Injuries and violence related fatalities are subjected to medico-legal examinations in Nepal [1]. Autopsy still remains the “gold standard” by which the physician’s clinical diagnosis is confirmed, amended or refuted. It is the most reliable and accurate instrument for investigation of injuries [2]. Early recognition of the injuries and providing an immediate treatment are mandatory for saving the lives of many of these patients [3]. If they are overlooked and neglected, their situations would eventually have medico-legal implications [4].
A blunt impact on the upper abdomen can compress and injure the liver and spleen before a significant whole-body motion occurs. In the liver, compression increases intra-hepatic pressure and it generates tensile or shear strains. If the tissue is sufficiently deformed, laceration of the major hepatic vessels, which occurs, can result in a haemoperitoneum. Abdominal deformation also causes lobes of the liver to move relative to each other, stretching and shearing the vascular attachment at the hilar region [7]. An accurate and a detailed understanding of the frequency and types of injuries leads to more accurately targeted measures of prevention, diagnostic algorithms, education and capital investment management.
Materials and Method
This was a hospital based, cross sectional study which was conducted on the autopsies showing the evidence of liver injury conducted in the mortuary of a tertiary hospital in eastern Nepal. All the cases which were handled within one year time (14.04.2010 to 13.04.2011) were included in our study. The number of cases was 46. In each case, a routine medico-legal autopsy was performed and all injuries were noted. The cases were studied in detail for liver injuries, which included age, sex, associated injuries, site of the injury, description of the injury, etc.
The liver injuries were described according to the Organ Injury Scale and Abbreviated Injury Scale (AIS) 2005 update 2008. The AIS is an anatomically based, global severity scoring system that classifies each injury into nine distinct anatomic regions on a six-point ordinal scale (1 is a minor injury and 6 is a maximum injury which is currently untreatable) [8]. The AIS grading can be equilibrated to the Organ Injury scale. The Organ Injury Scales were developed by the Organ Injury Scaling Committee of the American Association for the Surgery of Trauma (AAST). Each organ injury can be graded from 1 to 6. Grade 1 is assigned to the category of a least severe injury, while grade 5 is assigned to the most severe injury in which the patients have chances for survival. Grade 6 injuries are, by definition, not salvageable and they are severe enough to claim the patients’ lives [9, 10][Table/Fig-1]..
Inclusion and exclusion criteria: All the autopsies which showed liver injuries which were caused by mechanical trauma were included in our study. The bodies that were decomposed and those where cause of trauma was unknown, were excluded from the study.
Data Collection Tools: Data was collected systematically in a detailed proforma which was developed for the post-mortem evaluation of victims who sustained liver injuries. All collected data was compiled and entered into the Microsoft Excel. Its analysis was done by using SPSS (Statistical Package for Social Sciences), version 17.0. Observations were recorded, analyzed and discussed.
Results
A total of 479 autopsies were performed in the Department of Forensic Medicine and Toxicology in the study period. Among them, 122 were road traffic accidents (RTA), and 49 other mechanical traumatic causes. Some forms of liver injuries were noted in 46 cases. Among the 46 autopsy cases with liver injuries, 36 (78.3%) were males and 10 (21.7%) females. Their mean age was 33.87 years, with a standard deviation of 15. The commonest age range of the victims was 16-30 years, which constituted 23 (50%) cases, followed by the age group of ≥ 45 years which constituted 12 (26%) cases and 31-45 years which constituted 9 (19.6%) cases, while age group of 0-15 years constituted the least number, i.e., 2 (4.3%) victims.
The injuries had resulted from blunt trauma in 41 (89.1%) of the cases, the most common of which were RTAs, which constituted 37(80.4%) cases overall and 90% of the non-penetrating cases. The other causes of blunt hepatic injuries were fall from a height in 3 (7.31%) cases, and in one case, the injury had resulted from an assault with the use of a blunt weapon. The contribution of penetrating injuries was 5 (10.9%) cases, among which stab injuries and firearm injuries were the causes in two cases each and in one case, a projecting iron rod had caused the injury during a fall from a height.
Liver Injuries were graded by using Organ Injury scale and AIS 2005 and the results have been shown in [Table/Fig-2].
| AAST Grade* | Description | AIS 2005 |
|---|
| I | Contusion; Haematoma: Subcapsular, <10% surface area Laceration: Capsular tear, >1cm parenchymal depth | 2 2 |
| II | Haematoma: Subcapsular, 10-50% surface area Laceration: Capsular tear, 1-3 cm parenchymal depth, <10cm long | 2 2 2 |
| III | Haematoma: Subcapsular, ≥50% or expanding; ruptured subcapsular or parenchymal Haematoma; intraparenchymal Haematoma >10cm or expanding Laceration: >3cm parenchymal depth | 3 3 |
| IV | Laceration: Parenchymal disruption involving 25-75% of hepatic lobe or 1-3 couinaud’s segments within a single lobe. | 4 |
| V | Laceration: Parenchymal disruption involving >75% of hepatic or >3 couinaud’s segments within a single lobe Vascular: Juxtahepatic venous injuries: i.e., retrohepatic venacava/ central major hepatic veins. | 5 5 |
| VI | Vascular: Hepatic avulsion. | 6 |
*Advance one grade for multiple injuries up to grade III
Grading of liver injuries
| Liver Injury Scale | AIS 2005 | Number of Victims (%) |
|---|
| Grade I | 2 | 6 (13.0) |
| Grade II | 2 | 8 (17.4) |
| Grade III | 3 | 14 (30.4) |
| Grade IV | 4 | 4 (8.7) |
| Grade V | 5 | 11 (23.9) |
| Grade VI | 6 | 3 (6.5) |
| Total | | 46 (100) |
Laceration of the liver was the most frequent finding that was evident in 34 (73.9%) cases, followed by haematoma, which was seen in 8 (17.4%) cases. Combined haematoma and laceration was seen in 3 (6.5%) cases, while haematoma, as a sole manifestation, was evident in only one case.
