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Skeletal Series: The Basic Human Osteology Glossary

19 Dec

Introducing the Human Osteology Glossary

It is important for the budding human osteology student that they understand and correctly apply the basic terms used in the discipline to help identify and describe the skeletal anatomy under study.  Since human osteologists study the skeletal remains of anatomically modern humans (Homo sapiens) the terminology used, specifically the anatomical terminology, has to be precise and correct as befitting the medical use of such terms.

Human osteology remains the foundation on which the disciplines of forensic anthropology and bioarchaeology are built upon, although it is noted that the disciplines can be misleading across international divides.  For example, in the United Kingdom bioarchaeology is still used to refer to the study of both human and non-human skeleton remains from archaeological sites, whilst bioarchaeology in the United States normally refers to human remains only.  It should also be noted here that the other related disciplines, such as palaeoanthropology and biological anthropology, study not just the modern human skeleton but also the skeletal and fossilized remains of extant (genera such as Pan, Pongo and Gorilla) and extinct hominins.  Nevertheless the terminology remains the same when describing the skeletal anatomy of both human and non-human individuals.

Glossary Arrangement

This short glossary is intended to provide a basic introduction to the terminology used in the disciplines that utilizes human osteology as a core focus for the research undertaken.  The terminology documented here also includes a brief description of the word and, where possible, an example of its use.  Primarily the glossary acts as a reference post in order to be used in conjunction with the Skeletal Series posts on this site, which help outline and introduce each skeletal element of the human body section by section and as appropriate.  However please note that the glossary is also arranged in a manner in which it befits the student who needs to quickly scan the list in order to find a specific and relevant word.

Therefore the glossary is arranged in a thematic presentation as follows:

1. Discipline Definitions
2. The Human Body:
– a) Macro
– b) Micro
– c) Growth
– d) Disease and Trauma
3. Anatomical Foundations:
– a) Anatomical Planes of Reference
– b) Directional Terminology
– c) Movement Terminology
4. Postmortem Skeletal Change
– a) Postmortem Skeletal Change

The glossary ends with an introduction to the terminology used to describe the postmortem aspects of body deposition.  This is because it is an important aspect and consideration of any skeletal analysis undertaken.  The terminology used in this section leads away from the strictly anatomical terminology of the sections above it and introduces some terms that are used in archaeology and associated disciplines.

Reference Note

Please note that the bibliography provided indicates a number of important texts from which this glossary was compiled.  The key text books highlighted also introduce the study of the human skeleton, from a number of different perspectives, including the gross anatomical, bioarchaeological and human evolutionary perspectives.  Find a copy of the books at your library or order a copy and become engrossed in the beauty of the bones and the evidence of life histories that they can hold.

The Glossary:

1) – Discipline Definitions

Bioanthropology:  A scientific discipline concerned with the biological and behavioral aspects of human beings, their related non-human primates, such as gorillas and chimpanzees, and their extinct hominin ancestors.  (Related Physical Anthropology).

Bioarchaeology:  The study of human and non-human skeletal remains from archaeological sites.  In the United States of America this term is used solely for the study of human skeletal remains from archaeological sites.

Forensic Anthropology:  An applied anthropological approach dealing with human remains in legal contexts.  Forensic anthropologists often work with coroners and others, such as disaster victim identification teams, in analysing and identifying human remains (both soft and hard tissues) from a variety of contexts including but not limited ID’ing remains from natural disasters, police contexts, war zones, genocides, human rights violations, etc.

Human Osteology:  The study of human skeletal material.  Focuses on the scientific interpretation of skeletal remains from archaeological sites, including the study of the skeletal anatomy, bone physiology, and the growth and development of the skeleton itself.   

Palaeoanthropology:  The interdisciplinary study of earlier hominins.  This includes the study of their chronology, physical structure and skeletal anatomy, archaeological remains, geographic spans, etc. (Jurmain et al. 2011).

Physical Anthropology:  Concerned with the biological skeletal remains of both humans and extant and extinct hominins, anatomy, and evidence of behaviour.  The discipline is often considered congruent with the term bioanthropology, or biological anthropology.  (Related Bioanthropology).

2) a. – The Human Body: Macro

Appendicular Skeleton:  The skeletal bones of the limbs.  Includes the shoulder and pelvic girdles, however it does not include the sacrum.  Skeleton SK423 largely consisted of the non-fragmented disarticulated appendicular elements.

Axial Skeleton:  The skeletal elements of the trunk of the body.  Includes the ribs, vertebrae and sternum.  The body of SK424 was particularly fragmented in-situ, with little sign of excavation or post-excavation damage evidenced on the axial skeleton suggesting fragmentation post-burial.

Cortical (Compact) Bone:  The solid and dense bone found in the bone shafts and on the external surfaces of bone itself.  The cortical bone of the mid-shaft of the right humerus of the tennis player displayed increased thickening.  This is, in this individuals case whose physical history is known, due to the predominance of the right arm during intense and long-term use in physical exercise (see Wolff’s Law). 

