Osteomalacia/Rickets Flashcards
Pathology of osteomalacia
Qualitatively deficient bone – abidance of unmineralized osteoid - the ratio of osteoid to mineral is defective
Osteomalacia is related to a deficiency of _____, _______ or ________. These deficiencies are related to what causes?
calcium, vitamin D or phosphorus
Dietary deficiency, liver/GI/renal disease, sunlight disease
What organ is a powerful controller of bone density?
Kidney
What are the precursors for vitamin D?
Diet, sunlight, 1st hydro in liver, 2nd hydro in kidney
Osteomalacia is defective in quality thus making osteomalacia a ________.
Bone softening disease
A pt. with osteomalacia will present with:
mm. weakness
bone pain on palpation
deformities in the pelvis/femur/tibia/spine
Compression fracture deformities in the spine
Pelvis will have sinking leading to acetabular protrusion, sacrum can sink into pelvis
List the vitamin D pathway
UV light —> cholesterol/ Vit D3 in skin —> 25 hydroxy Vit D in liver —-> 1, 25 DCF in kidney
T/F both liver and kidney disease can cause osteomalacia as well as sunlight or dietary deficiency
TRUE
What is the active form of Vit D
1, 25 DCF in the kidney
Radiographic features of Osteomalacia
- Coarsened trabecular pattern - loss of trabecular bone
loss of cortical definition - Pseudo fractures
= bone softening findings
= Seam/zone of unmineralized osteoid; loser lines - Deformities - weight bearing bones
Seam/zone of unmineralized osteoid is most commonly seen in what structures?
Rami, axillary border of snap, ribs, bony pelvis, tibia, femur (NOT the spine)
Deformities of weight bearing bones would include
Triradiate pelvis, acetabular protrusion, femoral/tibial bowing, kyphoscoliosis, endplate concavity, bell-shaped thorax due to diaphragm pulling in on rib cage
Pseudo fractures seen ONLY in bone softening disease. Most common Bone softening Diseases include:
Osteomalacia/rickets
Paget’s Disease
Polyostotic fibrous dysplasia
AKA for pseudofracturs
Looser lines Milkman's syndrome Increment fractures Osteoid seams Umbauzonen
Explain Ricekts
Pediatric osteomalacia with same etiologies, may begin as early as 6 - 12 months
Classic radiographic finding in rickets
Zone of mineralization disappears
Explain Renal Rickets
- aka?
Renal tubular loss of phosphorus
- Resistant/refractory rickets
When renal rickets is occurring in combination with secondary HTP this is called
Renal Osteodystrophy
Clinical findings of rickets include:
mm. tetany Irritability Weakness Delayed development Small stature Bone deformities/bowing Enlargement around growth plates (trumpeting) and rib ends (rachitic rosary) **Loss of zone of mineralization
Define trumpeting
Expansion of metaphysis
Most common cause of Rickets
Kidney/renal disease
X- linked hypophosphatemia is
- What syndrome is this associated with?
genetically transmitted x-linked dominant trains where renal tubular loss of phosphate is resistant to VitD administration
This is part of Falcon Syndrome
In childhood rickets what is the child’s stature like?
its are short, bowlegged and stocky
In adult rickets, they will develop
Ligament ossification wich ma resemble DISH
- decreased pedicle length — lumbar spinal stenosis
Hypophosphatasia
Rare genetic disorder related to low serum alkaline phosphatase production by osteoblasts
- resembles ricekts
- Cannot get Ca++ and phosphorus “linked” on so cannot get enough mineral onto osteoid
Quality problem of bone due to inability to mineralize
