Freezing of Gait Phenomenon: What s the hold up? May 31, 2017 Amanda Wu, PT, DPT, NCS, CBIS

Transcription

1 Freezing of Gait Phenomenon: What s the hold up? May 31, 2017 Amanda Wu, PT, DPT, NCS, CBIS

2 Objectives Understand freezing of gait (FOG), its functional impact, and the characteristics of those likely to experience FOG Identify when FOG is likely to occur Understand the possible causes of FOG Identify key components of evaluation and outcome measures for FOG Identify specific physical therapy interventions to address FOG

3 Freezing of Gait

4 Gait in Parkinson s Disease (Spildooren et al) Parkinsonian gait Commonly see a decreased step length and reduced velocity Freezing of gait (FOG) Inability to produce effective forward steps despite the intention to walk Lasting seconds (< 1 minute) in which walking is halted Often preceded by hastening or festination of gait Small steps at a high frequency Poorly treated by dopaminergic medications or very large doses are required to improve FOG Not just specific to gait, but can be related to speech and movements of (Nonnekes et al) fingers

5 Freezing of gait ~50% of all patients with Parkinson s disease (Spildooren et al) (PD) will experience FOG 10% of FOG is seen in early stages of PD (mild symptoms) 80% of FOG is seen in later stages of PD (severe symptoms) (Plotnik et al) Coincides with greater cognitive decline

6 Increased risk for falls Depression Reduced quality of life Impact of FOG

7 Atypical Parkinson s Side note: FOG is not specific to PD Progressive Supranuclear Palsy Pure Akinesia Syndrome Multiple System Atrophy Corticobasal Degeneration (Brownder et al) If FOG is one of the first signs the diagnosis may be Atypical Parkinson s

8 Characteristics of Freezers Rigidity as early symptom is positive predictor for FOG (Macht et al) Tremor as early symptom negatively associated with development of FOG Early occurrence associated with global cognitive (Browner et al, Heremans et al) decline and depression Deficits of executive functioning Visual impairments

9 When/Where does it occur? Turning Most common task that induces FOG Around an obstacle, returning to sit Usually impaired in earlier stages of PD Narrow doorways Change of environment Thresholds, changes in flooring Initiation of gait Walking under time pressure Rushing to answer phone Dual tasking Stress and/or anxiety (Plotnik et al, Browner et al, Beck et al)

10 What causes FOG? Initially thought to be a purely motor system deficit Shifted to a multisystem deficit to include: Neurochemical/Neurostructural Cognitive Sensory Motor Emotional Overload of processing resources may block motor output (Heremans et al, Browner et al, Sarbaz et al)

11 Causes of FOG Neurochemical/Neurostructural Decreased dopamine Increased resistance to dopaminergic drugs Scaling of lower limb amplitude impaired: controlled by higher levels of the CNS and then maintained by the basal ganglia Under normal conditions basal ganglia match preselected stride length to achieve goal ; basal ganglia is unable to do this mismatch in amplitude across all joints Reduction in basal ganglia loops causing infiltration of non-motor information that disrupts the basal ganglia motor loop

12 Causes of FOG Sensory Beck et al found step length and gait velocity were significantly reduced in freezers compared to non-freezers when vision of lower limbs was removed Use of sensory cues at times increase episodes of FOG possibly due to sensory overload Stepping over imaginary line or line from laser pointer

13 Motor Causes of FOG Sequence Effect - gradual step to step reduction that eventually leads to freezing Threshold model - induced by accumulation of motor impairments (Schlick et al) Reduced step, coordination and symmetry Deficits in Bilateral coordination: initiation of locomotion and during turns because these require efficient coordination of leg movements Not related to abnormal tone of muscles or weakness (Sarbaz et al)

14 Causes of FOG Cognitive Associations between FOG and executive functioning decline Frontal lobe is impacted with difficulty with initiation or switching motor plans Arousal and attention factors Suggested due to increased attention required for gait Tasks that divert attention away from walking increase FOG episodes indicating cognition is a factor Beck et al found increased number of FOG episodes and percentage of time spent frozen when performing dual task compared to baseline Freezers found to gaze at pathway vs. doorway with addition of dual task possibly decreasing attentional resource

