Middle and Long Latency Cutaneous Reflexes During the Stance Phase of Gait in Individuals with and Without Chronic Ankle Instability.

Background/objectives: Lower limb cutaneous reflex amplitudes can modulate across gait, which helps humans adjust rhythmic motor outputs to maintain balance in an ever-changing environment. Preliminary evidence suggests people who suffer from repetitive ankle sprains and residual feelings of giving way demonstrate altered cutaneous reflex patterns in the gastrocnemius. However, before cutaneous reflex assessment can be implemented as a clinical outcome measure, there is a need to substantiate these early findings by measuring reflex amplitudes across longer latency periods and exploring the variability of reflexes within each subject.

Reliability of reflex measurements and perceived instability following cutaneous stimulation during gait.

Individuals with chronic ankle instability (CAI) exhibit a variety of sensorimotor deficits which contribute to long-term health risks and lower overall health-related quality of life. Recent literature finds abnormal cutaneous reflex characteristics and perceptions of instability during gait among those with CAI. These may serve as important patient-specific outcome measures in diagnosing and monitoring the condition, however, the test-retest reliability of these measurements is still undetermined.

Contralateral cutaneous reflex modulation during gait in individuals with and without chronic ankle instability.

Introduction: Chronic ankle instability (CAI), a common seqeula to ankle injury is characterized by a variety of sensorimotor deficits extending beyond the previously injured limb. Cutaneous reflexes have been identified as a potential contributor to these functional limitations with recent studies identifying alterations in reflex patterns following sural nerve stimulation among those with CAI. To date, no studies have measured cutaneous reflexes of the unaffected limb in this population, therefore, the objective of this study was to measure contralateral cutaneous reflexes during gait in individuals with unilateral CAI and healthy controls.

Perceived ankle instability and cutaneous reflex modulation during gait.

Cutaneous reflex modulation during rhythmic ambulation is an important motor control mechanism to help minimize stumbling following an unexpected perturbation. Previous literature found individuals with chronic ankle instability (CAI) experience altered reflex patterns compared to healthy controls. Considering CAI is characterized by intermittent feelings of ankle instability, researchers have speculated that these alterations are related to perceived instability.

The role of sural nerve reflexes during drop-landing in subjects with and without chronic ankle instability.

The purpose of this study was to investigate the functional role of cutaneous reflexes during a single-leg drop-landing task among healthy, neurologically intact adults, and to identify whether individuals with chronic ankle instability (CAI) demonstrate altered reflexes and subsequent ankle kinematics. All subjects were physically active adults and were categorized as control (n = 10, Male = 6, Female = 4) or CAI (n = 9, Male = 4, Female = 5) depending on whether they scored a 0 or ≥ 11 on the Identification of Functional Ankle Instability questionnaire, respectively. Subjects performed 30-40 single-leg drop-landing trials from a platform set to the height of their tibial tuberosity.