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Assessment of Balance Disorders and Falls Risk in Persons with Parkinson’s Disease (Intervention and Prevention). Andrea L. Behrman, PhD, PT Department of Physical Therapy, College of Public Health and Health Professions McKnight Brain Institute at UF VA Brain Rehabilitation Research Center
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Assessment of Balance Disorders and Falls Risk in Persons with Parkinson’s Disease(Intervention and Prevention) Andrea L. Behrman, PhD, PT Department of Physical Therapy, College of Public Health and Health Professions McKnight Brain Institute at UF VA Brain Rehabilitation Research Center University of Florida
Acknowledgements Foundation for Physical Therapy VA Brain Rehabilitation and Research Center Kathye Light, PhD, PT Dawn Bowers, PhD William Friedman, MD William Triggs, MD James Cauraugh, PhD Philip Teitelbaum, PhD Sheryl Flynn, PT, MHS Mary Thigpen, PT, MHS, NCS Jung Chang, PT, MHS
Balance Difficulties Intrinsic Extrinsic Inherent to PD Environment Non-PD Related ADL, Task- dependent 1° Balance Disorder Associated with Movement/Cognitive Disorders- Medications
Inherent to PD • Stage III Hoehn & Yahr, balance disorder • Mid-Late in disease progression 1° Balance Disorder • 38% fall (Koller et al., 1989): person’s body involuntarily contacts the ground • 13% fall more than 1x/week • 18% suffer fractures
Nature of inherent postural disorder in PD (Horak et al. 1992; Pastor et al., 1993; Schieppati and Nardone, 1991) • Appropriate use of sensory information for postural orientation – Sensory Organization Test - (reduced sway relative to cohort performance/M-L) • Appropriate coordination of postural movement patterns in response to displacements(hip vs. ankle strategy) Program is intact. • Inflexibility of postural response patterns adapting to changes in support conditions. Planning is impaired. • Excessive antagonist activity.
Precue/focus attention when change in environment expected (i.e. see crowd ahead, change from tile to carpet) • Plan route if obstacles ahead, including stops if • a long distance or expect you will need to change direction • Prepare mentally to recover balance by stepping; teach stepping response • Prepare for probable events that will disturb balance (bus stops, elevator stops, train starts) • Adapt environment to diminish changes (i.e. stripes on floor at areas that pose difficulty)
Inherent to PD • Decreased walking speed, if < 0.6 m/secdecreased ground clearance trips FALLS Associated with Movement Disorders • Shuffling gait, decreased step length and ground clearance (< 0.8 cm) • Sudden cessations of walking: freezing • Turning difficulty (Thigpen et al., 2000) • strategies; freezing during turn, progressively smaller steps and decreased ground clearance, • > 20 steps in 360 degree turn (Lipsitz et al., 1991) • Difficulty terminating locomotion
Context-dependent/environment (ex. visual array: tile pattern change, door width / hallway / outdoors, barriers to movement, corners or furniture requiring change in direction)
Inherent to PD Associated with Cognitive Disorders • Difficulty performing 2 tasks at once (turn and talk; Bond et al., 2000) • Impairment in problem-solving and planning. May increase incidence of behavior that is high-risk for persons with PD.
Non-PD Related • Age-related changes • Sensory impairments: • visual, vestibular, proprioceptive • Weakness; inability to stand up from a chair without using one’s arms to push off (LE strength) • Gender: Females have greater frequency of • falls than males. • Muscle tightness / inflexibility • Pre-existing level of dependency: higher rate for falls – institutions vs. community
Extrinsic Medications • Depress NS (sedatives, antidepressants) • Lead to postural hypotension: a postural systolic BP decline > 20 mm Hg at one or three minutes of standing or an absolute systolic BP below 90 mm Hg • (antihypertensives, antidepressants, diuretics)
Extrinsic ADL, Task- dependent • OVERALL.Minimize balance requirements while performing ADLs and minimize cognitive tasks /conversation. Diminish balance requirement, focus on task. Break down task into steps.
DRESSING.Organize closet/drawers for safety/access to clothes (diminish amount of reaching while standing). Sit down on stable chair when dressing, focus on buttons, etc. Clock turn out of closet. • BATHING.Sit or support with rail while bathing / showering (remove balance as a factor, than can concentrate on bathing/drying, etc.) Use wash mitt. • TOILETTING,compounded by urgency. • Walking in/out bathroom. Grab rails, raised toilet seats. Mark floor for consistency of steps • through doorway and in BR. Clock turn in BR. • Night light. • Bedside commode/urinal. • Bedside cues for getting out of bed.
