Byline: Andrea Salzman, MS, PT
Fast Facts
· In US, between 5–10 million women have been diagnosed as having osteoporosis [1]
· Each year, 1 in 3 community-living adults over the age of 65 years falls. [2, 3]
· In U.S alone, there are 250K hip fractures and 500K spinal fractures, yearly [4]
· 50-70% of women do not recover fully after hip fracture4; as many as 25% will die within the first year post-fracture. [5]
· Exercise contributes to a decreased fracture risk by maintaining or improving bone density and improving balance, leading to a decreased risk of falling. [6]
Historically, aquatic exercise has never been considered as a viable method to combat bone loss. Think about it. Any exercise program designed to retard the rate of bone loss (or increase the rate of bone growth) must consider: the frequency and duration of the activity, the ground reaction forces (GRF) created during the activity, the amount of muscle-bone tension created during the activity, and the patient’s age at the time of activity.
Because immersion can diminish weight bearing forces by more than 90%, aquatic-based exercise has always been seen as a poor substitute for weight-bearing tasks, such as walking. However, this perspective has changed dramatically over the last decade for multiple reasons.
First, individuals who are unable to weight bear easily or comfortably under gravity’s full brunt, can easily do so when immersed to chest-level in water. Second, individuals who choose to not exercise regularly on land, due to pain, fatigue or other factors, may be willing to do so in the water. Third, the study of aquatic plyometrics has shown clinicians that it is possible to execute speed, power and other explosive activities in water; and moreover, that these activities result in similar athletic gains as their land-based counterparts, without the incidence of injury. Lastly, while the argument that exercise in the water will produce less weight-stressors is technically true, this argument ignores all other mechanisms by which the body lays down bone. For example, muscle pull on bone is an excellent stimulus for bone growth. Exercise in the viscous medium of a swimming pool produces drag… and drag produces resistance… and resistance creates muscle pool. End result? More bone.
Overview
Osteoporosis is a systemic disease characterized by a loss in bone mass and an increased fracture risk. In osteoporosis, the skeleton is still capable of laying down bone; in other words, there is no incapacitation of the body’s ability to mineralize. Bone remodeling is a life-long process. However, the aging process creates a perfect storm of factors which make it less likely for the body to retain its bone mass. After menopause, estrogen levels decline which — coupled with a reduction in weight-bearing and muscle-stressing activities — reduces the body’s bone formation capacities.
The World Health Organization has established a standard measurement for osteoporosis by comparing Bone Mass Density (BMD) with young adult women who are at the age of peak bone mass.
Normal bone mass = t score > -1
Osteopenia = t score between -1 and -2.5
Osteoporosis = t score < -2.5 (or >2.5 SD below the young adult mean)
The consequences of osteoporotic fracture include diminished quality of life, decreased functional independence, and increased morbidity and mortality. To prevent or reduce these consequences, therapists need to consider the potential of the pool.
Statements of Medical Necessity
The following language can be used in your documentation to support the medical necessity of aquatic therapy. If you decide on aquatic therapy as a treatment option during the initial evaluation, insert the master statement in the evaluation. After that, you should make the case for continuing to use aquatic therapy on an ongoing basis (daily or weekly). At that time, you may choose to use whichever specific justification statement is appropriate.
Assessment (master statement): PATIENT presents with loss of bone density, history of multiple compression fracture of spine, restricted ROM and loss of functional strength. She has a high fall risk (low Berg score) and has recently fallen 3x at home. She is reliant on an assistive device which alters her postural relationship with the environment. She is in constant pain, unwilling to move freely or try novel balance challenges, and is expressing frustration with her virtual home-bound status.
I choose to perform PATIENT's physical therapy using an aquatic medium in order to capitalize on water's physical properties. These properties include, but are not limited to, buoyancy (used to reduce weight bearing and provide a safe environment for balance challenges), viscosity (for graded progression of strength training and for sensory input), and thermal shifts (for pain control). The pool is an ideal motivating environment as PATIENT can create novel balance challenges without suffering the negative consequences of failing or falling. Over 5 recent studies have demonstrated the benefits of aquatic therapy for this population (see attached).
