As the population ages and becomes more sedentary, we will be seeing more of our patients affected by osteoporosis and its complications. Initially, there is a reduction in bone mass (osteopenia), which is considered a universal phenomenon of aging. However, when the condition progresses to osteoporosis, bone strength is compromised, and fractures develop with trivial (or no) trauma. These fractures may affect the extremities, the hip, and the spine. Physical activity and exercise have been shown to provide significant protection from osteoporosis1 and fractures.2 We have a duty to identify those patients who are at risk of fracture, and to provide exercise recommendations that will decrease that risk. We can tailor exercise programs to prevent the spinal complications of osteoporosis, such as kyphosis, vertebral wedging, and compression fractures.
Benefits of Exercise to Bone
As recalled from the principle known as Wolff’s Law, bone density and strength are a function of the magnitude and direction of the mechanical stresses that act on bone.3 Assuming the availability of necessary nutrients, stimulus to the osteoblasts results in a net gain in bone mass. Exercise is a form of repetitive loading that facilitates osteoblastic activity, thereby helping to maintain a positive balance between bone formation and bone resorption.4 Even a moderate amount of exercise that is recommended for general wellness (a minimum of thirty minutes on most days) is helpful in preventing osteoporosis.5
Exercise Types
Aerobic/endurance. Walking and swimming are two of the most commonly recommended forms of exercise for the elderly. While improved aerobic capacity is generally beneficial for most older patients, we mustn’t expect any skeletal improvement. Bone mineral density can be increased by walking, but only when it is done above the anaerobic threshold.6 It is unlikely that most older women, especially sedentary women, will be willing to walk at this intensity. As for swimming, there is no significant difference in bone mass between women participating in a regular swimming program and women who don’t swim.7 This is also true of a standard weightbearing, water-based exercise program (aquacise).8
Impact/weightbearing. In order to create sufficient stimulus to increase bone density, exercise needs to be weightbearing and have some impact. This can be as simple as step-training (ten minutes stepping up and down from an eight-inch high step).1 Use caution when recommending impact exercise to elderly patients.
All exercises are more effective when done in an upright, weight-bearing position, since the entire body is in a closed-chain position during training. The stabilizing muscles, the co-contractors, and the antagonist muscles all learn to coordinate with the major movers during movements that are performed during closed chain exercising. This makes these types of exercises very valuable for the elderly—not just for increasing bone density, but also for preventing stumbles and falls.
Resistance/strength. High-intensity resistance training has been found to be safe and quite effective in increasing strength and function in the elderly.9 Older patients make similar relative, but smaller absolute, strength gains when compared with younger adults. Weight training in a submaximal controlled, supervised situation can also preserve10 and even increase11 bone deposition. Strength training recommendations should be an integral part of chiropractic treatment for older and osteoporotic patients. Exercise tubing is an excellent tool for strength training of the elderly, since the risks of injury are minimized, and a spotter or expensive equipment is not needed.
Spinal Osteoporosis
Spinal X-rays often reveal osteopenia and osteoporosis. By the time changes are visible on X-ray, however, substantial bone loss has already occurred. The most common fractures due to osteoporosis are vertebral fractures, and yet less than a third u u of all vertebral fractures are clinically diagnosed.12 These skeletal of all vertebral fractures are clinically diagnosed.12 These skeletal changes can have a significant impact on posture and our ability to handle subluxation complexes. Specific rehabilitative exercises should be recommended to relieve the postural strain on the spine and to prevent further wedging and compression fractures. Avoiding exercise is the worst approach for an aging patient with osteoporosis. Back strengthening exercise constitutes a powerful intervention for reducing pain and increasing functional capacity.
A warning: Some of the commonly used back exercises may contribute to increased symptoms. For patients with spinal osteoporosis, harmful activity places an anterior load on the vertebral bodies. Patient education must emphasize the dangers of lifting in flexion, and of, possibly, flexion exercises. In fact, one exercise study13 found an increase in new vertebral deformities when postmenopausal women performed flexion exercises (such as forward stretches and abdominal curls), while those who performed only spinal extension exercises had a significant reduction in the number of vertebral compressions.
Corrective Spinal Exercises
Spinal osteoporosis is often associated with poor postural support, specifically an increase in the thoracic kyphosis. This posture is secondary to many decades of flexed activities, and may be compounded by poor posture habits and tendencies to slump. One important factor in chiropractic care is to correct any loss of the normal upright alignment of the pelvis and spine. In addition to general strengthening and coordination exercises, all patients (especially the elderly) should be given corrective exercises that are specific for the postural imbalances they have developed.
Conclusion
A well-designed exercise program can improve posture, help to reduce bone loss, and prevent fractures, while also reducing symptoms. Exercises performed with the spine upright (standing or sitting) can specifically train and condition all the involved structures to work together smoothly. The end result is an effective rehab component for osteoporosis and aging patients who will make a rapid response to their chiropractic care.
Kim D. Christensen, DC, CCSP, CSCS, DACRB, founded the SportsMedicine & Rehab Clinics of Washington. He is a popular speaker, and participates as a team physician and consultant to high school and university athletic programs. Dr. Christensen is currently a postgraduate faculty member of numerous chiropractic colleges and is the president of the American Chiropractic Association (ACA) Rehab Council. He is a “Certified Strength and Conditioning Specialist,” certified by the National Strength and Conditioning Association. Dr. Christensen is the author of numerous publications and texts on musculoskeletal rehabilitation and nutrition. He can be reached at Chiropractic Rehabilitation Assoc., 18604 NW 64th Avenue, Ridgefield, WA 98642 or by email at [email protected].
References
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5. US Dept. of Health and Human Services. Physical Activity and Health: A Report of the Surgeon General. Atlanta: 1996.
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12. Ross PD. Clinical consequences of vertebral fractures. Am J Med. 1997; 103:30S-43S.
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