Injury and Treatment Characteristics of Middle School-Aged Patients Under the Care of Athletic Trainers from 2010-2022: A Report from the Athletic Training Practice-Based Research Network.

CONTEXT: Exploring sports-related musculoskeletal injuries and treatment characteristics in middle school sports may help inform patient care decisions such as appropriate medical coverage. OBJECTIVE: To describe injury and treatment characteristics of middle school-aged athletes receiving care from athletic trainers within the Athletic Training Practice-Based Research Network (AT-PBRN). DESIGN: Descriptive study. SETTING: Middle school. PATIENT OR OTHER PARTICIPANTS: Middle school-aged athletes (n=1,011; male=503, female=506) with sports-related musculoskeletal injuries. MAIN OUTCOME MEASURE(S): Electronic patient records were analyzed from the AT-PBRN from 59 athletic trainers across 14 states between 2010-2022. Summary statistics (frequency, percentages, median, interquartile ranges [IQR]) were used to describe injury (age at injury, sex, sport, body part, diagnosis) and treatment characteristics (type of treatment, number of visits, number of procedures per visit). RESULTS: Football (17.7%, n=179), basketball (17.6%, n=178), and soccer (14.9%, n=151) reported the highest number of injuries. Ankle (17.2%, n=174), knee (16.5%, n=167), and head (14.1%, n=143) were the most common injury locations. Concussion (13.0%, n=131), ankle strain/sprain (12.4%, n=125), and thigh/hip/groin sprain/strain (11.1%, n=112) were the most reported diagnoses. Therapeutic exercise or activities (25.6%, n=1068), athletic trainer evaluation or re-evaluation (22.9%, n=957) and hot/cold packs (18.4%, n=766) were the most common services with a median of 2 visits (IQR=1-4) and 2 procedures (IQR=1-2) per visit. CONCLUSIONS: Football, basketball, and soccer reported the most musculoskeletal injuries for middle school-aged athletes. Concussions were the most frequent diagnosis, followed by ankle sprains/strains. Our findings are similar to prior investigations at high school and collegiate levels. Treatments at the middle school level were also similar to those that have been previously reported at the high school level with therapeutic exercise/activity, athletic trainer evaluation or re-evaluation, and hot/cold packs being the most common treatments. This information may be useful for informing patient care decisions at the middle-school level.

Trunk and shoulder kinematics of rowing displayed by Olympic athletes.

The purpose of this study was to assess the effects of stroke rate and sex on trunk and shoulder kinematics of Olympic athletes during rowing on an ergometer. Fifty-eight participants (31 females and 27 males) from the Chinese National Rowing Team were recruited. Trunk (i.e., the pelvis, lumbar and thoracic spine) and shoulder kinematics were measured using an inertial measurement unit system for three stroke rates (18, 26, and 32 strokes/min). Range of motion and angles at the catch and finish were assessed using mixed model ANOVA and correlation analyses with rowing power. Range of motion increased significantly at higher rates for both female and male athletes. This may be a strategy used by athletes when dealing with higher demand for power during training, because a greater range of motion with a longer stroke length could reduce the demand for force generation and possibly delay fatigue. Female rowers exhibited greater range of motion in the lumbar spine, thorax and shoulders than males due to more extended positions at the finish. The sex-related kinematic differences may be attributed to differences in body size, muscle strength and endurance. Practitioners are recommended to consider these factors when developing rowing techniques and providing training suggestions.

Participant-Level Analysis of the Effects of Interventions on Patient-Reported Outcomes in Patients With Chronic Ankle Instability.

