Phillip A. Gribble

While research on chronic ankle instability (CAI) and awareness of its impact on society and health care systems has grown substantially in the last 2 decades, the inconsistency in participant or patient selection criteria across studies presents a potential obstacle to addressing the problem properly. This major gap within the literature limits the ability to generalize this evidence to the target patient population. Therefore, there is a need to provide standards for patient or participant selection criteria in research focused on CAI with justifications using the best available evidence. The International Ankle Consortium provides this position paper to present and discuss an endorsed set of selection criteria for patients with CAI based on the best available evidence to be used in future research and study designs. These recommendations will enhance the validity of research conducted in this clinical population with the end goal of bringing the research evidence to the clinician and patient.

Context: Dynamic postural control has gained popularity as a more useful assessment of function than static postural control. One measurement of dynamic postural control that has increased in frequency of use is the Star Excursion Balance Test (SEBT). Although the intrarater reliability of the SEBT is excellent, few authors have determined interrater reliability. Preliminary evidence has shown poor reliability between assessors. Objective: To determine interrater reliability using a group of investigators at 2 testing sites. A corollary purpose was to examine the interrater reliability when using normalized and nonnormalized performance scores on the SEBT. Design: Descriptive laboratory study. Setting: University research laboratory. Patients or Other Participants: A total of 29 healthy participants between 18 and 50 years of age. Intervention(s): Participants were evaluated by 5 raters at 2 testing sites. After participants performed 4 practice trials, each rater assessed 3 test trials in the anterior, posteromedial, and posterolateral reaching directions of the SEBT. Main Outcome Measure(s): Normalized and nonnormalized (leg-length) reaching distances were analyzed. Additionally, the mean and maximum values from the 3 test trials were analyzed, producing a total of 16 variables. Results: For all 16 measures, the interrater reliability was excellent. For the normalized maximum excursion distances, the intraclass correlation coefficients (1,1) ranged from 0.86 to 0.92. Reliability for the nonnormalized measurements was stronger, ranging from 0.89 to 0.94. Conclusions: When the raters have been trained by an experienced rater, the SEBT is a test with excellent reliability when used across multiple raters in different settings. This information adds to the body of knowledge that exists regarding the usefulness of the SEBT as an assessment tool in clinical and research practice. Establishing excellent interrater reliability with normalized and nonnormalized scores strengthens the evidence for using the SEBT, especially at multiple sites.

The International Ankle Consortium is an international community of researchers and clinicians whose primary scholastic purpose is to promote scholarship and dissemination of research-informed knowledge related to pathologies of the ankle complex. The constituents of the International Ankle Consortium and other similar organizations have yet to properly define the clinical phenomenon known as chronic ankle instability (CAI) and its related characteristics for consistent patient recruitment and advancement of research in this area. Although research on CAI and awareness of its impact on society and healthcare systems have grown substantially in the last 2 decades, the inconsistency in participant/patient selection criteria across studies presents a potential obstacle to addressing the problem properly. This major gap within the literature limits the ability to generalize this evidence to the target patient population. Therefore, there is a need to provide standards for patient/participant selection criteria in research focused on CAI, with justifications using the best available evidence. J Orthop Sports Phys Ther 2013;43(8):585–591. doi:10.2519/jospt.2013.0303

Hough previous study has investigated the reliability of FMS, no current research has examined intrarater reliability or how clinical experience plays a role in the reliability of this tool. In this controlled laboratory study design, repeated measures were used to investigate how experience using the FMS and clinical experience as an athletic trainer (AT) affects the intrarater reliability of FMS testing. Before the data collection, 3 individuals recruited from the university community provided signed informed consent to serve as videotaped models performing the FMS test. The participants (raters) in the study, with different levels of FMS and clinical experience, viewed each of the 3 videotaped models and rated the video models on each exercise of the FMS according to the script that was presented by one of the study investigators. A week later, the participants watched the same videos again, in a different randomized order, and rated each video model on each exercise. After the scores from the participants were collected from both sessions, the intersession scores of the FMS were examined to establish intrarater reliability of all the participants. Additionally, the intrarater reliability of different groups of clinicians and students was compared to make inferences about the influence of clinical experience as an AT along with previous experience using the FMS. The ATs with at least 6 months of experience using the FMS (ATExp group) had the strongest intrarater reliability [intraclass correlation coefficients, ICC (2,1): 0.946], followed by the AT group with moderate reliability [ICC (2,1): 0.771]. This study indicates that intrarater reliability is strong and seems to strengthen when the individuals have experience using the FMS in addition to clinical experience....