Right lobe of the liver was mostly injured. The involvement of right lobe was seen in 34 (73.9%) cases, that of left lobe was seen in 5 (10.9%) cases and a bilobar involvement was seen in 7 (15.2%) cases. The convex surface was the most common site which was affected by all the types of injuries. Its involvement was seen in 27 (58.7%) cases. Injuries on the inferior surface were detected in 12 (26%) cases and on those on the diaphragmatic surface were detected in 7 (15.2%) cases.
[Table/Fig-3] shows the association of liver injuries with other abdominal and pelvic injuries. The association of other regional injuries has been depicted in [Table/Fig-4].
Associated abdominal and pelvic injuries
| Injuries | Number (%) |
|---|
| Isolated Liver Injury | 14 (30.4) |
| Mesentery | 13 (28.0) |
| Spleen | 10 (21.7) |
| Kidneys | 10 (21.7) |
| Diaphragm | 10 (21.7) |
| Large intestine | 6 (13.0) |
| Pelvic bones fracture | 5 (10.8) |
Associated Injuries on the body regions
| Injuries | Number (%) |
|---|
| ≥2 Body regions | 22 (47.8) |
| Thorax only | 11 (23.9) |
| Extremities only | 5 (10.9) |
| Head only | 2 (4.3) |
Discusion
The most vulnerable age group in our study was 16-30 years. This age group leads a more active life and is at the peak of its activity, having the tendencies of taking risks, alcoholic intoxication, etc. thereby subjecting itself to the dangers of accidents and injuries. Males were predominantly involved in our study and the male: female ratio was 3.6:1. The fact that males are usually the earning members of the families makes them more mobile and thus, vulnerable to accidents and construction and industrial mishaps, as compared to females who mostly indulge in household chores. A similar pattern was shown by other studies also [3, 11–16].
Blunt trauma was the predominating trauma mechanism in the study population. The overwhelming bulk of liver injuries were caused by road traffic accidents. Non-penetrating injuries, as the common cause of liver trauma, has also been mentioned in other similar studies [3, 11, 14–16].
The predominant injury site was the right hepatic lobe in our study. This result was similar to that of many studies which had been conducted earlier [3, 12, 15–17]. The greater pre-ponderance of right sided liver injuries could be explained on the basis of the bulkier size of the right sided liver, which could have led to a greater vulnerability of it bearing more impact. The right lobe of liver is not well supported anatomically, which can be another explanation. In the fatalities with liver injuries, laceration was the most common nature of injury which was present in our study. It can be attributed to the friable consistency of the liver. As was highlighted in our study, upon the commonest sites and type of hepatic injuries, it can be helpful in timely intervention and early treatment of the patients. Convex surface was the commonly affected site. This finding was supported by those of other similar studies [15, 16].
Shakeel A et al., [11–12] didn’t find any Grade V and VI injuries. This was in contrast to our study findings, as our study included only the fatal group. Our results were similar to those of P Tavling et al., [12] They had studied autopsies with liver injuries. Assessment of the degrees of hepatic injuries may be helpful in determining the outcome and treatment quality at different centres. The medico-legal expert who conducts the autopsy, when he/she is called upon to present his/her autopsy findings in court and to express an opinion regarding the amount of force that may have been applied in order to produce the traumatic lesions which were noted, has to rely on a subjective interpretation of the findings and this may vary from pathologist to pathologist. The scientific grading of injuries provides uniformity among the pathologists.
Liver injuries occur in combination with other abdomino-pelvic injuries, commonly with mesenteric, diaphragmatic and splenic injuries. They can also be associated with multiple regional injuries. P Tavling et al., [12] also reported similar findings. As liver injuries increase in severity, other organ systems may become involved and so, total mortality may result from the cumulation of all damaged organs. This also emphasizes the need of a proper monitoring of the victims of trauma.
Conclusion
Laceration is the most common liver injury among autopsy cases. Right lobe is mostly affected, convex surface is the most vulnerable site and grade III injuries are the most common ones. Liver injuries are frequently associated with other abdomino-pelvic organs and multiple regional injuries. Proper identification of hepatic injuries, with a timely response to victims of such trauma and improvement of emergency services in the hospital, may help in saving human lives in a better manner.
*Advance one grade for multiple injuries up to grade III