Extrinsic Environment • Support surface on which person is standing: uneven, cracks, slippery, carpeted • Environment free of obstacles & clutter • Adequate lighting, night light in bedroom/halls • Appropriate shoes: low broad heel, lace up • Stairs: differentiation of edges and stairs • Home Safety Check List
Balance and Falls Risk – Falls Assessment Performance in the clinic/lab on motor tasks vs. Assessment under real-life circumstances • Does performance in the clinic correlate with performance at home or in the community? • Does performance in the clinic predict performance in the home? • Are assessment tests reliable, sensitive, predictive?
Clinical Assessments of Balance • Standing balance (Smithson, Morris, & Iansek, 1998) • Steady standing: feet apart, feet together, tandem stance, single limb stance • Self-initiated movements: arm raise, functional reach(1 reach), bend-reach, step test • External perturbation to upright stance: shoulder tug • Differentiated persons with PD who have a hx of falls from 1) persons with PD and no hx of falls and from 2) control subjects (no hx of falls) • Reliable measures 1 week later • Stage II and III, peak-dose of meds
Standing balance Functional reach (Behrman et al., 2002) • 1 practice with average of 3 test trials as test score • 1 practice with 1st test trial as test score • Both scores differentiated persons with PD who have a hx of falls from • persons with PD and no hx of falls and from • control subjects (no hx of falls)
Criterion for falls risk: reach < 25.4 cm (Duncan et al., 1992) FR test validity: sensitivity, specificity, predictive value
Sensitivity = a / (a + c) = 30% Specificity = d / (b + d) = 92% + Predictive value = a / (a + b) = 90% - Predictive value = d / (c + d) = 36% a = true positives, persons with a history of falls correctly identified as at risk; b = false positives, persons incorrectly identified as at risk for falls; c = false negatives, persons who are incorrectly identified as not at risk for falls; d = true negatives, persons with no history of falls correctly identified as not at risk. (adapted from Behrman et al., 2002)
Standing, transitional movements, and functional tasks: Berg Balance test • Bogle Thorbahn & Newton, 1996 • Residents of 2 independent life-care communities (n=66), M = 79.2 yrs • Mixed diagnoses: 38% orthopedic or neurologic impairment (n=5, PD) • 53% test sensitivity for predicting positive falls history with 45 / 56 as cutoff or criterion score for risk of falls • 96% test specificity • (Behrman et. al, unpublished data) • Community-dwelling population, n= 66 with PD (reported incidence of falls, n=18 controls (- falls history) • Test scores discriminated overall group with PD (= 48. 8) from controls (M = 55.7) • Test scores discriminated group with PD/+falls hx (M = 47.2) from • 1) group with PD/-falls hx (M = 52.4) and 2) controls (55.7) • Comparing balance scores for individual items across the three groups • determined a significant group effect for only 3 / 14 test items
Berg Balance Test Items • Sitting to standing • Standing unsupported • Sitting unsupported • Standing to sitting • Transfers • Standing with eyes closed • Standing with feet together • Reaching forward with an outstretched arm • Retrieving object from floor • Turning to look behind • Turning 360° • Placing alternate foot on stool • Standing with one foot in front of the other foot • (tandem stance) • 14. Standing on one foot * * *
Postural response test(Pastor et al., 1996) • If clinician pull backwards on patient atshoulders, typical response is lack of a posterior stepping response and a rigid fall backwards into clinician’s arms. • Patient in stance with feet 10 cm apart. • “I am going to tap you off balance, and I won’t let you fall.” Use to quantify baseline performance and outcome of stepping training. • 0 Stays upright without taking a step • Takes one step backwards but remains steady • Takes more than one step backwards, followed by the need to be caught • Takes several steps backwards, followed by the need to be caught • Falls backwards without attempting to step
Timed Up and Go (Podsiadlo and Richardson, 1991; Morris & Morris, 2001) Reliable: Practice Trial, Test trials 1-3 Differentiates on/off medication performance and Subjects with PD and adults without PD Turning difficulty(Thigpen et al., 2000) Fall while turning associated with increased hip fracture in the elderly. Evaluated turning strategy, time in turn, number of steps Differentiated persons with turning difficulty > 20 steps in 360° turn(Lipsitz et al., 1991)
Falls Records (Yekutiel, 1993 – 2 case studies) • Context-dependent vs. lab/clinic-based assessments • Individual’s specific environment • Falls diary • Draw plan of home to scale and copy • Mark each fall on the plan • Use 1 copy / day • Use during baseline period prior to initiating therapy, during therapy, and post-completion of therapy • Information accumulated: • Where do falls occur? • Under what circumstances/tasks? • Time of day, association with meds • Identify each individual’s particular problem • Plan intervention accordingly. • Continual assessment over time, % reduction of falls. • Factors accounting for falls may change.
