An Osteological Case of Ancient Down Syndrome.

Skeleton in situ. Taken from Rivollat et al. (2014 Fig. 1 p.9).

Skeleton in situ. Taken from Rivollat et al. (2014 Fig. 1 p.9).

Scrolling through the International Journal of Paleopathology I came across an article entitled ‘Ancient Down syndrome: An osteological case from Saint-Jean-des-Vignes, northeastern France, from the 5–6th century AD’ by Rivollat et al (2014). During my studies I only came across Down Syndrome in genetics it is caused by a partially or complete third copy of chromosome 21, which is why it can be called trisomy 21. I didn’t know much about the physical manifestations of Down syndrome and therefore thought this article might be an interesting read.

Down syndrome is not well documented in human history and only two sub-adult cases have been reported in the archaeological literature. However, it is noted that there is a large amount of variation seen in cases of Down syndrome which makes it difficult to interpret. This study looks at a child’s skull, aged 5-7 years old, from a necropolis dated to 5-6th Century in France. The skull used for study was buried in the same manner as the other skeletons, indicating that it did not have receive different treatment at death.

The individual in question had good bone preservation, although most of the thoracic and lumbar vertebrae and the right hand were missing. This skeleton was originally excavated in 1989, were a photograph was taken in situ (see above). However, post cranial skeleton was lost after this which meant that the current study could only use the skull for analysis. This skull was then compared to 78 skulls of children of similar age and background to look for signs of Down syndrome.

By taking morphometric observations and comparisons some variation of the skull was found. To begin with the cephalic index was larger than the population mean of 83 measuring at 106.2. This is a ration between the maximum width of the head and the maximum length. In the skulls result indicated ‘ultrabrachycrany; i.e.. a skull which was short in length and wider than the norm. This large width of the cranium has been described in Down syndrome patients. The shape of the occipital bone also differs from normal, which is dish shaped, and is flattened in the skull. When observing the sutures the some of the metopic suture was still present and many lambdoid wormian bones were seen. Wormian bones are irregular, isolated bones located within sutures of the cranium, in this case the lambdoid suture which separates the occipital bone from the parietals. These features are also indications of Down syndrome. 

Anterior, inferior and lateral view of the skull, and superior view of the mandible. Taken from Rivollat et al. (2014 Fig. 2 p.9).

Anterior, inferior and lateral view of the skull, and superior view of the mandible. Taken from Rivollat et al. (2014 Fig. 2 p.9).

The mandible was also examined and measured and slight variations from the norm were found. These included a short mandibular symphysis and a narrowing of the breadth of the mandibular ramus. The angle of the jaw, the gonial angle, was slightly above normal. These are features which have been noted by Kisling (1966) and others referenced in the article. 

Another area of interest was the thickness of the skull vault and by using CT scans an accurate measurement could be taken. It was found that the thickness varied over the skull and at anatomical points were inside and outside of the normal range. At the bregma (point at which the coronal suture is intersected perpendicularly by the sagittal suture) and at the naison (intersection of the frontal and two nasal bones) the skull is of normal thickness. At the lambda (meeting point of sagittal and lambdoid sutures) the it is thinner but thicker at the euryon (point on parietal bone marking either end of the greatest transverse diameter of the skull).  The authors claim that the thinness at the back of the skull could be due to poor development of the bone and can be associated with Down syndrome. 

Profile outline of the Saint-Jean-des-Vignes skull and superimposition with another skull of the same age group (O, Opisthion; Ba, Basion; I, Inion; L, Lambda; Br, Bregma; N, Nasion; Ns, Nasospinal; Pr, Prosthion; ST, Sella Turcica). Taken from Rivollat et al. (2014 Fig. 5 p.12).

Profile outline of the Saint-Jean-des-Vignes skull and superimposition with another skull of the same age group (O, Opisthion; Ba, Basion; I, Inion; L, Lambda; Br, Bregma; N, Nasion; Ns, Nasospinal; Pr, Prosthion; ST, Sella Turcica). Taken from Rivollat et al. (2014 Fig. 5 p.12).

For those who are unfamiliar with the anatomical names and points of the skull visit the following web pages. These Bones of Mine provides images and diagrams of the bones of the skull whilst Anatomy Navigator provides a good overview of the anatomical landmarks.

