp is one of the most frequent sites of injury on the body. Since the scalp overlies the hard skull underneath, it may be lacerated by blunt force in such a way that one would think the victim had been struck by a sharp instrument. For instance a fall on a smooth surface like ice or a hard floor may result in a clean straight laceration. This fact has been misinterpreted in many important cases.

The skull in an adult is a solid bony structure and injuries to it do not cause death unless the brain underneath has been damaged. The mere fact that the skull may not be fractured does not indicate that there may not be serious brain damage; on the other hand a fracture of the skull may occur, yet the damage to the brain be comparatively slight. The brain in a living person has a semi-solid consistency. It is difficult to handle the brain without its falling apart because of its weight. The spinal cord which extends down inside of the spinal column is of the same consistency and is actually a continuation of the brain stem. Consequently, it often happens that when a person falls, striking his head on a hard surface, the brain tends to be compressed on the side of the injury, and is torn away from the opposite side so that the bulk of the brain damage may occur on the side opposite to that which received the blow. This phenomenon is known to medical men as countercoup. When a person is struck a blow on the head by an instrument such as a hammer, billy, or club with such violence as to cause injury to the brain, that injury is usually located directly beneath the point of impact. The distinction between these two types of brain injury is of major importance and the autopsy surgeon always tries to determine whether the damage was due to countercoup or direct impact.

As a general rule injuries to the brain in the back part of the head are more likely to cause death than injuries to the brain in the forward part of the skull. It is not uncommon to see severe injuries to the front part of the head with a massive fracture of the skull and actual oozing out of the brain substance, without the person even losing consciousness. Similar injuries to the back part of the head are usually rapidly fatal.

Another situation that is not infrequent occurs when a person suffers what appears to be a slight wound of the head. He may be stunned for a few moments, but soon feels much better. A few hours later he loses consciousness and may die before medical aid can be summoned. In these cases there has usually been a rupture of one of the arteries supplying the membranes that cover the brain, called the meninges. A slow oozing takes place until a large clot is formed, and the pressure from this eventually causes death. For this reason the doctor generally keeps a person in bed under close observation for a period of at least twelve hours following even a minor head injury.

A severe blow on the chin may result in a fracture of the skull with severe brain injury. The force of the blow is transmitted to the point where the jaw hinges on the skull, often causing death. This occasionally happens in boxing matches.

Repeated blows on the head over a long period of time may cause the formation of small areas of scar tissue throughout the brain substance, giving rise to unsteadiness of gait and mumbling speech. The victim is commonly known as “punch drunk”. Concussion of the brain is a term indicating a severe shaking up of the brain substance, without causing major lacerations or bleeding. The victim may be unconscious for a considerable period of time but generally recovers completely.

Subdural Hematoma

After severe head injury sometimes a large clot forms over the surface of the brain but underneath the tough membrane which encloses the brain substance. Usually it is located on the side of the brain in front of and slightly above the ear. Particularly in elderly people this condition may result from comparatively minor violence and sometimes there is no history of any head injury whatever.

The clot becomes encapsulated after a few days but tends to gradually expand with increasing pressure and displacement of the brain. If the condition is recognized it may be removed surgically with complete recovery to the patient. This can be responsible for death too. This clot is technically known as subdural hematoma. In many cases of head injury, subdural hematoma is seen.

Now that you have understood the basics of head injury, I will describe one interesting case which I solved by examining properly the subdural hematoma. Raju was a drunkard, and had taken alcohol on one night in excess. He went to his enemy Gajju after taking too much alcohol and picked up a fight with him. Gajju told him repeatedly to go away. He told him that he was tipsy, and that he would talk to him only the next day. But Raju was intent on picking up a fight with him. He had some old score to settle with Gajju. He picked up an iron bar and wanted to hit Gajju with it. Gajju caught hold of the iron bar. In the scuffle that ensued, Raju fell down and sustained head injury. He was immediately hospitalized.

Meanwhile the police arrested Gajju on the charge of murder. Gajju said that he had no fault of his own. According to him Raju had come to him in a tipsy state and he was bent upon picking up a fight. But the police did not believe him, and arrested him. They began torturing him too in order to get his confession.

Raju remained alive for about ten days after which he succumbed. The body was sent for post-mortem to a young doctor, who had been my student. Of course the main purpose of the post-mortem was to establish the cause of Raju’s death, but another important thing was to establish whether Raju was drunk at the time of scuffle or not. If it could be proved that Raju was indeed drunk at the time of scuffle, then Gajju’s story would be believed. His lawyer was sure, that in such a situation he would save his client.

Generally in order to determine whether a person was drunk at the time of his death, we do his blood examination. At the time of autopsy, we take blood from one of his leg veins and send it for chemical analysis. If the blood shows significant levels of alcohol in it, we can safely tell the court that the person was drunk at the time of his death. Of course, the levels of alcohol in the blood also matter.

But after a person has consumed alcohol, the body immediately begins to destroy it. In about 4-5 hours time, almost all the alcohol that the person has consumed has been destroyed. This is the reason, why the person becomes sober after 4-5 hours of a drinking session.

In the case of Raju, he had survived for more than 4-5 hours; in fact for ten days. So whatever alcohol was there in his blood had already been destroyed. Had the treating doctor been wise enough to preserve some blood from Raju as soon as he came to the hospital, and sent that blood for alcohol determination, that would have been alright. The doctor in fact did take blood from Raju, but he sent it for different tests such as blood glucose, urea, and so on. These are the standard tests that are done in all emergency cases. The doctor on duty at the emergency was naturally not trained in forensic medicine and had forgotten to take the blood for alcohol determination.

The young doctor to whom the body was sent for post-mortem was very confused. He gave me a call and asked me what he should do. I was on summer vacation, but since this was an important case, I reached the mortuary. I found that Raju had subdural hematoma, the blood clot which forms in the brain, about which we have talked earlier. Now this blood which collects in the brain actually comes out of the system, so the alcohol in that blood clot doesn’t get destroyed. The body enzymes, responsible for the destruction of alcohol in the blood, have no access to the blood clot in the brain, so any alcohol present in the blood must remain in the blood clot, even if the person died several days later. I immediately advised the young doctor to send the blood clot from the brain for chemical analysis. Sure enough this clot was found to contain lot of alcohol, and we could prove in the court quite convincingly that Raju had in fact taken alcohol. And Gajju’s lawyer armed with this new finding was able to save Gajju. When Gajju heard that he had been saved by forensic medicine, he came to us and thanked us profusely, but I asked him to thank forensic medicine. Another man had got justice because of the application of forensic medicine!

(Note: In order to protect the identities of the individuals, the names have been changed.)

Captions to figures:

FIG. 1: Death due to head injury, Notice the bleeding from the ear which always indicates the possibility of a fracture of the base of the skull.

FIG. 2: The base of the skull of the victim shown in Figure 1. The skull cap and the brain have been removed. Note the long fracture line extending from ear to ear across the base of the skull.

FIG. 3: Death due to a blow on the head with an iron bar. Extensive scalp laceration with fracture of the skull. The victim was "taken for a ride" and while riding in the front seat was struck from the rear.

Fig. 4: Murder and robbery. The victim was struck over the head by one of the timbers shown in the photograph. Note the pockets turned inside out.

FIG. 5: The face of the victim shown in Figure 4

(Dr. Anil Aggrawal, M.D. is a Professor of Forensic Medicine at the Maulana Azad Medical College, New Delhi)