CONTEXT: Intervention studies for chronic ankle instability (CAI) often focus on improving physical impairments of the ankle complex. However, using an impairments-focused approach may miss psychological factors that may mediate function and recovery. Patient-reported outcome (PRO) measures can be used to assess several dimensions of the health-related quality of life (HRQoL) and deliver enhanced patient-centered care. Therefore, the purpose of this investigation was to evaluate group-level improvements in HRQoL and treatment response rates following various interventions in patients with CAI. DESIGN: Cross-sectional. METHODS: Data from 7 previous studies were pooled by the chronic ankle instability outcomes network for participant-level analysis, resulting in 136 patients with CAI. Several interventions were assessed including balance training, gait biofeedback, joint mobilizations, stretching, and strengthening, with treatment volume ranging from 1 to 4 weeks. Outcome measures were PROs that assessed ankle-specific function (Foot and Ankle Ability Measure), injury-related fear (Tampa Scale of Kinesiophobia and Fear Avoidance Belief Questionnaire), and global well-being (Disablement in the Physically Active); the PROs assessed varied between studies. Preintervention to postintervention changes were evaluated using separate Wilcoxon signed-rank tests and effect sizes, and a responder analysis was conducted for each PRO. RESULTS: Significant, moderate to large improvements were observed in PROs that assessed ankle-specific function, injury-related fear, and global well-being following intervention (P < .001). Responder rates ranged from 39.0% to 53.3%, 12.8% to 51.4%, and 37.8% for ankle specific function, injury-related fear, and global well-being, respectively. CONCLUSIONS: Various interventions can lead to positive improvements in HRQoL in patients with CAI. Treatment response rates at improving HRQoL are similar to response rates at improving impairments such as balance, further reinforcing the need for individualized treatment approaches when treating a patient with CAI.

Effects of Midfoot Joint Mobilization on Perceived Ankle-Foot Function in Chronic Ankle Instability: A Crossover Clinical Trial.

CONTEXT: To investigate the effects of midfoot joint mobilization and a 1-week home exercise program, compared with a sham intervention, and home exercise program on pain, patient-reported outcomes, ankle-foot joint mobility, and neuromotor function in young adults with chronic ankle instability. DESIGN: Crossover clinical trial. METHODS: Twenty participants with chronic ankle instability were instructed in a stretching, strengthening, and balance home exercise program and were randomized a priori to receive either midfoot joint mobilizations (forefoot supination, cuboid glide, and plantar first tarsometatarsal) or a sham laying of hands on the initial visit. Changes in foot morphology, joint mobility, strength, dynamic balance, and patient-reported outcomes assessing pain, physical, and psychological function were assessed pre to post treatment and 1 week following post treatment. Participants crossed over to receive the alternate treatment and were assessed pre to post treatment and 1 week following. Linear modeling was used to assess changes in outcomes. RESULTS: Participants demonstrated significantly greater perceived improvement immediately following midfoot mobilization in the single assessment numeric evaluation (sham: 5.0% [10.2%]; mobilization: 43.9% [26.2%]; ß: 6.8; P < .001; adj R2: .17; Hedge g: 2.09), and global rating of change (sham: -0.1 [1.1]; mobilization: 1.1 [3.0]; ß: 1.8; P = .01; adj R2: .12; Hedge g: 0.54), and greater improved 1-week outcomes in rearfoot inversion mobility (sham: 4.4° [8.4°]; mobilization: -1.6° [6.1°]; ß: -6.37; P = .01; adj R2: .19; Hedge g: 0.81), plantar flexion mobility (sham: 2.7° [6.4°]; mobilization: -1.7° [4.3°]; ß: -4.36; P = .02; adj R2: .07; Hedge g: 0.80), and posteromedial dynamic balance (sham: 2.4% [5.9%]; mobilization: 6.0% [5.4%]; ß: 3.88; P = .04; adj R2: .10; Hedge g: 0.59) compared to the sham intervention. CONCLUSION: Greater perceived improvement and physical signs were observed following midfoot joint mobilization.

Evidence of Intrinsic Foot Muscle Training in Improving Foot Function: A Systematic Review and Meta-analysis.