Dentin (Dentine):  Calcified but slightly resilient dental connective tissue.  In human growth primary dentin appears during growth whereas secondary dentin forms after the root formation of the tooth is complete (White & Folkens 2005: 421).

Diaphysis:  The shaft portion of a long bone.  The diaphysis of the femur is one of the longest shafts found in the human skeleton, as the femur is the longest bone.

Dry Bone:  Refers to archaeological bone where no soft, or wet, tissue survives, hence the bone is dry.  It should be noted that, when subject to x-rays for investigation, archaeological dry bone radiological images are improved due to a lack of soft tissues obscuring the bone condition.

Elements (Skeletal):  Used to refer to each individual bone.  The human adult body has, on average, 206 individual skeletal elements.

Enamel:  Enamel is an extremely hard brittle material which covers the crown of a tooth.

Endosteum:  A largely cellular membrane that lines the inner surface of bones which is ill-defined (White & Folkens 2005: 421).

Epiphysis:  The epiphysis refers to the often proximal and distal ‘caps’ of long bones that develop from a secondary ossification centre.  The epiphysis of the long bones can, when used in conjunction with other skeletal markers of aging, particularly dentition, provide a highly accurate  age-at-death in non-adult human skeletal remains.

Medullary Cavity:  The cavity found inside the shaft of a long bone.  The medullary cavity of the femur is the site of the longest medullary cavity found in the human body.  The medullary cavity is the location where red and yellow bone marrow is stored and where the red and white blood cells are produced. 

Metaphyses:  The metaphyses refer to the expanded and flared ends of the shaft (or diaphysis) of long bones.  Both the femoral and humeral diaphyses display flared distal metaphyses which are indicative of their anatomical positioning.

Morphology:  The form and structure of an object.  The morphology of the femora is dictated by a variety of factors, not least the size, age, sex and weight of the individual.

Musculoskeletal System:  The musculoskeletal system provides the bony framework of the body in which the muscles attach onto and are able to leverage bones to induce movement.  The musculoskeletal system is responsible for a number of core bodily functions, including blood production and nourishment, alongside providing a stable and safe environment for vital organs.

Osteology:  The scientific study of bone.  Bones form the basis of the skeletal system of vertebrate animals, including humans.  In the United States of America bioarchaeology refers to the study of human bones within an archaeological context.

Periosteum:  The thin dense vascular connective tissue that covers the outer surfaces of bone during life, except on areas of articulation.  The periosteum tissue plays an important part in the maintenance of healthy bone, helping to also provide the body with blood via the bone marrow and associated vessels.  The periosteum provides an important area of osteogensis following a bone fracture.

Postcranial Skeleton:  All bones but the mandible and cranium.  The postcranial skeleton of SK543 was exceptionally well-preserved within the grave context but due to grave cutting the cranium and mandible were completely disturbed and not present within the context recorded.

Trabecular (Spongy) Bone:  Refers to the honeycomb like structure of bone found within the cavity of bones themselves.

2) b. – The Human Body: Micro

Cartilage:  Cartilage is a flexible connective tissue which consists of cells embedded in a matrix.  In the human skeletal system cartilage is found between joints, such as the knee and in forms such as the intervertebral disk in the spine and in the ribcage.  There are three types of cartilage: hyaline, fibrocartilage and elastic cartilage in the human skeletal system, although 28 different types of cartilage have now been identified in the human body as a whole (Gosling et al. 2008:9).

Collagen:  Collagen is a fibrous structural tissue in the skeleton which constitutes up to 90% of bone’s organic content (White & Folkens 2005: 42).

Haversian Canal (Secondary Osteons):  Microscopic canals found in compact, or cortical, bone that contain blood, nerve and lymph vessels, alongside marrow.

Hydroxyapatite:  A dense, inorganic, mineral matrix which helps form the second component of bone.  Together with collagen hydroxyapatite gives bone the unique ability to withstand and respond to physical stresses.

Lamellar (Mature) Bone:  Bone in which the ‘microscopic structure is characterized by collagen fibres arranged in layers or sheets around Haversian canals’ (White & Folkens 2005: 423).  Lamellar bone is mechanically strong.  Related woven (immature) bone.

Osteoblast:  Osteoblasts are the ‘bone-forming cells which are responsible for synthesizing and depositing bone material’ (White & Folkens 2005: 424).

Osteoclast:  Osteoclasts are the cells responsible for the resorption of bone tissue.

Osteocyte:  Osteocytes are the living bone cell which is developed from an osteoblast (White & Folkens 2005: 424).

Osteon:  The osteon is a Haversian system, ‘a structural unit of compact bone composed of a central vascular (Haversian) canal and the concentric lamellae surrounding it; a Primary Osteon is composed of a vascular canal without a cement line, whereas the cement line and lamellar bone organized around the central canal characterize a Secondary Osteon‘ (White & Folkens 2005: 424).

