Your Bone Health
Ninety-eight per cent of men and women with a spinal cord injury (SCI) will lose some bone mass after their injury, placing them at risk of developing osteoporosis.
The information presented here will help you understand:
- what osteoporosis is
- how osteoporosis affects someone living with a SCI
- common risk factors for osteoporosis
- how to find out if you have osteoporosis
- how to prevent osteoporosis
- some available treatments, and
- where to get information about osteoporosis
What is osteoporosis?
Osteoporosis is a bone disease in which bone mass and strength decline, leaving bones fragile and more apt to break.
- Most people will not discover they have osteoporosis until after they break a bone.
- Although osteoporosis most commonly affects women over the age of 50, the disease can develop in men and women with a spinal cord injury at any age.
- People with a SCI who need a wheelchair to get around are at greatest risk for breaking their legs due to osteoporosis.
- However, individuals with a spinal cord injury who walk may also develop osteoporosis and be at risk for breaking their legs.
How does bone develop?
During childhood and into adulthood, your body builds bone. As a result, your bones become thick and dense.
- For women, peak bone mass is reached at about age 20; for men, age 25.
- Starting at about the age of 40, women and men slowly begin to lost bone mass as part of the aging process.
- By the time you are 70 years old, your bones will have lost about one-third of their density.
Your body continually builds and breaks down bone through a process called bone remodeling. This process has two phases: resorption and formation.
- This ongoing cycle of removing old bone (resorption) and replacing it with new bone (formation) is what keeps your bones health and strong throughout your lifetime.
- As long as your body completely replaces the bone it removes, your bone strength remains unchanged.
- When old bone is removed faster than new bone is made, bones become less dense.
Healthy bone is thick and dense with a solid structure, while osteoporotic bone is weak in structure and can break more easily.
What happens to my bones after spinal cord injury?
Most men and women with a SCI will lose up to 30% of their bone mass within the first year of their injury. The degree of bone mass loss varies with the duration and severity of the spinal cord injury.
Most people with a SCI develop low bone density of their hips, knees and ankles.
- Those who develop osteoporosis are at an increased risk of breaking their legs.
- The risk increases the longer you live with your injury.
- Most fractures occur 10 or more years after injury.
What are the most common causes of fractures after spinal cord injury?
The most common causes of fracture after a spinal cord injury are rolling in bed or transferring from your wheelchair into a car. Planting your feet and turning your hips can create enough stress on your knees to cause a fracture.
This picture shows the three most common fracture sites for people who develop osteoporosis after spinal cord injury:
- the thighbone just above the knee
- the shinbone just below the knee, and
- the middle of the thighbone.
Why should I care about fractures?
Living with a spinal cord injury can be challenging. Routine tasks like bathing and getting dressed can take a lot of time and use up a lot of your energy. Breaking your leg will only increase the challenges that you face every day.
- Most fractures take 3 to 6 months to heal.
- If you are normally independent, you may have to reply on the assistance of personal support workers while your fracture heals.
- A fracture may prevent you from working, driving or participating in leisure activities.
- Your limited activity may lead to deconditioning.
- You may also develop a pressure sore from the cast.
How can I tell if I have osteoporosis?
Osteoporosis is often called “the silent thief” because loss of bone density occurs without symptoms. Most people do not know that they have osteoporosis until after they break a bone. Knowing your risk factors and undergoing a bone density test are the keys to diagnosing osteoporosis.
A bone density test can determine whether or not you have osteoporosis. Like any other diagnostic test, a doctor must refer you for a bone density test. This test is safe, painless and takes about 45 minutes to complete.
During the test, you lie on a padded table while the machine scans your lower back, hips and knees. The area where we expect the greatest loss of bone mass to occur in people with a SCI is the knee.
- The bone density test provides a reading of how dense your bones are compared to the peak bone mass of young people of the same gender.
- A t-score of less than -2.5 indicates that you have osteoporosis.
- Results will also tell your doctor if your treatments are working and how likely you are to develop a fracture in the next 10 years.
If you have a SCI, you should have a bone density test every year, whether or not you have been diagnosed with osteoporosis.
What can I do to reduce the risk of developing osteoporosis?
There are many risk factors that play a role in the development of osteoporosis. You can change some factors, but not others.
Check the following risk factors to see which you have. Risk factors in teal are the most common in people with spinal cord injuries.
Risk factors you cannot change:
- spinal cord injury
- wheelchair mobility
- a prior fragility fracture
- family history of osteoporosis or a family member with a hip or wrist fracture
- Caucasian or Eurasian ancestry
- post menopause (women)
- gender—women are at greater risk of developing osteoporosis
- low testosterone (men only)
- long-term (more than 3 months) use of prednisone
- hyperthyroidism
- parathyroid disease
- Celiac disease or Crohn’s disease
- rheumatoid arthritis
- prolonged use of anti-seizure medications
- removal of the ovaries without hormone therapy
Risk factors that are preventable:
- a diet low in calcium
- body weight less than 57 kg or 125 lbs
- low vitamin D3
- lack of weight-bearing exercise
- smoking
- drinking too much caffeine (more than three 8-ounce servings a day of coffee, tea or cola)
- drinking too much alcohol (more than two 2 drinks a day)
- a diet high in salt
The more risk factors you have, the greater your chances of developing osteoporosis. If you have at least 4 risk factors, you are at high risk for osteoporosis.
What can I do to reduce my risk of developing osteoporosis?
Follow these 9 steps to prevent or reduce your risk of developing osteoporosis:
1. Eat a well-balanced died with calcium-rich foods.
Calcium is a mineral important to the formation of strong healthy bones. Ninety-nine per cent of the calcium in your body is in your bones. Calcium also keeps your heart, nerves and muscles healthy. If your body does not absorb enough calcium from the foods you eat, your body will take the calcium from your bones in order to get the amount it needs, resulting in loss of bone mass.
