Falls are the leading cause of injury deaths, as well as the most common cause of nonfatal injuries for older adults in the United States.1 The direct medical costs for nonfatal fall injuries totaled $19 billion in 2000.2 By 2020, the expected cost of fall‐related injuries in those over the age of 65 are projected to be more than $43.8 billion.3 At least one‐third to one‐half of those aged 65 and older will fall each year; incidence increases in frequency and severity for those over age 75.4–6 Many older adults hospitalized following a fall are discharged to long‐term care facilities; falls account for 40% of all nursing home admissions. 7,8 For individuals who reside in nursing homes, the annual fall rate is 50% to 66%, as compared to those in the community, at 33% to 50%.9 According to Bueno‐Cavanillas et al,10 35.5% of falls in nursing homes can be attributed to intrinsic factors (eg, dizziness), 52.1% to extrinsic factors (eg, slipping on a wet surface), while in 12.4% of falls the cause is unknown.
Over the past 2 decades, research has explored the relationship between balance control and motor or sensory system function in order to understand the intrinsic causes of falling and to create effective strategies to prevent falls.11 Many of the intrinsic causes of falling have greater prevalence among aging adults. These age‐related changes in visual, somatosensory, and vestibular systems are well documented.11 As one ages, visual detection and reactive responses tend to become less efficient, potentially altering efficacy associated with dynamic balance.12 Older adults do not always effectively interpret misleading sensory cues or recognize and reintegrate accurate proprioceptive information.13 The net effect of these changes is often less efficient postural control and instability.14 Age‐related dysfunction of the vestibular system sometimes manifests itself as abnormalities in posture, balance, and visual acuity or a combination of these problems.12 Regardless of the source of dysfunction, whether it is visual, vestibular, or somatosensory or a combination, there is an increased risk of falling.
According to the Guide to Physical Therapist Practice (2nd ed.), physical therapists examine, evaluate, and provide risk reduction and primary prevention interventions for individuals with loss of balance and history of falling.15 Physical therapy interventions designed to reduce falls in the elderly typically include 3 major components: strength, balance, and endurance.16 The Cochrane Collaboration conducted a systematic review of fall prevention studies that incorporated exercise programs such as progressive muscle strengthening, balance training, and an ambulation plan. Pooled data from these studies indicate that such programs significantly decreased the number of individuals experiencing a fall.17 Although the use of a pre‐planned or established strengthening, balance, and gait training regime to restore balance to reduce fall occurrence is supported by research findings, few studies have examined interactive dynamic balance activities/exercises in the elderly as an intervention to improve postural control and reduce fall risk. Although exercise in general appears to have statistically significant beneficial effect on balance,18 the superiority of one form of balance exercise over another has yet to be determined.16
Several types of balance exercises and devices have been developed, including manual, mechanical, and computerized. Virtual reality (VR) has been used since the mid‐1990s, as one means to enhance balance in persons at risk of falling.19 Virtual reality is a computerized system that simulates an activity or experience.20 A set of head mounted display goggles, connected to a computer simulating the subject in a virtual indoor or outdoor environment during ambulation is such an example. Flynn et al21 explored the use of a VR device for an individual in the chronic phase of stroke recovery and demonstrated clinically meaningful improvement in the Dynamic Gait Index, and trends toward improvement in the Berg Balance Scale. Under certain conditions and with specific tasks, stronger outcomes have been demonstrated with training in virtual versus physical environments.
Some VR training environments have been enhanced by the addition of video games, increasing patients' motivation and enjoyment. 20–22 Betker et al20 determined that a video game‐based exercise regimen motivated subjects to increase their practice volume and attention span during training. They noted that this, in turn, improved their subjects' dynamic balance control.20 Tamura et al23 developed a low‐cost personal computer‐based rehabilitation tool used to assist older adult subjects maintain balance and muscle strength, and found that the video‐based game had a positive effect on static and dynamic balance in older adult subjects. Although there is evidence of effectiveness of virtual reality and, more specifically, the use of video games in enhancing static and dynamic balance, there has been little research on the efficacy of the Nintendo Wii (Nintendo of America Inc., Redmond, WA) in the treatment of balance dysfunction. The purpose of this case report is to describe clinical outcomes following use of the interactive Wii bowling simulation with an elderly nursing home patient diagnosed with an unspecified balance disorder.