15 Causes of FOG (Martens et al) Emotional/Limbic system Anxiety = most common non-motor symptom of PD 69% of individuals with PD Greater in freezers than non-freezers Freezing precede anxiety or does anxiety lead to FOG? Increased heart rate seen prior to and during FOG episode Martens et al found freezers spent a greater percentage of trial frozen when walking in an anxiety provoking situation and had a greater number of freezing episodes in anxiety provoking setting Reduced velocity and step length Thought to contribute to overload

16 Evaluation (Nonnekes et al) HPI Feet glued or pasted to the floor FOG episodes Frequency, where, intensity, and duration of freezing episodes Medication Timing, episodes ON or OFF Presence of falls During turns OR spontaneous falls Cognitive difficulties Visual changes

17 Evaluation: Tests and Measures (Ekker et al) Visual assessment is vital Dependent upon vision to compensate for defects in automatic motor behavior Visual deficits are very common in PD and usually worse in Freezers increasing risk for falls Common deficits include: Dry eyes (reduced blinking) Blurry vision, pain Ocular motor Convergence insufficiency Impaired color discrimination and contrast sensitivity Difficulty with low light environments Impaired visuospatial ability Interferes with movement planning Visual hallucinations

18 Evaluation Cognition Executive functioning skills Indications for treatment and potential for success with use of cueing strategies Eliciting FOG Using a series of turns, narrow pathways, starts, and dual task situations Make full or rapid turns in both directions, walk with short steps as rapidly as possible

19 Outcome Measures (Bloem et al) Freezing of gait questionnaire Subjective severity of freezing of gait and how it impacts daily life 6 item scale ranging from 0-24 (higher score = greater severity) Question 3 found to be a good single question for FOG frequency Rate gait difficulties ( 2 items) and frequency/duration of most typical FOG episodes on 5 point scale ( 0 = absent to 4 = most severe) High internal consistency and good inter-intrarater reliability Criterion validity is supported by ability to distinguish freezers from non-freezers High correlations with other gait and balance measures MDC, MCID not established

20 Outcome Measure Question 14 of UPDRS Freezing when walking and rate 0-4 scale (0 = none; 4 = frequent falls) (Keus et al) Modified Parkinson s Activity Scale (MPAS) 14 items assessing general mobility with 6 items assessing FOG Observe quality of movements rating from 0 (dependent) to 4 (normal) Range from 0-56 (higher = more impaired) Includes dual tasking items MDC = 7.2 No reliability or validity data to date

21 Outcome Measures Short freezing of gait assessment (Zeigler et al) 4 situational maneuvers rated on 4 level interval scale Start to walk, turning CW, CCW, and passing through doorway Range from 0-36 Items scored from 0-3 (severity of FOG) 3 conditions: Walking, addition of motor task, and addition of cognitive task

22 Interventions

23 Intervention: Visual Cues (Beck et al) Assessed dual tasking with addition of visual cues Auditory list of random numbers in which individual was asked to count number of times a specific number was stated Results Visual cues improved step length and step time in freezers regardless of dual task Reduced number of FOG episodes Visual cues unable to ameliorate FOG during dual task Visual cues assisted to focus attention on walking or provided information to form a feed forward plan reducing reliance on proprioceptive feedback

24 Intervention: Auditory Cues Plotnik et al assessed if auditory cueing provided in environment likely to induce FOG affected the number and duration of FOG episodes Narrow passageway, doorways, turns, slalom with progressive task conditions including dual tasking and busier environments Set to 80% of the cadence and then adjusted as learning occurred Results: Lower frequency of FOG episodes and shorter duration of FOG episode during all gait trials FOG episodes remained significantly reduced in the 4 week follow up testing compared to pre-testing Increased gait speed but only statistically significant for dual tasking conditions; decreased TUG and improved ABC

25 Intervention: Gait Initiation Lu et al: Determine effects of external cue timing on the timing, magnitude, and incidence of anticipatory postural adjustments during gait initiation Setup: Provided auditory, visual, or somatosensory cueing during 3 timing protocols including countdown, fixed delay, and random delay Results: Auditory and visual cues significantly decreased the incidence of incomplete postural adjustments compared with self initiation across all cue timings Increased amplitude of initial loading and unloading forces Tactile had no significant effect on APA timing Predictable cue timings were most effective at improving the timing of APA and propulsive phase of gait initiation

