Adaptive gait responses to varying weight-bearing conditions: Inferences from gait dynamics and H-reflex magnitude.

This study investigates the effects of varying loading conditions on excitability in neural pathways and gait dynamics. We focussed on evaluating the magnitude of the Hoffman reflex (H-reflex), a neurophysiological measure representing the capability to activate motor neurons and the timing and placement of the foot during walking. We hypothesized that weight manipulation would alter H-reflex magnitude, footfall and lower body kinematics. Twenty healthy participants were recruited and subjected to various weight-loading conditions. The H-reflex, evoked by stimulating the tibial nerve, was assessed from the dominant leg during walking. Gait was evaluated under five conditions: body weight, 20% and 40% additional body weight, and 20% and 40% reduced body weight (via a harness). Participants walked barefoot on a treadmill under each condition, and the timing of electrical stimulation was set during the stance phase shortly after the heel strike. Results show that different weight-loading conditions significantly impact the timing and placement of the foot and gait stability. Weight reduction led to a 25% decrease in double limb support time and an 11% narrowing of step width, while weight addition resulted in an increase of 9% in step width compared to body weight condition. Furthermore, swing time variability was higher for both the extreme weight conditions, while the H-reflex reduced to about 45% between the extreme conditions. Finally, the H-reflex showed significant main effects on variability of both stance and swing phases, indicating that muscle-motor excitability might serve as feedback for enhanced regulation of gait dynamics under challenging conditions.

Test-retest reliability and concurrent validity assessment of a novel high-frequency sensor device for anterior tibial translation measurement in loaded and unloaded condition: an exploratory cross-sectional study.

BACKGROUND: Magnetic resonance imaging (MRI) and manual tests remain the standard for diagnosing anterior cruciate ligament (ACL) rupture. Furthermore, the passive knee displacement, also described as anterior tibial translation (ATT), is used in order to make decisions about surgery or to assess rehabilitation outcomes. Unfortunately, these manual tests are limited to passive situations, and their application to assess knee stability in loaded, weight-bearing positions are missing. Therefore, a new device with high-performance sensors and a new sensor setting was developed. The aim of this exploratory cross-sectional study was to assess the test-retest reliability of this new device in a first step and the concurrent validity in a second step. METHODS: A total of 20 healthy volunteers were measured. Measurement consistency of the new device was assessed on the basis of reliability during Lachman test setting and in loaded position by artificial knee perturbation in a test-retest procedure. In a second step, the concurrent validity was evaluated with the Lachmeter® as a reference instrument. Intraclass correlation coefficient (ICC), standard error of measurement (SEM), the minimal detectable change (MDC) and Bland-Altman analysis were evaluated to assess the quality criteria. RESULTS: The measurements with the new device during the Lachman test provided a mean ATT of 5.46±2.22mm. The SEM ranged from 0.60 to 0.69mm resulting in an MDC between 1.67 and 1.93mm for the new device. In the loaded test situation, the mean ATT was 2.11±1.20mm, with test-retest reliability also showing good correlation (r>0.83). The comparison of the two measurement methods with an ICC of (r>0.89) showed good correlation, which also underlines the reasonable agreement of the Bland-Altman analysis. CONCLUSIONS: The evaluation of the test-retest reliability of the new device during the knee stability testing in passive situation as well as in a functional, loaded situation presented good reliability. In addition, the new device demonstrated good agreement with the reference device and therefore good validity. Furthermore, the quality criteria demonstrated the ability of the new device to detect the cut-off value (3-5mm) described in the literature for the diagnosis of ACL-deficient knees, which underlines the clinical relevance of this new device as a reliable and valid tool.

Minimal Out-Toeing and Good Hip Scores of Severe SCFE Patients Treated With Modified Dunn Procedure and Contralateral Prophylactic Pinning at Minimal 5-year Follow up.