Toronto Rehab recommends a calcium intake of 1000 mg daily after spinal cord injury.
| Common Foods |
Portion |
Calcium Content |
| Milk: 2%, 1%, Skim, Chocolate |
1 cup / 250 ml |
300 mg |
| Cheddar, Edam or Gouda cheese |
1 3/4 inch / 3 cm cube |
245 mg |
| Yogurt - plain |
3/4 cup / 185 ml |
295 mg |
| Canned salmon with bones |
1/2 can / 105 grams |
240 mg |
| Fortified orange juice, rice and soy beverage |
1 cup / 250 ml |
300 mg |
If you find it hard to eat the recommended amounts of calcium-rich foods, your doctor may recommend a calcium supplement. Too much calcium can cause constipation, bladder stones or kidney stones. Talk to your doctor, pharmacist or dietitian about your calcium intake.
2. Get enough vitamin D3.
Vitamin D3 helps your body absorb calcium from the foods that you eat. Your body can produce vitamin D3 by being out in the sun, but often this is not enough. If you do not get enough vitamin D3, you can lost bone mass because your body is unable to absorb all of the calcium that it needs.
Toronto Rehab recommends a daily vitamin D3 intake of 800 IUs (international units) daily during the winter months and 400 IUs daily during the summer months for those under the age of 50. For those over the age of 50, Toronto Rehab recommends a daily vitamin D3 intake of 800 IUs.
- Milk fortified with vitamin D3 contains 100 IUs per 250 ml glass.
- Vitamin D3 is only found in a few foods—margarine, eggs, chicken livers, salmon, sardines, herring, mackerel, swordfish and fish oils (halibut and cod liver oils) contain small amounts of vitamin D3.
Since it is hard to get enough vitamin D3 from food alone, you may need to take a supplement. Too much vitamin D3 can cause heterotopic ossification—the development of bone in soft tissues around a joint, usually the hip. Talk to your doctor, pharmacist or dietitian about vitamin D3.
3. Decrease your alcohol consumption.
Alcohol consumption should be limited to a maximum of two drinks a day.
4. Decrease your caffeine consumption.
Caffeine consumption should be limited to three 8-ounce servings a day. This includes coffee, tea, hot chocolate and cola. Caffeine increases the amount of calcium excreted in your urine, resulting in your body absorbing less calcium.
5. Stop smoking.
Nicotine harms bone-building cells.
6. Exercise regularly.
An active lifestyle is an important factor in maintaining bone health. Weight-bearing and resistance exercises are the most beneficial for preventing and treating osteoporosis.
Weight-bearing exercises are those that involve your bones and muscles working against the force of gravity. These include:
- Standing
- walking
- dancing, and
- horseback riding
Resistance exercises involve moving objects or your own weight to create resistance. This may be done through the use of:
- hand-held weights
- weight-training machines
- exercise bands
- biking
- seated aerobics
- swimming, or
- other wheelchair sports
7. Talk to your doctor
A number of prescription medications are used to treat osteoporosis. The primary aim of these medications is to maintain bone mass and reduce your risk of fragility fracture.
- Bisphosphonates are prescription medications that attach to the surface of the bones and slow down the activity of cells that break down bone. This allows the bone-building cells to work more effectively. Bisphosphonates are available in a daily or weekly pill, or intravenous form.
- Calcitonin is a hormone found naturally in our bodies. Calcitonin slows down the cells that break down bone, allowing bone-building cells to work more effectively. A manufactured form of calcitonin is available by needle or nasal spray.
- Parathyroid Hormone (PTH) increases the activity of bone-building cells. This activation generates new bone faster than old bone is broken down. A manufactured form of PTH is available through injection.
Speak to your doctor to assess the risks and benefits of each treatment option before choosing the best treatment for you.
No matter what therapy you choose, remember that a healthy lifestyle and a diet rich in calcium and vitamin D3 are required to maintain healthy bones.
8. Check your hormone status.
For women only:
- Estrogen helps to build and maintain bone density. During menopause, a woman’s estrogen level decreases and leads to a loss in bone mass.
- Selective estrogen receptor modulators (SERMs) are a family of non-hormonal prescription medications that act like the hormone estrogen in some parts of the body, such as the bones and heart. They come in pill form.
- Hormone replacement therapy (HRT) can be used to help supplement the hormones estrogen and/or progesterone to the lowest level required to prevent bone loss. HRT medications are available in a pill, cream or patch form.
- Many young women will miss their period or have irregular periods for the first year after spinal cord injury. If you are a premenopausal woman and have not had a blood clot, your doctor may prescribe a birth control pill to help make your bones stronger and more dense.
For men only:
- Testosterone helps to build and maintain bone density in men. Testosterone levels can drop gradually in men as they age.
- Low levels of male hormones or hypogonadism can put men at risk of osteoporosis at any age.
- Androgen replacement in men improves sexual function, mood and bone mass, and decreases body fat.
- Testosterone replacement medications are available in a gel, pill or patch.
Learn more about Osteoporosis
Where Can I Get a Bone Density Test?
Wheelchair accessible bone density tests for people with spinal cord injuries or other neurologic impairments are available at:
Toronto Rehab
Lyndhurst Centre
520 Sutherland Drive, Toronto, Ontario M4G 3V9
Bone Density Lab
Phone: 416-597-3422, ext. 6357
Fax: 416-422-1981
Hamilton Health Sciences, Chedoke Site, Wilcox Building
555 Sanatorium Road
Hamilton, Ontario L9C 1C4
Phone: 905-521-2100, ext. 77484
Fax: 905-521-2621
If you know of other centres where wheelchair accessible bone desnity tests are available please contact our web editor.