OSTEOPOROSIS

Overview

Osteoporosis, or porous bone disease, is characterized by low bone mass and structural deterioration of bone tissue, resulting in reduced bone strength leading to an increased risk of fracture. The common site for osteoporotic fractures is the hip, spine & wrist.

The World Health Organization (WHO) operationally defines osteoporosis as a bone density that falls 2.5 standard deviations (SD) below the mean for healthy adults of the same age & sex.

 

Epidermilogy

In India, it has been presumed that 35% of postmenopausal women are at the risk of developing osteoporosis.

On average, a post-menopausal woman has a 40% to 50% chance of developing a fracture including a 15% chance of hip fracture in her lifetime. 

More than 10% of hip fracture victims die within one year from various complications and nearly 50% of the survivors are incapacitated, some of them permanently. 

In women, it is 3 times more common than men as they have low peak bone mass (PBM) and hormonal changes at Menopause.

 

Causes & Risk Factor

Although the exact cause of osteoporosis is still unknown, the process by which bone becomes porous is well understood. 

Early in life, bone is broken down and replaced continuously by the process of bone remodeling.

Lifestyle Factors

Low Calcium Intake Alcohol Abuse High Salt Intake Vit. D Insufficiency
Smoking Excess Vit. A Immobilization Inadequate Physical Activity

 

Genetic Factors

Cystic Fibrosis Homocystinuria Osteogenesis Imperfecta Ehlers-Danlos Syndrome
Gaucher’s Disease Ideopathic Hypercalciuria Porphyria Hypophosphatasia
Marfan Syndrome Riley-Day Syndrome Hemochromatosis Panhypopituitarism

Hypogonadal States

Androgen Insensitivity Hyperprolactinemia Athletic Amenorrhea Anorexia Nervosa
Premature Menopause Panhypopituitarism Premature Ovarian Failure Turner’s & Klinefelter’s Syndromes

 

Endocrine Disorders

Adrenal insufficiency Cushing’s Syndrome Diabetes Mellitus
Central Adiposity Hyperparathyroidism Thyrotoxicosis

 

Gastrointestinal Disorders

Celiac Disease Gastric Bypass Primary Biliary Cirrhosis
Inflammatory Bowel Disease Malabsorption GI Surgery

 

Hematological Disorders

Multiple Myeloma Monoclonal Gammopathies Sickle Cell Disease
Hemophilia Leukemia & Lymphomas Thalassemia

 

Rheumatologic & Autoimmune Diseases

Ankylosing Spondylitis Lupus
Rheumatoid Arthritis Other Rheumatologic & Autoimmune Disease

 

Central Nervous System Disorders

Epilepsy Parkinson’s Disease
Spinal Cord Injury Multiple Sclerosis

 

Miscellaneous Conditions & Diseases

HIV/AIDS Congestive Heart Failure Posttransplant Bone Disease Depression
Sarcoidosis Amyloidosis End Stage Renal Disease Weight Loss
Chronic Metabolic Acidosis Hypercalciuria Idiopathic Scoliosis Muscular Dystrophy

 

Medications

Aluminum (in Antacids) Glucocorticoids Tamoxifen Proton Pump Inhibitors
Anticoagulants (heparin) Aromatase Inhibitors Lithium Depo-medroxyprogesterone
Anticonvulsants Barbiturates Chemotherapeutic Drugs Methotrexate

 

SYMPTOMS

Patients with osteoporosis are asymptomatic until a fracture occurs.

But once your bones have been weakened by osteoporosis, you might have signs and symptoms that include

  • Kyphosis with Chronic Pain
  • Gradual Onset of Height Loss
  • A bone that breaks much easier than expected
  • Back pain, caused by a fractured or collapsed vertebra

 

When to see a doctor?

  • Early Menopause
  • Prolonged Corticosteroid Therapy 
  • Either of your parents had hip fractures.

