Influence of sensory integration training on postural instability in elderly with parkinsonian disease following stereotactic surgery

Background Impaired posture is strongly associated with function particularly in patients with parkinsonian disease (PD). Objective To detect the effect of sensory integration training on postural instability in elderly PD following stereotactic surgery. Patients and methods A total of 27 patients with idiopathic PD were assessed before and after 12 weeks by the postural stability test. They were randomly assigned into three groups: group I (sensory integration training), group II (stereotactic surgery), and group III (sensory integration training after 10 days postoperatively). Results There was significant improvement in group III more than in groups I and II. The percent of improvement of group III was higher concerning the overall stability index (48.86%, t=7.088 and P=0.0001(, anterior/posterior index (74.61%, t=21.240 and P=0.0001), and medial/lateral index (55.81%, t=14.014 and P=0.0001). Group III was superior to groups I and II (P=0.026 and 0.001, 0.040 and 0.0001, and 0.049 and 0.0001). Conclusion Sensory integration training improved postural stability in elderly with PD following stereotactic surgery.


Introduction
Parkinsonian disease (PD) is characterized clinically by postural instability [1]. Although it is primarily a disease of the elderly, some individuals have developed PD in their 30's and 40's [2].
Postural instability, probably the most relevant symptom, leads to a poor quality of life [3]. It is particularly challenging and difficult to treat as it does not respond well to dopaminergic therapy [4]. Several studies have examined possible ways of predicting falls, with previous occurrence of falls being one of the main predictors, and several motor factors including measures assessing postural stability [5].
Stereotactic surgery is a minimally invasive form of surgical intervention that makes use of a threedimensional coordinate system to locate small targets inside the body and to perform on them some action such as radiosurgery, stimulation, and ablation [6].

Study design
This was a randomized case-controlled trial with pretest-post-test experimental design. It was conducted in the outpatient clinic of Faculty of Physical Therapy, Modern University for Technology and Information, during the period from January 2018 to August 2018. Patients signed an informed consent form before their engagement. The study was approved by the Ethical Committee of Faculty of Physical Therapy, Cairo University.

Sample size
A generated sample size, using the G*Power software (version 3.0.10) (Germany), of at least seven participants per group would be required. Allowing for a 20% dropout rate, it was necessary to reach a total sample level of a minimum of 27 participants.
Participants were randomly assigned using a handpicked envelope.

Patients and methods
A total of 27 patients with PD were invited to participate in the study. Their age ranged from 60 to 70 years old (16 males and 11 females). The duration of illness ranged from 5 years till 16 years. Patients were stage three according to Modified Hoehn and Yahr (HY), as well as Schwab and England scales [7], and Mini Mental State Examination score was more than 23 [8].
Participants were randomly assigned into three groups, and each group included nine patients: group I (control group) received sensory integration training, group II underwent deep brain stimulation (DBS) through stereotactic surgery, and group III received sensory integration training after 10 days postoperatively to stereotactic surgery (as illustrated in Chart 1). Postural stability was estimated by measuring the overall stability index, anterior/posterior (AP) index, and medial/lateral (M/L) index [6] before and after 12 weeks using Biodex Balance System (Biodex Medical Systems Inc., Shirley, New York, USA).

Statistical analysis
Statistical analysis was done using statistical packages for the social sciences (SPSS) version 20 for Windows (SPSS, Inc., Chicago, Illinois, USA). Paired t-test was used to compare within each group and one-way analysis of variance test among three groups. Posthoc multiple comparison test (least significance difference) was used to examine the superior group. Significant level of probability was P value up to 0.05.

Procedure
(1) Testing procedures: (a) The postural stability tests: The patient's score assesses deviations from center [9]. It includes overall stability index (SI), (b) AP index, and (c) M/L index.
(2) Training procedures: Sensory integration training was done to improve both feedback and feed-

Chart 1
Chart describing the recruitment of patients.
forward postural reactions. Patients were asked to repeat exercises belonging to three different predetermined groups of exercises [13,14].  (Table 4 and Fig. 4).  I, II, and III, respectively, which indicated a significant improvement in group III more than in groups I and II (Fig. 5).

The superior group
Post-hoc multiple comparison test (least significance difference) indicated the superiority of group III on group I and II (P=0.026 and 0.001, 0.040 and 0.0001, and 0.049 and 0.0001) in overall stability index, AP stability index, and M/L. Stability index respectively. However, there was no superiority between groups I and II in all measures (P=0.190, 0.161 and 0.183 for overall stability index, AP stability index, and M/L stability index, respectively) ( Table 5).

Discussion
Improving postural stability has been documented in patients with PD [15][16][17]. So, the mean values of overall stability index were 1.54±0.47 in pretreatment result and became 2.21±0.07 in posttreatment result in group I (t=4.754 and P=0.001). Furthermore, the exercise-induced benefits on overall brain health, including increased blood flow and trophic factors and a stronger immune system, may help address the environmental need for neuroplasticity in the damaged brain [18][19][20]. This, in turn, results in significant improvement in the mean values of AP index from 0.60±0.11 to 1.69±0.42 in group I (t=6.927 and P=0.0001).
However, effective sensory integration training protocols to improve postural stability have not yet been established. A previous study found that exercise training improved postural stability and also led to documented neurochemical and neuroplastic changes that occurred after the exercise intervention [21], so the concurrent study found a significant increase in the Demographic data. Influence of sensory integration training on postural instability in elderly with PD Elshinnawy et al. 93

Figure 2
Overall stability index.
Furthermore, stereotactic surgery might be more effective [28][29][30][31]. Studies that used quantified gait analysis and dynamic posturography also confirmed our findings that stereotactic surgery can improve postural Instability and gait disorder [32,33]. However, its effects on PIGD are uncertain [34,35]. Based on the findings of this study, the mean values of overall stability index was 1.78±0.44 and became 2.30 ±0.23 in group II (t=3.139 and P=0.014).
The improvements in AP index values was changed from 0.77±0.13 to 1.79±0.58, in group II (t=5.070 and P=0.001). However, DBS may slow functional progression because patients are more active and exercising more after surgery.
In addition, there also is evidence that exercise may improve function without preserving dopaminergic neurons presumably through compensatory mechanisms. There is growing evidence that physical activity can curb the rate of motor function decline. This was noticed in this study by the mean values of M/ L index, which was 0.43±0.05 and became 0.56±0.07 (t=2.278 and P=0.048). Despite improvements in clinical ratings of PIGD immediately after DBS, patients tend to fall more [36].
Patients, both in group I and group II, were improved but still tend to fall, so it was the idea of adding group III, who received sensory integration training after 10 days postoperative to stereotactic surgery. Based on these findings, the mean values of overall stability index was 1.  Medial/lateral index. .049 and 0.0001) in overall stability index, AP stability index, and M/L stability index, respectively. Therefore, stereotactic deep brain surgery partially improved limb kinesthesia and could restore medication-induced reductions of short latency afferent inhibition, and physiotherapy can be considered as a possible treatment to correct or compensate for kinesthetic deficits [11]. Ongoing exercise and physical fitness should be highly encouraged for patients with PD who are at risk of physical deconditioning and fear of falling because it is Percentage of improvement. beneficial with regards to physical functioning, health-related quality of life, strength, balance, and gait speed [35].

Conclusion
Accordingly, the physical therapy program should include sensory integration training for improving postural instability following stereotactic surgery in elderly with PD.