De novo variants in FRMD5 are associated with developmental delay, intellectual disability, ataxia, and abnormalities of eye movement.

Proteins containing the FERM (four-point-one, ezrin, radixin, and moesin) domain link the plasma membrane with cytoskeletal structures at specific cellular locations and have been implicated in the localization of cell-membrane-associated proteins and/or phosphoinositides. FERM domain-containing protein 5 (FRMD5) localizes at cell adherens junctions and stabilizes cell-cell contacts. To date, variants in FRMD5 have not been associated with a Mendelian disease in OMIM. Here, we describe eight probands with rare heterozygous missense variants in FRMD5 who present with developmental delay, intellectual disability, ataxia, seizures, and abnormalities of eye movement. The variants are de novo in all for whom parental testing was available (six out of eight probands), and human genetic datasets suggest that FRMD5 is intolerant to loss of function (LoF). We found that the fly ortholog of FRMD5, CG5022 (dFrmd), is expressed in the larval and adult central nervous systems where it is present in neurons but not in glia. dFrmd LoF mutant flies are viable but are extremely sensitive to heat shock, which induces severe seizures. The mutants also exhibit defective responses to light. The human FRMD5 reference (Ref) cDNA rescues the fly dFrmd LoF phenotypes. In contrast, all the FRMD5 variants tested in this study (c.340T>C, c.1051A>G, c.1053C>G, c.1054T>C, c.1045A>C, and c.1637A>G) behave as partial LoF variants. In addition, our results indicate that two variants that were tested have dominant-negative effects. In summary, the evidence supports that the observed variants in FRMD5 cause neurological symptoms in humans.

Growth patterns in individuals with CDKL5 deficiency disorder.

AIM: To compare growth in individuals with cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder with population norms and to investigate the effect of gastrostomy on growth. METHOD: The longitudinal study included 353 individuals from the International CDKL5 Disorder Database with any anthropometric measurement in baseline and/or follow-up questionnaires. The British 1990 growth reference was used to determine the age- and sex-standardized z-score. Repeated cross-sectional data were fitted using a Gaussian linear regression model with generalized estimating equations. RESULTS: All growth parameters were below the general population norm (mean z-scores: weight -0.97, height -0.65, body mass index [BMI] -0.81, head circumference -2.12). The disparity was particularly pronounced for all anthropometric measurements after 4 years of age except for BMI. Moreover, individuals with gastrostomy placement were shown to have a larger decrease than those without. INTERPRETATION: In addition to weight, height, and BMI, head circumference was also compromised in this disorder. Microcephaly could be considered a helpful diagnostic feature, especially in adults. Any benefit of gastrostomy on weight and BMI was mainly seen in the early years.

Limb Dominance Effects on Seated Single-Arm Shot-Put Limb Symmetry Indices Following Shoulder Rehabilitation.

CONTEXT: Typically, most clinical return to activity guidelines recommend that an injured shoulder achieve a 90% to 100% functional performance test limb symmetry index (LSI); however, as previous research demonstrated a 103% to 111% dominant limb bias in seated single-arm shot-put test (SSASPT) performance, the typical criteria might not be appropriate for interpreting SSASPT LSI. Thus, the current objective was to evaluate SSASP LSI differences between dominant and nondominant involved shoulders and to determine how many patients met the suggested 90% to 100% LSI criteria, as well as the 103% for dominant (89% for nondominant) normative SSASPT threshold reported in the literature, at the time of discharge. DESIGN: Cross-sectional. METHODS: Patients with shoulder injury or surgery (n = 78) completed the SSASPT at the time of discharge from rehabilitation and were grouped according to whether the involved shoulder was the dominant (n = 42) or nondominant (n = 32) limb. LSI (involved/uninvolved × 100) was computed from the average of 3 SSASPT trial distances completed with each limb. RESULTS: The LSI for the nondominant involved group (88.9% [12.4%]) was significantly less (confidence intervalDiff, -12.1% to -22.1%) than the dominant involved group (106.0% [9.3%]). While 95.2% of patients in the dominant involved group exhibited LSI > 90%, only 43.8% of patients in the nondominant involved group attained LSI > 90%. Across the entire cohort, the odds of a nondominant involved LSI being below the respective SSASPT normative range were 2.04 (95% confidence interval, 0.80-5.21) times higher than the odds of a dominant involved LSI being below the normative range. CONCLUSIONS: Patients with dominant limb involvement exhibited higher LSI than patients with nondominant limb involvement at discharge from rehabilitation. Particularly when the nondominant shoulder is involved, these results suggest that patients with shoulder injury and surgery may require longer rehabilitation to attain higher levels of upper-extremity function.

