Osteoporosis

Dr.Rahul kapoor

MBBS, 2nd yr. ortho

Defination

• Osteoporosis is a systemic disorder of the skeleton characterized by low total skeletal bone mass and microarchitectural deterioration of bone tissue with a consiquent increase in bone fragility and susceptibility to fracture .

Acknowledgement

• Most common metabolic bone disease

• 3x more common in women than men

• Fewer than 1/3rd cases are diagnosed

• Only 1/7th receive treatment

• Hip # have 20% mortality in first yr.

• 50% of women(>65yr) have spinal compression # and 2/3rd unrecognised

• Multifactorial origin

• Classified as :- primary :- type I & type II

secondary

• other :- involutional , post-climacteric and idiopathip transient osteoporosis of the hip

• Type I :- result of estrogen loss

increased osteoclastic bone resorption

• Type II :- slow progressive decline in osteoblasticactivity with ageing

• Unfortunately the elderly female often suffers the effect of both

Risk factors

• h/o # in adults ( >40 yrs.)• Low body weight ( < 127 lbs)• Smoking • Alcohol (> 60 ml)• Corticosteroid therapy ( >3 months)• Impaired vision • Early Estrogen deficiency (<45yr)• Prolonged premenopausal amenorrhoea(>1yr)• Low physical activity• Low calcium intake • dementia

Secondary osteoporosis

• Affect any age group

• Men and women equally affected

• Results from chronic medical conditions & prolong use of medication

causes

• Drugs :-

Steroids

Heparin

Anticonvulsant

Cytotoxins

Lithium

Aluminium

cytotoxins

• Malignancy :-

Multiple myeloma

Leukemia

Lymphoma

• Disuse prolonged immobilization

• Endocrine diseases:-

Diabetes

Thyroid disease

Cushing syndrome

Hyperparathyroidism

Exercise induced amenorrhea

Eating disorders

• Gastrointestinal disorders:-

Gastrectomy

Malabsorption syndrome

Liver diseases

Inflammatory conditions

sprue

Clinical features

• Asymptomatic silent bone changes

• Spontaneous vertebral fractures

• Acute or chronic back ache

• Loss of height

• Protuberant abdomen

• dowager’s hump

• Oral alveolar bone loss

WHO

• The world health organization has estblished an operational definition depending on BMD, commonly expressed as T- score.

• A T – score of atleast - 2.5 SD and below the young adult mean

• A T score represents a pateints bone density expressed as the number of SD above or below the mean BMD value of normal young adult

BMD

• Proxy to measure bone strength

• Predicts the risk of fracture

• Expressed as SD in T AND Z score

• 50%-100% increase in fracture risk for each SD decline in bone density

• DEXA is the standard for measuring BMD

• 3 Sites

1) Radius distal end

2) Hip

3) Spine

Others

• CT - trabecular bone ,expensive

• ULTRASOUND – inexpensive

• X-RAY - 30% - 40% of bone loss

• MRI -

Laboratory Assessment

1) CBC count

2) Serum chemistry :-

3) urinary calcium excretion

Additional

1. Serum thyrotropin

2. ESR

3. Serum PTH

4. Serum 25-hydroxyvitamin D concentration

5. Urinary free cortisol

6. Serum electrolyte

7. Serum or unine protein electrophoresis

8. Bone marrow biopsy or aspiration

9. Biochemical markers of bone turnover

Biochemical markers

• Assessing fracture risk in elderly

• Therapeutic response to antiresorptive agents

• Identifying patients with high bone turnover

Prevention goals

1) Optimize skeletal development in the young

2) Maximize peak bone mass at skeletal maturity

3) Prevent bone loss (age , secondary causes)

4) Preserve the structural integrity of skeleton

5) Prevent fractures

Preventive measures

• Adequate calcium diet

• Good general nutrition

• Adequate vitamin D intake

• Regular weight bearing exercise

• Avoiding tobacco and caffeine

Additional measures

• Pharmacological agents to pevent bone loss

• Bisphosphonate for all on prednisolone > 3 mths

• Periodic monitoring of thyroid function

• Identification and treatment of conditions that predispose to low peak bone mass

• Identification of patients predisposed to fall

Goals of treatment

1) Preventing fractures

2) Increase in bone mass

3) Relieving symptoms of fracture

4) Maximizing physical function

Candidates for treatment

• Women with T-score -1.5 with at least one risk factor

• Women with ineffective nonpharmacologicalmeasures

• Postmenopausal osteoporosis

• Men with hypogonadism

Management

• Pharmacological measures

• Hormone treatment

• SERMs

• Surgical

Pharmacology options

• Calcium supplements

• Bisphosphonates

• Raloxifine

• Salmon calcitonin

• Teriparatide

Calcium supplements

• Recommended intake is 1500mg/day

• Safe upper limit is 2500mg/day

• Judicialy used in kidney stones pt.

• S/E :- flatulence and constipation

• Eg. Calcium carbonate ,

• calcium citrate ,

• calcium phosphate

Vitamin D

• 200 IU for young adults < 50 yrs.

• 400 IU for 50 – 70 yrs.

• 600 IU for > 70 yrs.

• Higher doses in malabsorption syndrome

• Safe upper limit :- 2000 IU

Bisphosphonates

• Synthetic analogs of pyrophosphate

• Natural inhibitor of bone resorption

• Use :- prevention (35mg/week)

• treatment (70mg/week)

• steroid induced osteoporosis

• Weekly administration reduce side effects

• Duration :- alendronate (< 7yrs.)

• risendronate (< 3yrs.) 35mg/week

• zoledronate (5mg/yr ) iv

• idanbronate ( 150mg/month)

Calcitonin

• Hormone secreted by thyroid gland

• Diminishes bone resorption

• Useful when hormones and bisphosphonates are contraindicated

• Recombinant salmon calcitonin more potent

• Route :- injection or nasal spray

• Dose :- 200 IU/day by spray

• 50 – 100 IU/day im or sc

Teriparatide

• Recombinant human PTH

• Directly stimulates osteoblasts to form new bone

• Dose :- 20 mcg/day sc for max. 2 yrs

• S/E :- osteosarcoma

• Contraindicated :- hypercalcemia , pagets ds., open epiphysis ,

Hormone treatment

• Estradiol level of 40-60 pg/ml

• Best if started 5 – 10 yrs. after menopause

• Comnbination with progestins

• S/E :- Myocardial infarction , stroke , breast cancer

venous thromboimbolism , dementia

• Reduction in colon cancer

SERMs

• Raloxifene , a potent teratogen

• No effect on endometrium

• Benefits :- reduce incidence of breast cancer,

lowers LDL , cholesterol

• S/E :- deep vein thrombosis ,

pulmonary embolism

Combined therapy

• Calcium + vitamin D

• Teriparatide + bisphosphonate

• Testosterone replacements in hypogonadism

SURGERY

• ORIF with pins and plates

• Hemi- arthroplasty

• Arthroplasties

• Vertebroplasty / kyphoplasty

Follow up

• DEXA is done at least 1 yr. apart

• Post- menopausal screening @ yr.

• Pt. on prevention programme every yr.

• Pts. with normal BMD every 2yrs.

•

• Thank you

• Have a nice day

• bye –bye