Balance Difficulties Intrinsic Extrinsic Inherent to PD Environment Non-PD Related Fear of Falling ADL, Task- dependent Associated with Movement/Cognitive Disorders- Context-dependent Medications
Fear of Falling Falls Efficacy Scale (Tinetti) Measures a person’s confidence in doing ADL without falling. On a scale of 1 to 10 with 10 meaning NOT confident or sure at all, 5 being FAIRLY confident/sure, and 1 being COMPLETELY confident/sure, how confident/sure are you that you can do each of the following without falling? • Clean house (e.g. sweep or dust) 2. Get dressed/undressed • Prepare simple meals (no carrying) 4. Take a bath/shower • Simple shopping 6. Get in/out of car • Go up and down stairs 8. Walk around neighborhood • 9. Reach into cabinets or closets 10. Hurry to answer the phone Self-efficacy has a strong correlation with 1) frailty: person self-limits activities and 2) incidence of falls.
Progression of PD / Balance Impairments • Early - • Movement disorders that may affect balance • gait pattern: short steps • gait akinesia/hypokinesia • freezing • Delayed stepping response to external perturbation in steady stance • No incidence of falls, yet difficulty with balance Intervention: Attentional strategies Visualization/verbal cues Visual cues Stepping response Maintain musculoskeletal and cardiovascular systems in good condition.
Mid: Impact of visual environment increased Gait performance, shuffling Falls occur Assessments: TUG, Fxal Reach, tandem stance, turning, postural response test, STS, postural hypotension, Falls Efficacy scale, Home Safety Checklist Intervention:Falls prevention emphasis. Restructure environment. Review falls hx, task analysis, impact of environment, pt/family education re: falls risk, falls diary: date, time, location, reason for fall. Maintain musculoskeletal and cardiovascular systems in good condition. Work within everyday tasks, home, and community. F/up every 3 months or as necessary.
Prieto N & Light KE. (1999). Balance, Frailty, and Falls Assessment, and Intervention: Case study of a client with Parkinson’s disease.
Balance Difficulties Intrinsic Extrinsic Inherent to PD Environment Non-PD Related Fear of Falling ADL, Task- dependent Associated with Movement/Cognitive Disorders- Context-dependent Medications
“A phenomenon like this makes me wonder: May psychological attitudes somehow influence the severity of Parkinsonian disabilities? Or, alternatively, may some nerve circuit situated deep in the more primitive part of our nervous system be capable when called upon under certain circumstances, of bypassing malfunctional striatal linkages, thereby making possible an instinctive, semi-automatic life-saving ability to walk? All of this forces another difficult question. If the skills for walking can be reactivated to serve a thoroughly disabled Parkinsonian patient, even if transiently, and under specific circumstances, can some way be discovered---whether by a trick of the will or by repetitive conditioning---of bringing still other neuronal pathways and connections back into dependable service?” (McGoon, 1990)
“One must cease to regard all patients as replicas, and honour each one with individual attention, attention to how he is doing, to his individual reactions and propensities; and, in this way, with the patient as one’s equal, one’s co-explorer…one may find ways, tactics, which can be modified as occasion requires.” (Sacks, 1982)
Correlates for Home-based Standardized Assessments – Problem Specific Timed Functional Movement Battery (Light et al., self-selected, fast pace) adapt to functional activities in home Time to dress Distance walking / day
End of the day: Controversy or new BWS-locomotor training
Locomotor training with BWS, treadmill, and manual assistance
Equilibrium during propulsive movement Basic movement synergy Adaptation to behavioral goals and external constraints Functional Walking: Control Requirements by the Nervous System Adapted from Forssberg, 1982; Barbeau et al., 1999
“Rehabilitation’s job is to take your body as itis and to maximize your capabilities within recognized limitations. This is a difficult acknowledgement. Rehabilitation seems only second best. To fully accept rehabilitation, for most of us, it is to effectively abandon recovery. Rehabilitation can give you strength, reeducation, skills and real improvement, but no cure.” Corbet, 1980 Editor, New Mobility, Spinal Network