Association Between the Seated Single-Arm Shot-Put Test With Isokinetic Pushing Force.

CONTEXT: Previous investigations have examined the reliability, normalization, and underlying projection mechanics of the seated single-arm shot-put (SSASP) test. Although the test is believed to reflect test limb strength, there have been no assessments determining whether test performance is directly associated with upper-extremity strength. OBJECTIVE: To determine the relationship between isokinetic pushing force and SSASP performance and conduct a method comparison analysis of limb symmetry indices between the 2 tests. DESIGN: Controlled laboratory study. SETTING: Biomechanics laboratory. Patients (or Other Participants): Twenty-four healthy and physically active men (n = 12) and women (n = 12). INTERVENTION(S): Participants completed the SSASP and isokinetic pushing tests using their dominant and nondominant arms. MAIN OUTCOME MEASURES: SSASP distance and isokinetic peak force. RESULTS: Significant moderate to strong relationships were revealed between the SSASP distances and isokinetic peak forces for both limbs. The Bland-Altman analysis results demonstrated significantly (P < .002) greater limb symmetry indices for the SSASP (both medicine balls) than the isokinetic ratios, with biases ranging from -0.094 to -0.159. The limits of agreement results yielded intervals ranging from ±0.241 to ±0.340 and ±0.202 to ±0.221 from the biases. CONCLUSIONS: These results support the notion that the SSASP test reflects upper-extremity strength. The incongruency of the limb symmetry indices between the 2 tests is likely reflective of the differences in the movement patterns and coordination requirements of the 2 tests.

Relationship Between Seated Single-Arm Shot Put and Isokinetic Shoulder Flexion and Elbow Extension Strength.

CONTEXT: A recent report demonstrated moderate to strong relationships between seated single-arm shot-put (SSASP) test performance and isokinetic pushing forces at varying velocities, directly supporting the SSASP test as a reflection of multijoint upper-extremity strength. Yet, no previous work appears to have assessed whether the SSASP test is more reflective of shoulder flexion or elbow extension strength. OBJECTIVE: To examine the relationship between isokinetic shoulder flexion and elbow extension strength and SSASP test performance and to compare limb symmetry indices (LSI) between the 2 tests. DESIGN: Correlational design. SETTING: Biomechanics laboratory. Patients (or Other Participants): A total of 30 healthy and physically active young adults. INTERVENTION(S): Participants completed the SSASP test and concentric isokinetic (60°/s and 180°/s) shoulder flexion and elbow extension using their dominant and nondominant arms. MAIN OUTCOME MEASURES: SSASP test performance and isokinetic shoulder flexion and elbow extension peak torques as well as LSI between the 2 tests. RESULTS: Strong relationships were observed between SSASP ranges and isokinetic peak torques at each velocity for both shoulder and elbow (r ≥ .804, P < .001). While the Bland-Altman results on the LSI only demonstrated a significant bias for the shoulder (60°/s, P = .009), limits of agreement results demonstrated extremely wide intervals (32.5%-52.1%). CONCLUSIONS: The SSASP test is a multijoint upper-extremity functional performance test that is reflective of equal shoulder flexion and elbow extension contributions; however, there was large variability regarding the agreement between the SSASP LSI and isokinetic shoulder and elbow strength LSI.

Effects of Trial Duration on Intrasession Reliability of Single Leg Balance Testing on Stable and Unstable Surfaces.