26 Intervention: Turns Spildooren et al examined if turns could be improved with use of auditory cue or attentional cue Setup: Baseline trial at beginning and end, auditory cue during entire trial, attentional cue with focus on initiating turn with their head Assessed head, trunk, and pelvic rotation, head/pelvis separation, FOC occurrence, Medial COM deviation during turning, turn velocity, and knee flexion amplitude Results: FOG occurred in 52.8% of baseline and 34.6% of trials using attention strategy and 3.8% of trials with unilateral cue Cueing increased the en-bloc movement and decreased the knee flexion suggesting compensatory mechanism for reduced postural control Cueing did not affect COM suggesting mediolateral weight shift may not be of critical importance in the etiology of FOG and that en block might actually reduce FOG

27 Interventions: Turns Yang et al examined whether use of a clock turn strategy is effective on the pattern of turning steps, turning performance, and FOG during narrow turning Imagine a virtual clock: If turning R = 12, 3, 6 and if turning L = 12, 9, 6 using 3 step to cycles Results: Clock turn group had greater foot clearance than usual - turn group and clock turn group had lower step time variability Both groups had higher step time variability with addition of dual task however clock turn strategy group was no longer able to maintain foot clearance however FOG number and duration did not increase Clock turn group took less time to turn than usual - turn group Clock turn group had lower FOG severity

28 Intervention: Combination Cues Frazzitta et al assessed effect of treadmill training with auditory and visual cues vs. auditory and visual cueing only Group 1 (Treadmill) Visual cue displayed on screen with patient matching to stride Auditory cue of musical beats synchronized with the visual cues Group 2 (No Treadmill) Visual cue consisted of lines spaced according to individual stride length (increased every 3 days by 0.05m) Auditory cue same as group 1 Results: 6MWT, gait speed, stride cycle improved in both groups however treadmill significantly better than cueing only Treadmill may impose another external cue

29 Intervention: Combination Cues Schlick et al examined the effects of treadmill training with visual cues vs. treadmill training alone Treadmill training: 20 minutes up to 45 minutes with progressive speed Treadmill training with visual cues projected onto the treadmill belt Increased 10% of their step length initially Results: Gait speed and stride length improved in both, TUG only reduced in treadmill with visual cues group 2 month follow up: Both groups had reduced gait speed and stride length but treadmill only group was significantly lower; no change in TUG

30 LSVT BIG for FOG Use of large amplitude movements with cue of BIG Provide functional practice under circumstances that increase freezing episodes During freezing episode: Use of 4 S s Stop BIG Stand BIG Shift BIG Step BIG

31 Emerging Technology (Ekker et al) Walking sticks and rolling walkers that project laser line on the floor Effective in overcoming FOG and reducing falls in some patients Auditory device incorporated into glasses Effective in improving gait parameters in lab settings cost? Smart glasses Provide contrast enhancing functions Magnification of view

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34 Research Limitations Excludes those in later stages of PD (Hoehn and Yahr 4) Exclusions of those with visual impairment Exclusions of those with greater cognitive deficits Many without a long term follow up Retention of training effects is limited even in short periods of time

35 Cognitive Barriers to Cueing Interventions (Heremans et al) Successful use of cues requires an ability to retrieve them May have difficulty with using strategies Provided cues requires individuals to shift their motor control from automatic to attention demanding control Providing cue may use greater attentional resources Can create cue dependency and reduced flexibility Decreased transfer of learning

36 Special Considerations Cognition and progression of the disease Consider referrals for OT Household adaptations, lighting, safety rails, planning (Nonnekes et al) schedules to minimize stress Consider referral to Ophthalmologist (Rahman et al) Patient preference Prefer cognitive strategies over other forms of cueing Carryover is limited Require significant social support Consideration for maintenance programs

37 Take Home Points FOG is one of the most debilitating symptoms of PD, is resistant to medical management, is challenging to assess, and is a main source of falls and reduced quality of life in those with PD Therapeutic strategies using external cues can improve FOG however the effects are patient dependent and impacted by an individual's cognitive and visual impairments Effects can be short term therefore a multidisciplinary approach including caregiver support is necessary to assist with carryover of treatment strategies into the home setting