The patient was an 89‐year‐old female (height 162.6 cm; weight 67.9 kg; BMI 26) who had resided in a skilled nursing (SNF) facility for 22 months. She was initially admitted from the hospital with failure to thrive after several non‐injurious falls at home. Upon long‐term admission to the SNF, she received physical therapy 5 times per week, once a day, for 3 weeks. Interventions consisted of therapeutic exercise, neuro‐muscular re‐education, therapeutic activities, including balance training and gait training. Balance training included single and double‐lower extremity stance activities with eyes open and closed and navigating over and around obstacles. At time of discharge from physical therapy she ambulated independently within the facility without an assistive device for up to 30 minutes at a time without requiring a seated rest. She remained active in recreational activities and enjoyed tending to the indoor plants of the facility. This activity required her to carry a filled watering can while she walked to the various locations where plants were located. Outdoors, she took pleasure in tending to a small garden; this required forward bending and kneeling. Approximately 6 months ago, while tending to the garden, the patient “caught her foot” on a brick while stepping backward, and fell. According to the medical record, no injuries were sustained. After a facility‐required rehabilitation “fall screen,” the patient refused physical therapy intervention.
A routine quarterly screening examination, conducted 72 hours prior to the onset of this intervention, indicated that further evaluation by a physical therapist was warranted, as the patient reported that she was “shuffling her feet” and that her feet felt “heavy at times.” The patient had no additional neurological, cardiac, or musculoskeletal diagnoses that could account for her loss of balance since prior intervention. She had no history of orthostatic hypotension. In the last 6 months she had no surgeries.
Her past medical history included bipolar disease and schizophrenia, well controlled with Seroquel. Side effects of Seroquel include diminished or uncontrollable movement, excessive muscle tone, tremor, weakness, neck rigidity, postural hypotension, rapid or irregular heartbeat, dizziness, drowsiness, headache, abdominal pain, indigestion, and constipation. She has been taking this medication for over a year, without interruptions or dosing changes. Her physician did not believe that side effects of Seroquel contributed to her fall.
Over the past 6 months, the patient received 2 weeks of physical therapy once a day, 3 times a week, after complaining of shoulder pain following extensive outside gardening. Interventions included moist heat, ultrasound, and therapeutic exercise to the right shoulder. She had no loss of balance at that time. Since then, she has had no further complaints of impairment or dysfunction in her right upper extremity.
Prior to participation in this case report, this resident signed an informed consent form. This case report conformed to the requirements of the United States Health Insurance Portability and Accountability Act.
Although the patient wore bi‐focal glasses for reading and distance, she denied visual impairment while using them. She also denied auditory impairment and dizziness. Her postural blood pressure (mmHg) was within normal limits (126/84 supine, 126/82 sitting, and 124/82 standing), as was her heart rate (bpm) and rhythm (76/regular supine, 78/regular sitting, and 78/regular standing). Range of motion and strength assessments were unremarkable, except for pain‐free limited cervical rotation to the left and right. Muscle tone in her 4 extremities was within normal limits. Proprioception (finger‐nose and heel‐shin) and coordination (rapid alternating movement) testing, as described by Umphred24 were unimpaired. Observational gait analysis, without an assistive device, revealed a wide base of support. An average measured gait speed of 1.2 m/s during a 6‐minute walk test was within normal limits for her sex and age.25
Clinical outcome measure data, including the Berg Balance Scale (BBS)26, the Dynamic Gait Index (DGI)27, the Timed Up and Go Test (TUG)28, the Activities‐specific Balance Confidence Scale (ABC)29 were collected before and after the intervention period. The BBS, the DGI, and the TUG were specifically selected to assess balance and the patient's ability to adapt gait to changes in task demands. The ABC Scale was selected to assess the patient's confidence level while performing tasks. The Mini Mental State Examination (MMSE)30 was conducted before the intervention period only. It was selected to assess the patient's general cognitive ability, including orientation, registration, attention and calculation, recall, and language.
