The sooner the better?!: Providing ankle-foot orthoses in the rehabilitation after stroke

In stroke, the blood circulation in the brain is affected, being either ischemic or hemorrhagic. Depending on the location of the lesion, the effects can widely vary. Initial walking function is limited in approximately two-third of the patients. A “drop-foot”, the inability to dorsiflex the foot, is estimated to be present in 20-30% of the people after stroke and causes foot-clearance problems during swing phase and also affects initial contact at the start of the stance phase. Insufficient foot-clearance is associated with high risks for stumbling and falling. Ankle-foot orthoses (AFOs) are commonly used to correct drop-foot after stroke and are reported to improve mobility and balance, ankle kinematics, walking speed, self-confidence and fear of falling after stroke. However, most studies reporting on AFOs after stroke included chronic stroke patients who were already provided with AFOs in daily life and were able to walk independently. The general aim of this thesis was to increase the understanding of the effects of providing AFOs early after stroke. The EVOLUTIONS-project was conducted, including a randomized controlled trial in which the effects of AFO-provision on two different time points in the rehabilitation after stroke were studied. Subjects were included within six weeks after stroke and randomized for AFO-provision at inclusion of the study (in week 1) or eight weeks later (in week 9). The subjects were provided with one of three commonly used types of off-the-shelf, non-articulated AFOs with variability in stiffness. Subjects randomized for delayed provision did not use an AFO in the first eight weeks of the study. Subjects were studied up to 17 weeks with (bi)weekly intervals. Follow-up measurements up to 26 and 52 weeks were included. Measurements included functional outcomes related to balance, walking and activities of daily life. Furthermore, gait kinematics of the affected lower limb, muscle activation patterns of the tibialis anterior muscle, and falls and near falls were studied. Results showed positive effects on functional outcomes, both when AFOs were provided early or delayed. After 26 weeks no differences in functional outcomes were found between both groups. However, the results suggest that early provision results in better outcomes in the first 11-13 weeks of the study. Ankle dorsiflexion significantly improved directly after AFO-provision, changing the ankle from a plantarflexion into a dorsiflexion angle at initial contact, foot-off and during swing. These results were obtained regardless of AFO-provision early or delayed after stroke. In general, knee, hip and pelvis angles did not change directly after AFO-provision. After 26 weeks, no differences in kinematics in any of the joint angles were found between the two groups. These kinematic results indicate that AFOs improved drop-foot, but did not influence movement patterns around pelvis and hip. Previous literature suggested that AFO-use might increase muscle weakness, and thereby could impede recovery. Therefore, the effects of AFO-provision on muscle activity of the tibialis anterior were assessed. Results showed that AFO-use reduced muscle activity during swing within a measurement session, compared to walking without AFO. However, 26 weeks use of an AFO did not affect tibialis anterior muscle activity during walking without AFO. Again, early or delayed AFO-provision did not affect the results. These results indicate that there is no need to fear negative consequences on tibialis anterior activity because of long-term AFO-use (early) after stroke. In addition, the effects on the occurrence and circumstances of (near) falls were studied using diaries. In case of an incident, the location, performed activity, possible injuries and whether the AFO was used. We found that subjects in the early group, who had already been provided with AFOs, fell significantly more often in the first eight weeks of the study, compared to the delayed group who had not yet been provided with AFOs. The majority of the falls in the early group in week 1-8 occurred without wearing the AFO. Falls mainly occurred during transfers and standing, during activities related to getting in/out bed, toileting and showering. The majority of the subjects had not yet reached an independent ambulation level at the time of the fall (Functional Ambulation Categories ≤3) and had low balance levels (Berg Balance Scale