4.6 Vestibular Dysfunction
Vestibular dysfunction if commonly overlooked when diagnosing a traumatically brain-injured individual. Vertigo, balance problems, visual complaints (double vision, blurriness) and nausea are possible symptoms of vestibular injury. Mann and Black (2000) noted that the most common persisting vestibular symptom after TBI is positional vertigo (symptoms caused by head movement). Vertigo is a vestibular dysfunction caused by dysfunction of the vestibular nerve or the labyrinth (Shepard & Telian, 1995) and the inability of the central nervous system to effectively compensate for the dysfunction (Gurr & Moffat, 2001). Provoked vertigo manifests as either unilateral peripheral hypofunction, bilateral peripheral hypofunction or benign paroxysmal positional vertigo (Godbout, 1997). Although it is common for the spontaneous resolution of vertigo to occur within 6 months of onset, in the TBI population natural recovery is constricted due to the frequent combination of central and peripheral vestibular structure injury. Vestibular rehabilitation following TBI is therefore needed in order to promote vestibular adaptation and recovery. Vestibular rehabilitation post TBI generally employs techniques that have shown to decrease vestibular dysfunction in non TBI populations. Unfortunately, little research has examined whether or not these techniques are also effective for individuals with a TBI. Techniques which are typically used in vestibular rehabilitation are gaze stability exercises, vestibulo-ocular reflex gain adaptation, substitution exercises, habituation techniques and static and dynamic balance and gait exercises (Scherer & Schubert, 2009). The optimal recovery of vestibular dysfunction is thought to be based on selecting the appropriate vestibular exercises for a specific individual and progressing gradually through the assigned exercises while increasing difficulty and intensity (Wee, 2002).
Individual Studies
Table 4.18 Rehabilitation for the treatment of vertigo post ABI
| Author/ Year/ Country/ Study design/ PEDro & D&B Score |
Methods |
Outcome |
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Katz-Leurer et al., (2009) Israel RCT D&B=18 PEDro=7 |
N = 20 Children post- TBI (7 boys, 3 girls) or cerebral palsy (7 boys, 3 girls) were randomly assigned to control or experimental condition. Ages were 7-13 years old. Controls were instructed to continue with their regular daily activities. Children in the experimental group were instructed to continue with their regular daily activities and do a series of exercises at home 5 days a week for 6 weeks. The exercises were 1) sit-to-stand, 2) step-up, forward, L 3) step-up, forward, R 4) step-up, sideward, L 5) step-up, sideward, R. Three sessions of 1 minute each for every exercise, on a daily basis. The children were provided with a diary and were asked to keep a record of the number of sets and repetitions completed each day. |
No significant differences between groups at baseline were found. At the end of the intervention period, an increase of 3-4 cm in mean Functional Reach Test and a reduction of 1.6 ± 2.1 seconds in the Timed Up and Go Test were noted in the experimental group subjects and not in the control group. Both tests represented balance performance. All other outcomes (walking performance and muscle strength) had no significant differences between groups. Balance performance improvement in the experimental group was maintained 6-weeks post-intervention. After the intervention, the mean number of sit-to-stands and step-ups increased significantly in the experimental group. No significant reduction in performance was noted during the follow-up period. |
|
Ahn et al., (2011) South Korea Non-RCT D&B=15 |
N=144 Participants with benign paroxysmal positional vertigo (BPPV) either post-TBI (32, 18 men, 14 women, mean age = 52.9 ±11.2 years) or idiopathic (112, 44 men, 68 women, mean age = 55.3 ±15.9 years) were diagnosed with either posterior semicircular canal - BPPV (PSC) using the Dix-Hallpike Test or horizontal semicircular canal-BPPV (HSC) using the supine head-turning test. Subjects were treated with the Epley maneuver if diagnosed with PSC and a modified 4th step of the Semont maneuver (head shaking) if diagnosed with HSC. The subjects were re-evaluated for BPPV 3-5 days post-treatment. Treatments were repeated until nystagmus and positional vertigo were absent. Subjects were further re-examined 3 months and 6 months after testing negatively for vertigo. | Post-traumatic patients received on average 1.8 treatment sessions in order to resolve vertigo. 19/32 post-traumatic patient's BPPV resolved after one treatment. 94/105 idiopathic subjects had resolved BPPV after one treatment. The mean number of treatment sessions required by patients in the post-traumatic group was significantly greater than the mean number required by idiopathic patients. Recurrence rate did not differ between groups. |
