Post-Concussion Musculoskeletal Injury Risks

OTHER

Post-Concussion Neuromuscular Function and Musculoskeletal Injury Risk Assessment

Participants will complete a comprehensive biomechanical and neuromuscular assessments to elucidate the underlying neuromuscular control mechanisms that may contribute to increased MSKI risk following concussion. Participants will also complete a battery of self-report psychosocial measures. Biomechanical Dynamic Movement Assessments: * Jump-Landing * Single Leg Hop * Anticipated Cut * Gait - Single Task * Gait - Dual Task Strength and Voluntary Muscle Activation Assessments: * Interpolated Twitch Technique * Muscular Ramp Contraction Sensory assessments: * Proprioception - Closed Chain * Passive Joint Repositioning * Light Touch Sensation Patient Reported Outcomes: * Self-Reported Musculoskeletal Injuries * National Institutes of Health Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function * PROMIS Pain Interference * PROMIS Depression * PROMIS Anxiety * Brief Resilience Scale (BRS) * Tampa Scale of Kinesiophobia (TSK-11)

Changes in Jump-Landing Kinematic and Kinetic Measures

Time frame: Initial testing after reporting asymptomatic post-concussion, 6-Weeks post-initial testing, and 12-Weeks post-initial testing.

The participant will stand on a 30cm tall box, set at a distance that is equal to 50% of the participant's height behind a set of force platforms. Once the participant receives a visual stimulus, he/she will jump so that both feet leave the box at the same time. Upon landing the participant will immediately jump vertically for maximal height. Participants will complete 5 jump-landings. Whole body biomechanics will be collected and kinematic and kinetic measures will be identified at initial ground contact ("initial contact"), the peak angle ("max") during the "landing phase" of the initial landings of the jump-landing, and the difference between these angles ("displacement").

Changes in Single Leg Hop Kinematic and Kinetic Measures

Time frame: Initial testing after reporting asymptomatic post-concussion, 6-Weeks post-initial testing, and 12-Weeks post-initial testing.

The participant will stand on a 30cm tall box, set at a distance that is equal to 50% of the participant's height behind a set of force platforms. Once the participant receives a visual stimulus, he/she will jump so that both feet leave the box at the same time. The participant will jump off the box and land on a single leg with hands on hips. Participants will be instructed to come to a stable position as quickly as possible upon landing. Participants will perform 5 single leg hop trials on each leg (10 total trials). Whole body biomechanics will be collected and kinematic and kinetic measures will be identified at initial ground contact ("initial contact"), the peak angle ("max") during the "landing phase" of the initial landings of the single leg-hop, and the difference between these angles ("displacement").

Changes in Anticipated Cut Kinematic and Kinetic Measures

Time frame: Initial testing after reporting asymptomatic post-concussion, 6-Weeks post-initial testing, and 12-Weeks post-initial testing.

The participant will stand on a 30cm tall box, set at a distance that is equal to 50% of the participant's height behind a set of force platforms. Once the participant receives a visual stimulus, he/she will jump so that both feet leave the box at the same time. The participant will jump off the box and land on a single leg. Immediately upon landing, the participant will cut at a 45° angle (marked with tape on floor) in the direction provided by the study team prior to the trial (cut towards dominant = land on non-dominant foot; cut towards non-dominant = land on dominant foot). Participants will complete 5 trials cutting in each direction (10 total trials). Whole body biomechanics will be collected and kinematic and kinetic measures will be identified at initial ground contact ("initial contact"), the peak angle ("max") during the "landing phase" of the initial landings of the anticipated cutting tasks, and the difference between these angles ("displacement").

Changes in Single-Task Gait Kinematic and Kinetic Measures

Time frame: Initial testing after reporting asymptomatic post-concussion, 6-Weeks post-initial testing, and 12-Weeks post-initial testing.

Participants will complete over-ground gait trials at self-selected walking speed. Participants will start approximately 3m in front of the force platforms so that he/she is at a steady walking speed by the time the participant's foot makes contact with a force platform. No verbal instructions will be provided to indicate that clean foot strikes are required, and participants will be instructed to look straight ahead while walking (i.e., minimizing "targeting"). Participants will complete 5 gait trials so that each foot makes contact with the force platform (10 total trials) for both tasks. Gait velocity, center of mass displacement, and center of mass velocity will be collected from these tasks.