The BBS, which has good internal consistency, sensitivity, specificity, content and construct validity, and inter‐rater reliability 26,31–33 was selected for its ability to reliably test functional balance in an older adults and predict fall risk.34 The BBS is based on an ordinal scale with 4 levels of performance across 14 activities of increasing challenge. It allows for a maximal possible score of 56. A cut‐off score on the BBS of 49 or less (77% sensitivity, 86% specificity) yields a predictive probability of falls in the elderly.27 The patient earned a score of 48, demonstrating unsteadiness and difficulty while placing alternating feet on a stool, and during tandem and single‐leg stance.
A minimal detectable change (MDC) is defined as the minimal amount of change that is not due to variation in measurement. 35 Scores at or above the MDC value are due to patient improvement on the test rather than measurement error. The literature indicates that a MDC of 5 points on the BBS in an older adult is clinically significant and not due to chance.36
The DGI, which has excellent inter‐rater reliability and test‐retest reliability,37 as well as concurrent validity with the BBS,38 was selected for its ability to measure mobility, function, and dynamic balance.39 The DGI rates performance on a 4‐point ordinal scale from 0 (lowest level of function) to 3 (highest level of function) on 8 aspects of gait, with a maximal score of 24. Boulgarides et al40 described the DGI as the most challenging gait mobility test available. A cut‐off score on the DGI of 19 or less (59% sensitivity, 64% specificity) provides a predictive probability of falls in the elderly.27 The patient demonstrated instability during ambulation with head turns in the horizontal direction, with pivot turns, and while stepping over and around obstacles. She used a railing while ambulating up and down stairs. An MDC value for older adults who complete the DGI was not confirmed in the literature.
The TUG, has good content validity, construct validity, inter‐rater reliability, as well as sensitivity and specificity,41–43 and was selected because TUG times are correlated with functional independence (eg, the more time taken, the more dependent an elderly individual is in activities of daily living).44 A cut‐off score of 13.5 seconds on the TUG is predictive of older adults who fall.42 The patient's TUG time was 14.9 seconds. Although a study of 26 participants with idiopathic Parkinson's Disease reported an MDC of 2 seconds,45 no studies have provided an MDC value for older adults with balance dysfunction.
The ABC Scale was used to assess the patient's confidence (0%=no confidence and 100%=completely confident) in her postural control. It includes 16 different activities (with or without an assistive device such as a railing) ranging from ambulating within the facility (her “home”) to outside on icy sidewalks. The ABC Scale has been used in various studies among older persons and it has acceptable measurement properties.46 A cut‐off score of 85% or less in older adults identifies those with balance dysfunction.47 Lajoie and Gallagher48 indicate that a score of less than 67% represented older adults at risk for falling. The patient scored an 88% and indicated her lowest levels of confidence occurred while ambulating down a ramp and walking down stairs. In addition, the patient stated she would have very little confidence if she had to do either of these activities without a handrail. ABC scale MDC values of 18% to 38% for older adults have been noted in the literature.26,29,49
The MMSE evaluates general cognitive ability, including orientation, registration, attention and calculation, recall, and language. A score of less than 25 suggests mild cognitive impairment, while a score of less than 21 suggests moderate cognitive impairment.30 The MMSE has demonstrated good test‐retest reliability with the same or different assessor.30 The patient scored 29/30 on the MMSE, indicating she had a normal cognitive ability. This was an important factor to consider, as the intervention required the subject to follow multi‐step instructions and to effectively use the hand controller to participate in the game.