|
Dault and Dugas (2002) Canada Pre/Post D&B = 14 |
N=8TBI patients (mean age 29.6, time since injury: 6-106 months) completed an individualized 12-week training program (TP) combining aerobic dance, and slide and step training for 30 minutes twice a week compared to traditional muscular training (TMT) for 60 minutes twice a week for 12 weeks. Postural imbalance was evaluated by using the Clinical Test for Sensory Interaction in Balance (CTSIB). Coordination deficits evaluated by using a jumping jack movement. | At the end of therapy, participants’ vertigo symptoms and somatic anxiety had significantly decreased compared with baseline and pre-test (p<0.01). Significant reduction in vertigo rating scale scores from baseline and pre-test to the post-test and follow up (p<0.01). Five point vertigo rating scale indicated that vertigo provided almost no problem at the end of the therapy. Following therapy, participant’s performance on the vertigo exercises had significantly improved. Patients were able to exercises significantly faster (p<0.01) with significant lower rating of dizziness (p<0.01). Post-test levels of postural sway on the sway monitor (ability to balance on an unstable surface with eyes open) had significantly improved compared to pre-test levels (p=0.008). Significant improvements on the HAD (emotional distress) post-test values on the subscales of anxiety (p<0.05), depression (p<0.02) and total score (p<0.01) compared to pre-test values. No significant improvements noted on the VCQ (coping strategies) at assessment, and pre/post-test stage. Post-test Vertigo handicap levels (VHQ scores) significantly decreased compared to pre-test (p<0.01). |
|
Godbout (1997) Canada Single-case intervention D&B = 11 |
N=1 16 year-old male experiencing vertigo 6 months post-trauma, had sustained severe TBI (GCS = 5). Completed customized habituation training (HT) three times a day while in clinical setting (4 days/week) and twice a day while at home (3 days/week). Participant also completed vestibular rehabilitation in the clinical setting for 20 minutes/day to improve hand-eye coordination for gaze stabilization, balance retraining and conditioning exercises. Progress evaluated by the number of seconds the participant took to lie down from the long sitting position without provoking vertigo. | After the treatment phase, the time from sit-to-supine was significantly reduced (p<0.05). The transformed treated data of the treatment phase was not above the celeration line, which suggests the subject had a positive response to the treatment. Visual inspection of the data confirmed that the change due to treatment was maintained for a month past the end of the HT phase. |
|
Motin et al., (2005) Israel Post Intervention D&B = 11 |
N= 10 subjects (8 men, 2 women) withpost-TBI benign paroxysmal positional vertigo (BPPV) confirmed by Dix-Hallpike Test, mean time since injury 67 ±14 days, mean age 43 ±12 years. The examiner performed the Dix-Hallpike test to the affected side such that nystagmus and vertigo were elicited; this position was maintained for 1-2 minutes. The patient's head was then rotated 90ºto the opposite side and held for ~ 30 seconds. The subject was then asked to turn their head another 90ºto the unaffected side. This position was maintained for another 1-2 minutes and then the subject was assisted to sit-up | 6/10 subjects had resolved positional nystagmus and vertigo following a single particle repositioning maneuver. 9/14 (64%) affected ears had resolved positional nystagmus and vertigo following a single particle repositioning maneuver. The other four subjects needed between 3 and 6 repeated treatments until their symptoms were completely resolved. |
|
Wee (2002) Singapore Case Study No Score |
N=1 16 year-old female with complaints of vertigo and postural instability three years post TBI (GCS=8). Habituation exercises (2-3 times a day), vestibular adaptation exercises, balance exercises (2 times a day) and a balance master training program were done for six weeks. |
After three weeks of treatment: the intensity and duration of vertigo was reduced, dynamic visual acuity (DVA) was improved, postural sway was reduced and the composite equilibrium score improved from 41 pre-treatment to 61.
After six weeks of treatment: subject no longer reported vertigo when she looked up to the right side (initial complaint), further improvement in DVA was observed, the composite equilibrium score (71) and the sensory organization test scores reached the age-matched normative range, the subject resumed all activities of daily living without any vertigo or blurred vision.