Finally the study looked at the indention of the individual and the authors state that there are many features which are suggestive of Down syndrome. This includes a lack of development of the second lower deciduous premolar, which can affect up to  92% of Down syndrome cases. There is an indication of the onset of peridontal disease by the presence of bone remodelling of the alveolar bone, and which may have caused some tooth loss.

From these features a diagnosis of  Down syndrome was assigned, with a differential diagnosis of rickets and hydrocephalus. However these were ruled out due to the lack of porotic hyoerostosis for rickets and the presence of a normal cranial capacity for the child’s skull. Therefore the skull was given the diagnosis Down syndrome.

Whilst reading this article I did have some concerns about the diagnosis. At the beginning of the article the authors state that there have been few cases of Down syndrome found in the archaeological record, which means they have very few points of comparison. The second issue is that the diagnosis was based solely on the  skull, as the post cranial skeleton was missing.  As I know little about the physical manifestations of Down syndrome I did a quick search and it was very clear that these were very varied. There also appear to be few definite indicators of Down syndrome on the skeleton, and particularly lacking on the skull (this information was indicated from the following website).  taking this into account I think that it was a little unwise to assign the skeleton excavated in the study as having Down syndrome, it may have been more accurate to suggest a possible incidence of the condition.

In fairness to the authors they do state that ‘none of the features is pathognomonic’ (p. 13) however I may have been more conservative in the conclusion, particularly with the absence of the post cranial skeleton.

Rivollat, M., Castex D., Hauret L. & Tillier A. (2014). “Ancient Down syndrome: An osteological case from Saint-Jean-des-Vignes, northeastern France, from the 5–6th century AD.” International Journal of Paleopathology 7(0): 8-14.

Shattered Lives and Broken Childhoods: A Case Study of Child Abuse in the Archaeological Record.

In situ image and schematic of Burial 519. (Fig. 3 page 73). Image taken from Wheeler et al. (2013) article.

In situ image and schematic of Burial 519 (Fig. 3 page 73). Image taken from Wheeler et al. (2013) article.

Recently I have wanted to focus more on human pathologies in archaeology when I came across this article ‘Shattered lives and broken childhoods: Evidence of physical child abuse in ancient Egypt.’ I have never come across an example of this before and therefore gave it a read.

Child abuse is clinically classified as the maltreatment of a child by their parent or caretakers and can include physical, sexual and emotional abuse and physical and/or emotional neglect. In modern cases soft tissue damage and injuries are the most common presentation with 10 – 70% of children showing signs of skeletal trauma. In archaeology it is these latter injuries which may be seen however, it can be difficult to interpret them.

There are many reasons why confusion may occur when attempting to establish child abuse in skeletonised individuals. The first is establishing whether the trauma is a result of an accident or not. Traumas, such as fractures, may look the same no matter how they were obtained. However, the pattern of any pathologies identified, along with their process of healing, may be a good indicator. The use of physical discipline has also been recorded in the archaeology, for example during the Roman Period where it was not uncommon for children to be beaten if they made a mistake. There have been few examples of child abuse found during excavations, which may be a result of poor preservation and preparation, taphonomic processes or adult centred research and therefore does not mean that child abuse didn’t occur in past human societies, only that few cases have been confirmed.

This study by Williams et al. (2013) looks at an individual aged between 2 and 3 years old from the Romano-Christian Period from a cemetery in the Dakhleh Oasis, Egypt. In total 770 individuals were excavated, with a possible 4000 burials being present as indicated by an archaeological survey. From these 158 were 0 -1 years old, including the individual chosen for study. Burial 519 was undisturbed and had all of their teeth and bones, the preservation was also very good and therefore some hair, skin and nails survived. This individual was buried in the same manner as the other juveniles within the cemetery and it’s location did not distinguish it as being atypical. In order to study the individual full radiographs, micro-CT scans and tissue samples were taken, in addition to the standard ontological observations.