Although this patient reported a fairly high level of confi dence in her balance performance, as demonstrated by her ABC scale score, and did not indicate any participation limitations, clinical testing revealed balance instability which became more evident when this patient's base of support was narrowed in standing, during ambulation with horizontal head movement, walking while turning and stepping over objects, and when using stairs, all without the use of an assistive device. Her BBS, DGI, and TUG scores indicated that she was at risk for falling, corresponding primarily with a somatosensory deficit, versus visual or vestibular. Given the results of her clinical tests, her previous and more recent history of falls, coupled with her reported changes in gait; physical therapy intervention in the form of balance training was warranted.
Physical Therapy Diagnosis and Plan of Care
Based on the Guide to Physical Therapist Practice,15 this patient was classified within the 5A preferred practice pattern: primary prevention/risk reduction for loss of balance and falling. Results of the clinical measure tests led to a physical therapy diagnosis of abnormality of gait due to limitations in postural stability related to an unspecified balance disorder. The patient was an appropriate candidate to receive physical therapy intervention to address her risk of falling. She was willing to participate in a novel treatment approach.
The goals of physical therapy were to decrease her risk of falling by shifting her outcome scores favorably away from the fall risk cut‐off scores of each test, as well as to raise her scores above the known MDC levels. Her goal of improved balance would be indicated by: (1) increasing her BBS score to 50/56, (2) increasing her DGI score to 21/24, (3) decreasing her TUG time to ≤ 13.5 seconds, and (4) eliminating her self‐perceived walking impairment of “shuffling her feet.” This episode of care was projected to last 6 sessions over a 2‐week period, which was an average frequency and duration for this facility.
The Nintendo Wii, a commercially available interactive video game console system that uses a remote, hand‐held motion‐sensing wireless controller, combined with a 27‐inch digital color monitor, was employed as the sole balance training device. The total retail cost of these 2 components was less than $500. The system uses Wii Sports software, a collection of 5 sport‐simulations designed to use the motion‐sensing capabilities of the Wii controller. Bowling was selected as the sportsimulation from among available simulations because it most closely resembled gardening activities (eg, crouching). The Wii was chosen to establish if its use, within a physical therapy plan of care, might reduce this patient's fall risk. The subject did not participate in any other form of physical therapy intervention other than as described.
The patient participated in 6 Wii bowling sessions of 60 minutes each (which was the time required to complete the initial intervention), for a total of 6 hours of treatment over a 2‐week period. Standard rules of bowling and score‐keeping were used. The patient played at least 2 games per session. The 2‐player mode was used: the patient competed against the investigator. The patient's individual bowling time was approximately 40 minutes per session. Initially, the investigator provided verbal cues to facilitate the patient's cadence and weight shift, cuing was discontinued as unnecessary by the fourth session. The investigator provided guarding for safety during the first 2 sessions. Guarding was not necessary thereafter.
The first session consisted of orientation to the operation of the controller and method to release the simulated ball. Both demonstration and verbal instructions were provided. The patient had several opportunities to practice the activity. She used no assistive device during bowling sessions. Encouragement and praise were provided throughout each session.
Wii bowling has 3 components: approach, arm swing, and release (delivery) of the simulated ball. To begin, the patient sat in a chair while holding the controller in her dominant (right) hand (Figure 1a). She was instructed to stand when ready, and place the controller in front of her chest, simulating a bowling ball (Figure 1b). She stood 3 meters (10 feet) away from a simulated “foul line” marked on the floor, directly facing the monitor located 3 meters beyond the foul line. The patient watched the monitor to observe a transparent character whose actions mimicked the movement of her body, as detected by the movement of the controller.
A 3‐step approach was employed. Because she was righthand dominant, her initial step was with her left foot (Figure 1c). She then stepped forward briskly with her right foot as she extended her right elbow and shoulder, bringing the controller behind her (Figure 1d). On the third step (with her left leg) she quickly flexed her right shoulder, keeping her elbow extended, and released the virtual ball while her left upper extremity was extended to help her maintain upright stability (Figure 1e and 1f). During delivery, the patient watched the movement of the character on the monitor as it walked toward a virtual release point, based on her movement. The speed and rotation of the patient's arm determined the speed and spin of the virtual ball. She was allowed a seated rest of approximately 30 to 45 seconds during her opponent's turn. This allowed the patient sufficient recovery time between frames. No changes in the intervention occurred during this case study.
