Bone Up on Osteoporosis
You can manage some of the risk of developing this degenerative bone disease
By Amie King

People who have complex regional pain syndrome (CRPS) should know about their increased risk for osteoporosis, a condition characterized by decreased bone mass and deterioration of bone tissue. Osteoporosis, which causes bones to become fragile and creates an increased risk for fracture, can be a concern in the dystrophic, ischemic, and atrophic stages of CRPS. Though you cannot consciously control the CRPS disease process, you can influence many of the following factors that increase the risk of developing osteoporosis.

Learned disuse

Many people with CRPS naturally, though mistakenly, avoid movements that hurt. This can lead to a “learned disuse” pattern, which can result in bone loss and decreased tissue strength. A bone needs consistent stress placed upon it to be strong, and that stress occurs with weight bearing or when muscles pull on the bone to create movement. Because these two activities often hurt people with CRPS, many avoid putting weight through their affected extremity, and/or using it in a normal way. For example, you might hold your hand in a guarded fashion, or use an assistive device, such as a cane or crutches. These activities decrease pain at the time, or protect the area; however, if this becomes habitual, the bone will not get the stress it needs to maintain its bone mineral density. As the bone itself weakens, the extremity’s tolerance to the very activities it needs to perform to gain density weakens as well.

The importance of aerobic, weight bearing, and resistance exercises can not be overstated. A therapist will be able to guide you through exercises and activities designed specifically to maintain functional use of your extremity as well as a healthy bone density. The goal is to create an exercise plan that achieves the right amount of stress to the bones and soft tissues of the extremity without overdoing it. A trained therapist will know what activities to initiate. Sometimes just simple active movement is all that is tolerated. This can be beneficial by providing muscular pull against the bone, which causes it to rebuild and become denser. In other circumstances, active range of motion may be contraindicated for a period of time. In these instances, a protocol involving scrubbing and carrying to stress the bone tissue without any joint motion would be better advised. Open communication with the therapists is crucial in determining the right treatment plan. Once an appropriate exercise program is designed, regular, independent completion of that program is vital. Increased activity initially may be uncomfortable, or even “flare up” pain, but consistent diligence with the program will prove valuable over time in function, health, and pain levels.

Nutrition and Lifestyle

Everyone knows “milk does a body good”, and calcium certainly is important in bone health, though there are many other factors at play. A diet rich in calcium, magnesium, vitamin D, zinc, copper, and manganese has been associated with greater bone density.

Additionally, diets too high in sodium or protein can have adverse effects on bone health. It is important to be aware that what you eat can make a substantial difference in many aspects of your health. For more specific information on the role of nutrition, speak to your doctor or a registered dietician.

The Stages of CRPS

CRPS can progress through several stages. Some physicians classify them by stage numbers (ie, first, second, and third stage) and others by the changes in the extremity, or both.

The first (“hyperemic”) stage after injury is marked by increased blood flow and swelling to the area of injury, which may cause the extremity to feel warm and swollen.

The second (“dystrophic” or “ischemic”) stage is characterized by neurovascular changes that affect the blood flow into the extremity, causing it to feel cool.

The third (“atrophic”) stage generally happens around 6 months after the injury and the neurovascular changes have become even more pronounced. A decrease of blood flow into the affected area occurs in addition to other sympathetically-mediated changes. The change in blood flow, along with other nervous system changes, can cause increased risk for developing osteoporosis in an extremity with CRPS.

Amie King is a physical therapist at the The Rehabilitation Institute of Chicago’s Chronic Pain Care Center in Chicago, Illinois.

RSDSA Review. Fall 2006.