Upper Extremity Training for Improving Balance Control Post-Stroke

Postural balance control is based on complex mechanisms involving several sensory and motor systems. Maintaining postural equilibrium requires muscle activation to oppose the balance threats. Stroke may be associated with a variety of deficits, including impaired upper limb functions , poor postural stability, impaired reactive balance control, and delayed responses to external balance perturbations. Individuals with stroke are at high risk for falls in all post-stroke stages. Falls may have long-term serious consequences and can lead to more disability. Upper extremity movements have a relevant contribution in controlling balance and enhance the ankle and hip strategies for maintaining upright postural stability among healthy adults. Upper extremities movements also, constitute important elements in both equilibrium and protective reactions. Appropriate corrective responses of both the upper and lower extremities are essential to regain balance control and reduce the risk of falls. More studies are required to know about the impact of arm movements on postural balance control in individuals post-stroke. The purpose of this study is to investigate the effect of the improvement of the upper extremity functions on postural balance control in patients with stroke.

Stroke is defined as rapidly developing clinical signs of focal (or global) disturbance of cerebral function, leading to death, with no apparent cause other than that of vascular origin. It considered the biggest burden cause of disability all over the world, 16 million people suffer from a stroke every year with great economic and social repercussions. Following a stroke, a number of impairments may influence the patient's ability to perform functional activities. These include weakness, alterations in tone, sensory loss, uncoordinated response, reduced balance mechanisms, and walking problems. Upper limb involvement is usually more pronounced than the lower limb. The effects of stroke on the upper limb functions are common and a significant cause of long-term disability. Balance impairment is one of the most common deficits in patients post-stroke. After a stroke, balance abilities are reduced due to abnormal muscle activity and asymmetric posture. Impaired Balance not only increases the risk of falls but also adversely affects physical activity and social participation. The inﬂuence of arm movements on postural control only appears to be evident in case of impairs upper extremity functional performance. Arm movements play a functional role in postural stability during standing and walking. Arm and hand movements can also serve a protective role to prevent head injury in case of falling. Rehabilitation programs aiming for improving upper extremity impairments and improving balance performance can reduce the fall risk in individuals with stroke. Recently, virtual reality-based training exercises, are used to improve upper limb functions, balance, gait, and quality of life in stroke survivors. Many studies supported that virtual reality-based programs are suitable and have a potential value for patients with stroke. The purpose of this study is to investigate the impact of the improvement of the upper motor abilities by using virtual reality-based training on balance control in patients with chronic stroke.

Eligibility Criteria:
Inclusion Criteria:

The inclusion criteria were: adult participants aged 50 to 60 years with a confirmed diagnosis of chronic stroke (at least 6 months following the stroke incidence) secondary to ischemia or hemorrhage. The degree of spasticity of the affected upper limb ranged between 1, 1+ and 2 according to Modified Ashworth Scale. All participants were cognitively able to understand and follow instructions. All participants did not receive other treatments to improve the functions of the affected upper limb except study treatment. During the study, participants were not receiving other interventions specialized to improve postural balance control.

Exclusion Criteria:

The exclusion criteria were: any participant with a cognitive reduction (\< 23 points based on Mini-Mental State Examination scale). (15) Participants with ﬁxed muscle contractures, joints' stiffness, and who had major rotational malalignment in the affected upper and lower limbs. Participants with vestibular, and cerebellar problems were also excluded from this study. Other exclusion criteria were participants with: visual, auditory, and perceptual diseases/impairment, uncontrolled seizures, and those who received botulinum toxin (six months before the beginning of the study) or muscle-tone control medication (three months before the beginning of the study).