CONTEXT: Single leg balance testing is a commonly used tool in sports medicine; however, there has been no consensus on trial duration needed to obtain reliable measures. OBJECTIVE: This investigation sought to determine the minimum trial duration required to obtain the highest intrasession single and average trial reliability for single leg balance testing on stable and unstable surfaces using dominant and nondominant limbs. DESIGN: Intrasession reliability. SETTING: Biomechanics laboratory. PARTICIPANTS: 70 healthy (35 men, 35 women), physically active young adults aged 22.8 ± 2.8 y divided into 3 subgroups (n = 10, 30, 30) across a 3-phase study. METHODS: 3 phases of single leg balance testing were performed. For phase 1, the duration of time each participant could maintain posture on each limb/surface were computed. Phase 2 considered performance for 6 cumulative time intervals (5s, 10s, 15s, 20s, 25s, 30s). Phase 3 served to solidify results of phase 2 by computing reliability of 15s trials. MAIN OUTCOME MEASURES: Overall stability index of the center of pressure and platform tilt. RESULTS: Intraclass correlation coefficients for phase 2 ranged from .74 (5s interval for nondominant limb on unstable surface) to .94 (20s interval for nondominant limb on stable surface). Phase 3 intraclass correlation coefficients ranged from .66 to .78 for single trial and .85 to .92 for 3 trial average with coefficients of variation ranging from 23.9% to 40.4% for single trial and 13.8% to 23.0% for 3 trial average. CONCLUSIONS: These results ultimately suggest 15s as the optimal trial duration to provide reliable measures while reducing compensatory event occurrence.

Isokinetic Testing: Why it is More Important Today than Ever.

Isokinetics is a proven method to train and objectively assess the capability of muscle groups, particularly at the knee. The current re-injury rates and less than optimal return to sport percentages seen following anterior cruciate ligament surgery highlights the need for greater focus on what tests and methods are used to make these critical decisions. Isokinetics remains the best single method to objectively determine dynamic muscle strength, power, rate of force development and endurance. These factors make it well-suited to play a crucial role in influencing the appropriate patient progression through a rehabilitation program and assisting in determining return to play readiness following injury or surgery. In this article we will discuss why we believe isokinetics is a useful and necessary testing method, and elucidate testing parameters and goals used during knee extension/flexion assessment.

Residual Effects of Same Day Lower Extremity Strength Training on Countermovement Jump Performance in Collegiate Women Athletes.

Balancing of strength programming intensity with sport demands is necessary to avoid excessive workloads that could inhibit performance. To expand previous jump height focused literature, this study evaluated whether countermovement jump (CMJ) movement strategies, including eccentric characteristics, might reveal CMJ execution strategy shifts to achieve similar afternoon CMJ height following a morning resistance training session (RTS). Fifteen collegiate women's soccer and volleyball athletes (18-24 years, 73.6 ± 8.4 kg, 1.74 ± 0.19 m) participating in an offseason RTS completed five CMJs during two afternoon sessions (48 h apart), one 4-6 h post morning RTS, and one on a rest day. The RTS consisted of 2 sets of 10 repetitions at 70-80% 1RM for the back squat, the front squat, and the forward lunge. Vertical ground reaction forces were recorded from which 13 outcome measures describing elements of the eccentric and concentric CMJ phases were computed. No significant differences in jump height (p = 0.427, d = 0.17) or outcome measures (p = 0.091-0.777, d = -0.07-0.21) between sessions with exception of a significant concentric phase time decrease (p = 0.026, d = 0.23) following the RTS were identified. Given the magnitude of the mean concentric phase time change (0.01 s), the result likely has limited practical meaning. As these results confirm previous CMJ height literature, practitioners have further evidence that a morning RTS does not interfere or enhance afternoon CMJ performance in athletic women.

Reliability of Upper Extremity Functional Performance Tests for the Non-overhead Athlete.

Background: While there have been reliability studies conducted on several upper extremity functional performance tests (UEFPT), there are several complicating factors that inhibit the ability to draw definitive consensus about the reliability of the tests in both females and males. Having reliability estimates for UEFPT in the same cohort facilitates direct comparison of their relative and absolute reliability. Purpose: To establish the test-retest reliability of the closed kinetic chain upper extremity stability test (CKCUEST), seated medicine ball chest pass test (SMBCPT) and hands-release push-up test (HRPUT) in a cohort of males and females with a history of non-overhead sport participation. A secondary purpose was to examine the associations between the three UEFPT. Study Design: Test-retest reliability, single cohort study. Methods: Forty adults (20 females, 20 males) with a history of non-overhead sport participation completed three UEFPT during two data collection sessions three to seven days apart. Measures of systematic bias, absolute reliability and relative reliability were computed between the sessions. Additionally, correlational analyses were conducted between the three UEFPT. Results: Only the UECKCST (both sexes) demonstrated significant (p≤ 0.003) second session performance improvements. All three tests exhibited excellent relative reliability (intraclass correlational coefficients ≥ 0.823) and except for the HRPUT in males, coefficients of variation were all below 8.8%. Except for a significant relationship (r=.691, p=0.001) between the UECKCST and SMBCPT for the females there were no other associations between the three UEFPT. Conclusion: All three UEFPT demonstrated sufficient reliability. Thus, all three assessments can be used for serial assessments to progress a patient through rehabilitation as well as contribute to the criteria used in making return to sport decisions. Level of Evidence: 3.

