2.1.1 Bone and Joint Pathology I Flashcards
What are some characteristics of osteopetrosis?
Draw a diagram of scurvy?
What are some of the clinical features of osteopetrosis?
Severe infantile osteopetrosis is autosomal recessive and usually becomes evident in utero or soon after birth. Fracture, anemia, and hydrocephaly are often seen, resulting in postpartum mortality. Affected individuals who survive into their infancy have cranial nerve defects (optic atrophy, deafness, and facial paralysis) and repeated—often fatal—infections because of leukopenia, despite extensive extramedullary hematopoiesis that can lead to prominent hepatosplenomegaly. The mild autosomal dominant form may not be detected until adolescence or adulthood, when it is discovered on x-ray studies performed because of repeated fractures. These individuals may also have mild cranial nerve deficits and anemia.
What is this an image of?
A, Recent fracture of the fibula. B, Marked callus formation 6 weeks later.
What is this an image of?
Osteoporosis
What is this an image of?
Paget Disease of Bone
Hyperostosis frontalis interna
Paget disease shows remarkable histologic variation over time and from site to site. The hallmark is a mosaic pattern of lamellar bone, seen in the sclerotic phase. This jigsaw puzzle-like appearance is produced by unusually prominent cement lines, which join haphazardly oriented units of lamellar bone
What is the role of Osteoclasts on bone?
Bone reabsorption - breaks down bone into elemental units - release into microenvironment
What are these images of?
Paget Disease
Mosaic pattern
What is this an image of?
Osteoporosis
What are some of the treatments associated with osteoporosis?
What are the characteristics of Osetogenesis imperfecta?
What are some of the hormonal influences on osteoporosis?
What is this an image of?
Avascular necrosis
Wedge shaped - triangular infarct
What is this an image of?
OSTEOPETROSIS: overgrowth of cancellous bone causes loss of marrow and pancytopenia
How can age and reduced physical activity affect osteoporosis?
What is Paget Disease of the bone?
Paget Disease (Osteitis Deformans)
Paget disease is a disorder of increased, but disordered and structurally unsound, bone mass. This unique skeletal disease can be divided into three sequential phases: (1) an initial osteolytic stage, (2) a mixed osteoclastic-osteoblastic stage, which ends with a predominance of osteoblastic activity and evolves ultimately into (3) a final burned-out quiescent osteosclerotic stage
What is this an image of?
Osteomalacia
What is this an image of?
Very dense bones throughout skeleton
Osteopetrosis
What is this an image of?
Decrease in collagen makes sclera translucent allowing partial visualization of underlying choroid
Osteogenesis imperfecta
What are some other characterisitcs of fracture healing?
How does FGFR3 relate to achondroplasia? Describe the inheritance of it?
What are some of the clinical characteristics of Paget Disease?
What are the characteristics of avascular necrosis (osteonecrosis)?
Infarction of bone and marrow is a relatively common event that can occur in the medullary cavity or involve both the medulla and cortex. Most cases of bone necrosis stem from fractures or corticosteroid administration. A diverse set of other conditions also predispose to osteonecrosis ( Table 26-5 ). All are believed to lead to vascular insufficiency through mechanical injury to blood vessels, thromboembolism, external pressure on vessels, or venous occlusion.
What are the characteristics of Scurvy?
What is Ricket’s?
Impaired absorption of Ca2+ and PO4.
Growing bones can get enough Ca2+ or PO4 to support mineralization - become soft and flexible
What is the difference between Osteopenia, osteoporosis, Paget, and Osteomalacia?
What are the characteristics of a bone fracture?
What are the characterisitics of Achondroplasia?
Reduction in proliferation of chondrocytes
What is this an image of?
Rickets on XRAY
What are the symptoms and treatment of osteomyelitis?
What are the covered parts?
What are some of the affectors of osteoporosis?
What are the characteristics of Osteopetrosis?
Osteopetrosis, also known as marble bone disease and Albers-Schönberg disease, refers to a group of rare genetic diseases that are characterized by reduced bone resorption and diffuse symmetric skeletal sclerosis due to impaired formation or function of osteoclasts. The term osteopetrosis reflects the stone-like quality of the bones. However, the bones are abnormally brittle and fracture easily, like a piece of chalk. Osteopetrosis is classified into variants based on both the mode of inheritance and the severity of clinical findings.
Pathogenesis.
Most of the mutations underlying osteopetrosis interfere with the process of acidification of the osteoclast resorption pit, which is required for the dissolution of the calcium hydroxyapatite within the matrix. Examples include autosomal recessive defects in the gene for the enzyme carbonic anhydrase 2 ( CA2 ). CA2 is required by osteoclasts and renal tubular cells to generate protons from carbon dioxide and water. The absence of CA2 prevents osteoclasts from acidifying the resorption pit and solubilizing hydroxyapatite, and also blocks the acidification of urine by the renal tubular cells. Other forms of the disease are caused by mutations in CLCN7, which encodes a proton pump located on the surface of osteoclasts.