This intervention was chosen because it involved both a low cost 2‐dimensional interactive VR device, as well as activity that involved many of the key biological systems (eg, visual, somatosensory, vestibular) involved in maintaining balance. In terms of the neural system and cognition, the patient was required to understand the multiple steps of the delivery, to use hand‐eye coordination to properly use the controller, as well as maintain attention to task to effectively release the virtual bowling ball. Visually, she needed to complete the task while stabilizing her gaze at a monitor as she stepped toward it. Using her somatosensory system, she required proprioception to maintain her center of gravity as she moved her right arm through a full arc of extension and flexion during the delivery. Although her vestibular system was not challenged through isolated horizontal or vertical head movements, the act of rising from the chair and ambulating toward the monitor required her vestibular system to register linear acceleration and changes in gravitational force. Additionally, her vestibular system assisted in gaze stabilization through the vestibulo‐occular reflex. Although she was allowed rest periods, the activity challenged her musculoskeletal system through multiple repetitions of rising from a chair, ambulation from and to the chair, and completion of the delivery.
The results of all clinical outcome measures are summarized in Table 1. The patient's BBS score increased by 5 points, from 48 to 53. Two specific components of the BBS showed the most improvement. The patient was able to place alternating feet on a step stool, completing 8 steps in 12.5 seconds compared with a pretest time of 20.5 seconds on this activity. She also was able to place her feet in tandem and hold the position for more than 30 seconds, compared with an inability to hold the position for at least 15 seconds on initial examination.
The patient demonstrated a 2 point increase in her score on the DGI from 19 to 21. The patient improved her ability to ambulate without an assistive device while incorporating a pivot turn: she pivoted safely within 3 seconds, as compared to 4 seconds on initial examination. She was also able to navigate obstacles without changing gait speed, as compared to slowing down and adjusting her steps during initial examination.
At the end of the intervention period, the patient was able to complete the TUG in 10.5 seconds, as compared to 14.9 seconds at examination, a reduction of 4.4 seconds. Her ABC Scale score increased by 2% from 88% to 90%.
In interviews with the patient during, and at the end of the intervention period, she reported improvements in her balance, ambulation ability, and confidence. She commented that she was walking with more of a “spring in her step,” that her feet no longer felt heavy, and that she did not feel she was shuffling her feet while walking within the facility. In terms of motivation and enjoyment of the treatment intervention, the patient offered several subjective comments verifying her satisfaction and optimistic anticipation of future intervention sessions.
Balance dysfunction is a major contributor to falls in the adults over 65 years of age. This has serious implications in society because of its correlation to falls, injury, and loss of functional independence in the elderly population.12 Advanced age has been associated with decreased clinical performance on balance testing.50 However, physical therapists can play a vital role in the screening, prevention, and treatment of falls, especially among aging adults, through the use of traditional and innovative approaches.
Virtual reality is a promising innovative technology used by physical therapists as a component of balance training.51 Standard VR systems are expensive and not within the budgets of many physical therapy settings. Technology is advancing such that VR is now affordable, realistic, and clinically feasible intervention available to physical therapists working with older adults with balance impairment. Video games that simulate a 2‐dimensional interactive virtual environment have emerged as a low‐cost alternative to 3 dimensional VR. Although anecdotal evidence exists of Nintendo Wii‐based VR balance training in physical therapy clinical settings, empirical evidence is lacking; there are few reports of its use as an intervention for elderly individuals with balance deficits at risk for falls.
In this case report, an 89‐year‐old resident of a nursing home, who was identified to be at risk for falling, participated in 6 sessions (3 times per week for 2 weeks) of physical therapy using the Nintendo Wii bowling simulation program. At the conclusion of the course of physical therapy, the patient demonstrated a decrease in her fall risk as demonstrated by an increase in her BBS and DGI scores above the fall risk cut‐off scores and a decrease in her TUG time below the fall risk cut‐off score. She also had a clinically significant (MCD) improvement in her BBS score.