Reliability of Upper Extremity Functional Performance Tests for Overhead Sports Activities.

Background: There is lack of consensus on which tests, particularly upper extremity functional performance tests (FPT) that should be used for clinical decision making to progress a patient through a rehabilitation program or criteria for return to sport (RTS). Consequently, there is a need for tests with good psychometric properties that can be administered with minimal equipment and time. Purpose: (1) To establish the intersession reliability of several open kinetic chain FPT in healthy young adults with a history of overhead sport participation. (2) To examine the intersession reliability of the limb symmetry indices (LSI) from each test. Study Design: Test-retest reliability, single cohort study. Methods: Forty adults (20 males, 20 females) completed four upper extremity FPT during two data collection sessions three to seven days apart: 1) prone medicine ball drop test 90°shoulder abduction (PMBDT 90°), 2) prone medicine ball drop test 90°shoulder abduction/90° elbow flexion (PMBDT 90°-90°), 3) half-kneeling medicine ball rebound test (HKMBRT), 4) seated single arm shot put test (SSASPT). Measures of systematic bias, absolute reliability and relative reliability were computed between the sessions for both the original test scores and LSI. Results: Except for the SSASPT, all tests demonstrated significant (p ≤ 0.030) improvements in performance during the second session. Generally, for the medicine ball drop/rebound tests, the absolute reliability was the highest (less random error) for the HKMBRT, next the PMBDT 90°followed by PMBDT 90°-90°. Excellent relative reliability existed for the PMBDT 90°, HKMBRT, and SSASPT, whereas fair to excellent relative reliability for the PMBDT 90°-90°. The SSASPT LSI revealed the highest relative and absolute reliability. Conclusion: Two tests, HKMBRT and SSASPT demonstrated sufficient reliability; therefore, the authors' recommend those tests can be used for serial assessments to advance a patient through a rehabilitation program as well as criteria for progression to RTS. Level of Evidence: 3.

Objective and subjective measures to guide upper extremity return to sport testing: A modified Delphi survey.

OBJECTIVE: To identify which subjective and objective tests do content experts utilize to help guide return to sport (RTS) decision making for an athlete after an upper extremity (UE) injury? METHODS: A modified Delphi survey was utilized, including content experts in UE rehabilitation. Survey items were identified based on a literature review identifying current best evidence and practice for UE RTS decision making. Content experts (n = 52) were identified, having a minimum of 10 years of experience with rehabilitation of UE athletic injuries, and 5 years of experience using an UE RTS algorithm to guide decision making. RESULTS: Expert consensus was achieved on a combination of tests utilized within an UE RTS algorithm: 1. Tissue healing time frame is an important consideration in RTS decision making; 2. Patient reported outcome measures should be utilized specifically, DASH and NPRS 3. Strength is measured by handheld dynamometer and is an important consideration. 4. ROM should be utilized and is an important consideration. 5. Physical performance tests utilized include: Closed Kinetic Chain Upper Extremity Stability test, Seated shot-put test and lower extremity/core tests. CONCLUSIONS: This survey reached expert consensus on which subjective and objective measures to utilize to evaluate RTS readiness after UE injury.

The Need To Change Return to Play Testing in Athletes Following ACL Injury: A Theoretical Model.