OBJECTIVE: To critically assess the literature focused on strength training of the intrinsic foot muscles (IFM) and resulting improvements in foot function. DATA SOURCES: A search of electronic databases PubMed, CINHAL, Scopus, and SPORT Discus was completed between January 2000 to March 2022. STUDY SELECTION: Randomized control trials (RCTs) with an outcome of interest with at least two weeks of IFM exercise intervention were included. Outcomes of interest were broadly divided in to five categories of foot posture (navicular drop (ND) and Foot Posture Index (FPI)), balance, strength, patient-reported outcomes (PROs), sensory function, and motor performance. The PEDro scale was used to assess the methodological quality of included studies with two independent reviewers rating each study. Studies with a PEDro score greater than 4/10 were included. DATA EXTRACTION: Data from the included studies were extracted by two independent reviewers. These data included design, participant characteristics, inclusion and exclusion criteria, type of intervention, outcomes, and the primary results. Random effects meta-analysis was performed to analyze difference between intervention and control groups for each outcome when there were at least two studies. Standardized mean differences (SMD) describe effect size with a 95% confidence interval (SMD range). When the confidence interval crossed zero the effect was not significant. DATA SYNTHESIS: Thirteen studies were included and IFM exercise interventions were associated with decreasing ND (SMD range=0.37,1.83), and FPI (SMD range=1.03,1.69), improving balance (SMD range=0.18,1.86), strength (SMD range=0.06,1.52) and PROs for disability (SMD range=0.12,1.00) with pooled effect sizes favoring IFM intervention over control. There was no superiority of IFM exercises (SMD range=-0.15,0.66) seen in reducing pain. We could not perform meta-analysis for sensory function and motor performance as there was only study reporting each outcome, however, these results supported the use of IFM strength training. CONCLUSION: IFM strength training is helpful for patients in improving foot and ankle outcomes.

Association of Ankle Sprain Frequency With Body Mass and Self-Reported Function: A Pooled Multisite Analysis.

CONTEXT: Ankle sprains result in pain and disability. While factors such as body mass and prior injury contribute to subsequent injury, the association of the number of ankle sprains on body anthropometrics and self-reported function are unclear in this population. Therefore, the purpose of this investigation was to assess differences in anthropometric measurements and self-reported function between the number of ankle sprains utilizing a large, pooled data set. DESIGN: Cross-sectional. METHODS: Data were pooled from 14 studies (total N = 412) collected by the Chronic Ankle Instability Outcomes Network. Participants were categorized by the number of self-reported sprains. Anthropometric data and self-reported function were compared between those who reported a single versus >1 ankle sprain as well as among groups of those who had 1, 2, 3, 4, and ≥5 ankle sprains, respectively. RESULTS: Those who had >1 ankle sprain had higher mass (P = .001, d = 0.33) and body mass index (P = .002, d = 0.32) and lower Foot and Ankle Ability Measure-Activities of Daily Living (P < .001, r = .22), Foot and Ankle Ability Measure-Sport (P < .001, r = .33), and Cumberland Ankle Instability Tool (P < .001, r = .34) scores compared to the single ankle sprain group. Those who had a single ankle sprain weighed less than those who reported ≥5 sprains (P = .008, d = 0.42) and had a lower body mass index than those who reported 2 sprains (P = .031, d = 0.45). CONCLUSIONS: Some individuals with a history of multiple ankle sprains had higher body mass and self-reported disability compared to those with a single sprain, factors that are likely interrelated. Due to the potential for long-term health concerns associated with ankle sprains, clinicians should incorporate patient education and interventions that promote physical activity, healthy dietary intake, and optimize function as part of comprehensive patient-centered care.

Utility of Gait Biofeedback Training to Improve Walking Biomechanics in Patients With Chronic Ankle Instability: A Critically Appraised Topic.

CLINICAL SCENARIO: Chronic ankle instability (CAI) is a condition that involves feelings of the ankle "giving way," pain, and decreased self-reported function. Individuals with CAI often demonstrate persistent biomechanical impairments during gait that are associated with repetitive lateral ankle sprains (LAS) and the development of early onset ankle posttraumatic osteoarthritis (OA). Traditional rehabilitation strategies have not successfully improved these reported aberrant gait biomechanics; thus, traditional rehabilitation may not effectively reduce the risk of recurrent LAS and ankle OA among individuals with CAI. Conversely, targeted gait training with biofeedback may be effective at decreasing the risk of recurring LAS and ankle OA if these rehabilitation strategies can promote individuals with CAI to develop a gait strategy that protects against subsequent LAS and ankle OA. CLINICAL QUESTION: Can targeted gait biofeedback interventions cause individuals with CAI to implement a walking gait pattern that is not associated with recurrent LAS and ankle OA? SUMMARY OF FINDINGS: Five studies assessed gait biofeedback interventions targeting plantar pressure and/or ankle kinematics involving visual biofeedback (n = 3), auditory biofeedback (n = 1), and haptic biofeedback (n = 1). Plantar pressure was medially shifted during a single session while receiving biofeedback (n = 2), immediately after biofeedback (n = 1), and 5 minutes after receiving biofeedback (n = 1) in 3 studies. One study demonstrated reduced ankle inversion after 8 sessions of biofeedback training. One study did not substantially improve plantar pressure while receiving visual feedback. CLINICAL BOTTOM LINE: Targeted gait training strategies appear effective in acutely altering gait biomechanics in individuals with CAI while receiving, and immediately after, biofeedback has been removed. Long-term outcomes are not currently established for gait training strategies in those with CAI. STRENGTH OF RECOMMENDATION: Limited evidence (grade B) suggests that targeted gait biofeedback strategies can alter specific CAI gait biomechanics to a strategy not associated with recurrent LAS, and ankle OA immediately, and after, multiple sessions of gait training.