BACKGROUND: Slipped capital femoral epiphyses (SCFE) is associated with out-toeing of the foot and external rotation gait. But it is unknown if SCFE patients treated with the modified Dunn procedure have out-toeing at follow up.Therefore, we used instrumented gait analysis and questioned (1) do severe SCFE patients treated with a modified Dunn procedure have symmetrical foot progression angle (FPA) compared with contralateral side and compared with asymptomatic volunteers (2) what is the prevalence of out-toeing gait and what are the outcome socres at follow up. METHODS: Gait analysis of 22 patients (22 hips) treated with an unilateral modified Dunn procedure for severe SCFE (slip angle >60 degrees, 2002 to 2011) was retrospectively evaluated. Of 38 patients with minimal 5-year follow up, 2 hips (4%) had avascular necrosis of the femoral head and were excluded for gait analysis. Twenty-two patients were available for gait analysis at follow up (mean follow up of 9±2 y). Mean age at follow up was 22±3 years. Mean preoperative slip angle was 64±8 degrees (33% unstable slips) and decreased postoperatively (slip angle of 8±4 degrees). Gait analysis was performed with computer-based instrumented walkway system (GAITRite) to measure FPA with embedded pressure sensors. Patients were compared with control group of 18 healthy asymptomatic volunteers (36 feet, mean age 29±6 y). RESULTS: (1) Mean FPA of SCFE patients (3.6±6.4 degrees) at follow up was not significantly different compared with their contralateral side (5.6±5.5 degrees) and compared with FPA of controls (4.0±4.5 degrees). (2) Of the 22 SCFE patients, most of them (19 hips, 86%) had normal FPA (-5 to 15 degrees), 2 patients had in-toeing (FPA<-5 degrees) and 1 had out-toeing (FPA >15 degrees) and was not significantly different compared with control group. (3) Mean modified Harris hip score (mHHS) was 93±11 points, mean Hip Disability and Osteoarthritis Outcome Score (HOOS) score was 91±10 points. Three patients (14%) had mHHS <80 points and walked with normal FPA. The 2 patients with in-toeing and one patient with out-toeing had mHHS >95 points. CONCLUSIONS: Patients with severe SCFE treated with modified Dunn procedure had mostly symmetrical FPA and good hip scores at long term follow up. This is in contrast to previous studies. Although 1 patient had out-toeing and 2 patients had in-toeing at follow up, they had good hip scores. LEVEL OF EVIDENCE: Level III-retrospective comparative study.

Rehabilitation before regenerative cartilage knee surgery: a new prehabilitation guideline based on the best available evidence.

INTRODUCTION: Focal cartilage defects are an increasingly relevant clinical problem especially in athletes. Cartilage regenerative surgery (CRS) including microfracture and autologous chondrocyte implantation (ACI) to treat such isolated cartilage defects in the knee joint has been well established in the last two decades. In contradiction to high-level evidence concerning the surgical technique, cell-related issues, and clinical results, the knowledge about the optimal rehabilitation process is still sparse although the importance of optimizing the rehabilitation process has recently led to new research focus in this field. The preoperative time frame may be used to start rehabilitation which may fasten the postoperative recovery and optimize clinical outcome ("Prehabilitation"-PREHAB). The aim of this article, therefore, was to review the available literature on prehabilitation concepts and to present a prehabilitation guideline for CRS patients based on the best evidence available. METHODS: A systemic literature research was conducted on rehabilitation for cartilage regenerative surgery as well as prehabilitation in knee joint procedures. From the available literature a prehabilitation concept was generated and tested in 10 ACI patients. RESULTS: As the literature search found no studies addressing prehabilitation in CRS patients, an evidence-based PREHAB program has been compiled based on the available evidence from (a) studies addressing postoperative rehabilitation in CRS patients and (b) PREHAB studies on other knee procedures including TKA. This presented prehabilitation guideline has been tested in > 50 CRS patients and was found to be feasible as all of the patients showed a good compliance and were able to perform the protocol as suggested. CONCLUSION: The presented PREHAB regimen may serve clinicians as a guideline for early rehabilitation of their CRS patients. Obviously, further research is mandatory to quantify its clinical effect and to demonstrate its cost-effectiveness and benefits in surgically treated patients.

Sensorimotor Exercises and Enhanced Trunk Function: A Randomized Controlled Trial.