The incidence of knee injuries in sport, particularly involving the ACL, appears to be increasing yearly, especially in younger age athletes. Even more concerning is the frequency of ACL reinjury also appears to be increasing year after year. Improving the objective criteria and testing methods used to determine return to play (RTP) readiness following ACL surgery is one aspect of the rehabilitation process that can significantly help in reducing reinjury rates. Currently, the majority of clinicians are still using post operative time frames as their number one criterion for clearance to RTP. This flawed method demonstrates an inadequate reflection of the true unpredictable, dynamic environment athletes are returning to participate in. In our clinical experience, objective testing to allow for clearance to sport participation following an ACL injury should incorporate neurocognitive and reactive testing due to the nature of the injury typically occurs because of failed control of unanticipated reactive movements. The purpose of this manuscript is to share a neurocognitive testing sequence we currently employ consisting of 8 tests in 3 categories: Blazepod tests, reactive shuttle run tests, and reactive hop tests. The use of a more dynamic reactive testing battery may decrease the reinjury rates when an athlete is cleared for participation by measuring readiness in chaotic circumstances that are more truly reflective of the sporting environment the athlete is working to return to and in the process give them a greater sense of confidence.

Neurocognitive and Reactive Return to Play Testing Protocol in Overhead Athletes Following Upper Extremity Injury.

The incidence of upper extremity (UE) injuries in sport, particularly with the shoulder and elbow in baseball/softball players, appears to be increasing yearly, especially in younger age athletes. Improving the objective criteria and testing methods used to determine return to play (RTP) readiness following non-operative or post-operative management of UE injuries is one aspect of the rehabilitation process that may significantly help in reducing reinjury rates. Currently, the majority of clinicians are still using post operative time frame and/or strength/range of motion as their main criteria for clearance to RTP following UE injury. This demonstrates an inadequate reflection of the actual unpredictable, dynamic environment athletes are returning to participate in. In our clinical experiences, objective testing to allow for clearance to sport participation should incorporate neurocognitive and reactive testing to promote improvements in the athlete's ability to dual task and focus/concentrate on the multi-dimensional tasks at hand. We know that neuroplastic changes occur following UE injury resulting in decreased proprioception and increased motor activation with simple UE tasks. Currently the research on UE return to play testing is limited. The purpose of this clinical commentary was to describe the utilization and provide reference values for a series of reactive neurocognitive UE tests, to assist with RTP, in high school and collegiate overhead athletes (baseball and softball) utilizing the Blaze Pod light system. The use of a more dynamic reactive testing battery may decrease the reinjury rates when an athlete is cleared for participation by measuring readiness in chaotic circumstances that are more reflective of the sporting environment the athlete is working to return to resulting in a greater sense of confidence, performance and prevention of reinjuries.

Differential sensing with arrays of de novo designed peptide assemblies.

Differential sensing attempts to mimic the mammalian senses of smell and taste to identify analytes and complex mixtures. In place of hundreds of complex, membrane-bound G-protein coupled receptors, differential sensors employ arrays of small molecules. Here we show that arrays of computationally designed de novo peptides provide alternative synthetic receptors for differential sensing. We use self-assembling α-helical barrels (αHBs) with central channels that can be altered predictably to vary their sizes, shapes and chemistries. The channels accommodate environment-sensitive dyes that fluoresce upon binding. Challenging arrays of dye-loaded barrels with analytes causes differential fluorophore displacement. The resulting fluorimetric fingerprints are used to train machine-learning models that relate the patterns to the analytes. We show that this system discriminates between a range of biomolecules, drink, and diagnostically relevant biological samples. As αHBs are robust and chemically diverse, the system has potential to sense many analytes in various settings.

Reliability of scapular classification in examination of professional baseball players.

BACKGROUND: Clinically evaluating the scapulothoracic joint is challenging. To identify scapular dyskinesis, clinicians typically observe scapular motion and congruence during self-directed upper extremity movements. However, it is unclear whether this method is reliable. QUESTIONS/PURPOSES: We therefore determined the interrater reliability of a scapular classification system in the examination of professional baseball players. METHODS: Seventy-one healthy uninjured professional baseball players between the ages of 18 and 32 years volunteered to participate. We used a digital video camera to film five repetitions of scapular plane elevation while holding a 2-pound weight. Four examiners then independently classified the motions on video into one of four types. Interrater reliability analysis using the kappa (k) statistic was performed for: (1) classifying each scapula into one of the four types; (2) classifying each scapula as being abnormal (Types I-III) or normal (Type IV); and (3) classifying both scapula as both being symmetric (both normal or both abnormal) or asymmetric (one normal, one abnormal). RESULTS: We found low reliability for all analyses. In classifying each scapula as one of the four types, reliability was k = 0.245 for the left limb and k = 0.186 for the right limb. When considering the dichotomous classifications (abnormal versus normal), reliability was k = 0.264 for left and k = 0.157 for right. For bilateral symmetry/asymmetric, reliability was k = 0.084. CONCLUSION: We found low reliability of visual observation and classification of scapular movement. CLINICAL RELEVANCE: Current evaluation strategies for evaluating subtle scapular abnormalities are limited. LEVEL OF EVIDENCE: Level III, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.

