Paleopathological Conditions

Question 1

Osteitis

Answer 1

What is it?
Inflammation of the cortical bone

What does it look like?
Bone may be hypertrophic & heavy

*Appears radiopaque (white) on radiographs

Question 2

Osteomyelitis

Answer 2

What is it?
Inflammation of the medullary cavity

What does it look like?
Must have sequestrum (dead bone), involucrum (sheath of new bone) and cloaca(e)

Question 3

PNB (Periosteal New Bone)

Answer 3

What is it?
Inflammation of the periosteum

What does it look like?
Woven (grey/brown in colour, disoriganized) or Lamellar (normal colour, striated)

Question 4

Scurvy

Answer 4

What is it?
Lack of vitamin C = defective collagen (can stop bone growth and weaken connective tissue around teeth)

What does it look like?
- Porosity and new bone in areas of muscle attachment on SCAPULAE & SKULL
- PNB on long bones

Question 5

Radiographical Signs of Scurvy

Answer 5

1) White Line of Frenkel – dense white line at metaphysis
2) Trummelfeld’s Zone – line of decreased radio-density proximal or distal to (WLF)
3) Pelkan’s spurs – small spurs of bone protruding laterally and medially from WLF
4) Wimberger’s ring – dense calcification around ephiphyses

Question 6

Rickets

Answer 6

What is it?
Lack of vitamin D = ineffective mineralization resulting in ‘soft’ weak bones

What does it look like?
PRIMARY…
- Metaphyses appear cupped and flared
- Rachitic rosary = nodular prominences at costochondral junction of ribs
- Delayed closure of fontanelles
SECONDARY…
- Bowing deformities
- Medial tilting of distal tibiae
- Coxa vara (more acute angle) of femoral neck
- Flattening of cranial bones

Question 7

Radiographical Signs of Rickets

Answer 7

• Metaphyseal margin irregular & frayed
• Metaphysis widened and cupped
• General osteopenia of cortex
• Loss of cortico-medullary distinction
• Coarsened trabeculae

Question 8

Osteomalacia

Answer 8

What is it?
- Lack of vitamin D = ineffective mineralization resulting in ‘soft’ weak bones
- Considered adult Rickets

What does it look like?
Less obvious skeletal changes than Rickets…
- Straightening of ribs
- Sternum displaced anteriorly
- Scoliosis (M-L) or kyphosis (A-P) curvature may develop
- Lower lumbar vertebrae and acetabulae can protrude into pelvic inlet
- Looser’s zones = large seams of osteoid which appear as pseudo-fractures radiographically

Question 9

Osteoporosis

Answer 9

What is it?
More bone removed per remodeling unit due to increased osteoclastic and decreased osteoblastic activity

What does it look like?
- Lower weight of bone
- Occurs along endocortical surface, creating a trabecular structure at the margins of the medullary cavity
- Typically, would see fracture patterns (likely hip, Colle’s and vertebral)

Question 10

Paget’s Disease

Answer 10

What is it?
Unknown cause, mostly affects older individuals
Rapid disorganized remodeling

What does it look like?
- Typically involves the skull, vertebrae, femur or tibia
- Bones appear hypertrophic, but are structurally weak and prone to bend and fracture
- In cross section, cortical bone has ‘honeycomb’ appearance with lots of gaps
- Cortical surfaces have porous, dense woven bone

Question 11

Radiographical Signs of Paget’s Disease

Answer 11

• Visible in lytic phase: Flame sign = area of v-shaped translucency that extends in distal to proximal direction
• Visible in mixed/sclerotic phase: thick radio-opaque cortex, cotton wool skull, picture frame vertebra, ivory vertebra, Looser’s zones

Question 12

Three Phases of Paget’s Disease

Answer 12

1) Lytic (increased OC activity)
2) Mixed (increased OC and OB activity)
3) Sclerotic (OB increased, OC decreased)

Question 13

Porotic Hyperostosis

Answer 13

What is it?
Caused by expansion of the diploe and thinning of the outer table

What does it look like?
Porosity and pitting of the outer table of skull

*Radiographical signs = ‘hair on end’ appearance

Question 14

Cribra Orbitalia

Answer 14

Similar porous, pitted appearance to Porotic Hyperostosis, but primarily isolated to orbital roof

Question 15

Dental Enamel Hypoplasia

Answer 15

What is it?
Caused by stress-induced disruption of amelogenesis - the process that produces enamel

What does it look like?
Bands or pits on dental enamel

Question 16

Interglobular Dentine

Answer 16

What is it?
Poorly mineralized dentine arising from unfused calcospherites in vitamin D/Ca deficient individuals

What does it look like?
Dark blobs of dentine seen in cross section of tooth under a microscope

Question 17

Osteosarcoma (primary benign)

Answer 17

An outgrowth of bone, forms out of growth plate but can be seen on surface of bone

Can appear ‘stalked’ or ‘pinched’

Question 18

Osteosarcoma (primary malignant)

Answer 18

What is it?
Tumor that metastasizes (spreads to other areas of the body)

What does it look like?
- Arises directly from cortex, often near metaphysis
- Primarily affects long bones
- More disorganised and spiculed than benign osteosarcomas

Question 19

Radiographical Signs of Malignant Osteosarcomas

Answer 19

• Sunburst appearance and/or Codman’s triangle (represents aggressive, fast-forming periostitis)
• Destruction of medullary cavity