6 months post-treatment: the subject still experienced no vertigo. |
|
Gurr and Moffat (2001) |
N=18 subjects with vertigo due to acquired brain injury were assessed for vestibular disorder and referred to a vestibular rehabilitation program. Therapy consisted of a behavioral exposure program to movements and activities that provoked vertigo and anxiety in order to assist compensation of vestibular dysfunction and habituation to physical anxiety symptoms. |
At the end of therapy, participants’ vertigo symptoms and somatic anxiety had significantly decreased compared with baseline and pre-test (p<0.01). Significant reduction in vertigo rating scale scores from baseline and pres-test to the post-test and follow up (p<0.01). Five point vertigo rating scale indicated that vertigo provided almost no problem at the end of the therapy. Following therapy, participant’s performance on the vertigo exercises had significantly improved. Patients were able to exercises significantly faster (p<0.01) with significant lower rating of dizziness (p<0.01). Post-test levels of postural sway on the sway monitor (ability to balance on an unstable surface with eyes open) had significantly improved compared to pre-test levels (p=0.008). Significant improvements on the HAD (emotional distress) post-test values on the subscales of anxiety (p<0.05), depression (p<0.02) and total score (p<0.01) compared to pre-test values. No significant improvements noted on the VCQ (coping strategies) at assessment, and pre/post-test stage. Post-test Vertigo handicap levels (VHQ scores) significantly decreased compared to pre-test (p<0.01) |
D&B = Downs and Black (1998) quality assessment scale score.
Discussion
In children, a lower-limb motor-capability training program improved walking and balance performance; these benefits transferred to other activities of daily living such as sport participation and exercise routines (Katz-Leurer et al.,2008; Katz-Leurer et al., 2009). Compliance with at-home programs was shown to be maintained by program simplicity, therapist check-ins, written information about the program, and a personal diary used to record completed exercises (Katz-Leurer et al., 2009). In a small sample of adults, aerobic dancing and slide-and-step training improved balance and coordination in patients many years following TBI, suggesting that long-term improvement of vestibular dysfunction is possible with the appropriate program (Dault & Dugas, 2002). More research on the benefits of motor training in both the pediatric and the adult population are needed in order to confirm the wide-spread benefits of this intervention.
Two case studies have revealed vestibular improvements based on individualized training programs. Vertigo is alleviated, and both gaze stability and postural stability are improved because of a customized vestibular rehabilitation program in individuals with severe TBI (Wee, 2002). Customized programs which are specifically designed to reduce the unique vestibular dysfunction of a specific individual are more beneficial than generic programs (Wee, 2002). Vertigo can be reduced after only three weeks of therapy if it consists of repeated exposure to the positions which provoke vertigo and its related symptoms (Godbout, 1997; Wee, 2002). Since these results are based on case studies, they are not necessarily generalizable to the entire TBI population.
Habituation training is most effective for TBI patients when rehabilitation begins within one year of the onset of vertigo, a structured approach is used, adjustments of intensity and repetitions are made (as necessary), and positive social reinforcement is provided (Godbout, 1997). Patients with TBI suffering from benign paroxysmal positional vertigo (BPPV) should be specifically treated with repositioning maneuvers until complete resolution (Motin et al., 2005). Post-traumatic BPPV requires more treatment sessions than idiopathic BPPV; however, once the symptoms have been resolved recurrence rates are similar for both types of BPPV (Ahn et al., 2011). Gurr and Moffat (2001) added a cognitive aspect to vestibular rehabilitation. The authors attempted to restructure the maladaptive thoughts and belief patterns associated with the symptoms of provoked vertigo. Further research with larger sample sizes will be needed to conclude whether cognitive behavioural therapy for vestibular rehabilitation is more beneficial than the behavioural therapy typical of vestibular rehabilitation for patients with TBI.
Conclusions
There is Level 1 evidence suggesting that home based exercise programs do increase functional balance in children who have sustained an ABI or have been diagnosed with CP.
There is Level 4 evidence to support using a combined aerobic dancing, slide and step training program to reduce balance and coordination deficits post ABI.
There is Level 4 evidence from one SSI, that habituation training was beneficial in reducing provoked vertigo following a severe TBI.
There is Level 4 evidence that vestibular rehabilitation programs improve symptoms of vertigo in patients after a TBI.
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Home based exercise programs increase functional balance in children.
Aerobic dance, slide and step programs improve balance and coordination post ABI.
Habituation training helps reduce provoked vertigo resulting from an ABI.
A vestibular rehabilitation program is an effective method for improving symptoms of vertigo in patients following traumatic brain injury.
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