Remodeling:  Remodeling is the cyclical process of bone resorption and bone deposition at one site.  The human skeleton continually remodels itself throughout life, and after full growth has been achieved towards the end of puberty.  Further to this bone is a tissue that responds to physical stress and remodels as appropriate. 

Woven (Immature) Bone:  characterized by the haphazard organisation of collagen fibres.  Primarily laid down following a fracture and later replaced by lamellar bone.  Woven bone is mechanically weak.  Related lamellar (mature) bone.

2) c. – The Human Body: Growth

Appositional Growth:  The process by which old bone that lines the medullary cavity is reabsorbed and new bone tissue is grown beneath the periosteum, which increases the bone diameter.

Endochondral Ossification:  One of two main processes of bone development in which cartilage precursors (called cartilage models) are gradually replaced by bone tissue (White & Folkens 2005: 421).

Epiphyseal (Growth) Plate:  The hyaline cartilage plate found at the metaphyses of the long bones during growth of the individual (i.e. non-adults), where bone growth is focused until full growth cycle has been completed.

Idiosyncratic:  Referring to the individual.  The normal morphology of the human skeleton, and its individual elements, is influenced by three main factors of variation: biological sex (sexual dimorphism), ontogenetic (age), and idiosyncratic (individual) factors.

Intramembranous Ossification:  One of two main processes of ‘bone development in which bones ossify by apposition on tissue within an embryonic connective tissue membrane’ (White & Folkens 2005: 422).

Ontogeny:  The growth, or development, of an individual.  Ontogeny can be a major factor in the morphological presentation of the human skeleton.

Osteogenesis:  The formation and development of bone.  Embryologically the development of bone ossification occurs during two main processes: intramembranous and endochondral ossification.

Wolff’s Law:  Theory developed by German anatomist and surgeon Julius Wolff (1836-1902) which stated that human and non-human bone responded to the loads, or stresses, under to which it is placed and remodels appropriately within a healthy individual.

Sexual Dimorphism:  The differences between males and females.  The human skeleton has, compared to some animal species, discrete differences in sexual dimorphism; however there are distinct functional differences in the morphology of certain elements which can be used to determine biological sex of the individual post-puberty.

2) d. – The Human Body: Disease and Trauma

Atrophy:  The wastage of an organ or body tissue due to non-use.  Atrophy can be an outcome of disease processes in which the nerves are damaged, leading to the extended, or permanent, non-use of a limb which can lead to muscle wastage and bone resorption.

Blastic Lesion: Expansive bone lesion in which bone is abnormally expanded upon as part of part of a disease process.  The opposite of lytic lesion.

Calculus: Tartar; a deposit of calcified dental plaque on the surface of teeth.  The calculus found on the teeth of the archaeological skeleton can contain a wealth of information on the diet and extramasticatory activities of the individual.

Callus:  The hard tissue which is formed in the osteogenic (bone cell producing) layer of the periosteum as a fracture repair tissue.  This tissue is normally replaced by woven bone, which is in turn replaced by lamellar (or mature) bone as the bone continues to remodel during the healing process.

Caries:  Caries are ‘a disease characterized by the ‘progressive decalcification of enamel or dentine; the hole or cavity left by such decay’ (White & Folkens 2005: 420).  The extensive caries present on the 2nd right mandibular molar of Sk344 nearly obliterates the occlusal (chewing) surface of the tooth.

Compound Fracture:  A fracture in which the broken ends of the bone perforate the skin.  A compound fracture can be more damaging psychologically to the individual, due to the sight of the fracture itself and soft tissue damage to the skin and muscle.  Compound fractures also lead to an increased risk of fat embolism (or clots) entering the circulatory system via marrow leakage, which can be potentially fatal.

Dysplasia:  The abnormal development of bone tissue.  The bone lesions of fibrous dysplasia display as opaque and translucent patches compared to normal healthy bone on X-ray radiographic images.

Eburnation: Presents as polished bone on surface joints where subchondral bone has been exposed and worn.  Osteoarthritis often presents at the hip and knee joints where eburnation is present on the proximal femoral head and distal femoral condyle surfaces, alongside the adjacent tibia and iliac joint surfaces.

Hyperostosis:  An abnormal growth of the bone tissue.  Paget’s disease of bone is partly characterized by the hyperostosis of the cranial plates, with particularly dense parietal and frontal bones.

Hyperplasia:  An excessive growth of bone, or other, tissues.

Hypertrothy:  An increase in the volume of a tissue or organ.

Hypoplasia:  An insufficient growth of bone or other tissue.  Harris lines are dense transverse lines found in the shafts of long bones, which are indicative of arrested growth periods, as non-specific stress events, in the life of the individual.  Harris lines can often only be identified via X-ray radiography or through visual inspection of internal bone structure.

Lytic Lesion:  Destructive bone lesion as part of a disease process.  The opposite of a blastic lesion.  Syphilitic lytic bone lesions often pit and scar the frontal, parietal and associated facial bones of the skull.

