Mortis patch rigor

Rigor mortis begins 3 to 4 hours after death, then reaches its peak in about 12 hours, and then lasts for about 24 to 48 hours.

At the hour of death, there will be primary flaccidity. First, it appears in involuntary muscles, and then it starts in the eyelids, lower jaw, and neck. It raises upwards to the muscles of the face and down to muscles of the chest, upper and lower limbs, abdomen, and lastly in fingers and toes.

In the case of limbs, they expand from below. Rigor mortis disappears in the same order in which it appears. Both the appearance and disappearance of rigor mortis are gradual. The mechanism of rigor mortis after death shows that adenosine triphosphate ATP gets destroyed gradually, which causes an increase in the collection of lactates and phosphates in muscles.

Loss of ATP causes an increase in calcium levels in sarcomeres, and muscle contraction occurs. When adenosine triphosphate gets lower than 85 percent, overlapping portions of myosin and actin filaments combine as rigid links, leading to rigor mortis. The early post-mortem phase is probably the most important time period for PMI estimation as most medico-legal cases are examined in this time period.

This period is also where the estimation of time since death is most relevant in establishing the timeline of events and developing a theory of circumstances of death.

This period runs from 3 to 72 hours after death. The early post-mortem phase is most frequently estimated using the classical triad of post-mortem changes — rigor mortis, livor mortis, and algor mortis. Algor mortis is the cooling of the body after death, primarily due to loss of homeostatic regulation by the hypothalamus, in conjunction with the loss of heat to the environment by conduction, convection, and radiation.

Algor mortis is the most accurate method of estimating TSD in the early post-mortem phase. However, it involves a cumbersome procedure and requires intensive knowledge and research before it is accurately usable in the field; this is due to the numerous factors that affect the temperature gradient between body temperature and ambient temperature, the most inherent being the differences in the temperatures of different localities at different points of time.

A rule of thumb states that there is a decrease of 1. While they have been consistently used, nomograms for brain temperatures have also been developed by Brinkmann et al. Rigor mortis is the post-mortem stiffening of muscles caused by the depletion of adenosine triphosphate ATP from the muscles, which is necessary for the breakdown of actin-myosin filaments in the muscle fibers. Actin and myosin are components of the muscle fiber and form a covalent bond during contraction.

The cessation of oxygen supply causes the stoppage of aerobic respiration in the cells and leads to a lack of ATP production. While rigor mortis develops simultaneously in all muscle tissue in the body, voluntary and involuntary, the size of the muscle determines the perceptibility of changes by the examiner. Smaller muscles over the face — around the eyes, around the mouth, etc. Rigor mortis appears approximately 2 hours after death in the muscles of the face, progresses to the limbs over the next few hours, completing between 6 to 8 hours after death.

This process begins in all the cells at the same time. However, just like with the appearance, this change is perceptible first in the smaller muscles of the face, followed by muscles of the upper limbs, and finally, the large muscles in the lower limbs. Rigor mortis generally disappears 36 hours after death, followed by a phase known as secondary flaccidity. The final change in the classical triad is livor mortis, which is the purplish-blue discoloration of the skin in the dependent parts of the body due to the collection of blood in skin vessels caused by gravitational pull.

Hypostasis develops as spots of discoloration within half an hour to 2 hours. These spots then coalesce to form larger patches, which further combine to form a uniform discoloration of the body's dependant parts that have not been subject to pressure, which appears from 6 to 12 hours.

This fixation is confirmed by applying pressure with thumbs and is traditionally used to denote a PMI greater than 12 hours. Other methods of estimating TSD in the early phase include histo-morphological and Bio-chemical analysis. Total and differential blood counts and the microscopic morphological examination of blood have been described as a method for estimation of the TSD. All blood cells were not identifiable beyond 84 hours after death. Similarly, blood cell counts were also found to decrease beyond 84 hours after death.

Dermo-epidermal separation is seen 9 hours after death, while dermis showed rarefaction and disintegration 6 and 18 hours after death, respectively. The glycogen in the basal membrane of the sweat glands, the secretory cells cytoplasm, and duct cells gets depleted within 3 hours PMI and leads to PAS-negative cells on histology. The basal membrane, however, continues to show a magenta staining up to 18 hours post-mortem. The eccrine sweat glands show vacuolation after 3 to 4 hours of PMI, and cells appear to have completely disintegrated 15 hours after death.

The sebaceous glands appear normal till 18 hours post-mortem, seen as a separation of the layers and disintegration of hair papilla. The cells are primarily lymphocytes with a significant fraction of macrophages, which become vacuolated and unidentifiable after 12 hours.

