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
Mutation in what results in osteopetrosis?
CA2
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 were the symptoms of individuals in the 1700s who had scurvy?
Skin turned black, ulcers formed, difficulty breathing, teeth fell out, gum disease
What are the characteristics of Scurvy?
How can you make a diagnosis of osteogenesis imperfecta?
Skin biopsy - analysis of tye I collagen genes or testing of genomic DNA for mutation in COL1A1 and COL1A2
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 role of osteoblasts in bone?
Synthesize, transport and arrange bone into matrix proteins (Collagen type I)
Initiate mineralization (catalyzed by alkaline phosphatase in matrix vesicles)
What is the difference between Osteopenia, osteoporosis, Paget, and Osteomalacia?
What is the rachitic rosary in relation to rickets?
Enlarged chostochondral growth plates
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 the characteristics of osteomyelitis?
Osteomyelitis
Osteomyelitis denotes inflammation of bone and marrow, virtually always secondary to infection . Osteomyelitis may be a complication of any systemic infection but frequently manifests as a primary solitary focus of disease. All types of organisms, including viruses, parasites, fungi, and bacteria, can produce osteomyelitis, but infections caused by certain pyogenic bacteria and mycobacteria are the most common. Currently in the United States, exotic infections in immigrants from developing countries and opportunistic infections in immunosuppressed individuals have made the diagnosis and treatment of osteomyelitis challenging
Staphylococcus aureus is responsible for 80% to 90% of the cases of culture-positive pyogenic osteomyelitis.
individuals with sickle cell disease are predisposed to Salmonella infection.
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.