Osteoarthritis:  Osteoarthritis is the most common form of arthritis, which is characterized by the destruction of the articular cartilage in a joint.  This often leads to eburnation on the bone surface.  Bony lipping and spur formation often also occur adjacent to the joint.  This is also commonly called Degenerative Joint Disease (DJD) (White & Folkens 2005: 424).

Osteophytes:  Typically small abnormal outgrowths of bone which are found at the articular surface of the bone as a feature of osteoarthritis.  Extensive osteophytic lipping was noted on the anterior portion of the vertebrae bodies of T2-L3 which, along with the evidence of eburnation, bony lipping and spurs presenting bilaterally on the femora and tibiae, present as evidence of osteoarthritis in SK469.

Pathognomonic:  A pathological feature that is characteristic for a particular disease as it is a marked intensification for a diagnostic sign or symptom.  A sequestrum (a piece of dead bone that has become separated from normal, or healthy, bone during necrosis) is normally considered a pathgonomic sign of osteomyelitis. 

Pathological Fracture:  A bone fracture that occurs due to the result of bones already being weakened by other pathological or metabolic conditions, such as osteoporosis (White & Folkens 2005: 424).

Palaeopathology:  The study of ancient disease and trauma processes in human skeletal (or mummified) remains from archaeological sites.  Includes the diagnosis of disease, where possible.  A palaeopathological analysis of the skeletal remains of individuals from the archaeological record is an important aspect of recording and contextualising health in the past.

Periodontitis:  Inflammation around the tissues of a tooth, which can involve the hard tissues of the mandibular and maxilla bone or the soft tissues themselves.  Extensive evidence of periodontitis on both the mandible and maxilla suggests a high level of chronic infection.

Periostitis: The inflammation of the periosteum which is caused by either trauma or infection, this can be either acute or chronic.  The anterior proximal third of the right tibia displayed extensive periostitis suggesting an a persistent, or long term, incidence of infection.

Radiograph:  Image produced on photographic film when exposed to x-rays passing through an object (White & Folkens 2005: 425).  The radiographic image of the femora produced evidence of Harris lines which were not visible on the visual inspection of the bones.

3) a. – Anatomical Planes of Reference

Anatomical Position (Standard):  This is defined as ‘standing with the feet together and pointing forward, looking forward, with none of the leg bones crossed from a viewer’s perspective and palms facing forward’ (White & Folkens 2005: 426).  The standard anatomical position is used when referring to the planes of reference, and for orientation and laying out of the skeletal remains of an individual for osteological examination, inventory, and/or analysis.

Coronal (frontal/Median):  The coronal plane is a vertical plane that divides the body into an equal forward and backward (or anterior and posterior) section.  The coronal plane is used along with the sagittal and transverse planes in order to describe the location of the body parts in relation to one another.

Frankfurt Horizontal:  A plane used to systematically view the skull which is defined by three osteometric points:  the right and left porion points (near the ear canal, or exterior auditory meatus) and left orbitale.

Oblique Plane:  A plane that is not parallel to the coronal, sagittal or transverse planes.  The fracture to the mid shaft of the left tibia and fibula was not a transverse or spiral break, it is an oblique fracture as evidenced by the angle of the break. 

Sagittal:  A vertical plane that divides the body into symmetrical right and left halves.

Transverse:  Situated or extending across a horizontal plane.  A transverse fracture was noted on the midshaft of the right femur.  The fracture was indicative of a great force having caused it, likely in a traumatic incident.

3) b. – Anatomical Directional Terminology

Superior:  Superior refers towards the head end of the human body, with the most superior point of the human body the parietal bone at the sagittal suture (White & Folkens 2005: 68).

Inferior:  Inferior refers towards the foot, or the heel, which is the calcaneus bone.  Generally this is towards the ground.  The tibia is inferior to the femur.

Anterior:  Towards the front of the body.  The sternum is anterior to the vertebral column.

Posterior:  Towards the back of the body.  The occipital bone is posterior to the frontal bone of the cranium.

Proximal:  Near the axial skeletonThe term is normally used for the limb bones, where for instance the proximal end of the femur is towards the os coxa.

Medial:  Towards the midline of the body.  The right side of the tongue is medial to the right side of the mandible.

Lateral:  The opposite of medial, away from the midline of the body.  In the standard anatomical position the left radius is lateral to the left ulna.

Distal:  furthest away from the axial skeleton; away from the body.  The distal aspect of the humerus articulates with the proximal head of the radius and the trochlear notch of the ulna.

Internal:  Inside.  The internal surface of the frontal bone has the frontal crest, which is located in the sagittal plane.

External: Outside.  The cranial vault is the external surface of the brain.

Endocranial:  The inner surface of the cranial vault.  The brain fills the endocranial cavity where it sits within a sack.

Ectocranial:  The outer surface of the cranial vault.  The frontal bosses (or eminences) are located on the ectocranial surface of the frontal bone.

Superficial:  Close to the surface of the body, i.e. towards the skin.  The bones of the cranium are superficial to the brain.

Deep:  Opposite of superficial, i.e. deep inside the body and far from the surface.  The lungs are deep to the ribs, but the heart is deep to the lungs.