Burial 519 was aged using standard ageing methods by identifying the dental development and epiphyseal fusion of the individual. It was also observed that cribra orbitalia (an indication of a pathological deficiency) could be seen in both orbits. The authors noted that 60% of 1-3 year olds at the cemetery had this condition, with 95% of individuals having active lesions. The remaining pathologies recorded for the individual in Burial 519 related to fractures, a full summary of which can be found in Table 1, page 75 of the article.

image showing fractures and bone growth in the humerus and ribs (Fig. 5 p. 76). Image taken from Wheeler et al. (2013) article.

Image showing fractures and bone growth in the humerus and ribs (Fig. 5 p. 76). Image taken from Wheeler et al. (2013) article.

These fractures were found in both upper arm bones, the clavicle, two ribs, two vertebrae and the pelvis. The healing process of these injuries differ and therefore suggests that they occurred at different times. For example, both humeri have complete transverse fractures of the proximal third where the bone margins are slightly rounded and the trabecular bone has a smooth appearance. This indicates that the breaks occurred several weeks before death whilst the fractures of the 7th left and 8th right ribs are well healed. In contrast to these breaks the right clavicle has a complete transverse fracture where there are no signs of healing. From looking at these sites alone it is fairly clear that all of the injuries did not occur at the same time.

This pattern of fractures and healing is consistent with clinical pattern of skeletal trauma in victims of non-accidental trauma; i.e. physical child abuse. This point is expanded on in the article with particular focus on the clavicle. The article states that accidental clavicle fractures are rare in children under the age of two (Carty 1997) and are usually a result of violent shaking of the arms by causing sudden traction. In older children these fractures can occur by falling. When combined with information about the ribs and humeri fractures the conclusion of child abuse can be justified in the individual of Burial 519. Fractures found in the humeri can be associated with direct blows of high energy and the bone formation at the diaphysis, mentioned in the article, indicates the limbs being pulled forcefully when being shaken which caused the periosteum to be stripped from the bone. Finally, the ribs are good indication that child abuse has occurs as fractures to these bones are very rare, even in violent trauma. 

shattered live clav

Image showing fracture in the clavicle and bone growth in the scapula and pelvis (Fig. 6 p. 77). Image taken from Wheeler et al. (2013) article.

It is not enough to use the fractures present to determine a case of child abuse, and the authors used isotopic analysis to investigate the child’s diet. It was found that there was a depletion in nitrogen and carbon, and it is suggested that this may have been caused by a reduced consumption of protein rich foods. In addition to this a comparison of Burial 519’s pathologies to other the juveniles to shed light on the causation. The overall trauma rate of the excavated individuals was 5.7% in individuals aged 0 -15 years. There was only one other juvenile who had multiple fractures and it was found that these all occurred in one single event (Wheeler 2009) and related to an accidental event; such as a fall or high-verlocity impact. This makes the skeleton in Burial  519 unique. 

By taking a comparative and holistic approach the authors suggest that the majority of the fractures seen in Burial 519 are a result of non-accidental trauma and could be classified as child abuse. It is suggested that this behaviour is not usual for the society as few traumas were present in other juvenile skeletons. This skeleton may be the oldest case of non-accidental trauma in the archaeological record; although it is unlikely that it will be the oldest on. Other examples may have been looked over due to poor preservation or excavation. 

Article Reference:

Wheeler, S. M., L. Williams, et al. (2013). “Shattered lives and broken childhoods: Evidence of physical child abuse in ancient Egypt.” International Journal of Paleopathology 3(2): 71-82.

An Example of Osteogenesis Imperfecta in the Archaeological Record

Skeleton B532 witj possible OI. Image taken from Cope & Dupras artile, fig. 4 p.196

Skeleton B532 with possible OI. Image taken from Cope & Dupras article, fig. 4 p.196

Osteogenesis Imperfecta (OI), more commonly known as ‘brittle bone’ disease is a condition which causes bones to be fragile and break easily. I have a personal interest in this condition and therefore wondered if there was any evidence of the condition in the archaeological record. A quick search produced this article ‘Osteogenesis Imperfecta in the Archaeological Record: An Example from the Dakhleh Oasis, Egypt,’ by Cope & Dupras (2011).

