Osteomalacia/Rickets

Question 1

Pathology of osteomalacia

Answer 1

Qualitatively deficient bone – abidance of unmineralized osteoid - the ratio of osteoid to mineral is defective

Question 2

Osteomalacia is related to a deficiency of _____, _______ or ________. These deficiencies are related to what causes?

Answer 2

calcium, vitamin D or phosphorus

Dietary deficiency, liver/GI/renal disease, sunlight disease

Question 3

What organ is a powerful controller of bone density?

Answer 3

Kidney

Question 4

What are the precursors for vitamin D?

Answer 4

Diet, sunlight, 1st hydro in liver, 2nd hydro in kidney

Question 5

Osteomalacia is defective in quality thus making osteomalacia a ________.

Answer 5

Bone softening disease

Question 6

A pt. with osteomalacia will present with:

Answer 6

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

Question 7

List the vitamin D pathway

Answer 7

UV light —> cholesterol/ Vit D3 in skin —> 25 hydroxy Vit D in liver —-> 1, 25 DCF in kidney

Question 8

T/F both liver and kidney disease can cause osteomalacia as well as sunlight or dietary deficiency

Answer 8

TRUE

Question 9

What is the active form of Vit D

Answer 9

1, 25 DCF in the kidney

Question 10

Radiographic features of Osteomalacia

Answer 10

• 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

Question 11

Seam/zone of unmineralized osteoid is most commonly seen in what structures?

Answer 11

Rami, axillary border of snap, ribs, bony pelvis, tibia, femur (NOT the spine)

Question 12

Deformities of weight bearing bones would include

Answer 12

Triradiate pelvis, acetabular protrusion, femoral/tibial bowing, kyphoscoliosis, endplate concavity, bell-shaped thorax due to diaphragm pulling in on rib cage

Question 13

Pseudo fractures seen ONLY in bone softening disease. Most common Bone softening Diseases include:

Answer 13

Osteomalacia/rickets
Paget’s Disease
Polyostotic fibrous dysplasia

Question 14

AKA for pseudofracturs

Answer 14

Looser lines
Milkman's syndrome
Increment fractures
Osteoid seams
Umbauzonen

Question 15

Explain Ricekts

Answer 15

Pediatric osteomalacia with same etiologies, may begin as early as 6 - 12 months

Question 16

Classic radiographic finding in rickets

Answer 16

Zone of mineralization disappears

Question 17

Explain Renal Rickets

- aka?

Answer 17

Renal tubular loss of phosphorus

- Resistant/refractory rickets

Question 18

When renal rickets is occurring in combination with secondary HTP this is called

Answer 18

Renal Osteodystrophy

Question 19

Clinical findings of rickets include:

Answer 19

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

Question 20

Define trumpeting

Answer 20

Expansion of metaphysis

Question 21

Most common cause of Rickets

Answer 21

Kidney/renal disease

Question 22

X- linked hypophosphatemia is

- What syndrome is this associated with?

Answer 22

genetically transmitted x-linked dominant trains where renal tubular loss of phosphate is resistant to VitD administration
This is part of Falcon Syndrome

Question 23

In childhood rickets what is the child’s stature like?

Answer 23

its are short, bowlegged and stocky

Question 24

In adult rickets, they will develop

Answer 24

Ligament ossification wich ma resemble DISH

- decreased pedicle length — lumbar spinal stenosis

Question 25

Hypophosphatasia

Answer 25

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