According to Shumay‐Cook et al, “In the range of 54 to 46, a 1‐point decrease in the Berg Balance Scores led to a 6% to 8% increase in fall risk.”27(p817) Based on this model, the 5 point increase in the patient's BBS correlated with a 30% to 40% reduction in her fall risk. This increase also met the MDC value for the BBS, and was therefore clinically significant, as well as above the fall risk cut‐off score.
Medley et al determined that, “Lower DGI scores were associated with increased fall risk, but the relationship was not linear. For example, in the score range of 22 to 24, a 1‐point decrease in the DGI resulted in a 3% increase in fall risk. In contrast, a 1‐point decrease in the 18–20 range resulted in a 6–8% increase in fall risk.”52(p1406) Therefore, the increase in the patient's DGI score by 2 points decreased her likelihood of falling by 12–16% and also raised her score above the fall risk cut‐off point. With regard to the TUG, this patient had a 4.4 second decrease in her time and a score below the cut‐off point for fall risk.
The patient's 2% improvement in her ABC scale score was not clinically significant as it did not meet the MDC value. A ceiling effect also existed, as the patient's initial score was near the maximum possible for the test, and well above the fall risk cut‐off score. Although her score change was not clinically significant, the patient provided a subjective comment that she no longer felt she was “shuffling her feet.” She also provided comments that described her motivation and enjoyment of the treatment intervention. Although this information does not represent a measurable improvement, it potentially supports the use of a nontraditional physical therapy intervention that can be used to increase patient adherence while undergoing treatment for balance disorders.
There are several limitations to this case report to consider. First, a single physical therapist examined, provided intervention, and re‐examined this patient. This may have created positive bias in reporting outcomes. Second, because a case report documents the effects of therapy on a single patient, results cannot be reliably generalized to other patients receiving physical therapy intervention.
A patient‐centered limitation exists in that, although the patient had a history of falls, she was diagnosed with an unspecified balance disorder. This lack of specificity makes it difficult to determine which components of balance dysfunction (somatosensory, visual, and/or vestibular) were impacted by this intervention. Finally, this case report did not assess whether the intervention improved the patient's overall functional ability (ADLs/IADLs).
In conclusion, the BBS, DGI, and TUG clinical outcome measures used in this case study are easily administered in a variety of settings, readily available, and are both reliable and valid. They are not excessively time consuming to administer, and can be used to reassess change over time with intervention.
The Nintendo Wii is a relatively inexpensive interactive video game system that simulates several activities, including bowling, as was used in this case report. Because of its ease of use, enjoyment, and relatively low cost, it has the potential to be a widely used intervention for physical therapists who work with older persons with balance dysfunction. Its use with this subject appears to have reduced fall risk, based on postintervention improvement of scores on the measures used to assess balance.
The results of this case report favor the possibility that such an intervention could produce improvement in balance dysfunction and reduction in fall risk for other similar patients. To date, few studies have been conducted to determine if this intervention produces a measurable improvement in balance dysfunction and/or reduction in fall risk. The data from this case report supports the importance to develop randomized and controlled studies designed to examine the effectiveness of this intervention with more rigor.
1. Web-based Injury Statistics Query and Reporting System (WISQARS). 1/15/08; Available at: www.cdc.gov/ncipc/wisqars
. Accessed September 26, 2008.
2. Stevens JA, Corso PS, Finkelstein EA, Miller TR. The costs of fatal and non-fatal falls among older adults. Inj Prev.
3. Englander F, Hodson TJ, Terregrossa RA. Economic dimensions of slip and fall injuries. J Forensic Sci.
4. Hausdorff JM, Rios DA, Edelberg HK. Gait variability and fall risk in community-living older adults: a 1-year prospective study. Arch Phys Med Rehabil.
5. Hornbrook MC, Stevens VJ, Wingfield DJ, Hollis JF, Greenlick MR, Ory MG. Preventing falls among community-dwelling older persons: results from a randomized trial. Gerontologist.