Ground reaction force patterns in plyometric push-ups.

Compared with lower extremity plyometrics, data concerning the loads and intensity associated with upper extremity plyometrics are limited. The purpose of this study was to compare vertical ground reaction force (vGRF) characteristics between the clap push-up and box drop push-ups from 3.8 cm (BD1), 7.6 cm (BD2), and 11.4 cm (BD3) heights and limbs (dominant, nondominant). Twenty-two healthy active male subjects (age 25.9 ± 1.3 years, height 1.8 ± 0.08 m, mass 87.6 ± 12 kg) performed 4 repetitions of each push-up variation in a random order. Four dependent variables, peak vGRF, time-to-peak vGRF, loading rate (LR), and propulsion rate (PR) were calculated for each extremity. Statistical analysis consisted of separate limb by variation repeated measures analysis of variance. In addition, ground contact time (GCT) was statistically compared between variations. The GCT for the clap push-up (p = 0.033) was significantly less than that for BD1 and BD2. No significant differences were revealed for time-to-peak vGRF (p = 0.717). Peak vGRF was significant between dominant and nondominant limbs (p = 0.045). Post hoc analysis of a significant limb by variation interaction in LR (p < 0.001) revealed the dominant limb to be significantly greater than the nondominant one in all 4 push-up variations. Furthermore, for both limbs, the clap LR was significantly greater than BD1, BD2, and BD3. The clap PR was significantly greater than BD1, BD2, and BD3. These data add rationale for determining upper extremity plyometric progression. The peak vGRFs are similar, and altering the box height did not affect peak vGRF. In contrast, the clap demonstrated the highest LR and PR suggesting that it may be a more powerful exercise than BD1, BD2, and BD3. The higher LR (Clap and BD3) for the dominant extremity illustrates bilateral disparity in the rate of eccentric loading.

Relationships between the seated single arm shot put test and Quick-DASH in patients being discharged from physical therapy.

BACKGROUND: Research examining the relationship between patient reported outcomes (PRO) and upper extremity functional performance tests (UEFPT) in patients with shoulder pathology are limited. OBJECTIVE: To assess the relationship between the seated single arm shot put test (SSASPT) and the PRO Quick-Disabilities of Arm, Shoulder, and Hand (DASH) in patients being discharged from physical therapy after shoulder injury or surgery. METHODS: Six physical therapists who regularly use the SSASPT and DASH from six different clinical sites provided SSASPT scores and completed Quick-DASH forms on 75 patients being discharged from rehabilitation following shoulder injury or surgery. Patients were grouped according to whether the involved shoulder was the dominant (n = 43) or nondominant (n = 32) limb. Three separate simple linear regression models, whole cohort and two patient groups, were created to determine the magnitude of the relationships (standardized betas) and change (betas) between DASH scores and the SSASPT limb symmetry index (LSI). RESULTS: Neither whole cohort nor two groups exhibited statistically significant (P > .05) relationships between LSI and Quick-DASH scores based upon the standardized betas (-0.197-0.038). Additionally, neither the standardized betas (z = 1.49, P = .135) nor betas (z = 1.28, P = .200) were statistically different between the two groups. CONCLUSIONS: The current study revealed no association between SSASPT and the Quick-DASH at discharge from physical therapy following shoulder injury or surgery. Consequently, it may be important to perform a battery of tests that include both subjective PRO and objective UEFPT tests to obtain a comprehensive perspective of the patient's functional and perceived status.

The Influence of Hip Flexion and Isokinetic Velocity on Hamstrings-Quadriceps Strength Ratios in Healthy Females.