Palmar:  Palm side of the hand.  The palm side of the hand is where the fingers bear fingerprints.

Plantar:  The plantar side of the foot is the sole.  The plantar side of the foot is in contact with the ground during normal ambulation.

Dorsal:  Either the top of the foot or the back of the hand.  The ‘dorsal surface often bears hair whilst the palmar or plantar surfaces do not’ (White & Folkens 2005: 69).

3) c. – Anatomical Movement Terminology

Abduction:  Abduction is a laterally directed movement in the coronal plane away from the sagittal, or median, plane.  It is the opposite of adduction.  Standing straight, with the palm of the left hand anterior, raise the left arm sideways until it is horizontal with the shoulder: this is the action of abducting the left arm.

Adduction:  Adduction is the medially directed movement in the coronal plane towards the sagittal, or median, plane.  It is the opposite of abductionStanding straight, with the palm of the right hand anterior, and the right arm raised sideways until it is horizontal with the shoulder, move the arm down towards the body.  This is adduction.

Circumduction:  Circumduction is a ‘circular movement created by the sequential combination of abduction, flexion, adduction, and extension’ (Schwartz 2007: 373).  The guitarist who performs the action of windmilling during playing is circumducting their plectrum holding limb.

Extension:  Extension is a movement in the sagittal plane around a transverse axis that separates two structures.  It is the opposite of flexionThe extension of the forearm involves movement at the elbow joint.

Flexion:  A bending movement in the saggital plane and around a transverse axis that draws two structures toward each other (Schwartz 2007: 374).  It is the opposite of extensionThe flexion of the forearm involves movement at the elbow joint.

Lateral Rotation:  The movement of a structure around its longitudinal axis which causes the anterior surface to face laterally.  It is the opposite of medial rotation.

Medial Rotation:  The movement of a structure around its longitudinal axis that causes the anterior surface to face medially.  It is the opposite of lateral rotation (Schwartz 2007: 376).

Opposition: The movement of the ‘thumb across the palm such that its “pad” contracts the “pad” of another digit; this movement involves abduction with flexion and medial rotation’ (Schwartz 2007: 377).

4) a. – Postmortem Skeletal Change

Antemortem:  Before the time of death.  The evidence for the active bone healing on both the distal radius and ulna diaphyses, with a clean fracture indicating use of a bladed instrumented, suggests that amputation of the right hand occurred antemortem. 

Bioturbation:  The reworking of soils and associated sediments by non-human agents, such as plants and animals.  Bioturbation can lead to the displacement of archaeological artefacts and structural features and displace deposited human skeletal bone.  Evidence of bioturbation in the cemetery was noted, as irregular tunnels were located across a number of different grave contexts suggesting the action of a burrowing or nesting mammal.  This led to the disarticulation of skeletal material within the grave contexts themselves which, on first investigation, may have led to an incorrect analysis of the sequence of events following the primary deposition of the body within the grave.

Commingled:  An assemblage of bone containing the remains of multiple individuals, which are often incomplete and heavily fragmented.  The commingled mass grave found at the Neolithic site of Talheim, in modern southern Germany, suggest that, along with the noted traumatic injuries prevalent on the individuals analysed, rapid and careless burial in a so-called ‘death pit’ took place by the individuals who carried out the massacre.  The site is a famous Linearbandkeramik (LBK) location which dates to around 5000 BC, or the Early European Neolithic.  Similar period mass burials include those at Herxheim, also in Germany, and Schletz-Asparn in nearby Austria.

Diagenesis:  The chemical, physical, and biological changes undergone by a bone through time.  This is a particularly important area of study as the conservation of bones must deal with bacteria and fungal infection of conserved bone if the skeletal material is to be preserved properly.  Analysis of the diagenesis of skeletal material can also inform the bioarchaeologist of the peri and postmortem burial conditions of the individual by comparing the environmental contexts that the bone had been introduced to.

Perimortem: At, or around, the time of death.  The decapitation of SK246 occurred perimortem as evidenced by the sharp bladed unhealed trauma to the associated body,  pedicles, lamina and spinal arches of the C3 and C4 vertebrae.

Postmortem: Refers to the period after the death of the individual.  It is likely that the body had been moved postmortem as indicated by position of the body in the bedroom and by the extensive markers on the skin, suggesting physical manipulation and accidental contusions.  Further to this the pooling of the blood within the first few hours postmortem was not indicative of where the body was located at the time of discovery.

Postmortem Modification:  Modifications, or alterations, that occur to the skeletal remains after the death of the individual.  No postmortem modification of the skeletal elements of SK543 was noted, however extensive evidence of bioturbation in the form of root action was noted on across the majority (> 80%) of the surface of the surviving skeletal elements recovered.

Taphonomy:  The study of processes that can affect the skeletal remains between the death of the individual and the curation, or analysis, of the individual.  There are a variety of natural and non-natural taphonomic processes that must be considered in the analysing of human skeletal material from archaeological, modern and forensic contexts.  This can include natural disturbances, such as bioturbation, or non-natural, such as purposeful secondary internment of the body or skeletal remains.