Context: A dynamic postural-control task that has gained notoriety in the clinical and research settings is the Star Excursion Balance Test (SEBT). Researchers have suggested that, with appropriate instruction and practice by the individual and normalization of the reaching distances, the SEBT can be used to provide objective measures to differentiate deficits and improvements in dynamic postural-control related to lower extremity injury and induced fatigue, and it has the potential to predict lower extremity injury. However, no one has reviewed this body of literature to determine the usefulness of the SEBT in clinical applications.Objective: To provide a narrative review of the SEBT and its implementation and the known contributions to task performance and to systematically review the associated literature to address the SEBT's usefulness as a clinical tool for the quantification of dynamic postural-control deficits from lower extremity impairment.Data Sources: Databases used to locate peer-reviewed articles published from 1980 and 2010 included Derwent Innovations Index, BIOSIS Previews, Journal Citation Reports, and MEDLINE.Study Selection: The criteria for article selection were (1) The study was original research. (2) The study was written in English. (3) The SEBT was used as a measurement tool.Data Extraction: Specific data extracted from the articles included the ability of the SEBT to differentiate pathologic conditions of the lower extremity, the effects of external influences and interventions, and outcomes from exercise intervention and to predict lower extremity injury.Data Synthesis: More than a decade of research findings has established a comprehensive portfolio of validity for the SEBT, and it should be considered a highly representative, noninstrumented dynamic balance test for physically active individuals. The SEBT has been shown to be a reliable measure and has validity as a dynamic test to predict risk of lower extremity injury, to identify dynamic balance deficits in patients with a variety of lower extremity conditions, and to be responsive to training programs in both healthy people and people with injuries to the lower extremity. Clinicians and researchers should be confident in employing the SEBT as a lower extremity functional test.

Context: Hormonal fluctuation as a risk factor in anterior cruciate ligament injury has been investigated with conflicting results. However, the influence of hormone fluctuations on ankle laxity and function has not been thoroughly examined. Objective: To examine the potential hormone contributions to ankle laxity and dynamic postural control during the preovulatory and postovulatory phases of the menstrual cycle using an ankle arthrometer and the Star Excursion Balance Test in healthy women. The cohort group consisted of male control participants. Design: Cohort study. Setting: Research laboratory. Patients or Other Participants: Twenty healthy women (age = 23.8 ± 6.50 years, height = 163.88 ± 8.28 cm, mass = 63.08 ± 12.38 kg) and 20 healthy men (age = 23.90 ± 4.15 years, height = 177.07 ± 7.60 cm, mass = 80.57 ± 12.20 kg). Intervention(s): Ankle stability was assessed with anterior-posterior and inversion-eversion loading. Dynamic postural control was assessed with the posteromedial reaching distance of the Star Excursion Balance Test. Main Outcome Measure(s): Female participants used ovulation kits for 3 months to determine the time of ovulation; during their preovulatory and postovulatory phases, they were tested in the laboratory with an ankle arthrometer and the Star Excursion Balance Test. Male participants were tested on similar dates as controls. For each dependent variable, a time by side by sex repeated-measures analysis of variance was performed. Statistical significance was set a priori at P < .05. Results: For anterior-posterior laxity, a side main effect was noted (F_1,38 = 10.93, P = .002). For inversion-eversion laxity, a sex main effect was seen (F_1,38 = 10.75, P = .002). For the posteromedial reaching task, a sex main effect was demonstrated (F_1,38 = 8.72, P = .005). No influences of time on the dependent variables were evident. Conclusions: Although women presented with more ankle inversion-eversion laxity and less dynamic postural control, hormonal fluctuations during the menstrual cycle (preovulatory compared with postovulatory) did not affect ankle laxity or dynamic postural control, 2 factors that are associated with ankle instability.

Article Citation: Phillip A. Gribble (2011) Commentary. Journal of Athletic Training: Sep/Oct 2011, Vol. 46, No. 5, pp. 468-469. https://doi.org/10.4085/1062-6050-46.5.468

Chronic ankle instability (CAI) has been previously associated with deficits in dynamic stability and proximal joint neuromuscular alterations separately, but it is unclear how the two factors relate. The purpose of this investigation was to examine the contributions of lower extremity kinematics during an assessment of dynamic stability in subjects with CAI. Thirty-eight subjects were divided equally into those with and without unilateral CAI. Subjects performed 10 single-limb jump landings on each limb. Kinematic position 100 ms pre-impact as well as peak and time-to-peak kinematic position post-impact were recorded for ankle plantar flexion, knee flexion and hip flexion. Ground reaction force data in the A/P and M/L directions were used to calculate the resultant vector time to stabilization (RVTTS). For the RVTTS data, a significant main effect (P=0.03) revealed that the CAI group had significantly reduced dynamic stability. For knee flexion pre-impact, a significant main effect for group (P=0.005) demonstrated that the CAI group prepared to land with less knee flexion than the Control group. Decreased knee flexion angle in preparation to land was apparent in the CAI group, and may play a role in the diminished dynamic stability in CAI subjects.