A Review of Ankle Foot Orthotic Interventions for Patients with Stroke

Lower limb orthotic intervention is considered as an important element in the rehabilitation of the patients with stroke. Hemiplegic gait are widely used by clinicians to describe a pattern of limb movement and body posture for the patients with stroke. This gait pattern is dangerous to the patients as it is an unstable walking pattern and has a high risk of fall. Application of ankle foot orthosis is a generally accepted method among physicians and orthotists for treating the patients with such impaired gait to prevent foot drop in swing phase. It not only facilitates toe clearance to prevent fall but also promotes heel strike in early stance. This article reviews different types of ankle foot orthoses for the rehabilitation of the patients with stroke. Such information would be useful to clinicians and researchers in selecting and developing the most appropriate ankle foot orthosis to their patients with stroke based on individual needs. CEREBRAL VASCULAR ACCIDENT Cerebral Vascular Accident (CVA), also known as Stroke (International Classification of Disease 10 ICD10: 160-169), is the third leading cause of death in Hong Kong after cancer and heart disease. More than three thousands of people died in Hon Kong each year for this condition and the proportion of total registered deaths was 8.88% [1]. Most strokes (88%) are ischemic events, including thrombosis (50%), embolism (30%), and decreased systemic perfusion (8%), while other etiologies include intracerebral hemorrhage (9%) and subarachnoid hemorrhage (3%). In 2008, the estimated direct and indirect cost of stroke was $65.5 billion US dollars in United States of America [2]. GAIT PATTERN OF PATIENTS WITH STROKE Perry (1985) demonstrated that the range of ankle motion for normal subjects during walking is 10° of dorsiflexion to 15° of plantarflexion [3] but Lamontagne et al. (2002) reported that most of the patients with stroke had reduced dorsiflexion during swing phase of the affected side compared with the control values [4]. Bohannon et al. (1987 & 1991) suggested that achieving normal gait pattern and speed are usually the ultimate goal of rehabilitation for the patients with stroke. Muscle weakness, abnormal tone, sensory and visual deficits as well as decreased joint range are considered to be the important elements that lead to affect gait speed [5, 6]. Hemiplegic gait is widely used by clinicians to describe a pattern of limb movement and body posture for the patients with stroke [7]. The patients often had inadequate shock absorption at heel strike or even worse as absence of heel strike by forefoot contact (Figure 1), inability to generate force for push off to maintain forward propulsion, and inadequate excursion of the paretic limb during swing [8, 9].