Note on the Terminology Used & Feedback

The terminology used above, and their definitions, are taken in part from the below sources.  Direct quotations are referenced to the source and page.  They, the sources in the bibliography, are a small handful of some of the exceptional books available which help to introduce the human skeletal system and the importance of being able to identify, study and analyse the bones in a scientific manner.  The human skeletal glossary present here is subject to revision, amendments and updates, so please do check back to see what has been included.  Finally, I heartily advise readers to leave a comment if revisions, or clarifications, are needed on any of the terms or definitions used in the glossary.

Bibliography & Further Reading

Gosling, J. A., Harris, P. F., Humpherson, J. R., Whitmore, I., Willan, P. L. T., Bentley, A. L., Davies, J. T. & Hargreaves, J. L. 2008. Human Anatomy: Colour Atlas and Texbook (5th Edition). London: Mosby Elsevier.

Jurmain, R., Kilgrore, L. & Trevathan, W. 2011. Essentials of Physical Anthropology. Belmont: Wadsworth.

Larsen, C. S. 1997. Bioarchaeology: Interpreting Behaviour from the Human Skeleton. Cambridge: Cambridge University Press.

Lewis, M. E. 2007. The Bioarchaeology of Children: Perspectives from Biological and Forensic Anthropology. Cambridge: Cambridge University Press.

Roberts, C. & Manchester, K. 2010. The Archaeology of Disease (3rd Edition). Stroud: The History Press.

Schwartz, J. H. 2007. Skeleton Keys: An Introduction Human Skeletal Morphology, Development, and Analysis (2nd Edition). New York: Oxford University Press.

White, T. D. & Folkens, P. A. 2005. The Human Bone Manual. London: Elsevier Academic Press.

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A Right To Bear Arms: A Traumatically Introduced Ursus Phalanx

31 May

Whilst browsing a recent edition of the International Journal of Palaeopathology I came across this article by Richards et al. (2013) titled ‘Bear Phalanx Traumatically Introduced Into A Living Human: Prehistoric Evidence‘; it is an eye-catching title I am sure you will agree!  Although it is common for skeletal remains to display traumatically introduced pathologies (see Roberts & Manchester 2010 and Waldron 2009), it is rare for palaeopathological case studies to document traumatically inserted foreign objects into a human skeleton, much less so to find a bear claw crushed into a human arm.  Yet this is exactly the case that Richards et al. (2013) document in a female skeleton dating from a Middle Period (500BC-300AD) Prehistoric Californian shellmound site called Ellis Island.

The individual, PHMA 12-2387, was found during archaeological excavations conducted in1906-1907 of the shellmounds that formerly lined the San Francisco Bay area, and the excavation recovered a total of 160 burials from the highly stratified shellmound middens (Richards et al. 2013: 48).  The shellmounds along the San Francisco Bay were inhabited by hunter-gatherers during the Middle Period, who focused their efforts on the near shore marine rich resources.  Interestingly the habitation period of the area at and around Ellis Island reflects occupation, abandonment and re-occupation over a 2000 year long span.  Following the osteological analysis of the nearly complete skeletal remains of PHMA 12-2387, it was concluded that the skeleton likely represented an adult female (biological sex based on pelvic features) aged between 30-40 years old (based on dental eruption and wear stage, epiphyseal and sutural closure, pubic symphysis and joint  surface morphology) at the time of death, who was buried supine with both her upper and lower limbs flexed (Richards et al. 2013: 49).

Now here is the interesting part.  Following the qualitative analysis of the normal ranges of joint and bone surface morphology of other shellmound individuals (N=159) and the comparison of the careful analysis of CT scans taken of the arms of PHMA 12-2387, it was concluded that the upper limbs bones of PHMA 12-2387 were large and strongly muscled, which were representative of a middle aged female who had suffered ‘traumatic injury that involved the left cubital fossa region, both forearms, and the right shoulder girdle’ (Richards et al. 2013: 50).  The right upper limb displays a bending fracture in the mid shaft of the ulna, which was complicated by the non-union of the break during the healing process.  Found within the left humerus cubital fossa was a Ursus (bear) phalanx, which had been driven in by a likely crushing trauma to a depth of 5 to 7mm into the dense cortex of the humeral shaft (See Figure 1).

Beartraumarichardsetal20133333

The CT scans of the upper limbs of PHMA 12-2387, where A represents varying views of both remaining limbs, and B shows the traumatically fractured right ulna and crushing injury of left cubital fossa of the humerus (See Richards et al. 2013: 50 for further information).

The injuries to this individual undoubtedly affected her movement.  The right upper limb would have suffered from problems with restricted range of the elbow joint, and restricted pronation and supination of the forearm due to the non-union fracture, whilst the trauma of the phalanx fractured through olecranon process and likely severed the m. triceps brachii, a major forearm extensor.  This likely resulted ‘in unopposed forearm flexion’, although pronation and supination of the forearm was ‘less affected’, with the bone material adapting to, and reflecting, the changes (Richards et al. 2013: 51).  The Ursus phalanx became fused within the injury of PHMA 12-2387’s left arm, and remained there until her death.