Lower extremity joint kinematics of a simulated lateral ankle sprain after drop landings in participants with chronic ankle instability.

This study examined lower extremity joint kinematics in individuals with chronic ankle instability (CAI) and controls during unanticipated and anticipated single-leg drop landings onto a laterally inclined platform. Physically active adults with CAI 15 (n = 15) and controls (n = 15) performed an unanticipated and anticipated 30 cm single-leg drop landing onto a 20° laterally inclined platform. Three-dimensional ankle, knee and hip-joint kinematics were recorded 200 ms pre- to 200 post-landing and analysed with a 2 (group) × 2 (landing condition) SPM ANOVA (p < 0.05). Results revealed individuals with CAI displayed significantly greater ankle internal rotation post-landing across both landing conditions. Anticipated landings elicited significantly greater pre-landing ankle inversion and external rotation, knee abduction and hip adduction. Additionally, significantly less ankle inversion, knee and hip flexion, and knee adduction and hip abduction were present during post-landing of the anticipated landing. Greater ankle internal rotation during landing may contribute to the ankle 'giving way' in individuals with CAI. However, preparatory and reactive proximal-joint kinematics were similar in both groups during landing. This highlights the possible role of the knee and hip joints in assisting with ankle-joint stability during anticipated inversion perturbations.

Hip biomechanical alterations during walking in chronic ankle instability patients: a cross-correlation analysis.

Chronic ankle instability (CAI) patients often present with centrally-mediated neuromuscular adaptations. Gluteal thickness measures derived from ultrasound imaging (USI) have been correlated to hip biomechanical measures during walking among healthy individuals, however these relationships remain unexplored among CAI patients. The purpose of this study was to compare USI-derived gluteus maximus and medius thickness measures to tri-planar hip kinematics, kinetics, and gluteus medius surface electromyography (sEMG) amplitude during walking among CAI patients. Fifteen females with CAI walked on a treadmill while USI, hip tri-planar kinematics, kinetics, and sEMG were synchronously recorded. Cross-correlation analyses were conducted at 1% intervals (11-ms) from -20% to 20% in the gait cycle. Gluteus medius thickness measures were associated with frontal plane kinematics at a 99-ms lag (cross-correlation coefficient [CCF]: -0.61), transverse plane kinematics at a 66-ms lag (CCF: -0.69), and with hip kinetics at 110-ms lags (CCF: 0.51-0.55). Gluteus medius thickness measures followed sEMG amplitudes by 143-ms (CCF: 0.22). Gluteus maximus thickness was associated with sagittal kinematics at a 220-ms lag (CCF: -0.70), and thickness changes preceded sagittal kinetics at 200-ms (0.87). Compared to reference healthy data, the CAI group presented with differing lag times between USI-derived measures and hip biomechanics, suggesting neuromechanical alterations during walking.

Gluteal Activity During Gait in Patients With Chronic Ankle Instability Following Rehabilitation: A Randomized Controlled Trial.

