A sock for foot-drop: a preliminary study on two chronic stroke patients

Investigating the underlying biomechanical mechanisms leading to falls in long-term ankle-foot orthosis and functional electrical stimulator users with chronic stroke

BACKGROUND

Ankle-foot-orthoses (AFOs) and functional electrical stimulators (FES) are commonly prescribed to treat foot-drop in individuals with stroke. Despite well-established positive impacts of AFO and FES devices on balance and gait, AFO and FES-users still fall at a high rate.

OBJECTIVE

The objective of this study was to investigate 1) the underlying biomechanical mechanisms leading to a fall in long-term AFO and FES-users with chronic stroke and 2) the impacts of AFOs and FES devices on fall outcomes and compensatory stepping response of long-term users with chronic stroke.

METHODS

Fall outcomes as well as kinematics and kinetics of compensatory stepping response of 42 individuals with chronic stroke (14 AFO-users, 10 FES-users, 18 Non-users) were evaluated during trip-like treadmill perturbations. AFO and FES-users were evaluated with and without their device.

RESULTS

Chronic AFO and FES-users fell 2.50 and 2.77 times more than Non-users. The most robust differences between AFO/FES-users and Non-users were 1) Reduced capacity to stabilize the trunk through reduction in forward whole-body angular momentum and 2) diminished capability to prepare and generate a second step using the paretic leg. Provocatively, the removal of AFO and FES devices did not decease/increase falls or change kinematics.

SIGNIFICANCE

It is well-established that AFOs/FES devices have a positive impact on static balance and decrease community falls by increasing toe clearance thus preventing trips/stumbles. However, our results suggest that once a trip occurs, these devices do not adequately assist recovery of balance. Specifically, current AFO and FES devices do not assist with second step generation or trunk control. Future studies should explore new devices or training paradigms that target enhancing trunk control and paretic compensatory stepping to decrease falls in this population.

The Utility of Dynamic Movement Orthoses in the Management of Complex Regional Pain Syndrome-A Case Series

Complex regional pain syndrome (CRPS) is a relatively rare, but debilitating condition that may occur after limb or peripheral nerve trauma. Typical symptoms of CRPS include swelling, allodynia, hyperalgesia, and skin temperature changes. Although a variety of pharmacological and non-pharmacological approaches are commonly used in caring for individuals with CRPS, they are frequently ineffective and often associated with side effects and/or additional risks. Previously, elastomeric orthotic garments have been shown to decrease neuropathic pain, reduce edema, and increase proprioception, but no previous reports have described their use in treating CRPS. Accordingly, this case series describes our experiences using a Lycra-based, custom-fabricated Dynamic Movement Orthosis (DMO) as a novel treatment to reduce the symptoms of CRPS and promote function. Four patients were included in this case series, all of whom had very different causes for their CRPS, including a combat-related gunshot injury resulting in multiple foot fractures with a partial nerve injury, a post-metatarsophalangeal fusion, an L5 radiculopathy, and a case of post-lower leg fasciotomies. These four patients all reported subjective improvement in their pain, function, and exercise tolerance in association with their DMO use. All patients demonstrated reduced use of analgesic medications. The pre- and post-DMO lower extremity functional scale showed clinically significant improvement in the two patients for which it was obtained.