The aim of this study was to investigate the effect of a 6-week sensorimotor or resistance training on maximum trunk strength and response to sudden, high-intensity loading in athletes.Forty-three healthy, well-trained participants were randomized into sensorimotor (SMT; n=11), resistance training (RT; n=16) and control groups (CG; n=16). Treatment groups received either sensorimotor training (SMT) or resistance training (RT) for 6 weeks, 3 times a week. At baseline and after 6 weeks of intervention, participants' maximum isokinetic strength in trunk rotation and extension was tested (concentric/eccentric 30°/s). In addition, sudden, high-intensity trunk loading was assessed for eccentric extension and rotation, with additional perturbation. Peak torque [Nm] was calculated as the outcome.Interventions showed no significant difference for maximum strength in concentric and eccentric testing (p>0.05). For perturbation compensation, higher peak torque response following SMT (Extension: +24 Nm 95%CI±19 Nm; Rotation: +19 Nm 95%CI±13 Nm) and RT (Extension: +35 Nm 95%CI±16 Nm; Rotation: +5 Nm 95%CI±4 Nm) compared to CG (Extension: -4 Nm 95%CI±16 Nm; Rotation: -2 Nm 95%CI±4 Nm) was present (p<0.05).This study showed that isokinetic strength gains were small, but that significant improvements in high-intensity trunk loading response could be shown for both interventions. Therefore, depending on the individual's preference, therapists have two treatment options to enhance trunk function for back pain prevention.

Quantitative work demands, emotional demands, and cognitive stress symptoms in surgery nurses.

In surgery, cognitive stress symptoms, including problems in concentrating, deciding, memorising, and reflecting are risks to patient safety. Recent evidence points to social stressors as antecedents of cognitive stress symptoms in surgery personnel. The current study tests whether cognitive stress symptoms are positively associated with emotional abuse, emotional- and task-related demands and resources in surgery work. Forty-eight surgery nurses from two hospitals filled out the Copenhagen Psychosocial Questionnaire in its German version. Task-related and emotional demands were positively related to cognitive stress symptoms. In a stepwise, multiple, linear regression of cognitive stress symptoms on task-related and emotional demands, emotional abuse and emotional demands were unique predictors (p < .05). Efforts to increase patient safety should address emotional abuse, emotional demands, and, therefore, communication and cooperation team climate in surgery personnel.

Influence of Load on Three-Dimensional Segmental Trunk Kinematics in One-Handed Lifting: A Pilot Study.

Stability of the trunk is relevant in determining trunk response to different loading in everyday tasks initiated by the limbs. Descriptions of the trunk's mechanical movement patterns in response to different loads while lifting objects are still under debate. Hence, the aim of this study was to analyze the influence of weight on 3-dimensional segmental motion of the trunk during 1-handed lifting. Ten asymptomatic subjects were included (29 ± 3 y; 1.79 ± 0.09 m; 75 ± 14 kg). Subjects lifted 3× a light and heavy load from the ground up onto a table. Three-dimensional segmental trunk motion was measured (12 markers; 3 segments: upper thoracic area [UTA], lower thoracic area [LTA], lumbar area [LA]). Outcomes were total motion amplitudes (ROM;[°]) for anterior flexion, lateral flexion, and rotation of each segment. The highest ROM was observed in the LTA segment (anterior flexion), and the smallest ROM in the UTA segment (lateral flexion). ROM differed for all planes between the 3 segments for both tasks (P < .001). There were no differences in ROM between light and heavy loads (P > .05). No interaction effects (load × segment) were observed, as ROM did not reveal differences between loading tasks. Regardless of weight, the 3 segments did reflect differences, supporting the relevance of multisegmental analysis.

Low-Budget Instrumentation of a Conventional Leg Press to Measure Reliable Isometric-Strength Capacity.

Maximum strength and rate of force development (RFD) are 2 important strength characteristics for everyday tasks and athletic performance. Measurements of both parameters must be reliable. Expensive isokinetic devices with isometric modes are often used. The possibility of cost-effective measurements in a practical setting would facilitate quality control. The purpose of this study was to assess the reliability of measurements of maximum isometric strength (Fmax) and RFD on a conventional leg press. Sixteen subjects (23 ± 2 y, 1.68 ± 0.05 m, 59 ± 5 kg) were tested twice within 1 session. After warm-up, subjects performed 2 times 5 trials eliciting maximum voluntary isometric contractions on an instrumented leg press (1- and 2-legged randomized). Fmax (N) and RFD (N/s) were extracted from force-time curves. Reliability was determined for Fmax and RFD by calculating the intraclass correlation coefficient (ICC), the test-retest variability (TRV), and the bias and limits of agreement. Reliability measures revealed good to excellent ICCs of .80-.93. TRV showed mean differences between measurement sessions of 0.4-6.9%. The systematic error was low compared with the absolute mean values (Fmax 5-6%, RFD 1-4%). The implementation of a force transducer into a conventional leg press provides a viable procedure to assess Fmax and RFD. Both performance parameters can be assessed with good to excellent reliability allowing quality control of interventions.