CONTEXT: Ankle positioning gait biofeedback (GBF) has improved ankle inversion for patients with chronic ankle instability. However, the effects on proximal deficits remain unknown. The purpose of this study was to determine the effects of impairment-based rehabilitation with GBF and without biofeedback on gluteal activity during walking in patients with chronic ankle instability. DESIGN: Randomized controlled trial. METHODS: Eighteen patients with chronic ankle instability (14 women and 4 men; age 22 [4] y; height 171 [10] cm; mass 71.6 [13.8] kg) were recruited from a university setting, following International Ankle Consortium guidelines. Patients were randomly allocated to GBF or without biofeedback groups (N = 9 per group). Both groups performed 4 weeks of exercises and treadmill walking. The GBF group alone received feedback on frontal ankle positioning at initial contact during walking. Ultrasound videos of the gluteus maximus and medius were recorded during walking at baseline and follow-up by a blinded clinician. Gluteal activity ratios were obtained at each 10% of the gait cycle. Statistical parametric mapping repeated-measures analysis of variance were used to compare groups and time points. RESULTS: Both groups demonstrated significantly increased gluteus medius activity across the gait cycle compared with baseline (P < .01, mean differences: 0.13-0.21, Hedge g: 0.97-1.89); however, there were no significant between-group differences. There were no statistically significant changes noted for the gluteus maximus. No adverse events were observed. CONCLUSIONS: Impairment-based rehabilitation led to increased gluteus medius activity, but GBF did not provide any additional improvement to this parameter. Clinicians may consider implementing impairment-based strengthening interventions to improve gluteus medius function during gait for patients with CAI.

Running gait biomechanics in females with chronic ankle instability and ankle sprain copers.

Limited evidence exists comparing running biomechanics between individuals with chronic ankle instability (CAI) and those who fully recover (copers). The purpose of this study was to simultaneously analyse running gait kinematics, kinetics, and surface electromyography (sEMG) between ankle sprain copers and individuals with CAI. Twenty-six (13 CAI, 13 Coper) recreationally active females participated and ran shod on an instrumented treadmill at 2.68 m/s. We assessed lower extremity kinematics and kinetics and sEMG amplitude for the fibularis longus, tibialis anterior, medial gastrocnemius, and gluteus medius muscles. Ten consecutive strides from the beginning of the trial were analysed using statistical parametric mapping (SPM) independent t-test. The CAI group had significantly more ankle inversion during 0-6%, 42-53%, and 96-100% of the running stride cycle compared to the coper group. At initial contact (0%), the CAI group was in an inverted ankle position (5.9°±6.8°) and the coper group was in an everted ankle position (-3.2°±5.5°; p = 0.01, d = 1.5). There were no significant differences identified for any other outcome measures. Increased ankle inversion during the swing phase leading into the loading phase is concerning because the ankle is in an open packed position and inversion is a primary mechanism of injury for sustaining a lateral ankle sprain.

Ultrasound Measures of Intrinsic Foot Muscle Size and Activation Following Lateral Ankle Sprain and Chronic Ankle Instability.

CONTEXT: Tibial nerve impairment and reduced plantarflexion, hallux flexion, and lesser toe flexion strength have been observed in individuals with recent lateral ankle sprain (LAS) and chronic ankle instability (CAI). Diminished plantar intrinsic foot muscles (IFMs) size and contraction are a likely consequence. OBJECTIVES: To assess the effects of ankle injury on IFM size at rest and during contraction in young adults with and without LAS and CAI. SETTING: Laboratory. DESIGN: Cross-sectional. PATIENTS: A total of 22 healthy (13 females; age = 19.6 [0.9], body mass index [BMI] = 22.5 [3.2]), 17 LAS (9 females; age = 21.8 [4.1], BMI = 24.1 [3.7]), 21 Copers (13 females; age = 20.8 [2.9], BMI = 23.7 [2.9]), and 20 CAI (15 females; age = 20.9 [4.7], BMI = 25.1 [4.5]). MAIN OUTCOME MEASURES: Foot Posture Index (FPI), Foot Mobility Magnitude (FMM), and ultrasonographic cross-sectional area of the abductor hallucis, flexor digitorum brevis, quadratus plantae, and flexor hallucis brevis were assessed at rest, and during nonresisted and resisted contraction. RESULTS: Multiple linear regression analyses assessing group, sex, BMI, FPI, and FMM on resting and contracted IFM size found sex (B = 0.45; P < .001), BMI (B = 0.05; P = .01), FPI (B = 0.07; P = .05), and FMM × FPI interaction (B = -0.04; P = .008) accounted for 19% of the variance (P = .002) in resting abductor hallucis measures. Sex (B = 0.42, P < .001) and BMI (B = 0.03, P = .02) explained 24% of resting flexor digitorum brevis measures (P < .001). Having a recent LAS (B = 0.06, P = .03) and FMM (B = 0.04, P = .02) predicted 11% of nonresisted quadratus plantae contraction measures (P = .04), with sex (P < .001) explaining 13% of resting quadratus plantae measures (B = 0.24, P = .02). Both sex (B = 0.35, P = .01) and FMM (B = 0.15, P = .03) predicted 16% of resting flexor hallucis brevis measures (P = .01). There were no other statistically significant findings. CONCLUSIONS: IFM resting ultrasound measures were primarily determined by sex, BMI, and foot phenotype and not injury status. Routine ultrasound imaging of the IFM following LAS and CAI cannot be recommended at this time but may be considered if neuromotor impairment is suspected.

