Elsevier

Gait & Posture

Volume 49, September 2016, Pages 86-89
Gait & Posture

Full length article
Reliability and responsiveness of gait initiation profiles in those with chronic ankle instability

https://doi.org/10.1016/j.gaitpost.2016.06.022Get rights and content

Highlights

  • Changes in central organization of movement can be assessed with gait initiation.

  • Gait initiation measurements demonstrated good-to-excellent reliability.

  • Its recommended gait initiation be used to evaluate the effect of an intervention.

Abstract

Individuals with chronic ankle instability (CAI) have demonstrated deviations in gait initiation (GI) compared to healthy individuals. However, the intersession reliability of GI measures remains unknown in this population. The objective of this study was to determine the reliability and responsiveness of GI measures between two testing days in those with CAI. Twelve individuals with CAI volunteered. Participants performed barefoot GI on a force plate which captured center of pressure (COP). Data was collected on two separate occasions separated by one week. The GI profile was separated into three phases (S1, S2, and S3). S1 began from the deviation of normal balanced standing to the most posterolateral displacement under the stepping limb. S2 began from the end of S1 to the maximum medial position under the stance foot. S3 began at the end of S2 and continued until the vertical ground reaction force dropped below 100 N. COP displacement (cm) was calculated as the sum of resultant vectors of the medial-lateral and anterior-posterior excursions for adjacent COP data points within each phase. The averages of 5 trials were used for analyses. Intraclass correlation coefficients (ICC(2,5)), standard error of measurement, and minimum detectable change (MDC) were calculated to determine reliability and responsiveness. S1, S2, and S3 displacement values were highly reliable between days (ICC(2,5) ≥0.76) with the exception of anterior-posterior S1 and medial-lateral S3. MDC values were relatively small (0.6–2.2 cm). GI can be reliably assessed in those with CAI which is important for identifying interventions to alter GI profiles in these individuals.

Introduction

Ankle sprains are common injuries in physically active populations [1]. Up to 75% of individuals who suffer a lateral ankle sprain may develop chronic ankle instability (CAI) [2]. CAI is characterized by an initial ankle sprain followed by repetitive future ankle sprains and the recurrent sensation of “giving way” [3]. Individuals with CAI are more likely to experience long-term consequences such as post-traumatic ankle osteoarthritis [4] and decreased health-related quality of life [5], [6]. Therefore, CAI is a common sequelae of lateral ankle sprains with implications that extend beyond the disability associated with acute bouts of joint trauma.

Several functional and mechanical impairments have been identified as contributing factors to CAI including alterations in sensorimotor function [7], [8]. Sensorimotor alterations include deficits in postural control and deviations in gait [3]. The sensorimotor alterations associated with CAI are thought to be caused by alterations in the feedback mechanisms of motor control because of damage to afferent receptors located in the ankle joint. However, alterations in single-limb stance postural control have been identified in the uninjured limb [9] of individuals with unilateral CAI suggesting there may be alterations in feed-forward mechanisms in these patients. Additionally, individuals with CAI have demonstrated predictable muscle recruitment during differing conditions where healthy individuals adapted to the conditions by recruiting different muscles [10]. These alterations were identified during a transition from a double limb stance to single limb stance which may be similar to the transition that occurs during GI. Alterations in feed-forward mechanisms of motor control would indicate that those with CAI may exhibit detrimental changes in the central organization of executing a movement goal.

Alterations in the central organization of movement in individuals with CAI are supported by a study [11] which identified deviations in the gait initiation (GI) profile of these individuals. GI is the transition from a stable stance to a stable state of walking and has been thought of as a measure of postural control and global functioning of the feed-forward mechanism of the sensorimotor system. The goals of the initial phase of GI are to generate forward momentum and propulse the center of mass toward the initial stance limb. Hass et al. [11] determined that individuals with CAI tend to have less of a posterolateral shift in center of pressure (COP) at the beginning of GI. The initial decreased shift towards the posterolateral direction at the beginning of GI declines naturally with age and disability, but may also be decreased in individuals with a postural control deficit [12], [13], [14]. Individuals with CAI also demonstrate less of a shift towards the stance foot when shifting weight from the step foot to the stance foot [11]. This decrease could be indicative of a reduction in lateral stability in these individuals. Decreases in both of these shifts represent a more constrained sensorimotor system and alterations in the central organization of movement where healthy individuals may be able to better adapt and cope to different demands utilizing varying options to complete the movement goal.