Assessment (specific impairments):Osteoporosis: By placing PATIENT in the pool, it is possible to increase nutrient delivery to the tissue, maximize the osteogenic effects of exercise and provide early return to movement – all without additional compression fractures or risking a catastrophic fall.
Bone-stimulation needs: In water, PATIENT can be directed to weight-bear in a controlled, graded and progressive manner merely by choosing an appropriate level of immersion. Although pool-based exercise will provide less weight bearing forces than land based exercise, pain and fear will not prevent PATIENT from exercising. This will result in a net overall gain in stimulation to the bone. In addition, movement in water is resisted by water’s viscosity; this resistance will stimulate bone growth by requiring the muscle to pull against the bone.
Dependence in ambulation: PATIENT depends heavily on an assistive device (a front wheeled walker) which is creating abnormal movement patterns and teaching her to rely on an artificially expanded support base. Buoyancy can reduce PATIENT's weight by over 75% allowing her the opportunity to re-learn normal movement engrams, without support from her upper extremities. Additionally, the water's refraction makes it difficult to trust vision for proper foot placement, requiring PATIENT to develop kinesthetic awareness of where the body is in space.
Compromised balance: PATIENT's fragile bones and compromised balance places her at risk for falls and learned immobility. In the pool, buoyancy provides a safe environment in which to attempt new movements (a necessary component of learning) and to fail without catastrophic consequences (which increases the willingness to try). Additionally, the viscosity of the water allows for increased processing time and ability to right the body, which aids in PATIENT’s ability to generalize and produce the needed corrections on land.
Poor endurance: PATIENT has learned to fear standing which means she now fatigues quickly and is unable to complete repetitions of motor sequences. The properties of the water can be manipulated to produce lowered resistance so PATIENT can practice gross motor skills without fatiguing. This may facilitate higher motor learning such as bilateral coordination and motor planning.
Restrictions in ROM: PATIENT’s limbs are easier to move against gravity during immersion as they lose most of their weight in water. PATIENT can also be positioned properly in water in order to provide a low friction surface for movement, encouraging spontaneous active ROM with less effort than when restricted by gravity. Additionally, the water can provide the “ultimate treatment plinth” – allowing a skilled therapist ease of positioning and access for stretching and joint mobilization.
Weakness: Water immersion provides a resistive medium that can be manipulated by a skilled therapist to either assist or resist movement. During early rehab, the immersed limb is automatically supported by buoyancy, which will assist PATIENT in moving her body against gravity. As rehab progresses, movements can be accelerated to create more drag. Such activities can be structured to create more effort than the identical movements on land.
Pain: Post-fracture pain decreases PATIENT's willingness to move and weight bear, both necessary for healing. During immersion, the properties of buoyancy, viscosity, hydrostatic pressure and thermal shifts couple to create an environment where activities are less painful than their land-based counterparts. This new movement freedom helps interrupt the pain cycle.
Therapists looking to support these contentions with published, referred articles do not have far to look. [7-20] While it is true that immersion can diminish weight bearing forces by more than 90%, aquatic-based exercise is no longer considered a non-starter when working with patients with bone loss. In fact, you might say it has come full circle; aquatic exercise has finally achieved the “gravity” it deserves.
References
Looker AC, Johnston GC, Wahner HW, et al: Prevalence of low femoral density in older US women from NHANES III. J Bone Miner Res. 1995;10:796–802
American Geriatrics Society, British Geriatrics Society, American Academy of Orthopaedic Surgeons. Guideline for the prevention of falls in older persons. American Geriatrics Society, British Geriatrics Society, and American Academy of Orthopaedic Surgeons Panel on Falls Prevention. J Am Geriatr Soc. 2001;49:664–72.