 

Diagnosis

 

Bone Density Testing

A bone density test is as close as your doctor can come to predicting your future bone health. The test results will show if you have osteopenia or osteoporosis, and how susceptible your bones are to fracture. A bone density test is the best way to predict fracture risk.

The test uses X-rays to measure how many grams of calcium and other bone minerals are in a square centimeter of bone. Generally, the higher the mineral content, the denser the bone is. And the denser bones are, the less likely they are to fracture.

Bone density testing uses a device called a bone densitometer. Most densitometers measure how much of a low-energy X-ray beam is absorbed as it passes through bone, in comparison to the absorption as the beam passes through the soft tissues next to the bone. The amount of X-ray energy that enters the bone is also compared with the amount of energy that leaves the bone. Denser bone absorbs more of the X-ray beam.

 

Central Densitometers

These machines, typically found in hospitals and medical centers, are used to measure the density of the central, stabilizing parts of the skeleton, such as the spine and hip. This type of densitometer provides the most accurate bone density testing and can predict your potential risk of fracture.

 

Dual-energy X-ray absorptiometry (DXA) A DXA machine uses two different X-ray beams to increase the precision of what it’s measuring. As you lie on a padded platform, two mechanical arms containing an X-ray source and detector above and below your body are aligned. DXA is most often performed on the narrow neck of the upper leg bone (femur), just below the hip joint, as well as the lumbar vertebrae, which form the lower part of the spine. DXA testing is painless and takes only a few minutes.

Quantitative computerized tomography (QCT) This instrument measures bone density using computerized tomography (CT). Similar to having a CT scan, you lie on a movable padded table that slides into a large cylinder, where X-ray images are obtained from all angles. QCT is most often used to measure density in the vertebrae and the part of the femur below the hip.

Peripheral Densitometers: Smaller devices are used to measure bone density on the periphery of the skeleton, such as in the wrist and heel bone. Although they are more portable, these densitometers are less accurate at predicting fracture risk. If your test on a peripheral device is positive for osteopenia or osteoporosis, then your doctor might recommend a follow-up scan of your spine or hip to confirm the diagnosis.

Quantitative ultrasound (QUS). This procedure is often called heel ultrasound because it typically measures bone density in the heel bone. Instead of X-ray radiation, QUS sends high-frequency sound waves through your heel while you rest your bare foot on the instrument. This type of densitometer measures the reflection of sound waves. Denser bone reflects sound waves back to the device sooner.

Peripheral dual-energy X-ray absorptiometry (pDXA): This device is a compact, portable DXA scanner. Using X-rays, pDXA measures bone density in the wrist or heel. Although it’s quick and accurate, this testing can be expensive.

Peripheral quantitative computerized tomography (pQCT): This portable version of QCT measures the bone density of the wrist or hand. This test is also expensive, and it produces a higher radiation exposure than do other tests.

Other types of testing, including 3-D imaging and high-resolution magnetic resonance imaging (MRI), are also under investigation.

TREATMENT

Treatment is based on the following factors:

  • Age
  • Sex
  • Risk of Breaking a Bone
  • Previous Injury History

If you’ve been diagnosed with osteoporosis because you’ve had a broken bone, you should still receive treatment to try to reduce your risk of further broken bones.

 

Medicines for Osteoporosis

A number of different medicines are used to treat osteoporosis (and sometimes osteopenia).

 

Bisphosphonates

Bisphosphonates slow the rate that bone is broken down in your body. This maintains bone density and reduces your risk of a broken bone.

There are a number of different bisphosphonates, including:

  • Alendronic acid
  • Ibandronic acid
  • Risedronic acid
  • Zoledronic acid

They’re given as a tablet or injection.

Bisphosphonates usually take 6 to 12 months to work, and you may need to take them for 5 years or longer.

You may also be prescribed Calcium and Vitamin D supplements to take at a different time to the bisphosphonate.