Intra-trunk and arm coordination displayed by Olympic rowing athletes.

The purpose was to assess the intra-trunk and arm coordination of Olympic athletes during rowing on an ergometer. Rowing was performed at three stroke rates (18, 26, and 32 strokes/min). The sagittal plane motions of trunk segments and upper arm were collected for 59 Olympic athletes (32 females and 27 males) from the Chinese National Rowing Team. The coupling angles between the three pairs of segments (lumbar-pelvis, thorax-lumbar, upper arm-thorax) were generated using a vector coding method. The coupling angles were classified: in-phase, anti-phase, superior-phase, and inferior-phase. Three-way, mixed-model ANOVA were used to test the time spent in each coordination pattern. The trunk segments and upper arms demonstrated an in-phase coordination pattern for most of the time. During the drive phase, the time spent in in-phase was increased at higher stroke rates. Athletes are encouraged to use this in-phase pattern, especially between the pelvis and lumbar spine during training with high demands of stroke repetitions or time. During the recovery phase, the trunk segments were rotating mostly in-phase whereas the upper arm was flexing dominantly to maintain stroke length at higher stroke rates. Female and male rowers exhibited similar intra-trunk coordination patterns except for the upper arm-thorax pair.

Age-related gait development in children with autism spectrum disorder.

BACKGROUND: A better understanding of gait development and asymmetries in children with autism spectrum disorder (ASD) may improve the development of treatment programs and thus, patient outcomes. RESEARCH QUESTION: Does age affect walking kinematics and symmetry in children with ASD? METHOD: Twenty-nine children (aged 6-14 years old) with mild ASD (level one) were recruited and assigned to one of the three groups based on their ages: 6-8 years (U8), 9-11 years (U11) and 12-14 years (U14). Walking kinematics were captured using an inertia measurement unit system placed bilaterally on participants' foot, lower leg, upper leg, upper arm, pelvis, and thoracic spine. Joint angles were computed and compared among the age groups. Symmetry angles were used to assess the gait symmetry and were compared among the age groups. RESULTS: Older children exhibited less ankle dorsiflexion and knee flexion angles at heel-strike and greater plantarflexion angles at toe-off compared with younger children. In addition, a decreased pelvis and thorax axial rotation range of motion and increased shoulder flexion/extension range of motion were observed for older children. However, no age-related difference in gait symmetry was observed. SIGNIFICANCE: These findings could suggest that older children with ASD may develop gait kinematics to a more energy-efficient walking pattern.

Running biomechanics as measured by wearable sensors: effects of speed and surface.

Running biomechanics research has traditionally occurred in the laboratory, but with the advent of wearable sensors measurement of running biomechanics may shift outside the laboratory. The purpose was to determine if RunScribe™ wearable sensors could detect differences in kinematic, kinetic and spatiotemporal measures during runs at two speeds and on two different surfaces. Fifteen recreational runners (7 males, 8 females; age = 20.0 ± 3.1 years) participated. While wearing sensors on the heels of their shoes, participants completed four 1600 m runs on both track and grass surfaces. On each surface, the first 1600 m was at a self-selected slow speed followed by the second 1600 m at a self-selected fast pace. The sensors quantified several kinetic, kinematic and spatiotemporal measures. Repeated measures ANOVAs compared the effects of surface and speed. The spatiotemporal measures of stride length, cycle time and contact time were predictably affected by increased running speed and increased surface stiffness, as were the kinematic and kinetic measurements of maximum pronation velocity, maximum pronation excursion, impact g, and braking g (p < 0.050). The RunScribe™ sensors identified expected changes in running biomechanics measures at different speeds and on varying surfaces.

Gait biofeedback and impairment-based rehabilitation for chronic ankle instability.