OI results from a genetic mutation that affects the production of collagen in the body. Collagen, along with calcium, provides strength and flexibility in bones with collagen providing flexibility. When this is removed bones become brittle and therefore will fracture easily. You can see this for yourself by baking a bone, as this removes the collagen, follow this link if you want to try if yourself. In the case of OI a genetic mutation diminishes the production of collagen resulting in multiple fractures and breaks. The majority of individuals with the condition receive it through a dominant mutation, whilst a small portion have an autosomal recessive condition. There are seven categories of OI with type I being the mildest form. I will summarise the different types below but there is also a more extensive table describing the categories on page 189 of the article.

  • Type I: mildest, high risk of fractures, subsides at puberty, individual reaches normal height.
  • Type II: typicallystill born due to a  respiratory complications
  • Type III: likely to die shortly after birth as a result of respirority faliure.
  • Type IV: short stature (smaller than type I), bone fragility not identified at birth. Progressive bowing of bones.
  • Type V: similar to type IV but possible calcification of interosseous membranes of forearms and hyperplastic calluses of bone.
  • Type VI and VII: Rare. Scale-like structure to lamella with type VI having an increase in osteoid thickness and VII with a shortening of femora and humeri.

The article ‘Osteogenesis Imperfecta in the Archaeological Record: An Example from the Dakhleh Oasis, Egypt’ proposes that a fetal skeleton, B532 excavated in a cemetery in Egypt, may have OI. The cemetery dates from the Ptolemaic to the Romano-Byzantine period and the grave itself was found in unusual position. Typical juvenile burials of this at this site were orientated East-West in a supine, extended position (how we usually think of a body when it is buried). However, this individual was recovered close to the surface lying partially on it’s back and right side in a semi-flexed position. The skeleton was in excellent condition due to the arid environment resulting in exceptional preservation and was given an estimate age of 36 – 42 weeks.

Typical infant burial at cemetrey (left) and atypical burial of B532 (right). Image taken from Cope & Dupras article, fig. 3 p.192.

Typical infant burial at cemetrey (left) and atypical burial of B532 (right). Image taken from Cope & Dupras article, fig. 3 p.192.

A full pathological assessment of B532 was completed with a summary provided in table 2, p. 194 of the article. The most prominent pathology of this individual was the severe curvature of the long bones and barrel-shaped rib cage. This barrel-shape is a result in abnormal curvature and thinness of the ribs. The curve in the long bones was predominately anterolateral (to the front and to the side) with the femora having the most extensive. In addition to the curves visible in the long bones the left femur, tibia and ulna also had fractures. These were complete in the ulna and tibia and partial in the femur.

The cortical bone was also had an unusual appearance which was coarse and patchy. This was observed in the left humerus and the right ulna and radius. The medullary cavity of these bones, plus the other humerus, was also narrowed. Both of these features are unusual and indicate a problem in the development of the bone. Microscopic analysis of type II OI has found that due to a disorganised osteoid and calcified bone matrix patchy bone mineralization can occur. In addition to this when using a light and electron microscope to examine type II OI sample an absence of mineralization at the distal ends of the growth plates was observed; instead starting further down the diaphysis. This lack of mineralization may account for the uneven surface seen in B532, and when combined with the observed fractures and curvature of the long bones indicates a possible diagnosis of OI, type II/III or IV.

Perimortem incomplete fracturing of the left femur of B532, with radiograph of same bone on the right. Image taken from Cope & Dupras article, fig. 6 p.196.

Perimortem incomplete fracturing of the left femur of B532, with radiograph of same bone on the right. Image taken from Cope & Dupras article, fig. 6 p.196.

In all pathological cases a differential diagnosis is also given for comparison. In this individual many diagnoses were given which may also account for the bowing seen in B532. A full list is given in table 3, p.196 and includes Campomelic Dysplasia 1, a condition which results in bowing of the long bones and hypoplastic fibulae and scapulars caused by abnormal skeletal development during the prenatal period.

This was a very interesting case study of a fetal skeleton who possibly suffered with the condition Osteogenesis Imperfecta. The article is a good example of a through approach to diagnosing pathology in an excavated skeleton. This is not the only example of OI in the archaeological record and I intend to go away and find out more about the other cases. 