Trunk extensor and flexor strength capacity in healthy young elite athletes aged 11-15 years.

Differences in trunk strength capacity because of gender and sports are well documented in adults. In contrast, data concerning young athletes are sparse. The purpose of this study was to assess the maximum trunk strength of adolescent athletes and to investigate differences between genders and age groups. A total of 520 young athletes were recruited. Finally, 377 (n = 233/144 M/F; 13 ± 1 years; 1.62 ± 0.11 m height; 51 ± 12 kg mass; training: 4.5 ± 2.6 years; training sessions/week: 4.3 ± 3.0; various sports) young athletes were included in the final data analysis. Furthermore, 5 age groups were differentiated (age groups: 11, 12, 13, 14, and 15 years; n = 90, 150, 42, 43, and 52, respectively). Maximum strength of trunk flexors (Flex) and extensors (Ext) was assessed in all subjects during isokinetic concentric measurements (60°·s(-1); 5 repetitions; range of motion: 55°). Maximum strength was characterized by absolute peak torque (Flexabs, Extabs; N·m), peak torque normalized to body weight (Flexnorm, Extnorm; N·m·kg(-1) BW), and Flexabs/Extabs ratio (RKquot). Descriptive data analysis (mean ± SD) was completed, followed by analysis of variance (α = 0.05; post hoc test [Tukey-Kramer]). Mean maximum strength for all athletes was 97 ± 34 N·m in Flexabs and 140 ± 50 N·m in Extabs (Flexnorm = 1.9 ± 0.3 N·m·kg(-1) BW, Extnorm = 2.8 ± 0.6 N·m·kg(-1) BW). Males showed statistically significant higher absolute and normalized values compared with females (p < 0.001). Flexabs and Extabs rose with increasing age almost 2-fold for males and females (Flexabs, Extabs: p < 0.001). Flexnorm and Extnorm increased with age for males (p < 0.001), however, not for females (Flexnorm: p = 0.26; Extnorm: p = 0.20). RKquot (mean ± SD: 0.71 ± 0.16) did not reveal any differences regarding age (p = 0.87) or gender (p = 0.43). In adolescent athletes, maximum trunk strength must be discussed in a gender- and age-specific context. The Flexabs/Extabs ratio revealed extensor dominance, which seems to be independent of age and gender. The values assessed may serve as a basis to evaluate and discuss trunk strength in athletes.

Bilateral neuromuscular control in patients one year after unilateral ACL rupture or reconstruction. A cross-sectional study.

Objectives: To compare bilateral neuromuscular control in patients one year after anterior cruciate ligament reconstruction (ACL-R) or conservative treatment (ACL-C) to healthy controls (ACL-I). Design: Cross-sectional study. Setting: Electromyography of vastus medialis (VM) and lateralis (VL), biceps femoris (BF) and semitendinosus (ST) was recorded during stair descent and anterior tibial translation. Each step of stair descent was divided into pre-activity, weight-acceptance and push-off phase. Pre-activation, short, medium (MLR) and long latency responses (LLR) were defined for reflex activity. Participants: N = 38 patients one year after ACL reconstruction (ACL-R), N = 26 participants with conservative treatment one year after ACL rupture (ACL-C), N = 38 healthy controls with an intact ACL (ACL-I). Main outcome measures: Normalized root mean squares per muscle and phase (α = 0.05). Results: During stair descent, within-group leg differences were found for the quadriceps in ACL-R during all phases and for the BF in ACL-C during weight-acceptance. Between-group leg differences were found for BF in both patient groups compared to ACL-I during push-off.Between-group differences in pre-activation for VM between ACL-R and ACL-C, and between ACL-C and ACL-I were found, and as LLR between patients and ACL-R versus ACL-I. Pre-activation of BF and MLR of ST differed for each patient group compared to ACL-I. Conclusions: Bilateral neuromuscular alterations are still present one year after ACL rupture or reconstruction.

Evaluation of hop test movement quality to enhance return to sport testing. A cross-sectional study.

