Metabolic disordmmmmmmmmmmmmmmmmmers.ppt

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1. Metabolic disorders
Presented by
Dr. Karrar Kareem
Orthopedic surgeon
2022-2023

2. Objectives
Students are able to diagnose different
types of metabolic bone disease
Treatment of all types metabolic bone
disease

3. Bonecomposition
Bone consists of collagenous matrixwhich is
impregnated with mineral salts and populated by cells.
The matrix:
Composed of type I collagen lying in
mucopolysaccharide ground substance.
Bone minerals:
Almost half the bone volume is mineral material, mainly
calcium and phosphate.
Over 98% of the body's calcium and 85% of its
phosphorus are tightly packed in bone and capable of
only slow exchange.

6. Bone cells types
Bone is composed of four different cell
types;osteoblasts, osteocytes, osteoclasts
and bone lining cells.
Osteoblasts, bone lining cells and osteoclasts are
present on bone surfaces and are derived from
local mesenchymal cells called progenitor cells

7. Two different types of bone
Compact bone:is
dense to the
naked eye it is
found where
support is matter
like femur .
Cancellous bone
:has honeycomb
appearance , like
vertebrae.

8. Synthesis and homeostasis
of vitamin D

9. Osteoporosis:
There is significant decrease in bone mass per
unit volume of bone tissue and this is
accompanied by increased fragility of the bone.
So it is the state in which the bone is mineralized
but its structure is abnormally porous and its
strength is less than normal for person of that
age and sex.

11. Demographics
Male: female ratio is 1:4
Men have a higher prevalence of secondary osteoporosis (60%)
including
hypogonadism
glucocorticoid excess
alcoholism
Postmenopausal osteoporosis is highest in women aged 50-70 years
Senile osteoporosis begins after 70 years
Secondary osteoporosis begins at any age
Fractures
Vertebral body > peritrochanter femur> distal radius
Wrist fractures occur most commonly at age 50-60 years
Vertebral fractures occur most commonly at age 60-70 years
Hip fractures occur most commonly at age 70-80 years

12. Primaryosteoporosis
Usually manifests as an exaggerated form of the
physiological bone depletion. that normally accompanies
ageing and loss of gonadal activity.
Two forms:
A) early post menopausal osteoporosis:
characterized by rapid bone loss due to
increased osteoclasts resorption {type I or high
turn over osteoporosis}
B) Senile osteoporosis{ Type II or slow turnover
osteoporosis}:is less well defined which
emerges in very elderly people and is due to
gradual slow down of osteoblasts activityand
dietary insufficiency and chronic ill health.

13. Post menopausal osteoporosis:
Risk
factors:

14. Clinical features:
Women at or near
menopause 50-70 years
develops back pain and
increased thoracic
kyphosis ,
The height is diminished,
Some times the first
clinical event is low energy
fracture of the distal
radius or one of the other
bone ends.
Mainly vertebra and distal
radius

15. Radiographs
Indications
suspicion of fracture
loss of height
pain in thoracic or lumbar spine
Recommended views
lateral spine radiograph
AP pelvis or hip
Findings
thinned cortices
Loss of trabecular bone
kyphosis
codfish vertebra
Sensitivity and specificity
usually not helpful unless > 30% bone loss

17. Biochemical test
DEXA osteoporosis having a T-score>2.5standard
of deviations below the peak bone mass of a 25-
year-old individual.

18. •DEXA Scan definitions
•BMD
•Absolute, patient-specific score
determined from certain
anatomic areas
•T-Score
•BMD relative to normal young
matched controls (30-year-old
women)
•Z-Score
•BMD relative to similar-aged
patients
•Osteopenia
•L2-4 lumbar density of1
to2.5standard of deviations (T
score -1 to -2.5) below the peak
bone mass of a 25-year-old
individual
•Osteoporosis
•L2-4 lumbar density
>2.5standard of deviations (T
score <-2.5) below the peak bone
mass of a 25-year-old individual

19. Prevention and treatment:
Bone densitometry can be used to identify women at risk to
develop fracture.
Women approaching menopause should be advised to maintain
adequate levels of dietary calcium and vitamin D ,to keep up
with physical activity. and avoid smoking and consumption of
alcohol.
Estrogen medications(hormonal replacement therapy):
the most effective way of reducing risk of fracture and maintain
bone density.
Biphosphonates : useful alternative to hormonal replacement
thepy.
Eg: alendronate; gastrointestinal side effects are bothersome.
Calcitonin: is also used in form of injections or nasal spray.

20. Senileosteoporosis
The classical event is a fracture of the pelvis
and hip region
Femoral neck usually after minor trauma
x-ray:loss of trabecular markings in the
femoral neck, and the spine or old
compression fracture of vertebrae
serum biochemistry is normal.

21. Senileosteoporosis

22. Treatment:
initially directed at management of fracture this
often require internal fixation. the sooner these
patients are mobilized and rehabilitated the
better.
Treatment of accompanied disease. good dietary
supplement of calcium and vitamin D.
And use of hormonal replacement therapy and
bisphosphonate in management.

23. Secondaryosteoporosis:
Hyper cortisonism:
Glucocorticoid overload due to endogenous
cushing'sdisease or prolong treatment with
corticosteroid
This results in severe osteoporosis.
Treatment is problematic since the corticosteroid
medications may be essential for control some
generalized disease.
So we have to keep corticosteroid medication to
minimum dose and supplement of high
calcium(1500mg) daily. also HRT and
biphosphonates is important.