Changes in Dual-Task Gait Kinematic and Kinetic Measures

Time frame: Initial testing after reporting asymptomatic post-concussion, 6-Weeks post-initial testing, and 12-Weeks post-initial testing.

Participants will complete over-ground gait trials as well as gait tasks under a dual-task condition at self-selected walking speed. Participants will start approximately 3m in front of the force platforms so that he/she is at a steady walking speed by the time the participant's foot makes contact with a force platform. No verbal instructions will be provided to indicate that clean foot strikes are required, and participants will be instructed to look straight ahead while walking (i.e., minimizing "targeting"). During dual-task conditions participants will complete Serial Sevens, Serial Nines, etc. Participants will start counting at a randomly generated number between 80 and 120 and will count backwards by the designated denomination. Participants will complete 5 gait trials so that each foot makes contact with the force platform (10 total trials) for both tasks. Gait velocity, center of mass displacement, and center of mass velocity will be collected from these tasks.

Changes in Interpolated Twitch Technique Measurements

Time frame: Initial testing after reporting asymptomatic post-concussion, 6-Weeks post-initial testing, and 12-Weeks post-initial testing.

Participants will be seated in the dynamometer so that the axis of rotation of the participants' dominant knee coincides with the servomotor. Participants will be secured to the chair using seat belts along the chest, waist, and ankle. Adhesive stimulating electrodes will be placed on the skin overlying the distal vastus medialis muscle and proximal vastus lateralis muscle of the thigh on the dominant leg and will be controlled by electrical stimulators. Participants will perform a maximal voluntary isometric contraction (MVIC). During the MVIC, the muscle group will be stimulated with a paired-pulse stimulation, and the increase in torque over the MVIC level (i.e., interpolated twitch torque \[ITT\]) will be recorded. Following the MVIC, the paired-pulsed stimulation will be administered again (twice) to the relaxed muscle to determine peak electrically-evoked twitch torque (EET).

Changes in Muscular Ramp Contraction Measurements

Time frame: Initial testing after reporting asymptomatic post-concussion, 6-Weeks post-initial testing, and 12-Weeks post-initial testing.

Participants will be seated in the dynamometer so that the axis of rotation of the participants' dominant knee coincides with the servomotor. Participants will be secured to the chair using seat belts along the chest, waist, and ankle. Adhesive stimulating electrodes will be placed on the skin overlying the distal vastus medialis muscle and proximal vastus lateralis muscle of the thigh on the dominant leg, and will be controlled by electrical stimulators. Participants will perform three maximal voluntary isometric contractions (MVIC). The maximal voluntary muscle torque will be determined from this initial test and then used to create a ramping protocol in which the participant will ramp from 20 -100% maximal voluntary contraction over a 2.5 second period.

Changes in Closed-Chain Proprioception

Time frame: Initial testing after reporting asymptomatic post-concussion, 6-Weeks post-initial testing, and 12-Weeks post-initial testing.

The participant will stand with feet shoulder-width apart, feet (toes) pointed anteriorly, heels on the floor, and hands clasped in front of the participants chest. Participants will be asked to squat in a deep, slow, and controlled manner, to what they believe is 60-degrees of knee flexion and to hold that position for 5 seconds. Participants will then return to a full, upright position, march in place 10 times (5 each leg), and regain the original starting position. Participants will then be asked to replicate the same knee joint angle as they did in their initial trials. Participants will perform 3 trials following the initial trial (4 total trials).

Changes in Passive Joint Repositioning

Time frame: Initial testing after reporting asymptomatic post-concussion, 6-Weeks post-initial testing, and 12-Weeks post-initial testing,

Participants will be assessed using the passive motion and direction threshold method on a research dynamometer that passively moves the participant's dominant leg until the minimal detectable change in joint angle is perceived. Participants will be secured to the dynamometer while blindfolded and listening to static noise through headphones to eliminate movement cues. Initial starting positions will be 10° and 125° of knee flexion while the dominant knee will be passively moved at 5°/sec in either flexion or extension directions. The participant will be instructed to hit the "stop" button on the dynamometer once he/she perceives any movement, locking the dynamometer moment arm from moving and while the joint angle is recorded. Participants will perform 2 trials for each range (9 total trials).