Reference:

Cope, D. & Dupras, T. (2011).’ Osteogenesis Imperfecta in the Archaeological Record: An Example from the Dakhleh Oasis, Egypt,’ by Cope & Dupras’ in International Journal of Paleopathology 1: 188-199. ISSN 1879-9817, http://dx.doi.org/10.1016/j.ijpp.2012.02.001. (http://www.sciencedirect.com/science/article/pii/S1879981712000022)

 

My Trip to the Grant Museum, London

Lion Skeleton at the Grant Museum of Zoology

Lion Skeleton at the Grant Museum of Zoology

Today I had an interview in London and as it was in the morning I thought why not visit a museum on my way home?! I was already coming back on the Northern Line and knew that it went through Euston, where the Grant Museum is located. I have wanted to visit this museum for a while but as it is slightly out of the centre, and the other touristy parts of London I hadn’t managed to make it there yet.

It’s a very cute museum with specimens held in wooden cases which span the wall of the museum. It is only one room, and for the amount of space they have the specimens are shown off very well. There are skeletons, skulls and wet specimens of all sorts of creatures spanning the animal kingdom and of all shapes and sizes. I don’t know if I had a particular favourite but it was pretty awesome that they had a complete skeleton of a dugong. I think one of the most incrediable skulls that i saw was of a domestic pig. It didn’t say the particular breed of pig but it was impressive none the less!

Dugong Skeleton at the Grant Museum of Zoology

Dugong Skeleton at the Grant Museum of Zoology

I took a few photos of some of the specimens which you can find on my tumblr page. I also took some photos of the Micrarium, a small alcove which presents hundreds of microscope slides of the smallest animals. They were wonderful to look at and reminds you of how intricate biology is and how beautiful creatues can be, even if we can barely see them.

I would recommend anyone who has an interest in biology and/or zoology to visit the museum. It’s quiter and smaller than the better known Natural History Museum but it’s just as wonderful!

Visit both my tumblr posts to see pictures of the Micraraium and other speimens in the musem. Hopefully some of them will be featuring in future Skull of the Months!

First Full Day Volunteering at the Royal College of Surgeons

Outside of the Royal College of Surgeons. Image taken rom http://nobelbiocare-eyearcourse.com/fgdp.html.

Outside of the Royal College of Surgeons. Image taken rom http://nobelbiocare-eyearcourse.com/fgdp.html.

I was really excited to start my first full day of volunteering yesterday – I don’t think I really slept that well! I was very much looking forward to working with human bones again, and to see the people I had met the week before. Overall I can say it was a very good day!

Both of us, there is another lady volunteering with me called Diana, started where we finished from last week. This was with three boxes full of assorted bones – oh and there was also one hat box containing a skull! All of the bones were jumbled up and we had no idea what was in those boxes so we started off by taking every bone out and grouping them in their elements, e.g. humerus’s together, feet together etc.

We then attempted to put together elements which looked like they came from the same individual. This is was predominately based on length, colour, and whether any elements seemed to articulate with another. We managed to group some elements together although it was quite difficult at times, for example if you didn’t have two of the same element (a left side and a right side) it was tricky to be sure whether different bones of the body went together. However, we tried our best and managed to identify about 4 partial skeletons and to be honest it was quite a lot of fun but difficult – like doing trying to identify many puzzles with only some of the pieces and all jumbled up! I haven’t had the chance to do this before so it was quite nice to put the theory and my knowledge into practice.

As well as just assorted bones there were quite a few skulls (including a dog skull!) – most of them with their skull caps removed. So like the other bones of the skeleton we had to piece together any loose skull caps or mandibles and I think by the end of if we had about 8 partial or complete skulls with a couple of skulls and jaws left over! 

One thing that is really interesting about this project is getting the chance to see how people in the past used bones for study. As many of the skeletons we are sorting through were teaching tools a lot have either pen markings, for the muscle attachments, or are wired together. It’s quite odd to see this as they have damaged the bones. The majority of these will be unusable as teaching tools for the current and future students due to this damage caused. I don’t have any issues with reconstructing the full skeleton – if it is done well and with suitable material (not as we saw in one vertebrae column wire which had completely destroyed many of the bodies of the individual vertebrae). These bones were also in living humans and therefore demand respect when being handled. I know attitudes were different in the past but it’s still hard to comprehend sometimes.

Overall I had a really good day at the College and am very much looking forward to going back and sorting some more bones next week!   