38 Questions?

39 References Rahman S, Griffin HJ, Quinn NP, Jahanshahi M. The factors that induce and overcome freezing of gait in Parkinson s disease. Behav Neurol. 2008;19: Spildooren, J., Vercruysse, S., Heremans, E., Galna, B., Verheyden, G., Vervoort, G., & Nieuwboer, A. (2017). Influence of Cueing and an Attentional Strategy on Freezing of Gait in Parkinson Disease During Turning. Journal of Neurologic Physical Therapy, 41(2), Macht, M., Kaussner, Y., Möller, J. C., Stiasny-Kolster, K., Eggert, K. M., Krüger, H., & Ellgring, H. (2007). Predictors of freezing in Parkinsons disease: A survey of 6,620 patients. Movement Disorders,22(7), Plotnik, M., Shema, S., Dorfman, M., Gazit, E., Brozgol, M., Giladi, N., & Hausdorff, J. M. (2014). A motor learning-based intervention to ameliorate freezing of gait in subjects with Parkinson s disease. Journal of Neurology,261(7), doi: /s Sarbaz, Y., Gharibzadeh, S., & Towhidkhah, F. (2012). Pathophysiology of freezing of gait and some possible treatments for it. Medical Hypotheses,78(2), doi: /j.mehy Browner, N., & Giladi, N. (2010). What Can We Learn From Freezing of Gait in Parkinson s Disease? Current Neurology and Neuroscience Reports,10(5), doi: /s

40 References Nonnekes, J., Snijders, A. H., Nutt, J. G., Deuschl, G., Giladi, N., & Bloem, B. R. (2015). Freezing of gait: a practical approach to management. The Lancet Neurology,14(7), doi: /s (15) Heremans, E., Nieuwboer, A., Spildooren, J., Vandenbossche, J., Deroost, N., Soetens, E.,... Vercruysse, S. (2013). Cognitive aspects of freezing of gait in Parkinson's Disease: a challenge for rehabilitation. J Neural Transm,120, doi: /s =0964-y Martens, K. A., Ellard, C. G., & Almeida, Q. J. (2014). Does Anxiety Cause Freezing of Gait in Parkinsons Disease? PLoS ONE,9(9). doi: /journal.pone Beck, E. N., Martens, K. A., & Almeida, Q. J. (2015). Freezing of Gait in Parkinson s Disease: An Overload Problem? Plos One,10(12). doi: /journal.pone Bloem, B. R., Marinus, J., Almeida, Q., Dibble, L., Nieuwboer, A., Post, B.,... Schrag, A. (2016). Measurement instruments to assess posture, gait, and balance in Parkinsons disease: Critique and recommendations. Movement Disorders,31(9), doi: /mds Keus, S., Nieuwboer, A., Bloem, B., Borm, G., & Munneke, M. (2009). Clinimetric analyses of the Modified Parkinson Activity Scale. Parkinsonism & Related Disorders,15(4), doi: /j.parkreldis

41 References Ziegler, K., Schroeteler, F., Ceballos-Baumann, A. O., & Fietzek, U. M. (2010). A new rating instrument to assess festination and freezing gait in Parkinsonian patients. Movement Disorders,25(8), doi: /mds Yang, W., Hsu, W., Wu, R., & Lin, K. (2016). Immediate Effects of Clock-Turn Strategy on the Pattern and Performance of Narrow Turning in Persons With Parkinson Disease. Journal of Neurologic Physical Therapy,40(4), doi: /npt Frazzitta, G., Maestri, R., Uccellini, D., Bertotti, G., & Abelli, P. (2009). Rehabilitation treatment of gait in patients with Parkinsons disease with freezing: A comparison between two physical therapy protocols using visual and auditory cues with or without treadmill training. Movement Disorders,24(8), doi: /mds Schlick, C., Ernst, A., Bo Tzel, K., Plate, A., Pelykh, O., & Ilmberger, J. (2015). Visual cues combined with treadmill training to improve gait performance in Parkinsons disease: a pilot randomized controlled trial. Clinical Rehabilitation,30(5), doi: / Abbruzzese, G., Marchese, R., Avanzino, L., & Pelosin, E. (2016). Rehabilitation for Parkinsons disease: Current outlook and future challenges. Parkinsonism & Related Disorders,22. doi: /j.parkreldis Lu, C., Huffmaster, S. L., Tuite, P. J., Vachon, J. M., & Mackinnon, C. D. (2017). Effect of Cue Timing and Modality on Gait Initiation in Parkinson Disease With Freezing of Gait. Archives of Physical Medicine and Rehabilitation. doi: /j.apmr