Roger O. Kollock

Real-Time Intersession and Interrater Reliability of the Functional Movement Screen

Onate, JA, Dewey, T, Kollock, RO, Thomas, KS, Van Lunen, BL, DeMaio, M, and Ringleb, SI. Real-time intersession and interrater reliability of the functional movement screen. J Strength Cond Res 26(2): 408–415, 2012—The purpose of this study was to examine the real-time intersession and interrater reliability of the functional movement screen (FMS). The overall study consisted of 19 volunteer civilians (12 male, 7 female). The intersession reliability consisted of 12 men and 7 women, whereas 10 men and 6 women participated in the interrater reliability test session. Two raters (A and B) were involved in the interrater reliability aspect of this study. The FMS includes 7 tests: deep squat (DS), hurdle step (HS), in-line lunge (IL), shoulder mobility (SM), active straight leg raise (ASLR), trunk stability push-up (TSPU), and rotary stability (RS). Researchers analyzed the data via intraclass correlation (ICC). To determine the reliability of the intersession scoring of the FMS and the intrasession interrater scoring of the FMS a 2-way mixed effects model intraclass correlation coefficient (ICC3,1) was used for the continuous data, whereas a weighted Cohens kappa (κ) was used for the categorical data. The dependent variables were FMS total score (0–21 scale) and associated tests were DS, HS, IL, SM, ASLR, TSPU, and RS. Intersession reliability (ICC, SEM) and κ were as follows: FMS total score (0.92, 0.51), DS (κ = 0.69), HS (κ = 0.16), IL (κ = 0.69), SM (κ = 0.84), ASLR (κ = 0.69), TSPU (κ = 0.77), and RS (no covariance). Interrater reliability (ICC, SEM) and κ were as follows: FMS total score (0.98, 0.25), DS (κ = 1.0), HS (κ = 0.33), IL (κ = 0.88), SM (κ = 0.90), ASLR (κ = 0.88), TSPU (κ = 0.75), and RS (no covariance). The FMS total scores displayed high intersession and interrater reliabilities. Finally, with the exception of HS, all tasks displayed moderate to high intersession reliability and good to high interrater reliability.

The Reliability of Portable Fixed Dynamometry During Hip and Knee Strength Assessments

CONTEXT Insufficient lower extremity strength may be a risk factor for lower extremity injuries such as noncontact anterior cruciate ligament tears. Therefore, clinicians need reliable instruments to assess strength deficiencies. OBJECTIVE To assess the intrarater, interrater, intrasession, and intersession reliability of a portable fixed dynamometer in measuring the strength of the hip and knee musculature. DESIGN Crossover study. SETTING Sports medicine research laboratory. PATIENTS OR OTHER PARTICIPANTS Three raters (A, B, C) participated in this 2-phase study. Raters A and B tested 11 healthy college graduate students (2 men, 9 women) in phase 1. Raters A and C tested 26 healthy college undergraduate students (7 men, 19 women) in phase 2. MAIN OUTCOME MEASURE(S) The dependent variables for the study were hip adductor, hip abductor, hip flexor, hip extensor, hip internal rotator, hip external rotator, knee flexor, and knee extensor peak force. RESULTS The phase 1 intrasession intraclass correlation coefficients for sessions 1, 2, and 3 ranged from 0.88 to 0.99 (SEM = 0.08-3.02 N), 0.85 to 0.99 (SEM = 0.26-3.88 N), and 0.92 to 0.96 (SEM = 0.52-2.76 N), respectively. Intraclass correlation coefficients ranged from 0.57 to 0.95 (SEM = 1.72-13.15 N) for phase 1 intersession values, 0.70 to 0.94 (SEM = 1.42-9.20 N) for phase 2 intrarater reliability values, and 0.69 to 0.88 (SEM = 1.20-8.50 N) for phase 2 interrater values. CONCLUSIONS The portable fixed dynamometer showed good to high intrasession and intersession reliability values for hip and knee strength. Intrarater and interrater reliability were fair to high, except for hip internal rotation, which showed poor reliability.

Measures of functional performance and their association with hip and thigh strength.

CONTEXT Insufficient hip and thigh strength may increase an athletes susceptibility to injury. However, screening for strength deficits using isometric and isokinetic instrumentation may not be practical in all clinical scenarios. OBJECTIVE To determine if functional performance tests are valid indicators of hip and thigh strength. DESIGN Descriptive laboratory study. SETTING Research laboratory. PATIENTS OR OTHER PARTICIPANTS Sixty-two recreationally athletic men (n = 30, age = 21.07 years, height = 173.84 cm, mass = 81.47 kg) and women (n = 32, age = 21.03 years, height = 168.77 cm, mass = 68.22 kg) participants were recruited. INTERVENTION(S) During session 1, we measured isometric peak force and rate of force development for 8 lower extremity muscle groups, followed by an isometric endurance test. During session 2, participants performed functional performance tests. MAIN OUTCOME MEASURE(S) Peak force, rate of force development, fatigue index, hop distance (or height), work (joules), and number of hops performed during the 30-second lateral-hop test were assessed. The r values were squared to calculate r (2). We used Pearson correlations to evaluate the associations between functional performance and strength. RESULTS In men, the strongest relationship was observed between triple-hop work and hip-adductor peak force (r(2) = 50, P ≤ .001). Triple-hop work also was related to hip-adductor (r(2) = 38, P ≤ .01) and hip-flexor (r(2) = 37, P ≤ .01) rate of force development. For women, the strongest relationships were between single-legged vertical-jump work and knee-flexor peak force (r(2) = 0.44, P ≤ .01) and single-legged vertical-jump height and knee-flexor peak force (r(2) = 0.42, P ≤ .01). Single-legged vertical-jump height also was related to knee-flexor rate of force development (r(2) = 0.49, P ≤ .001). The 30-second lateral-hop test did not account for a significant portion of the variance in strength endurance. CONCLUSIONS Hop tests alone did not provide clinicians with enough information to make evidence-based decisions about lower extremity strength in isolated muscle groups.