Although GI impairments have been identified in individuals with CAI, the reliability of this assessment has not been examined in this population. Establishing the reliability of GI is essential to determine if changes in this aspect of function can be captured over time and following clinical interventions. Therefore, the purpose of this study is to determine the intersession reliability and responsiveness of GI measures in those with CAI.

Section snippets

Participants

Twelve participants with self-reported CAI (6 females and 6 males: age = 27.4 ± 4.5 years, height = 175.4 ± 10.8 cm, mass = 78.4 ± 12.1 kg) volunteered to participate. To be included, Participants reported a history of at least one previous ankle sprain and 2 episodes of a “giving way” sensation in the previous 3 months. Participants had to report a decrease in function due to their history of ankle sprains by scoring ≤90% on the Foot and Ankle Ability Measure (FAAM) and ≤80% on the FAAM-Sport. The means and

Results

Means and standard deviations, ICC(2,5), SEM, and MDC values for all measures can be found in Table 2. The COP displacement measures were highly reliable between Session-1 and Session-2 (ICC values ranging from 0.76 to 0.92) with the exception of ML displacement for S3 (ICC = 0.25) and AP displacement for S1 (ICC = 0.51).

Discussion

The primary finding of this investigation was GI can be reliably assessed between testing sessions in individuals with CAI. With the exception of ML displacement for S3 and AP displacement for S1, the reliability estimates for all other measures were greater than 0.76 indicating good-to-excellent reliability. The resultant displacement was reliable and stable for each phase and may therefore be the preferred measure. In addition, the MDC values for all measures were reasonable compared to the

Conclusions

The GI phases of people with CAI were identified with the combined use of visual inspection and an algorithm created to determine the timing of the events. By using these tools, the process of identifying the phases is reliable with only small amounts of change expected in these variables. Future research should be conducted to determine whether this measure of feed-forward processing of the sensorimotor system can differentiate individuals with and without a certain condition or detect changes

Conflict of interest

The authors have no conflicts of interest to report.

Funding

No funding was received in support of this project.

References (16)

There are more references available in the full text version of this article.

Cited by (9)

  • Postural phase duration during self-generated and triggered gait initiation in patients with chronic ankle instability

    2023, Science and Sports
    Citation Excerpt :

    All subjects performed gait initiation in two conditions (self-generated and triggered) and three directions (straight ahead: 0°, clockwise: +30°, and counter-clockwise: −30°). CAI participants used their involved limb as the initial stance limb, consistent with previous research [16,23] while the control group used their dominant limb as the initial stance limb in all trials. Each participant completed five trials of each combination of condition and direction.

  • Center of pressure excursion and muscle activation during gait initiation in individuals with and without chronic ankle instability

    2020, Journal of Biomechanics
    Citation Excerpt :

    Given the postural control impairments and muscle activation alterations present in those with CAI, the quantitative characterization of the APAs and muscular activity during GI may provide relevant information on the underlying motor control strategies that are altered in those with CAI. To date, several investigations have demonstrated that the COP trace (i.e. pattern of COP during GI) is altered in those with CAI relative to uninjured controls(Ebrahimabadi et al., 2017) and that the COP trace is highly reliable within CAI patients (Hartley et al., 2016). However, no investigation has quantified the neuromuscular mechanisms for these kinetic alterations.

  • Spatiotemporal and kinematic characteristics of gait initiation across a wide speed range

    2018, Gait and Posture
    Citation Excerpt :

    It is therefore important to be able to quantify spatiotemporal characteristics and kinematics of this movement to assess the impact of disability. Typically studies report that participants are asked to perform the task at ‘self-selected’ speed [1–5,8–10]. However, if both healthy adults and those with disability are asked to perform gait initiation at ‘self-selected’ speed it is possible, even likely, that different speeds will be used.

  • Decreased Anticipatory Postural Adjustments During Gait Initiation Acutely Postconcussion

    2017, Archives of Physical Medicine and Rehabilitation
    Citation Excerpt :

    Finally, in light of the recent findings potentially linking multiple concussions to later-life impairments, these potential central neurophysiological deficits should be further investigated.49-51 The 2 groups pretest GI APA performance was similar to previous reports for healthy young adults; however, the GI APA characteristics of participants with concussion closely resembled those of aging or neurologically diseased patient populations.30,32,52-55 Specifically, the mean posterior displacement of the COP during the preparatory phase for participants with concussion was only 2.59cm, a 54% reduction from pretest, and substantially lower than previous reports of older adults (range, 3.2–3.5cm) and comparable with patients with Parkinson disease (range, 2.5–2.9cm).30,32

View all citing articles on Scopus
View full text