Our purpose was to analyze the effects of 4 weeks of visual gait biofeedback (GBF) and impairment-based rehabilitation on gait biomechanics and patient-reported outcomes (PROs) in individuals with chronic ankle instability (CAI). Twenty-seven individuals with CAI participated in this randomized controlled trial (14 received no biofeedback (NBF), 13 received GBF). Both groups received 8 sessions of impairment-based rehabilitation. The GBF group received visual biofeedback to reduce ankle frontal plane angle at initial contact (IC) during treadmill walking. The NBF group walked for equal time during rehabilitation but without biofeedback. Dependent variables included three-dimensional kinematics and kinetics at the ankle, knee, and hip, electromyography amplitudes of 4 lower extremity muscles (tibialis anterior, fibularis longus, medial gastrocnemius, and gluteus medius), and PROs (Foot and Ankle Ability Measure Activities of Daily Living (FAAM-ADL), FAAM-Sport, Tampa Scale of Kinesiophobia (TSK), and Global Rating of Change (GROC)). The GBF group significantly decreased ankle inversion at IC (MD:-7.3º, g = 1.6) and throughout the entire stride cycle (peak inversion: MD:-5.9º, g = 1.2). The NBF group did not have significantly altered gait biomechanics. The groups were significantly different after rehabilitation for the FAAM-ADL (GBF: 97.1 ± 2.3%, NBF: 92.0 ± 5.7%), TSK (GBF: 29.7 ± 3.7, NBF: 34.9 ± 5.8), and GROC (GBF: 5.5 ± 1.0, NBF:3.9 ± 2.0) with the GBF group showing greater improvements than the NBF group. There were no significant differences between groups for kinetics or electromyography measures. The GBF group successfully decreased ankle inversion angle and had greater improvements in PROs after intervention compared to the NBF group. Impairment-based rehabilitation combined with visual biofeedback during gait training is recommended for individuals with CAI.

Increased Contact Time and Strength Deficits in Runners With Exercise-Related Lower Leg Pain.

CONTEXT: Exercise-related lower leg pain (ERLLP) is common in runners. OBJECTIVE: To compare biomechanical (kinematic, kinetic, and spatiotemporal) measures obtained from wearable sensors as well as lower extremity alignment, range of motion, and strength during running between runners with and those without ERLLP. DESIGN: Case-control study. SETTING: Field and laboratory. PATIENTS OR OTHER PARTICIPANTS: Of 32 young adults who had been running regularly (>10 mi [16 km] per week) for ≥3 months, 16 had ERLLP for ≥2 weeks and 16 were healthy control participants. MAIN OUTCOME MEASURE(S): Both field and laboratory measures were collected at the initial visit. The laboratory measures consisted of alignment (arch height index, foot posture index, navicular drop, tibial torsion, Q-angle, and hip anteversion), range of motion (great toe, ankle, knee, and hip), and strength. Participants then completed a 1.67-mi (2.69-km) run along a predetermined route to calibrate the RunScribe devices. The RunScribe wearable sensors collected kinematic (pronation excursion and maximum pronation velocity), kinetic (impact g and braking g), and spatiotemporal (stride length, step length, contact time, stride pace, and flight ratio) measures. Participants then wore the sensors during at least 3 training runs in the next week. RESULTS: The ERLLP group had a slower stride pace than the healthy group, which was accounted for as a covariate in subsequent analyses. The ERLLP group had a longer contact time during the stance phase of running (mean difference [MD] = 18.00 ± 8.27 milliseconds) and decreased stride length (MD = -0.11 ± 0.05 m) than the control group. For the clinical measures, the ERLLP group demonstrated increased range of motion for great-toe flexion (MD = 13.9 ± 4.6°) and ankle eversion (MD = 6.3 ± 2.7°) and decreased strength for ankle inversion (MD = -0.49 ± 0.23 N/kg), ankle eversion (MD = -0.57 ± 0.27 N/kg), and hip flexion (MD = -0.99 ± 0.39 N/kg). CONCLUSIONS: The ERLLP group exhibited a longer contact time and decreased stride length during running as well as strength deficits at the ankle and hip. Gait retraining and lower extremity strengthening may be warranted as clinical interventions in runners with ERLLP.

Walking Gait Mechanics and Gaze Fixation in Individuals With Chronic Ankle Instability.