Kanis JA, McCloskey EV. Evaluation of the risk of hip fracture. Bone. 1996;18(suppl.):127–32S.
Prestwood, K.M., Gustavo, D. Osteoporosis in Older Women. In: Encyclopedia of Endocrine Diseases, Volume 3. 2004 Elsevier Inc.
Health Quality Council. Saskatchewan seniors experiencing hip fracture: characteristics and health outcomes. Summary report.. Saskatoon: The Council; 2003.
Brown J, Josse R. Scientific Advisory Council of the Osteoporosis Society of Canada. 2002 clinical practice guidelines for the diagnosis and management of osteoporosis in Canada. CMAJ. 2002; 167(10 suppl.):S1–34.
Arnold CM, Busch AJ, Schachter CL, Harrison EL, Olszynski WP. A Randomized Clinical Trial of Aquatic versus Land Exercise to Improve Balance, Function, and Quality of Life in Older Women with Osteoporosis. Physiother Can. 2008 Fall;60(4):296-306.
Ay A, Yurtkuran M. Influence of aquatic and weight-bearing exercises on quantitative ultrasound variables in postmenopausal women. Am J Phys Med Rehabil. 2005 Jan;84(1):52-61.
Ay A, Yurtkuran M. Evaluation of hormonal response and ultrasonic changes in the heel bone by aquatic exercise in sedentary postmenopausal women. Am J Phys Med Rehabil. 2003 Dec;82(12):942-9.
Bravo G, Gauthier P, Roy PM, Payette H, Gaulin P. A weight-bearing, water-based exercise program for osteopenic women: its impact on bone, functional fitness, and well-being. Arch Phys Med Rehabil. 1997 Dec;78(12):1375-80.
Cerveira F et al. Effects of High Intensity Aquatic Exercises on Bone Mineral Density in Postmenopausal Women with and without Vertebral Fractures. American Journal of Sports Science. 2013; 1(1): 1-6.
Devereux K, Robertson D, Briffa NK. Effects of a water-based program on women 65 years and over: a randomised controlled trial. Aust J Physiother. 2005;51(2):102-8.
Gannotti ME, Nahorniak M, Gorton GE 3rd, Sciascia K, Sueltenfuss M, Synder M, Zaniewski A. Can exercise influence low bone mineral density in children with juvenile rheumatoid arthritis? Pediatr Phys Ther. 2007 Summer;19(2):128-39.
Colado JC, Triplett NT, Tella V, Saucedo P, Abellán J. Effects of aquatic resistance training on health and fitness in postmenopausal women. Eur J Appl Physiol. 2009 May;106(1):113-22. Epub 2009 Feb 10.
Harush, Mushi. The effects of water exercise on bone density among postmenopausal women. Unpublished Master’s Thesis. University of Haifa. December, 2004
Littrell, Tayna, Snow, Christine. Bone density and physical function in postmenopausal women after a 12-month water exercise intervention. Unpublished abstract.
Rotstein A, Harush M, Vaisman N. The effect of a water exercise program on bone density of postmenopausal women. J Sports Med Phys Fitness. 2008 Sep;48(3):352-9.
Tolomio S, Lalli A, Travain G, Zaccaria M. [Effects of a combined weight-bearing and non-weight-bearing ( warm water) exercise program on bone mass and quality in postmenopausal women with low bone-mineral density]. [Italian] Clin Ter. 2009;160(2):105-9.
Tolomio S, Ermolao A, Lalli A, Zaccaria M. The effect of a multicomponent dual-modality exercise program targeting osteoporosis on bone health status and physical function capacity of postmenopausal women. J Women Aging. 2010 Oct;22(4):241-54.
Tsukahara N, Toda A, Goto J, Ezawa I. Cross-sectional and longitudinal studies on the effect of water exercise in controlling bone loss in Japanese postmenopausal women. J Nutr Sci Vitaminol (Tokyo). 1994 Feb;40(1):37-47.
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