Secrets of Bones Episodes 4 and 5

So I’ve finally managed to catch up on the last couple of epiodes of Ben Garrod’s Secrets of Bones. These episodes first looked how the skeleton in vertebrates helped to sense the world whilst the second looks how it helps with hunting. As with the previous episdoes Ben Garrod takes us through a variety of animals and their skeletal adaptations which illustrate the beauty and plasticity of bones. 

Episode 4, entitled ‘Sensing the World’, and looked at the eyes and the ability to hear and smell and how the bones assist with this. An example of how the skull has adapted to assist with imporving sight can be seen in the tarsier. This primate has giant eyes and orbits to match in order to locate and catch insects. They are noctural animals and have evolved to have large eyes in oder to take in as much light as possible. I remember looking at these amazing skulls during my second year at university. The aim of the class was to examine, study and learn the different characteristics of the primare skulls and the tarsier’s is one I will never forget!

Towards the end of the episode the focus shifted to the ability to smell and I was happy to see that one of my skulls of the month made it to the list! This was the polar bear which has a bony structure in the nasal bones called the turbinates. This area warms up the area whilst the other areas are covered with hundreds of sensory cells. In addition to the polar bear another one of skulls of the month about the sperm whale also featured in the programme. This whale has a grooved channel in it’s lower jaw which transfers returning echos which the whale puts out to build up a picture of it’s surrounding. This is an incrediable animal made even more awesome with it’s ability to echolocate.

Moving on from the whale’s jaw episode 5 looks at the skeletal adaptations to assist in an animals ability to get food. Of course when you think of incrediable jaws in the animal kingdom you have to think of the snake. I always thought that a snake dislocated it’s jaw to consue it’s prey but that’s not the case – the lower jaw is not one complete bone but two which is sttached by strong, flexiable ligaments. It is these ligaments which allow the snake’s jaw to stretch. It was pretty awesome yet distusting to watch!

The middle part of the epsiode was about teeth and how they vary between differnet animals. At first we saw an elephants molar and learnt that they have six sets of teeth through out their lifetime; which is pretty cool! We were also shown the spealised teeth of the crab eating seal which uses them as a filter. I think I was actually shown a jaw of this seal on my first visit to the Natural History Museum’s stores quite a few months back. They were really impressive but really unusal!

The final part looked at how primates have evolved to have an opposable thumb. There was a particular focus on the human hands, but I will come back to that in a later post. However another primate, the Ayi-Ayi a lemur, was also shown. This is because of their incrediable middle finger which is elongated and thin. This is used as a tool to tap on trees to try and locate grubs. It does this by ecolocation, the only primate to d oso, and once a grub has been found it breaks into the tree and uses it’s finger again to drag the grub out. I have always found this animal intriguing; it looks unusal but has amazing adaptations. 

Once again Ben Garrod presents the episodes with ease and I throughology enjoyed them. Next weeks episode look at the skeleton and how it aids with getting a mate – I’m very much looking forward to it!

 

How the Dead Could Help Cure the Future

Anthropologists in Italy have been excavating an abandoned medieval church and have uncovered skeletons which date from the Medieval period running through to the mid-1800s. From these skeletons the DNA is going to be extracted from their teeth and analysis carried out on soil from their stomach area. Why do this? The researchers are hoping to gain more knowledge into the bacteria which caused the Black Death as a very similar strain of the bacteria, Yersinia pestis, still exists in some small rodents in parts of the world today. They want to know why the bacteria moved from rodent to humans and what made the plague spread so quickly in the 14oos.

In another grave, dating to a later period, a mass grave was discovered where the individuals looked to have been buried in a rush. One skeleton in particular was of interest to the researchers as she was the perfect specimen as nearly every bone was in-tact. Again the researchers want to know what killed so many people and why they were buried so hastily. Currently the hypothesis is cholera and now they want to trace the evolution of the disease. 

By conducting research into the dead’s DNA modern medicine may be improved and new vaccines or medicines may be created. This is the reason why we must conduct research on our dead – they are amazing and insightful specimens which may help the future human population.

Go to the official ‘The Thousand-Year Graveyard’ site here: http://spark.sciencemag.org/the-thousand-year-graveyard