CONTEXT: Many individuals who suffer a lateral ankle sprain will develop chronic ankle instability (CAI). Individuals with CAI demonstrate kinematic differences in walking gait, as well as somatosensory alterations compared with healthy individuals. However, the role of vision during walking gait in this population remains unclear. OBJECTIVE: To evaluate ankle kinematics, gaze deviations, and gaze velocity between participants with CAI and healthy controls while walking on a treadmill during 3 separate visual conditions (no target, fixed target, and moving target). DESIGN: Case-control study. SETTING: Laboratory. Patients (or Other Participants): Ten CAI participants and 10 healthy matched controls participated. MAIN OUTCOME MEASURES: Ankle sagittal and frontal plane kinematics were analyzed for the entire gait cycle. Average and standard deviation (SD) for gaze deviation and gaze velocity were calculated in the horizontal (X) and vertical (Y) planes. RESULTS: No significant differences were found between groups for either ankle kinematics or gaze variables; however, large effect sizes were found in the no target condition for average deviation of X (healthy 0.05 [0.02], CAI 0.12 [0.11]). Moderate effect sizes were identified in the no target condition for SD of Y (healthy 0.04 [0.03], CAI 0.11 [0.15]) and the moving target condition for average velocity of X (healthy 1.56 [0.73], CAI 2.27 [1.15]) and Y (healthy 1.07 [0.51], CAI 1.47 [0.52]). CONCLUSIONS: Although no significant differences were found between groups, it is possible that the role of vision in individuals with CAI may be altered with a more difficult task.

Ankle kinematics, center of pressure progression, and lower extremity muscle activity during a side-cutting task in participants with and without chronic ankle instability.

This study assessed ankle kinematics, surface electromyography, and center-of-pressure (COP) progression relative to the medial border of the foot during a side-cutting task in individuals with and without chronic ankle instability (CAI). Thirty participants (CAI = 15; Controls = 15) performed a side-cutting task on a force platform while 3-dimentional ankle kinematics, COP position, and surface electromyography from the tibialis anterior, medial gastrocnemius, fibularis longus, fibularis brevis, vastus medialis, and semitendinosus were recorded on the testing leg. Ankle kinematics, root-mean-square muscle activity and COP position relative to the medial boarder of the foot were compared between CAI and healthy controls (p < 0.05). Significantly greater ankle internal rotation from 35-54% of the stance phase (p = 0.032) was found for the CAI group compared to controls. Furthermore, significantly greater tibialis anterior muscle activity from 86-94% of the stance phase (p = 0.022) and a more medial COP position from 81-100% (p < 0.05) and of the stance phase was also observed in the CAI group. Less lateral COP progression and increased tibialis anterior activation in the CAI group could reflect a protective movement strategy during anticipated side-cutting to avoid recurrent injury. However, greater ankle internal rotation during mid-stance highlights a potential 'giving way' mechanism in individuals with CAI.

Cross-correlations between gluteal muscle thickness derived from ultrasound imaging and hip biomechanics during walking gait.

Ultrasound imaging (USI) of muscle thickness offers different insights into musculoskeletal function than kinematics, kinetics, and surface electromyography (sEMG), however it is unknown how USI-derived measures correlate to traditional measures during walking. The purpose of this study was to compare USI-derived gluteus maximus (GMAX) and medius (GMED) thickness measures to tri-planar hip kinematics and kinetics, and GMED thickness to sEMG amplitude. Fourteen females walked on a treadmill at 1.34 m/s. GMAX and GMED thickness, hip tri-planar kinematics, kinetics, and GMED sEMG were simultaneously recorded. USI-derived thickness measures were compared to other biomechanical outcomes using cross-correlation analyses, computed at each 1% (11-ms) of the gait cycle with lag times from -20% to 20%. GMED and GMAX thickness measures were most strongly correlated with hip extension and abduction angles at 150-220-ms lags (cross-correlation coefficients [CCF]: -0.34; -0.83). GMED thickness was most correlated to abduction and external rotation moments simultaneously (CCF: -0.28; -0.47). GMAX thickness and flexion moments were most strongly correlated at a 66-ms lag (CCF: 0.33). GMED sEMG amplitude was most strongly correlated to muscle thickness at a 99-ms lag (CCF: 0.39). These results elucidate the unique information provided from USI-derived measures of gluteal muscle thickness during walking.