Q. I’m a T10 complete para, 25 years post-injury. Ten years ago I broke my femur during a simple fall out of my chair. The tumble was not as bad as the big-time falls I used to take playing wheelchair football. My doc ordered a bone scan, which showed no problem in my spine but osteoporosis in my hips, and she put me on Fosomax. I’ve taken it once a week ever since. However, subsequent bone scans don’t show any improvement in my hips.
Lately I’ve read articles suggesting long-term use of drugs like Fosomax can cause serious side effects. Is there information on whether these types of drugs help prevent fracture in people with SCI?
A. Fosomax is the brand name for alendronate sodium, an oral medication in the bisphosphonates family of drugs that are used to treat osteoporosis, a condition in which bones become so porous they fracture easily.
In order to understand how bisphosphonates work, it is important to understand that bones are living tissue. Throughout our lives new bone is growing and replacing old bone that is absorbed by the body. Bone tissue grows faster than it is absorbed, reaching maximum strength and density — known as peak bone mineral density — around age 30. After that, bone absorption slowly outpaces growth. Osteoporosis is bone loss of about 28 percent or more. Biphosphonates help increase BMD by binding to the surfaces of the bones and slowing down bone reabsorption, enabling bone-building cells to catch up.
Like all medications, bisphosphonates have possible side effects, including nausea, heartburn, possible damage to the esophagus, and gastric ulcer. In nondisabled people there have been rare reports of unusual femur fractures and extremely rare reports of osteonecrosis of the jaw — mostly in people with cancer receiving large doses of IV bisphosphonate on a monthly basis.
According to the National Osteo-porosis Foundation, bisphosphonate use reduces fracture risk by an average of about 50 percent among nondisabled people with osteoporosis. This makes taking bisphosphonates seem like a no-brainer. But when it comes to osteoporosis and SCI, it isn’t that simple.
Osteoporosis in nondisabled people — primarily post-menopausal women and older men — is systemic, meaning all bones in the body are affected the same. Osteoporosis caused by SCI, on the other hand, is regionalized in the lower extremities. Bones get thinner from the hip to the knee and thinner still from the knee to the heel, explains Dr. Douglas Garland of Memorial Orthopedic Surgical Group in Long Beach, Calif. He says the average person with SCI loses about 28 percent of BMD in their legs in the first 1.5 years following injury, then continues to lose bone at about 1 percent a year.
There is no evidence that bisphosphonates decrease fractures in people with SCI, says Garland. Also, most studies on SCI and osteoporosis are looking in the wrong place by using standard bone scans that check BMD at the wrist, lower spine and hips. He says a bone scan study is useless unless it is programmed to look at the knee.
Kathleen Dunn, clinical nurse specialist and rehab case manager, agrees. “In the absence of information that bisphosphonates are at all effective in improving density around the knee, and given their potential side effects,” she says, “most experts in the field feel that we should not use them for people with chronic SCI.”
Dunn says her information was reinforced by an excellent presentation she saw at last year’s Academy of Spinal Cord Injury Professionals conference about a 12-month double-blind study of people with acute motor-complete SCI, which is when most bone is lost. The experimental group received a dose of IV zolendronic acid — once-a-year IV bisphosphonate. The results showed that bisphosphonates made no improvement in the areas above and below the knee, those areas most at risk for osteoporotic fractures in people with SCI.
In the meantime your best shot at healthy bones is good nutrition. Garland says you should be getting at least 1,200 mg of calcium and 800 IU of vitamin D per day. Although supplements are better than nothing, ideally it should be real food — because the SCI population has a harder time with absorption, he says.
Nutritionist Joanne Smith, co-author of Eat Well, Live Well with Spinal Cord Injury, suggests eating calcium-rich foods such as green leafy vegetables (watercress, kale, arugula, broccoli), Greek yogurt, cheese, almonds, salmon and sardines (with bones), as well as a high quality calcium citrate supplement that contains nutrients such as magnesium, phosphorous, boron and vitamin D3.
Advice in this column is supported by Craig Hospital’s SCI Nurse Advice Line, a toll-free hotline for people living with SCI, a community service partially funded by the PVA Education Foundation, Craig H. Nielsen Foundation and Caring for Colorado Foundation. For non-emergency nursing info about SCI health, call 800/247-0257 between 9 a.m. and 4 p.m. Mountain time.