Introduction: Return to Sport tests with functional hop tests are often used to decide when a person is ready to return to sport after an anterior cruciate ligament (ACL) injury. Poor movement quality, such as knee valgus, hip adduction and hip internal rotation is considered a risk factor for ACL injury. However, it is unclear whether existing tests adequately cover the aspect of movement quality. This study aims to investigate whether there is a relationship between the calculated limb symmetry index (LSI) of hop tests as an indication of performance and the total score of the "Quality First" assessment (movement quality). The second aim is to examine the reliability of the newly developed "Quality First" assessment for evaluating movement quality in hop tests. Methods: The cross-sectional study recruited 34 patients with an ACL reconstruction. The vertical hop, single-leg hop for distance, and side hop tests were performed and recorded. The video recordings were assessed using the "Quality First" assessment. The Spearman correlation coefficient was calculated using the LSI and the "Quality First" total score. Intraclass correlation coefficients (ICC) and standard error of measurements (SEM) were used to calculate intra- and interrater reliability. In addition, the minimal detectable change (MDC) was determined. Results: The correlation test between the LSI and the "Quality First" total score showed no correlation for all three jumps (r = -0.1-0.02/p-value = 0.65-0.93). The interrater reliability of the "Quality First" assessment showed fair to good reliability (ICC2: 0.45-0.60), with SEM ranging from 1.46 to 1.73 and the MDC from 4.06 to 4.8. Intrarater reliability was good to excellent (ICC3: 0.73-0.85), with SEM values ranging from 0.89 to 1.09 and the MDC from 2.47 to 3.01. Conclusion: The quality of movement, measured with the "Quality First" assessment, indicated no correlation with the calculated LSI from jump performance, therefore movement quality should also be examined in Return to Sport tests. The "Quality First" assessment shows fair to good reliability when used by different raters. When used multiple times by the same rater, the assessment has good to excellent reliability.

Sex-specific differences in neuromuscular activation of the knee stabilizing muscles in adults - a systematic review.

INTRODUCTION: The rupture of the anterior cruciate ligament (ACL) is one of the most common injuries of the knee. Women have a higher injury rate for ACL ruptures than men. Various indicators for this sex-specific difference are controversially discussed. AIM: A systematic review of the literature that compares surface electromyography (EMG) values of adult female and male subjects to find out if there is a difference in neuromuscular activation of the knee stabilizing muscles. METHODS: This systematic review has been guided and informed by the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Studies which examined sex-specific differences with surface EMG measurements (integral, root mean squares, mean values, analysis of time and amplitude) of the knee stabilizing muscles were retrieved via searches from the databases PubMed, CINAHL, Embase, CENTRAL and SPORTDiscus. The risk of bias of included studies was assessed with the National Heart, Lung and Blood Institute (NHLBI) study quality assessment tool. A synthesis of results was performed for relevant outcomes. RESULTS: Fifteen studies with 462 healthy participants, 233 women (mean age 21.9 (± 2.29) years) and 299 men (mean age 22.6 (± 2.43) years), were included in the systematic review. The methodological quality of the studies was mostly rated "fair" (40%). A significantly higher activity of the muscles vastus lateralis and vastus medialis was found in females, in three studies. Two studies found significantly lower neuromuscular activity in the muscles biceps femoris and semitendinosus in females. All other included studies found no significant differences or reported even contradicting results. CONCLUSION: The controversial findings do not allow for a concluding answer to the question of a sex-specific neuromuscular activation. Further research with higher statistical power and a more homogeneous methodical procedure (tasks and data normalisation) of the included studies may provide insight into possibly existing sex-specific differences in neuromuscular activation. This systematic review could help to improve the methodical design of future studies to get a more valid conclusion of the issue. TRIAL REGISTRATION: CRD42020189504.

Reliability of the active knee joint position sense test and influence of limb dominance and sex.

