Diseases of bone Flashcards
What are three types of bone disease?
- Genetic - osteogenesis imperfecta, osteopetrosis (Albers-Shonberg), achondroplasia
- Metabolic (vitamin D turnover, PTH, osteomalacia, rickets, osteoporosis)
Infective - osteomyelitis AND Malignancy - osteosarcoma and Ewing’s,
What is a way of dividing up the skeleton?
Axial and appendicular
What are three sections of long bone?
Epiphysis, metaphysis, diaphysis
What is a Haversian canal and Volkmann canal?
Haversian canals are a series of microscopic tubes in the outermost region of bone called cortical bone. They allow blood vessels and nerves to travel through them to supply the osteocytes.
Volkmann canal interconnect the haversian canals with each other and the periosteum. They usually run at obtuse angles to the haversian canals and contain anastomosing vessels between haversian capillaries.
What percentage of the bone is water?
40%
What percentage of the bone is inorganic and organic?
65 and 35% respectively
What is woven bone?
What are the key characteristics of Achondroplasia?
AD disease
Mutation in FGFR3
Arginine substituted for glycine
Inhibits chondrocytes
Shortening of long bones
Homozygous form problems
What are the key characteristics of Osteogenesis imperfecta?
AD disease
Brittle bones
OI Type 1 - 60-80% of cases, normal stature, hyperflexibility, hearing loss, discoloration of sclera.
OI Type 2 - fatal, abnormal blue-black sclera due to thinning
What type of mutation is OI?
AD
in collagen 1
What is OI type 1?
OI Type 1 - 60-80% of cases, normal stature, hyperflexibility, hearing loss, discoloration of sclera.
Collagen 1 mutation
What is OI type 2?
OI Type 2 - fatal, abnormal blue-black sclera due to thinning
What is another name for osteopetrosis?
Albers Shonberg disease
Marble bone disease
What are the key characteristics of osteopetrosis?
AR
Carbonic anhydrase II deficiency
Reduced osteoclast activity
Osteopetrosis, literally “stone bone”, also known as marble bone disease or Albers-Schönberg disease, is an extremely rare inherited disorder whereby the bones harden, becoming denser, in contrast to more prevalent conditions like osteoporosis,
What is the mutation in osteopetrosis?
Carbonic anhydrase II, AR
What condition could this be?
Osteopetrosis
What is the difference for primary and secondary osteoporosis?
What are 5 key features of rickets?
Frontal bossing
Rachitic rosary
Harrisons sulcus
Bowing of legs
Pectus carinatum
What are the different types of hyperparathyroidism?
Primary hyperparathyroidism is when there’s a problem within the parathyroid gland itself, usually a benign (non-cancerous) tumour of the gland.
Secondary hyperparathyroidism is when the glands are fine but a condition, like kidney failure, lowers calcium levels and causes the body to react by producing extra parathyroid hormone.
Tertiary hyperparathyroidism is when long-standing secondary hyperparathyroidism starts to behave like primary hyperparathyroidism.
What is a brown tumour?
The brown tumor is a bone lesion that arises in settings of excess osteoclast activity, such as hyperparathyroidism. They are a form of osteitis fibrosa cystica. It is not a neoplasm, but rather simply a mass.
What is Pott’s disease?
A type of osteomyelitis caused by TB that affects intervertebral discs of throacic and lumbar region
How can Pott’s disease present?
Bone pain
Kyphosis
What are two primary bone malignancies that you should know about?
Osteosarcoma and Ewing’s sarcome
What is a key feature of osteosarcoma?
Sunburst pattern
Codman’s triangle
