Metabolic Bone Disease Flashcards
defined as diminished bone quantity in which the bone is otherwise normal
osteoporosis
bone quantity is normal but the quality of the bone is abnormal in that it is not normally mineralized
osteomalacia
results in excess nonmineralized osteoid
osteomalacia
most common cause of osteoporosis
aging
Main radiographic finding in osteoporosis is
Thinning of cortex
Osteoporosis is most reliably demonstrated in what bone
Second metacarpal at the middiaphysis
Normal metacarpal cortical thickening should be approximately
1/4 to 1/3 the thickness of the metacarpal
Measurement of bone mineral content for the purposes of predicting fracture risk and monitoring response to therapy is usually done by means of _______ which compares a patient’s bone mineral density of the spine and hip wirh that of a healthy 30 year old adult
Dual-energy x-ray absorptiometry (DXA)
True or false: calcium additives have not been shown to reverse the process of primary osteoporosis
True
Can alleviate postmenopausal osteoporosis
Estrogen
Drugs that inhibit osteoclastic acitvity and thus slow bone loss and are commobky prescribed to treat osteoporosis and to prevent bony complications related to osseous metastatic disease as they reduce fracture risk
Biphosphonate drugs
A type of osteoporosis that can be seen in a patient of any age is
Disuse osteoporosis
Radiographic appearance of disuse osteoporosis that is due to osteoclastic resorption in the cortex causing intracortical holes
Patchy appearance of bone
Form of osteoporosis that can mimic a permeative lesion because of multiple cortical holes that project over the medullary space, thus resembling a medullary permeative process
Aggressive osteoporosis
2 Other causes of pseudopermeative process aside from disuse osteoporosis
Hemangioma and radiation
Hemangioma can cause cortical holes in 2 ways, namely
From focal hyperemia causing focal osteoporosis or by the blood vessels themselves tunneling through the cortex
Radiation can cayse cortical holes in bone and mimic a permeative process because of
Death of cortical osteocytes, which can enlarge lacunae in the cortex
3 Differential diagnosis of permeative lesion in young people (<30 yo)
Ewing sarcoma, infection, eosinophilic granuloma
3 Differential diagnosis of permeative lesion in older patients
Multiple myeloma, metastatic carcinomatosis, primary lymphoma of bone
MML
Result of too much nonmineralized osteoid
Osteomalacia
Most common cause of osteomalacia
Renal osteodystrophy
Only finding that is pathognomonic for osteomalacia is a
Looser fracture
Fracture through large osteoid seams
Looser fracture
Looser fracture tend to occur in what body parts (3)
Femur, pelvis, scapula
FPS
Osteomalacia in children is called
Rickets
Causes epiphyseal playes to become flared and irregular and the long bones to undergo bending from bone softening
Rickets
Occurs from excess parathyroid hormone
Hyperparathyroidism
Hormone that causes osteoclastic resorption in bone, which leads to osteoporosis and osteomalacia
Parathyroid hormone
Primary HPT are caused by
Parathyroid adenomas and hyperplasia
Most common cause of HPT is from
Renal disease
Radiographic sign that is Pathognomonic for HPT is
Subperiosteal bone resorption
Subperiosteal bone resorption in HPT is seen most commonly on the (3)
MRS
- Radial aspect of middle phalanges of the hand,
- medial aspect of proximal tibia and
- subchondral bone resorption at sacroiliac joints
Rugger jersey spine is seen in
Hyperparathyroidism
Cystic lesions in hyperparathyroidism that are often expansile and aggressive in apearance
Brown tumors
2 Few skeletal changes seen in hypoparathyroidism
Calvarial thickening and calcification in the basal ganglia
Caused by congenital failure of tissues to respond to PTH. Parathyroid glands are normal in these cases
Pseudohypoparathyroidism
4 Characteristic appearance of patients with pseudohypoparathyroidism
Obesity, round facies, short stature and brachydactyly
Hypothyroidism is a ______ problem, pseudohypoparathyroidism is a ______ problem, and pseudopseudohypoparathyroidism is a ____
Hypothyroidism- parathyroid gland problem
Pseudohypoparathyroidism- end organ problem
Pseudopseudohypoparathyroidism is a mimicker of pseudohypoparathyroidism morphologically
A secreting adenoma or hyperplasia of the anterior lobe of the pituitary gland will result in
Accelerated bone growth
3 Skull findings in acromegaly
Calvarial thickening, enlarged sinuses, enlarged sella turcica
Appearance of jaw in acromegaly
Prognathic
Terminal tufts of distal phalanges in acromegaly appears as
Spade appearance/shovel
Has been used as a sign of acromegaly
Thickening of heel pad adjacent to calcaneus
Rare manifestation of hyperthyroidism that occurs only after prior thyroidectomy
Thyroid acropachy
Useful differential point that can be used to tell thyroid acropachy from other causes of diffuse periostitis
Periostitis involving the ulnar aspect of fifth metacarpal
Decreased thyroid secretion
Cretinism
Epiphyses appears stippled in this metabolic disease
Thyroid gland hypofunction or cretinism
Diffuse increase in bone density
Osteosclerosis
By far most common disease in which osteosclerosis is seen
Renal osteodystrophy
The sine qua non of renal osteodystrophy is
Subperiosteal bone resorption
Subperiosteal bone resorption in renal osteodystrophy is reliably seen at the
Radial aspect of middle phalanges of hands
Fish vertebrae is seen in
Sicke cell disease
Bone infarcts and step-off deformities of vertebral body endplates, avascular necrosis of the hip are seen in
Sickle cell disease
Also called angogenic myeloid dysplasia, it is caused by progressive fibrosis of the marrow in patients older than 50 years of age
Myelofibrosis
Myelofibrosis leads to
Anemia with marked splenomegalynand extramedullary hematopoiesis
Hereditary abnormality that results in extremely dense bones throughout the skeleton
Osteopetrosis
2 forms of osteopetrosis
Congenita and tarda
Form of osteopetrosis that can be lethat
Congenita
Form of osteopetrosis that is milder
Tarda
Characteristic finding is bone-in-bone appearance often seen in the vertebral bodies in which vertebrae have a small replics of the vertebral body inside the normal one
Osteopetrosis
Sandwich vertebrae is seen in
Osteopetrosis
Sandwich vertebrae in osteopetrosis can be differentiated from rugger jersey spine in rickets by noting that
The bands of sclerosis in sandwich vertebrae are denser
Other congenital abnormality with dense bomes that shoild be considered in the differential diagnosis of osteosclerosis. These patients are typically short and have hypoplastic mandibles
Pyknodysostosis
Distinguishing radiographic finding of pyknodysostosis
Acroosteolysis with sclerosis
acro = point; osteo = bone; lysis = dissolve
In this condition, the distal phalanges often have the appearance of chalk that has bern put into a pencil sharpener
Pyknodysostosis
Pyknodysostosis is aka
Toulouse-Lautrev syndrome
Can cause uniformly increased bone density, thickened small bowel folds with nodules and urticaria pigmentosa
Mastocytosis
Paget’s disease classically causes
Bony enlargement
Paget’s disease commonly occur in
Pelvis, with thickened iliopectineal line on pelvic brim
3 Distinct radiographic phases of Paget’s disease
Lytic, sclerotic and mixed lytic and sclerotic phase
Lytic phase of Paget disease usually present as
Sharp leading edge called flame-shaped or blade-of-grass leading edge
In a long bone, with sole exception of the tibia, Paget disease always starts at the
End of bone
Radiographic finding that patients with fluorosis often have is
Ligamentous calcification
Calcification of sacrotuberous ligament is said to be characteristic of
Fluorosis