The output of a sensorimotor performance can be measured with the joint position sense (JPS) test. However, investigations of leg dominance, sex and quality measures on this test are limited. Therefore, these potential influencing factors as well as reliability and consistency measures were evaluated for angular reproduction performance and neuromuscular activity during the active knee JPS test in healthy participants. Twenty healthy participants (10 males; 10 females; age 29 ± 8 years; height 165 ± 39 cm; body mass 69 ± 13 kg) performed a seated knee JPS test with a target angle of 50°. Measurements were conducted in two sessions separated by two weeks and consisted of two blocks of continuous angular reproduction (three minutes each block). The difference between reproduced and target angle was identified as angular error measured by an electrogoniometer. During reproduction, the neuromuscular activity of the quadriceps muscle was assessed by surface electromyography. Neuromuscular activity was normalized to submaximal voluntary contraction (subMVC) and displayed per muscle and movement phase. Differences between leg dominance and sex were calculated using Friedman-test (α = 0.05). Reliability measures including intraclass correlation coefficient (ICC), Bland-Altman analysis (bias ± limits of agreement (LoA)) and minimal detectable change (MDC) were analysed. No significant differences between leg dominance and sex were found in angular error and neuromuscular activity. Angular error demonstrated inter-session ICC scores of 0.424 with a bias of 2.4° (± 2.4° LoA) as well as MDC of 6.8° and moderate intra-session ICC (0.723) with a bias of 1.4° (± 1.65° LoA) as well as MDC of 4.7°. Neuromuscular activity for all muscles and movement phases illustrated inter-session ICC ranging from 0.432 to 0.809 with biases between - 2.5 and 13.6% subMVC and MDC from 13.4 to 63.9% subMVC. Intra-session ICC ranged from 0.705 to 0.987 with biases of - 7.7 to 2.4% subMVC and MDC of 2.7 to 46.5% subMVC. Leg dominance and sex seem not to influence angular reproduction performance and neuromuscular activity. Poor to excellent relative reliability paired with an acceptable consistency confirm findings of previous studies. Comparisons to pathological populations should be conducted with caution.

[Manual spinal therapy techniques to stimulate the autonomic nervous system: a scoping review]. / Manuelle Therapietechniken an der Wirbelsäule zur Stimulation des autonomen Nervensystems - ein Scoping Review.

BACKGROUND: Physical interventions or manual therapeutic techniques (MTTe) such as mobilisation, manipulation or soft tissue techniques not only have an influence on the target tissue with improvement of metabolism or reduction of hypertonic muscles. They are also used for balance regulation in central nervous changes of the autonomic nervous system (ANS). To date, there is a lack of empirical evidence on impact mechanisms and target locations of MTTe on the ANS. This scoping review aims to provide an overview of the evidence on the application of MTTe at diverse levels of the spine with a view to the ANS. METHOD: A systematic literature search was conducted on CENTRAL, Google Scholar, Osteopathic Research Web, PEDro and PubMed. The scope and content of the literature were documented. The results of the included and referenced studies were summarised in a narrative approach with the focus being on the most significant clinical aspects. RESULTS: MTTe was described as manipulations, mobilisations, myofascial techniques and cervical traction. In 27 out of 35 studies, therapeutic treatments were carried out on healthy volunteers. Ten studies analysed immediate effects in patients, while two studies were designed as longitudinal studies in patients with hypertension. Over a period of four to eight weeks, the frequency of intervention was between one and three MTTe sessions a week. CONCLUSION: The study results proved to be heterogeneous. For this reason, it is not possible to draw definitive, explicit and generally valid statements regarding the type and intensity as well as the segmental level at which MTTe should be applied in order to trigger specific positive ANS response mechanisms. Consequently, longitudinal studies with follow-up are recommended for future studies. In addition, comprehensive effects of MTTe should be evaluated in groups of patients with different characteristics.

Neuromuscular control in males and females 1 year after an anterior cruciate ligament rupture or reconstruction during stair descent and artificial tibial translation.

Neuromuscular alterations are reported in patients with anterior cruciate ligament reconstruction (ACL-R) and conservative treatment (copers with ACL deficiency, ACL-C). However, it is unclear whether sex influences neuromuscular control. The objective was to investigate differences in neuromuscular control regarding sex and treatment type one year after ACL rupture in comparison to a group with an intact ACL (ACL-I). Electromyography of vastus medialis (VM) and lateralis, biceps femoris (BF) and semitendinosus (ST) was recorded in ACL-R (N = 38), ACL-C (N = 26), and ACL-I (N = 38) during stair descent and reflex activity by anterior tibial translation while standing. The movements of stair descent were divided into pre-activity, weight-acceptance and push-off phases, reflex activity in pre-activation, short, medium (MLR), and long latency responses (LLR). Normalized root mean squares for each muscle of involved and matched control limb per phase were calculated and analyzed with two-way ANOVA (α = 0.05). During stair descent, neuromuscular differences of BF were significant during push-off only (p = 0.001). Males of ACL-R and ACL-C had higher BF activity compared to ACL-I (p = 0.009, 0.007 respectively). During reflex activity, VM and BF were significantly different between treatment groups for pre-activation (p = 0.013, 0.035 respectively). VM pre-activation of females was higher in ACL-R compared to ACL-C (p = 0.018), and lower in ACL-C compared to ACL-I (p = 0.034). Males of ACL-R showed higher VM and less BF pre-activation (p = 0.025, p = 0.003 respectively) compared to ACL-I. Males of ACL-C had less BF pre-activation compared to ACL-I (p = 0.019). During MLR, intra-group differences in ST were found for treatment (p = 0.011) and females of ACL-R compared to ACL-I (p = 0.015). During LLR, overall intra-group differences in VM were present for treatment (p = 0.034) and in females (ACL-R versus ACL-C (p = 0.015), ACL-I (p = 0.049), respectively). One year after an ACL rupture, neuromuscular alterations persist regardless of treatment and sex. Standard rehabilitation protocols may not be able to restore neuromuscular control. Future research should include long-term follow up and focus on exercises targeting neuromuscular function.