6. Rubenstein LZ. Falls in older people: epidemiology, risk factors and strategies for prevention. Age Ageing.
7. 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.
8. Ellis AA, Trent RB. Do the risks and consequences of hospitalized fall injuries among older adults in California vary by type of fall? J Gerontol A Biol Sci Med Sci.
9. Moreland J, Richardson J, Chan DH, et al. Evidence-based guidelines for the secondary prevention of falls in older adults. Gerontology.
10. Bueno-Cavanillas A, Padilla-Ruiz F, Jimenez-Moleon JJ, Peinado-Alonso CA, Galvez-Vargas R. Risk factors in falls among the elderly according to extrinsic and intrinsic precipitating causes. Eur J Epidemiol.
11. Bottomley JM, Lewis CB. Geriatric Rehabilitation: A Clinical Approach
. 2nd ed. Upper Saddle River, NJ: Prentice Hall; 2003.
12. Matsumura BA, Ambrose AF. Balance in the elderly. Clin Geriatr Med.
13. Westlake KP, Culham EG. Sensory-specific balance training in older adults: effect on proprioceptive reintegration and cognitive demands. Phys Ther.
14. Teasdale N, Simoneau M. Attentional demands for postural control: the effects of aging and sensory reintegration. Gait Posture.
15. American Physical Therapy Association. Guide to physical therapist practice. 2nd ed. Phys Ther.
16. Frankel JE, Bean JF, Frontera WR. Exercise in the elderly: research and clinical practice. Clin Geriatr Med.
17. Gillespie LD, Gillespie WJ, Robertson MC, Lamb SE, Cumming RG, Rowe BH. Interventions for preventing falls in elderly people. Cochrane Database Syst Rev.
18. Howe TE, Rochester L, Jackson A, Banks PM, Blair VA. Exercise for improving balance in older people. Cochrane Database Syst Rev.
19. Cunningham D, Krishack M. Virtual reality: a wholistic approach to rehabilitation. Stud Health Technol Inform.
20. Betker AL, Szturm T, Moussavi ZK, Nett C. Video gamebased exercises for balance rehabilitation: a single-subject design. Arch Phys Med Rehabil.
21. Flynn S, Palma P, Bender A. Feasibility of using the Sony PlayStation 2 gaming platform for an individual poststroke: a case report. J Neurol Phys Ther.
22. Merians AS, Jack D, Boian R, et al. Virtual reality-augmented rehabilitation for patients following stroke. Phys Ther.
23. Tamura T, Sekine M, Shinchi T, Yuji T, Higashi Y, Fujimoto T. PC-based rehabilitation tool for the elderly. Conf Proc IEEE Eng Med Biol Soc.
24. Umphred D. Neurological Rehabilitation
. 4th ed. St. Louis, MO: Mosby, Inc; 2001.
25. Bohannon RW. Comfortable and maximum walking speed of adults aged 20-79 years: reference values and determinants. Age Ageing.
26. Holbein-Jenny MA, Billek-Sawhney B, Beckman E, Smith T. Balance in personal care home residents: a comparison of the Berg Balance Scale, the Multi-Directional Reach Test, and the Activities-Specific Balance Confidence Scale. J Geriatr Phys Ther.
27. Shumway-Cook A, Baldwin M, Polissar NL, Gruber W. Predicting the probability for falls in community-dwelling older adults. Phys Ther.
28. Podsiadlo D, Richardson S. The timed “Up & Go”: a test of basic functional mobility for frail elderly persons. J Am Geriatr Soc.
29. Powell LE, Myers AM. The Activities-specific Balance Confidence (ABC) Scale. J Gerontol A Biol Sci Med Sci.
30. Folstein MF, Folstein SE, McHugh PR. “Mini-mental state”. A practical method for grading the cognitive state of patients for the clinician. J Psychiatr Res.
31. Newstead AH, Hinman MR, Tomberlin JA. Reliability of the Berg Balance Scale and balance master limits of stability tests for individuals with brain injury. J Neurol Phys Ther.