Although hypothetical situations are documented by Richards et al. in a  trauma reconstruction, it is likely thought that the upper limb injuries occurred at the same time as each other, and that the Ursus phalanx represented a part of a decoration (possibly a necklace) worn by the individual in question.  The mechanism of the introduction of the phalanx is likely to have been a devastating crushing injury which rammed the phalanx into the bone, as documented by the surrounding tissue damage.  Richards et al. 2013 (52-53) suggest that the individual was wearing a possible necklace of ‘claws’, with the phalanx having a shamanic connotation or reflecting a high status within the Middle Period horizon cultures.  Ethnographic accounts of Central Californian tribes indicate that shamans were ‘an integral part of the political, economic and legal institutions’ (Richards et al. 2013: 52).  A number of scenarios regarding her possible role within a society are postulated, and although no firm conclusion can be made, the case calls for a unique perspective for a personal osteobiography during the Californian prehistoric period.

Importantly this case study of this unfortunate individual highlights the coming together of the historical, the ethnographic, the osteological and the anatomical.  Whilst the hypothetical situation of the cause of the trauma can be discussed and postulated, it nevertheless stimulates a worthwhile discussion on the role of shamanistic behaviour in prehistoric California and it adds to the importance of understanding the injuries on the living individual, a living osteobiography.  It is an important article and well worth the full read.

Bibliography:

Richards, G., Ojeda, H., Jabbour, R., Ibarra, C., & Horton, C. (2013). Bear phalanx traumatically introduced into a living human: Prehistoric evidence International Journal of Paleopathology, 3 (1), 48-53 DOI: 10.1016/j.ijpp.2013.01.001

Roberts, C. & Manchester, K. 2010.  The Archaeology of Disease. Stroud: The History Press.

Waldron, T. 2009. Palaeopathology. Cambridge: Cambridge University Press.

ResearchBlogging.org

Skeletal Series Part 9: The Human Hip

22 Jan
In this post I shall be discussing and looking at the three main elements that make up the human pelvis (or the pelvic girdle, a homology to the shoulder girdle).  The bones that make up the pelvis are the Ischium, Ilium & the Pubis.  The Sacrum has been discussed in an earlier post on the spine.  During the development of the hip, these three elements remain singular, fusing together during adolescence to become one single unit during early maturity to become the Os Coxa (White & Folkens 2005: 246).

The main elements in the human hip, and as a whole Referred to as the Os Coxa. NB acetabulum faces laterally.

The hip is a fantastic wealth of skeletal knowledge.  The two most basic and fundamental traits of the person, the age and biological sex of the individual, can be found in articles by Brooks & Suchey (1990) and by Patriquin et al. (2005), which both use morphological features of the pelvis to estimate sex and age of the individual under study.  Many muscles also insert and attach along the borders, rims and edges of the pelvis, especially anchoring those that are key in movement during bipedal locomotion (Schwartz 2007: 147).  The hip, and its component parts, are most distinctive in shape and size.  Odd looking, hard to figure out at first, and looking like nothing else (a top heavy hourglass is one view), the Os Coxa can can be hard to identify and orientate, especially in smaller fragments.

Juvenile ilium (top), ischium (bottom right) and pubis (bottom left) (Image credit: Bone Clones 2006).

Excavation
Unfortunately during excavation, the first thing that the pick ax, spade or trowel is likely to hit is the most anterior part of the hip, the pubic symphysis, as in most human burials the body lies prone and face up, in a supine burial (see Brothwell: 3 for other burial positions).  This can lead to destruction of this joint, which can lead to loss of information on age and sex of the individual.  However, during normal inhumation excavation the grave cut can be clearly distinguished, and a pattern of working from top to bottom or bottom to top can help limit the amount of damage during excavation (White & Folkens 2005).

The author excavating a Medieval skeleton in Germany in 2011. Note the damaged anterior aspect of the Pubic Symphysis, which is outlined in red.

Pelvic Anatomy and Elements:
Acetabulum
The acetabulum  makes up the socket to receive the head of the femur (thigh), and is equally made up of a portion of the three elements of the hip which fuse during early adolescence.  This joint is necessarily much more stable then the non-weight bearing shoulder joint- it is much deeper, has the ligamentum teres (a ligament that attaches to the femoral head and the hip) and is covered by much stronger and denser musculature (White & Folkens 2005: 246).  As the main weight bearing joint, the bone is also much denser with thicker cortical bone.
Ilium
The ilium is the largest of the three parts of the os coxa, and sits superiorly above the ischium and pubis, and it is often described as ‘blade like’ (Schwartz 2007: 148) as it is a thin but strong plate of curved bone.  On the lateral side of the blade, three gluteal lines (anterior, inferior & posterior) are visible which are the muscle attachment sites for the large gluteal muscles.  The main landmarks along the upper ridge is the iliac crest, which can be felt on yourself, and begins anteriorly with the anterior superior iliac spine and ends in the posterior superior iliac spine (White & Folkens 2005: 247).  The auricular surface of the medial ilium articulates with the sacrum (and is a very useful age estimator- Buckberry & Chamberlain 2002).  The greater sciatic notch is also generally a good indicator of the biological sex of the individual.