Determining key clinical predictors for chronic ankle instability and return to sports with cost of illness analysis: protocol of a prospective cohort study.

INTRODUCTION: Ankle sprains are common in sports and the general population. Although considered innocuous, a large proportion has residual complaints such as recurrent ankle sprains and develop chronic ankle instability. Although some predicting factors are identified, there is no unequivocality regarding the development of chronic ankle instability, nor about the optimal rehabilitation for an acute ankle sprain. Alongside the biomechanical impairments, ankle sprains are a burden on society due to substantial economic costs. Therefore, we aim to identify key clinical predictors of chronic ankle instability or recovery after acute lateral ankle sprain. Additionally, we aim to determine cost-of-illness of patients who developed chronic ankle instability. METHODS AND ANALYSIS: This prospective cohort study (Clinicaltrials.gov: NCT05637008 - pre-results) aims to recruit adult (18-55 years) patients with an acute lateral ankle sprain who are active in sports. Clinical assessments and patient-reported outcome measures will be used to collect data at 7-14 days, 6 weeks, 12 weeks and 12 months after enrolment in the study. The primary outcome will be chronic ankle instability at 12-month follow-up. Salient outcomes will be analysed by logistic regression to determine association with the development of chronic ankle instability. Participants will fill in a cost diary containing direct and indirect costs related to their injury. ETHICS AND DISSEMINATIONS: The ethical committee of the Antwerp University Hospital (B3002022000138) has given approval of the protocol and consent forms on 10 October 2022. We perform this study according to the Helsinki Declaration. We will present results at conferences or webinars and publish in peer-reviewed articles.NCT05637008.

[Return to Sport (RTS) After Anterior Cruciate Ligament Reconstruction: Which Factors Influence the RTS Decision?] / Rückkehr zum Sport nach Rekonstruktion des vorderen Kreuzbandes ­ Welche Faktoren beeinflussen die Return to Sport-Entscheidung?

BACKGROUND: It is unknown which valid criteria should be considered to justify the decision for return to sport (RTS) following anterior cruciate ligament reconstruction (ACLR). The research question is whether gender, age, the outcome of the isokinetic maximal strength measurement and the single-leg hop test (quantitative/qualitative) influence the decision for RTS nine months after ACLR. METHODS: This study is a retrospective data analysis. The research question was evaluated with a multiple logistic regression analysis (MLR). The dependent variable, RTS yes/no, is based on the decision of the orthopaedist in charge of treatment nine months (±30 days) after ACLR. The following possible influencing factors were investigated: gender, age, limb symmetry index (LSI) of maximal knee extension and knee flexion strength at 60°/sec., LSI of single-leg hop test and evaluation of knee valgus. RESULTS: Data of 71 patients were included for MLR. The odds ratios (OR) for RTS increased with female gender (OR, 4.808; p=0.035), a higher LSI of maximal strength of knee extension (OR, 1.117; p=0.009) and a higher LSI of the single-leg hop test (OR, 1.125; p=0.020). Age, the LSI of maximal strength of knee flexion and knee valgus had no influence on the RTS decision. CONCLUSION: Gender and the limb symmetry indexes of the maximal strength of knee extension and of the single-leg hop test are associated with RTS nine months after ACLR. These results should be considered to optimise rehabilitation after ACLR.

Content validity, interpretability, and internal consistency of the "Quality First" assessment to evaluate movement quality in hop tests following ACL rehabilitation. A cross-sectional study.