32. Sackley C, Richardson P, McDonnell K, Ratib S, Dewey M, Hill HJ. The reliability of balance, mobility and selfcare measures in a population of adults with a learning disability known to a physiotherapy service. Clin Rehabil.
33. Wang CY, Hsieh CL, Olson SL, Wang CH, Sheu CF, Liang CC. Psychometric properties of the Berg Balance Scale in a community-dwelling elderly resident population in Taiwan. J Formos Med Assoc.
34. Roma AA, Chiarello LA, Barker SP, Brennaman SK. Examination and comparison of the relationships between strength, balance, fall history, and ambulatory function in older adults. J Geriatr Phys Ther.
35. Haley SM, Fragala-Pinkham MA. Interpreting change scores of tests and measures used in physical therapy. Phys Ther.
36. Steffen T, Seney M. Test-retest reliability and minimal detectable change on balance and ambulation tests, the 36- item short-form health survey, and the unified Parkinson disease rating scale in people with parkinsonism. Phys Ther.
37. Shumway-Cook A, Gruber W, Baldwin M, Liao S. The effect of multidimensional exercises on balance, mobility, and fall risk in community-dwelling older adults. Phys Ther.
38. Whitney S, Wrisley D, Furman J. Concurrent validity of the Berg Balance Scale and the Dynamic Gait Index in people with vestibular dysfunction. Physiother Res Int.
39. Cattaneo D, Jonsdottir J, Zocchi M, Regola A. Effects of balance exercises on people with multiple sclerosis: a pilot study. Clin Rehabil.
40. Boulgarides LK, McGinty SM, Willett JA, Barnes CW. Use of clinical and impairment-based tests to predict falls by community-dwelling older adults. Phys Ther.
41. Isles RC, Choy NL, Steer M, Nitz JC. Normal values of balance tests in women aged 20-80. J Am Geriatr Soc.
42. Shumway-Cook A, Brauer S, Woollacott M. Predicting the probability for falls in community-dwelling older adults using the Timed Up & Go Test. Phys Ther.
43. Steffen TM, Hacker TA, Mollinger L. Age- and genderrelated test performance in community-dwelling elderly people: Six-Minute Walk Test, Berg Balance Scale, Timed Up & Go Test, and gait speeds. Phys Ther.
44. Lusardi MM, Pellechia G, Schulman M. Functional performance in community living older adults. J Geriatr Phys Ther.
45. Lim LI, van Wegen EE, de Goede CJ, et al. Measuring gait and gait-related activities in Parkinson's patients own home environment: a reliability, responsiveness and feasibility study. Parkinsonism Relat Disord.
46. Botner EM, Miller WC, Eng JJ. Measurement properties of the Activities-specific Balance Confidence Scale among individuals with stroke. Disabil Rehabil.
47. Whitney SL, Wrisley DM, Marchetti GF, Gee MA, Redfern MS, Furman JM. Clinical measurement of sit-tostand performance in people with balance disorders: validity of data for the Five-Times-Sit-to-Stand Test. Phys Ther.
48. Lajoie Y, Gallagher SP. Predicting falls within the elderly community: comparison of postural sway, reaction time, the Berg balance scale and the Activities-specific Balance Confidence (ABC) scale for comparing fallers and nonfallers. Arch Gerontol Geriatr.
49. Miller WC, Deathe AB, Speechley M. Psychometric properties of the Activities-specific Balance Confidence Scale among individuals with a lower-limb amputation. Arch Phys Med Rehabil.
50. Kammerlind AS, Ledin TE, Odkvist LM, Skargren EI. Effects of home training and additional physical therapy on recovery after acute unilateral vestibular loss—a randomized study. Clin Rehabil.
51. Sveistrup H. Motor rehabilitation using virtual reality. J Neuroeng Rehabil.
52. Medley A, Thompson M, French J. Predicting the probability of falls in community dwelling persons with brain injury: a pilot study. Brain Inj.
Key Words:: falls,; balance dysfunction,; balance physical therapy treatments,; Wii,; geriatric physical therapy