Bone development disorders

Question 1

What is the term for a hereditary disorder caused by abnormal synthesis of type-1 collagen?

Answer 1

Osteogenesis imperfecta

Question 2

What is the other name for osteogenesis imperfecta?

Answer 2

Brittle bone disease

Question 3

What are 5 defining features of osteogenesis imperfecta?

Answer 3

1. Bone deformity & short stature
2. Blue sclerae
3. Opalescent teeth
4. Deafness
5. Wormian bones (extra irregular bones in skull)

Question 4

What medications can be used to treat osteogenesis imperfecta?

Answer 4

Bisphosphonates: inhibit osteoclast activity to increase bone density

Question 5

What is the term for a congenital disorder of connective tissue causing skeletal, ocular, and cardiovascular abnormalities?

Answer 5

Marfan syndrome

Question 6

What is the underlying cause for Marfan syndrome?

Answer 6

Mutation in the gene that encodes the connective protein fibrillin-1, which is a component of ECM (including elastic fibers)

Question 7

What are 5 skeletal characteristics of Marfan syndrome?

Answer 7

1. Excessive height and long extremities
2. Arachnodactyly
3. Joint laxity
4. Pectus excavatum/carinatum
5. Kyphosis/scoliosis

Question 8

What are 3 ocular characteristics of Marfan syndrome?

Answer 8

1. Ectopia lentis: partial dislocation of lenses of eyes
2. Retinal detachment
3. Severe myopia

Question 9

What are 2 cardiac complications associated with Marfan syndrome?

Answer 9

1. Mitral valve prolapse
2. Aortic necrosis, causing aortic valve incompetence and aortic dissection

Question 10

What is the term for a hereditary failure of osteoclasts to resorb bone?

Answer 10

Osteopetrosis

Question 11

What is the other term for osteopetrosis?

Answer 11

Marble bone disease

Question 12

What are 4