Changes in Light Touch Sensation

Time frame: Initial testing after reporting asymptomatic post-concussion, 6-Weeks post-initial testing, and 12-Weeks post-initial testing.

Participants will be assessed using Semmes-Weinstein Monofilaments via a "4-2-1" stepping protocol using 20 force-calibrated nylon threads to assess sensory detection thresholds. Participants will lay prone on a treatment table, with their shoe and sock off of their dominant foot, listening to static noise through headphones, while the threads are applied until a "C" shaped bend occurs and is held for 1 second. The threads will be applied using a standard "4-2-1" stepping protocol for one trial. The light touch sensation main outcome measure is the diameter of the thread on the final application.

Changes in Self-Reported Musculoskeletal Injuries

Time frame: Monthly, through study completion (an average of 1 year)

Participants will report all of their previous MSKI sustained within 1- year prior to enrollment into the study and any "severe" MSKI they have sustained that resulted in 3 or more consecutive weeks of missed physical activity. Participants will also self-report if they sustain any new MSKIs during the study follow-up period. MSKIs will be operationally defined as: 1) a MSKI that required the participant to seek medical attention from a healthcare provider; or 2) a MSKI that required the participant to not participate in normal physical activity for 3 or more consecutive days. The following information will be self-reported for each injury: 1) date of injury; 2) activity at the time of injury; 3) mechanism of injury (overuse, traumatic); 4) if the injury is recurrent (i.e., previously experienced); and 5) if the MSKI resulted in less than or more than 1 week of missed or altered physical activity.

Changes in NIH-PROMIS Physical Function

Time frame: Monthly, through study completion (an average of 1 year)

Physical Function measures an individual's self-reported capabilities rather than his/her actual performance of physical activities. The assessment includes functioning of an individual's upper and lower extremities and neck and spine across a variety of activities.

Changes in NIH-PROMIS Pain Interference

Time frame: Monthly, through study completion (an average of 1 year)

Pain Interference measures an individual's self-reported consequences of pain on one's life over the past 7 days. This includes the extent to which pain hinders social, cognitive, emotional, physical, and recreational activities. Pain Interference also incorporates items that assess sleep and enjoyment of life.

Changes in NIH-PROMIS Depression

Time frame: Monthly, through study completion (an average of 1 year)

Depression measures an individual's self-reported negative mood, views of self, social cognition, and decreased positive affect and engagement over the past 7 days.

Changes in NIH-PROMIS Anxiety

Time frame: Monthly, through study completion (an average of 1 year)

Anxiety measures an individual's self-reported fear, anxiousness, hyperarousal, and somatic symptoms related to arousal (e.g., racing heart) over the past 7 days.

Changes in the Brief Resilience Scale (BRS)

Time frame: Monthly, through study completion (an average of 1 year)

A patient's psychological resiliency, their ability to "bounce back or recover from stress" may mediate health outcomes. Psychological resiliency has been associated with patient outcomes following shoulder stabilization surgery within a military population. Individuals who were more resilient had better outcomes (i.e., less time on limited duty status, less attrition from military service) than individuals who were non-resilient. The BRS has moderate test-retest reliability (ICCrange = 0.62-0.69) and has been validated against a number of different scales that measure various aspects of psychological resilience (rrange = -0.68-0.69).

Changes in the Tampa Scale of Kinesiophobia

Time frame: Monthly, through study completion (an average of 1 year)

The Tampa Scale of Kinesiophobia (TSK-11) measures pain-related fear of movement and re-injury. Kinesiophobia is an important factor in determining who will successfully RTD/A following a musculoskeletal injury. Kinesiophobia may impact sensorimotor function and movement quality in dynamic environments, potentially increasing musculoskeletal injury risk.

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