Biochemical blood assessment is non-significant in the immediate post-mortem phase due to the lack of cellular death. On the other hand, cellular death makes biochemical blood assessment in the early phase extremely difficult. Also, there is the redistribution of electrolytes from the cells into the plasma and serum, resulting in varying changes in the levels of these electrolytes. These variations and their implications are studied in the emerging field of thanato-chemistry.

The biochemical assessment has been useful for estimating PMI from vitreous humor, synovial fluid, pericardial fluid, urine, and cerebrospinal fluid. Numerous factors, however, need to be accounted for when examining the PMI based on biochemistry, including, but not limited to, age, gender, biological background, lifestyle, cause of death, and a whole range of other intrinsic and extrinsic factors. Only a few biochemical markers out of were found to have had sufficient investigation with these considerations — namely potassium, sodium, urea as well as chloride, magnesium, hypoxanthine, and cardiac troponin T.

Assessment for their potential for use was found to be alarming, with 0 zero biochemical markers being judged to have had suitable research and suitable for use. Six were found to be suitably researched but not suitable for practical use. Meanwhile, 18 were found to have been poorly investigated and not suitable for the application, and a further biochemical markers did not have sufficient information.

Supra-vital reactions have also been proposed as a means of estimation of PMI. The determination of the supra-vitality period, therefore, can help assist in the estimation of PMI. For this method, Madea defines the PMI into four stages - the latency period, where despite stoppage of circulation, the tissue still performs aerobic respiration till the depletion of its stores — the survival period, where there is loss of tissue function, but they can be re-activated using external stimuli, e.

Madea defines supra-vitality as the survival period of tissue after complete, irreversible ischemia. This concept states that the survival period encompasses the latency period. The resuscitation period encompasses both the latency period and the survival period and the supra-vitality period includes all the other three.

Supra-vitality is also different from the resuscitation period in that the tissue is excitable irrespective of recovery of function. As an example, the resuscitation period of skeletal muscle is approximated to be 2 to 3 hours, but the supravital period in some cases may extend to 20 hours.

Similarly, cardiac muscles have a resuscitation period of 3. A ratio of relaxation time and maximum force, called force-related relaxation time, was reliable for estimating the PMI. Therefore, the supra-vital reaction examines the idio-muscular or local contraction and not the contraction of the entire muscle. The late post-mortem phase is when the body tissue starts disintegrating and is primarily describable as decomposition or putrefaction, adipocere formation, mummification, or skeletonization.

The body primarily undergoes decomposition or putrefaction, resulting in greenish discoloration, bloating due to gas formation, and liquefactive necrosis. The decomposition of remains is dependent on the climate, the season, body weight, and clothing. We thank the Peenya Police Officers from Bangalore for providing the photographs.

We also thank Dr. Shivaramu, Dr. S, Dr. Saralaya and Dr. Naveenkumar, of Bangalore, for their valuable suggestions and support. Source of Support: Nil. Conflict of Interest: None declared. National Center for Biotechnology Information , U.

Rajesh , 2 and J Kiran 3. S Harish 1 M. Author information Copyright and License information Disclaimer. Address for correspondence: Dr. E-mail: gro. This is an open-access article distributed under the terms of the Creative Commons Attribution-Noncommercial-Share Alike 3. This article has been cited by other articles in PMC.

Abstract We report a case in which the dead body was found with rigor mortis in an unusual position. Keywords: Crime scene, disposal of dead body, homicide, rigor mortis, scene of occurrence, unusual position. Open in a separate window. Figure 1. Figure 2. Direction of the salivary stains on the face, toward the left, defying the gravity. Observations from the photographs The location was an open ground with a flat surface.

Clues after considering the photographs The scene of occurrence of death is unlikely to be the place where the dead body was found. The death is homicidal in nature.

The clue about the scene of death occurrence In the present case, it can be presumed that dead body was positioned into an unusual posture, prior to the onset of the rigor mortis. It raises upwards to the muscles of the face and down to muscles of the chest, upper and lower limbs, abdomen, and lastly in fingers and toes. In the case of limbs, they expand from below. Rigor mortis disappears in the same order in which it appears. Both the appearance and disappearance of rigor mortis are gradual.

The mechanism of rigor mortis after death shows that adenosine triphosphate ATP gets destroyed gradually, which causes an increase in the collection of lactates and phosphates in muscles. Loss of ATP causes an increase in calcium levels in sarcomeres, and muscle contraction occurs.

When adenosine triphosphate gets lower than 85 percent, overlapping portions of myosin and actin filaments combine as rigid links, leading to rigor mortis. In rigor mortis, there will be an increase in lactic acid and a decrease in hydrogen ion concentration. When the lactic acid concentration reaches 0. The stiffness continues until the muscle protein decays.