 

Side Effects of Bisphosphonates:

  • Gastric Irritation
  • Difficulty in Swallowing
  • Stomachache
  • Osteonecrosis of the Jaw

 

Selective Estrogen Receptor Modulators (SERM)

SERMs are medicines that have a similar effect on bone as the hormone estrogen. They help to maintain bone density and reduce the risk of fracture, particularly of the spine.

Raloxifene is the only type of SERM available for treating osteoporosis. It’s taken as a daily tablet.

 

Side Effects of SERM

  • Hot Flushes
  • Leg Cramps
  • Potential Increased risk of Blood Clots

 

Parathyroid Hormone

Parathyroid hormone treatments (such as teriparatide) are used to stimulate cells that create new bone. They’re given by injection.

 

Side effects of Parathyroid Hormone Therapy

  • Nausea
  • Vomiting

 

Calcium & Vit. D Supplements

Calcium is the main mineral found in bone, and having enough calcium as part of a healthy, balanced diet is important for maintaining healthy bones.

Vitamin D helps the body absorb calcium. All adults should have 10 micrograms of vitamin D a day.

 

Hormone Replacement Therapy

HRT has shown to keep bones strong and reduce the risk of breaking a bone during treatment.

 

Side Effects of Hormone Therapy

Hormone Therapy is not recommended for treating osteoporosis as it increases the risk of developing: 

  • Breast Cancer 
  • Endometrial cancer
  • Ovarian cancer
  • Stroke
  • Venous thromboembolism

 

PREVENTION OF OSTEOPOROSIS & OSTEOPOROTIC FRACTURE

a. Nutrition

  • For all individuals, a well-balanced diet with adequate Calcium & Vitamin D is essential for healthy bone. 
  • Calcium contributor – Dairy products like milk, yogurt, cheese, ice cream, cottage cheese, and fortified orange juice or soy products. 
  • Certain cereals, waffles, snacks, juices, and crackers. Green leafy vegetables and nuts, particularly almonds, are also sources of calcium.
  • Most vitamin D comes from sun-induced skin conversion. 
  • Vitamin D contributors – fatty fish, few unfortified foods. Other nutrients such as salt, high animal protein intake, and caffeine may have modest effects on calcium excretion or absorption. Adequate vitamin K status is required for optimal carboxylation of osteocalcin, so states in which vitamin K nutrition or metabolism is impaired, such as with long-term warfarin therapy, have been associated with reduced bone mass. 
  • Although dark green leafy vegetables such as spinach and kale contain a fair amount of calcium, the high oxalate content reduces the absorption of this calcium (but does not inhibit the absorption of calcium from other food eaten simultaneously). 
  • Magnesium is abundant in foods, and magnesium deficiency is quite rare in the absence of a serious chronic disease. 
  • Magnesium supplementation may be warranted in patients with inflammatory bowel disease, celiac disease, chemotherapy, severe diarrhea, malnutrition, or alcoholism. 

 

b. Life-Style Modifications 

  • Physical activity-weight bearing and muscle strengthening exercises.
  • Cessation of Smoking, Alcohol & High Caffeine Intake.
  • Adequate Sun Exposure

 

c. Prevention of Fall

  • Exercises like balance training, lower limb strengthening exercises.
  • Correction of Low Vision
  • Hearing Impairments
  • Reduce Environmental Hazards
  • Appropriate reduction of Harmful Medicines
  • Education of Individual in Behavior strategies

 

d. Hip Protectors

They prevent impact on the pelvis. The different types of Hip Protectors are: 

  • Energy absorption type 
  • Energy shunting types 
  • Crash helmet type 
  • Airbag type

 

 

ROLE OF ORTHOPAEDICIANS & SURGICAL MANAGEMENT

The goals of surgical treatment of osteoporotic fractures include:

– Rapid Mobilization

– Return to normal Function & Activities

– Avoid too many manipulations

– Progressive Physiotherapy