Introduction: Current approaches fail to adequately identify sport readiness after anterior cruciate ligament (ACL) rehabilitation. Altered landing biomechanics after ACL reconstruction are associated with increased risk of a noncontact ACL reinjury. There is a lack of objective factors to screen for deficient movement patterns. Therefore, the aim of this study was to investigate content validity, interpretability, and internal consistency for the newly developed "Quality First" assessment to evaluate movement quality during hop tests in patients after ACL rehabilitation. Method: Participants in this cross-sectional study were recruited in collaboration with the Altius Swiss Sportmed Center in Rheinfelden, Switzerland. After a successful ACL reconstruction, the movement quality of 50 hop test batteries was evaluated between 6 and 24 months postoperatively with the "Quality First" assessment. Content validity was assessed from the perspective of professionals. To check the interpretability, classical test theory was employed. Cronbach's α was calculated to evaluate internal consistency. Results: Content validity resulted in the inclusion of three different hop tests (single-leg hop for distance, vertical hop, and side hop). The "Quality First" assessment is enabled to evaluate movement quality in the sagittal, vertical, and the transversal plane. After the exclusion process, the "Quality First" assessment was free from floor and ceiling effects and obtained a sufficient Cronbach's α. The final version consists of 15 items, rated on a 4-point scale. Discussion: By means of further validations, the "Quality First" assessment could offer a possibility to evaluate movement quality after ACL rehabilitation during hop tests.

Rehabilitation strategies for lateral ankle sprain do not reflect established mechanisms of re-injury: A systematic review.

OBJECTIVES: 1) determine the primary impairment addressed by each exercise included in exercise-based rehabilitation programs for patients with an acute ankle sprain; 2) Determine whether prescribed exercises incorporate complex tasks associated with ankle sprain injury mechanisms? METHODS: We searched databases CINAHL, Web of Science, SPORTDiscus, Cochrane Register of Controlled Trials, PEDro, Google Scholar for RCT's including patients with acute ankle sprains, managed through exercise-based rehabilitation. Risk of bias was assessed by the Risk of Bias 2 tool. Exercises were analysed based on: the primary impairment(s) addressed; direction of movement; base of support; weightbearing status; flight phase. (PROSPERO: CRD42020210858) RESULTS: We included fourteen RCT's comprising 177 exercises. Neuromuscular function was addressed in 44% of exercises, followed by performance tasks (23%), and muscle strengthening (20%). Exercises were limited to movements across the sagittal plane (48%), with 31% incorporating multiplanar movements. Weight bearing exercises were almost divided equally between single-limb (59/122) and double leg stance exercises (61/122). Eighteen percent of all exercises incorporated a flight phase. CONCLUSIONS: Rehabilitation after LAS comprises simple exercises in the sagittal plane that do not reflect mechanisms of re-injury. Future interventions should incorporate more open chain joint position sense training, multiplanar single limb challenges, and jumping and landing exercises.

Assessing lower extremity loading during activities of daily living using continuous-scale physical functional performance 10 and wireless sensor insoles: a comparative study between younger and older adults.

PURPOSE: This study aims to investigate the lower extremity loading during activities of daily living (ADLs) using the Continuous Scale of Physical Functional Performance (CS-PFP 10) test and wireless sensor insoles in healthy volunteers. METHODS: In this study, 42 participants were recruited, consisting of 21 healthy older adults (mean age 69.6 ± 4.6 years) and 21 younger healthy adults (mean age 23.6 ± 1.8 years). The performance of the subjects during ADLs was assessed using the CS-PFP 10 test, which comprised 10 tasks. The lower extremity loading was measured using wireless sensor insoles (OpenGo, Moticon, Munich, Germany) during the CS-PFP 10 test, which enabled the measurement of ground reaction forces, including the mean and maximum total forces during the stance phase, expressed in units of body weight (BW). RESULTS: The total CS-PFP 10 score was significantly lower in older participants compared to the younger group (mean total score of 57.1 ± 9.0 compared to 78.2 ± 5.4, respectively). No significant differences in the mean total forces were found between older and young participants. The highest maximum total forces were observed during the tasks 'endurance walk' (young: 1.97 ± 0.34 BW, old: 1.70 ± 0.43 BW) and 'climbing stairs' (young: 1.65 ± 0.36 BW, old: 1.52 ± 0.28 BW). Only in the endurance walk, older participants showed a significantly higher maximum total force (p < 0.001). CONCLUSION: The use of wireless sensor insoles in a laboratory setting can effectively measure the load on the lower extremities during ADLs. These findings could offer valuable insights for developing tailored recommendations for patients with partial weight-bearing restrictions.