Description

The purpose of the study is to determine the effects of real-time gait-training interventions along with a home exercise program (intervention group) on biomechanical and patient-reported outcome measures of pain and function in runners with leg pain as opposed to receiving a home exercise program alone (control group). All participants will report to the Exercise and Sport Injury Laboratory for a 60-minute baseline clinical assessment performed by a blinded assessor to determine hip, knee, foot and ankle strength, range of motion, and alignment using valid and reliable measurement techniques. Participants will also perform a series of functional movement assessments while an assessor records frontal and sagittal camera views in order to determine lower extremity dynamic alignment. The functional assessments will include the star excursion balance test (SEBT), a lateral step-down, a single-leg squat to 45 degrees of knee flexion, and a treadmill gait assessment. The movement screens will be use to form criteria-based home exercise programs, such that a blinded assessor will evaluate the videos and categorize patients into varus, valgus, or neutral alignment groups. Participants will receive exercises tailored to these descriptions. Further, the static alignment measurements will be used to determine if lower extremity stretches are warranted.

Following the first baseline visit, participants will return to the lab for a second baseline visit to complete an indoor, instrumented gait analysis using a motion capture system. Participants will also become oriented to the RunScribe wearable sensors and associated phone application, and will perform a brief outdoor run at their preferred speed to calibrate the sensors. Participants will receive their home exercise prescription with supplemental videos to take home with them to ensure adequate understanding of the target exercise performance. Participants will then be randomly assigned to one of two groups: 1) sensor-based feedback with home exercises (intervention group), or 2) home exercises alone (control group). The randomization sequence will be created a priori with a random-number generator stratified by sex, and allocation will be placed in a sealed opaque envelope by the graduate student mentor to intentionally blind the study coordinator conducting the interventions.

Participants in the intervention group will receive a Garmin wristwatch to facilitate the gait-training feedback, and will be oriented to the procedures during 10 minutes of running on an indoor treadmill in the presence of the study coordinator to ensure adequate understanding and integration of the feedback. The RunScribe sensors will facilitate the feedback by providing real-time metrics on the Garmin watch face using a custom application. Contact time will be the central focus of the intervention; participants will receive a vibro-tactile alert to remain below the identified contact time cut-off based on preliminary data.

Regardless of group allocation, participants will be instructed to maintain a running log within the RunScribe phone application to track activity adherence, details of runs that are recorded by the sensors, and report pain 1-10 experienced before, during, and after runs. All participants will be asked to perform their interventions twice per week. Participants will be encouraged to maintain other normal activities in addition to the interventions.

During the intervention period, all participants will return to the lab once per week to determine if exercise progressions are warranted based using specific performance-based scoring criteria. These decisions will be made by an assessor blinded to group allocation. The intervention group participants will then check in with the unblinded study coordinator to receive instructions on gait-training feedback progressions. The intervention will follow a volume-based faded feedback design.

At the midpoint of the study, all participants will complete Visual Analog and Global Rating of Change scales to track self-reported recovery. At the end of the intervention period, all participants will be re-assessed by the same blinded assessor using the same baseline measures to determine changes in lower limb alignment, strength, flexibility, and functional movement patterns. The indoor gait assessment and calibration run performed at the second baseline visit will be repeated at this follow-up timepoint while all participants wear the RunScribe sensors. Participants will also repeat Visual Analog Pain and Global Rating of Change scales to assess self-reported recovery. The investigators will then be able to determine if contact time feedback delivered in the field effectively decreases contact time after feedback compared to baseline and compared to the control group, determine if contact time feedback delivered in the field carries over to other gait outcomes in the intervention group after gait-training compared to baseline and the control group, and assess if pain decreases and function increases after gait-training compared to baseline and to a greater extent than the control group.