24. Other causes
Gonadal hormone insufficiency:
Hyperthyroidism:
Alcohol abuse
Immobilization: hypercalciemia and
hypercalciuria

25. Ricketsandosteomalacia
Different expression of the same disease.
Inadequate mineralization of the bone .therefore
the bone soften.
The inadequacy may be due to calcium deficiency,
hypo-phosphatemiaor defect any where along
the metabolic pathway of vitamin D.
Pathology:
Inability to calcify the intercellular matrix in the
deeper layer of the physis.

26. Osteoporosis vs. Osteomalacia
•Osteroporosis •Osteomalacia
•Defintion
•Reduced bone mass,
normal mineralization
•Bone mass variable,
reduced mineralization
•Age
•Postmenopausal (Type
I) or elderly (Type II)
•Any age
•Etiology
•Endocrine abnormality,
age, idiopathic,
inactivity, alcohol,
calcium deficiency
•Vit D deficiency or
abnormal vit D pathway,
hypophosphatemia,
hypophosphatasia, renal
tubular acidosis
•Symptoms and
signs
•Pain and tenderness at
fracture site
•Generalized bone pain
and tenderness
•Xray
•Axial fracture
predominance
•Appendicular fracture
predominance,
symmetric, includes
pseudofractures(Looser
zones)
•Serum Ca •Normal •Low or normal
•Serum PO4 •Normal •Low or normal
•ALP •Normal
•Elevated (except
hypophosphatasia)
•Urinary Ca •High or normal
•Normal or low (high in
hypophosphatasia)
•Bone biopsy
•Tetracycline labeling
normal
•Tetracycline labeling
abnormal
•

27. Clinicalfeatures:
Infants:tetany and convulsions ,failure to thrive deformity of the
skull and thickening of the knees ankle and wrist. enlargement
of costochondral junction.
Childrenwho are already walking usually present with bow legs
or nock knees. Swollen joints and disturbed gait, they also lag
in growth,
In severe cases coxa-vara ,spinal curvature, long bone fractures
Adults (osteomalacia):more insidious course ,patient may
complain of bone ache ,backache ,muscle weakness for many
years before diagnosis is made.

29. x-rays:
active rickets:
thickening and
widening of the
growth plate, cupping
metaphysic, some
times bowing of
diaphysis.

30. Classical lesion of osteomalacia:
Is the looser zones,a thin transverse band of rarefaction
in an other wise normal looking bone.
Especially in the shaft of long bones and the axillary
edges of scapula are due to incomplete stress fractures
which heal with callus lacking calcium
Lateral indentation of acetabula (trefoil pelvis)
Bi concave vertebrae ( from disc pressure).
Spontaneous fracture of the ribs ,pubic rami, femoral
neck.

33. Lab. investigation
Biochemistry:
Diminish level of ca,po4.
Increase alkaline phosphatase.

34. Treatment
Treatment with vitamin D (400–1000 IU
per day and calcium supplements is
usually effective; however, elderly people
often require larger doses of vitamin D(up
to 2000 iuper day
Surgery
Established long-bone deformities may
need bracing or operative correction once
the metabolic
disorder has been treated

35. disease Paget's
(osteitis deformans).

36. disease Paget's
(osteitisdeformans).
Characterized by enlargement and thickening of
the bone ,the internal architecture is abnormal
and bone is usually brittle ,
The condition has ethnic and geographic
distribution
Common in north America. Britain,,,, (more than
3% of people aged over 40).
Rare in Asia.

37. Pathology:
The characteristic cellular changes is a
marked increase in osteoclasts and
osteoblasts activity.
Bone turnover is accelerated.
Plasma alkaline phosphatase is raised sign
of osteoblast activity.
Increase excretion of hydroxyprolinein the
urine sign of osteoclast activity.

38. Clinicalfeatures:
Affects men and women
equally
Appear after age of 50
Pelvis ,tibia is most common
site
Femur , skull, spine is second
most common.
Most cases are
asymptomatic. (x-ray for
other reasons).
And when pt. usually present
because of pain and
deformity, or complications
of the disease.
The pain is dull in nature but
rarely severe unless
fracture occurs or sarcoma
supervene.

39. Clinicalfeatures:
Deformities are seen mainly in the lower limbs
The tibia bows anteriorly and femur anteriolaterally.
If the skull affected is enlarges.
Kyphosisso the patient is shorter and ape like.
Cranial nerve compression may lead to impaired
vision ,facial palsy, deafness…

40. Lab. investigation
Biochemistry:
Serum calcium and phosphorus are normal.
Increased alkaline phosphatase level.

41. X-ray

42. Complications:
Fractures: especially in weight bearing long bones.
Osteoarthritis:
Nerve compression and spinal stenosis
Bone sarcomas: about 1% of cases suspicion if the
previouslybdiseasedbone become more painful,swollen
and tender.
High out put cardiac failure:rare due to increase bone
blood flow.
Hypercalciemia: if the patient immobilized for long

43. Treatment:
Most patients have no symptoms so require no
specific treatment.
If pain appear is mostly due to arthritis and this can
be treated by non steroidal anti inflammatory
drugs.
The indication for specific treatment are:
1-persistent bone pain
2-repeated fracture.
3-neurological complications.
4-high cardiac failure.
5-hypercalciemiadue to immobilization.
6-before and after major surgery ,risk of
hemorrhage.

44. Treatment
Drugsthat suppress bone turn over:
1-biphosphonates.
2-calcitonin.. reduce bone resorption by
decrease activity and numbers of
osteoclasts.
(50-100)MRC unit given s.cdaily until pain
subsides or alkaline phosphatase
decrease.

45. Treatment
Surgery For:
1-pathological fracture.---internal fixation
2-painful osteoarthritis ---partial or total
replacement.
3-nerve compression--------decompression.
4-sarcoma---------resection

46. Thank you