Question 20

Osteosarcoma (secondary malignant)

Answer 20

What does it look like?
- Lesions can be lytic (holes with ‘chewed’ edges), sclerotic (new bone formation, sometimes ‘sunburst’) or mixed
- Multiple Myeloma – increased OC activity, decreased OB activity (lytic), lots of little holes on scapula, skull, pelvis, vertebrae and ribs

*Sclerotic lesions appear radiopaque

Question 21

Lumbarisation

Answer 21

First sacral vertebra does not fuse with the rest of sacrum (less common)

Question 22

Sacralisation

Answer 22

Fifth lumbar vertebra fuses with sacrum

Question 23

Scoliosis

Answer 23

• Lateral curvature of the spine
• Vertebrae appear asymmetrical or wedge-shaped
• Curved spinous processes, short and fat transverse processes on convex side, long and thin on concave side

Question 24

Spina Bifida

Answer 24

What is it?
- Malformations of the neural canal (neural tube defect, 4th week gestation)
- In serious cases, spinal cord and nerves protrude through skin (spina bifida cystica)

What does it look like?
Posterior arch of neural canal does not fuse, most often in sacral and lumbar vertebrae

Question 25

Spondylosis

Answer 25

What is it?
- Really just a stress fracture, likely with some congenital predisposition
- May cause back pain
- Complication is spondylolisthesis, vertebral body slips forwards, out of alignment

What does it look like?
Detachment of neural arch at pars interarticularis (isthmus)

Question 26

Congenital Hip Dislocation

Answer 26

Shallow acetabulum, usually unilateral, bony changes as a consequence surrounding the hip joint

Question 27

When during gestation will most congenital conditions occur?

Answer 27

20-22 weeks

Question 28

Club Foot (Talipes Equinovarus)

Answer 28

What is it?
- Foot rotated inwards at ankle (fixed in adduction
- Ligaments shortened
- Idiopathic, probably neuromuscular

What does it look like?
Calcaneus, navicular and cuboid medially rotated in relation to talus

Question 29

Achondroplasia

Answer 29

What is it?
Form of dwarfism in which ossification of cartilage is inhibited

What does it look like?
Abnormally small bones, primarily long bones, but also parts of the spine and skull

Question 30

Osteoarthritis

Answer 30

*Would need eburnation or at least two of these features to diagnose OA):
- Eburnation at joint surfaces
- Osteophyte formation at joint margins and surfaces (enthesophytes)
- Contour change of joint
- Pitting of joint surface

Question 31

Primary OA

Answer 31

OA caused by joint morphology, age-related degeneration, obesity, genetic predisposition

Question 32

Secondary OA

Answer 32

OA caused by trauma, disease

*In clinical cases, most commonly affect joints are knee, hip, hand

Question 33

Ankylosing Spondylitis

Answer 33

What is it?
Cause unknown (maybe auto-immune disorder linked to prostate gland?)
More common in males, age of onset = 20 years old

What does it look like?
- “Bamboo spine”
- Small syndesmophytes form along superior and inferior margins of vertebral bodies
- Joint space maintained
- No skip lesions
- Starts in lumbar region and moves cranially
- Ribs, as well as superior and inferior facets may also fuse to vertebral bodies

Question 34

Reactive (Reiter’s) Arthritis

Answer 34

What is it?
- Associated with urethral infections, gastro-intestinal infections and STDs
- Causes inflammation of joints and tendons
- Most common in men aged 50+

What does it look like?
- Asymmetrical erosions at join surfaces
- Preferentially affects the feet
- Accompanied by new bone formation, particularly on talus, MT shafts and at entheses
- Ankylosis of foot bones
- Bi-lateral SI involvement
- Fusion of spine W/ skip lesions

Question 35

Syndesmophytes

Answer 35

Bony growth inside ligament

Question 36

Ankylosis

Answer 36

A stiffness of a joint due to abnormal adhesion and rigidity of the bones of the joint

Question 37

Psoriatic Arthritis

Answer 37

• Erosions at joint margins, asymmetrical
• Some new bone formation
• Proximal end of DP widens, while distal end of IP resorbs (‘pencil-in-cup’)
• Ankylosis may occur causing shortening of finger
• Uni-lateral S-I involvement
• Fusion of spine with skip lesions

Question 38

Rheumatoid Arthritis

Answer 38

What is it?
- Autoimmune disease, attacks synovial membrane
- Inflamed synovium thickens to form a pannus (causes destruction of cartilage and subchondral bone)
- Most common in females, on-set around early 30s

What does it look like?
- Erosions at joint margins (where synovium attaches – i.e. epicondyles of distal femur)
- Erosions are symmetrical
- Very little new bone formation
- Typically seen in hands, but also cervical spine, wrist, elbow, knee
- Ulnar drift/deviation = bending of fingers towards pinky finger, result of swelling due to RA

Question 39

Gout

Answer 39

What is it?
- Results from build-up of uric acid in blood
- Most common in males over 50 and post-menopausal women

What does it look like?
- Erosion in para-articular areas of feet, usually asymmetrical
- In chronic cases, tophaceous masses (tophi) form and destroy bone
- ‘Punched-out’ appearance with over-hanging edge (Martel’s hook)