Context: Measurements of the concentric hamstrings-quadriceps strength ratio (Hc:Qc) are almost exclusively recorded in the upright, seated position (hip flexion 80-100°) on an isokinetic dynamometer at angular velocities ranging from 30°/s to 360°/s. Further, there is a scarcity of data examining Hc:Qc ratio in females. Objective: To compare the effects of hip-flexion position (0°, 45°, and 90°) and isokinetic velocity (60°/s, 180°/s, and 300°/s) on knee-extension and knee-flexion torques and the Hc:Qc ratio of females. Design: Single-session, repeated measures. Setting: Biomechanics laboratory. Participants: Twenty-seven healthy young female adults. Intervention: Participants completed five repetitions of isokinetic, concentric knee-flexion and knee-extension at hip flexions of 0° (supine), 45° (midrange), and 90° (traditional), at 60°/s, 180°/s, and 300°/s. Main Outcome Measures: Knee extension and flexion average peak torque (PT) and resultant Hc:Qc ratios. Results: Knee-extension average PT was significantly influenced by isokinetic velocity but hip-flexion position was not. Compared to 90°, knee-flexion average PT was significantly greater in the 45° and 0° hip positions, coupled with greater average PT decreases between 60°/s and 180°/s than between 180°/s and 300°/s. Hc:Qc ratios in the 0° position were significantly greater than in the other positions and increased significantly as testing velocity increased. Conclusions: Exclusively using a seated, upright position during knee isokinetic testing on females may misrepresent knee strength at more-functional hip positions. We recommend evaluating isokinetic knee strength using a supine position to better reflect hip positions during daily and sporting activities, throughout movement specific velocities.

Glenohumeral joint rotation range of motion in competitive swimmers.

Much research has examined shoulder range of motion adaptations in overhead-unilateral athletes. Based on the void examining overhead-bilateral athletes, especially competitive swimmers, we examined shoulder external rotation, isolated internal rotation, composite internal rotation, and total arc of motion range of motion of competitive swimmers. The range of motion of registered competitive swimmers (n = 144, age = 12-61 years) was compared by limb (dominant, non-dominant), sex, and age group (youth, high school, college, masters). Significantly (P < 0.05) greater dominant external rotation was observed for both men and women high school and college swimmers, youth women swimmers, and men masters swimmers compared with the non-dominant limb. The isolated internal rotation (glenohumeral rotation), composite internal rotation (glenohumeral rotation plus scapulothoracic protraction), and total arc of motion (external rotation plus composite internal rotation) of the non-dominant limb was significantly greater than that of the dominant limb by sex and age group. Youth and high school swimmers demonstrated significantly greater composite internal rotation than college and masters swimmers. Youth swimmers displayed significantly greater total arc of motion than all other age groups. These data will aid in the interpretation of shoulder range of motion values in competitive swimmers during preseason screenings, injury evaluations and post-rehabilitation programmes, with the results suggesting that differences exist in bilateral external rotation, isolated internal rotation, composite internal rotation, and total arc of motion range of motion.

Reliability and validity of a novel Isokinetic Knee Dynamometer System.

PURPOSE: The aim of this work was to determine the intersession reliability and validity of a recently developed prototype Isokinetic Knee Dynamometer to assess isokinetic knee extension and flexion peak moments compared to a Biodex System 4 dynamometer. METHODS: Thirty- -five healthy participants performed two sessions (48-h separation) of bilateral concentric isokinetic knee extension and flexion on both isokinetic devices at 60 °/s (6 repetitions), 180 °/s (10 repetitions) and 240 °/s (15 repetitions). Dynamometer and limb order were randomized among participants while peak moment of each set was used for data analysis. RESULTS: The Isokinetic Knee Dynamometer had excellent relative reliability, comparable to the System 4, and both systems displayed acceptable absolute reliability. Proportional biases were observed favoring the System 4 during knee extension of both limbs at 60 °/s and the dominant limb at 180 °/s, and fixed biases favoring the Isokinetic Knee Dynamometer in seven conditions. Relative agreement between systems was good across all test conditions with the majority demonstrating excellent agreement. CONCLUSIONS: These data support the Isokinetic Knee Dynamometer as a reliable and valid knee isokinetic testing system. Due to its reduced system complexity, space requirements, and production cost, the Isokinetic Knee Dynamometer may increase the clinical utilization of isokinetic knee assessments. Finally, these data fill an existing isokinetics literature void with the results supporting similar and acceptable measurement properties jointly for dominant and non-dominant limbs and at the higher testing velocities considered.