Anatomical landmarks on the right hip (Image credit: Pearson Education 2010).

Ischium
The ischium is the butt bone, literally the bone which takes the weight whilst we are sitting on a chair!  The key features of this element of the hip is that a lot of muscles attach to the posterior ischial tuberosity.  The ischial tuberosity muscle attachments include the origins of the hamstring muscles (semimembranosus, semitendinosus, adductor magnus & biceps femoris) (White & Folkens 2005).  Alongside the pubic bone, the ischium also includes the obturator foramen, a gap (in life covered by a membrane) where a number of internal gluteal muscles converge and provide stability for the hip.
Pubis
The pubic bone makes up the anterior part of the hip as a whole and includes a cartilaginous joint, just above the genitalia in living individuals.  The pubic symphysis, as this joint is called, is also a good indicator of biological sex because of the shape below it (the  pubic arch) and also age because of age related changes in the bony surface of the pubic symphysis (Schwartz 2007: 230).  The pubic bone also includes a superior and inferior pubic ramus, literally the corpus of the bone, which help support numerous muscle attachments, namely the adductors (adductor brevislongus & magnus) of the medial compartment of the thigh.

The  major landmarks of the pelvic bones in anatomical position.

Discussion

For the discussion on the hip we shall talk about septic arthritis (SA).  SA is mostly common in the hip and knee, and rarely presents in the elbow or shoulder.  Although it is rare in the archaeological record, it is nonetheless recorded in a number of examples (i.e. Yukon individuals in the Natural Museum of National History in Washington, US), and it pays to be able to recognise it (Roberts & Manchester 2010: 154).  The condition is fairly uncommon, and the aetiology of SA is when an infection reaches a joint, normally through one of three means- i) the haematogenous route (most common), ii) a penetrating injury or iii) its spread from metaphysis (Marsland & Kapoor 2008).  The bacteria, or germ, normally infects the synovial fluid which may be inflamed from disease or trauma, and ‘proliferation of bacteria cause an inflammatory response by the host with numerous leucocytes migrating into the joint’ (Marsland & Kapoor 2008: 136).

Main outcome of septic arthritis (Image credit: http://www.aidmyarthritis.com).

At this point the variety of enzymes and breakdown products that are produced helps to damage the articular cartilage very quickly, and if left will produce permanent damage (Waldron 2009: 89).  The prognosis is good if treated promptly, however in the archaeological record this is quite unlikely due to the high risks of re-infection and complications such as joint destruction, avascular necrosis (mostly at the hip) & the ‘seeding of infection’ to other places (Marsland & Kapoor 2008: 137).  Again, the diagnosis of septic arthritis in the archaeological record is hindered by confusion with similarities to tuberculous infection, and difficulties in diagnosing multiple diseases that may present themselves on any one individual (Roberts & Manchester 2010: 154).  In the hip, the surface and surrounding area (lunate surface) of the acetabulum would be highly damaged, with a rough appearance and feeling as the bony lytic destruction took hold (Waldron 2009).

Bibliography

Brooks, S. & Suchey, J. M. 1990. Skeletal age determination based on the os pubis: a comparison of the Acsádi-Nemeskéri and Suchey-Brooks methods. Human Evolution 5– N.3: 227-238.

Brothwell, D. R. 1981. Digging Up Bones: The Excavation, Treatment and Study of Human Skeletal Remains.  Ithica: Cornell University Press.

Buckberry, J.L. & Chamberlain, A.T.  2002.  Age estimation from the auricular surface of the ilium: a revised methodAmerican Journal of Physical Anthropology 119: 231-239.

Larsen, C. 1997. Bioarchaeology: Interpreting Behaviour From The Human Skeleton. Cambridge: Cambridge University Press.

Marsland, D. & Kapoor, S. 2008. Rheumatology and Orthopaedics. London: Mosby Elsevier.

Mays, S. 1999. The Archaeology of Human Bones. Glasgow: Bell & Bain Ltd.

Patriquin, M.L., Steyn, M. & Loth, S.R. 2005.  Metric analysis of sex differences in South African black and white pelvesForensic Science International 147: 119-127.

Roberts, C. & Manchester, K. 2010. The Archaeology of Disease Third Edition. Stroud: The History Press.

Schwartz, J. H. 2007. Skeleton Keys: An Introduction to Human Skeletal Morphology. New York: Oxford University Press.

Waldron, T. 2009. Palaeopathology: Cambridge Manuals in Archaeology. Cambridge: Cambridge University Press.

White, T. & Folkens, P. 2005. The Human Bone Manual. London: Elsevier Academic Press.