A Meta-Analysis to Determine if Lower Extremity Muscle Strengthening Should Be Included in Military Knee Overuse Injury-Prevention Programs

CONTEXT  Knee overuse injuries are the most common musculoskeletal complaints in military trainees and are common in active-duty warfighters. Muscle strengthening is usually recommended; however, research is conflicting in this area, which makes it difficult to develop effective screening, prevention, and training interventions for warfighters. OBJECTIVE  To determine if lower extremity muscular weakness contributes to knee overuse injuries and identify specific muscular involvement. DATA SOURCES  We searched MEDLINE, PubMed, Web of Science, SPORTDiscus, CINAHL, and Military & Government Collection and reference lists of relevant articles published between January 1, 2000, and January 1, 2013. STUDY SELECTION  For inclusion, requirements were uninjured and injured groups; provision of the sample size, means, and standard deviations for all groups; identification of the specific muscles assessed; and clearly defined knee injury. DATA EXTRACTION  Sample size, sex, and muscle strength means and standard deviations. DATA SYNTHESIS  Twenty-five studies met these criteria. We used the Scottish Intercollegiate Guidelines Network algorithm to determine the appropriate tool for appraising article quality. Unweighted random-effects model meta-analyses were conducted. Separate meta-analyses were performed for the moderators of strength measurement scale (absolute or normalized muscle strength), muscle group, and sex. A weighted random-effects model with a Hedges g effect metric and 95% confidence intervals were used for comparison across studies. CONCLUSIONS  Our meta-analysis suggests that individuals with symptoms of a knee overuse injury have lower absolute and normalized hip muscle strength. Specifically, they had lower absolute hip external-rotator, knee-extensor, and knee-flexor strength, as well as lower normalized hip external-rotator, hip-extensor, and hip-abductor strength, compared with asymptomatic control participants. The findings suggest a possible link between lower hip and thigh strength and knee overuse injuries. Further research is needed to determine if weakness is a cause or a result of knee overuse injuries before screening and intervention can be developed for at-risk warfighters.

Effects of vehicle-ride exposure on cervical pathology—a meta-analysis

Research to date on the effect vehicle-ride exposure has on the development of cervical pathologies in mounted Warfighters is conflicting. The purpose of this study was to determine if the literature suggests a definite effect of vehicle-ride exposure on cervical pathology. Databases were searched using multiple combinations of select terms. Twelve studies meeting the inclusion criteria were included in the meta-analysis. The results of the meta-analysis revealed that overall vehicle-ride exposure was likely to increase cervical pathology (p=0.01, odds ratio=1.59, 95% CI=1.16−2.17). Using vehicle type as a moderator it was found that vehicle-ride exposure in ground-based vehicles (p=0.01, odds ratio=2.33, 95% CI=1.41−3.85) and fixed-wing aircraft (p=0.01, odds ratio =1.59, 95% CI=1.13−2.23) were likely to increase cervical pathology. Using operator/other personnel moderator it was found that in the populations tested, fighter pilots or fighter jet weapons systems operators were more likely to develop a cervical pathology (p<0.001, odds ratio=1.78, 95% CI=1.26−2.50). The available studies indicate an increase in cervical pathology for personnel exposed to ground-based vehicles and fixed-wing aircraft.

Peak Torque as an Indicator of Rapid Torque Production during Screening Examinations

Although the ability to produce force rapidly is an indispensable characteristic of optimal health and performance, screening for this very critical parameter of strength is difficult because of clinician time constraints. The purpose this study was to investigate relationships between peak torque (PT) and rate of torque development (RTD) at 0-30, 0-50, 0-100, and 0-200 ms in female collegiate soccer athletes. Seventeen female collegiate soccer athletes were recruited. Isometric PT and RTD were collected at the hip abductors (AB), hip adductors (AD), knee extensors (KE) and knee flexors (KF). The coefficients of determination were calculated to evaluate the association between PT and RTD. Normalized AB, AD and KF PT were significantly correlated to RTD at 0-30, 0-50, 0-100 and 0-200 ms, while KE PT was only significantly correlated to RTD at 0-100 and 0-200 ms. The results of this study indicate that PT is a viable, indirect indicator of early late phase RTD at separate time intervals at the AB, AD and KF. However, it is likely that other physiological factors coupled with PT are required to provide information on the rapid force production capabilities of the KFs and KEs based on the percent of common variance observed.

Vehicle Exposure and Spinal Musculature Fatigue in Military Warfighters: A Meta-Analysis

CONTEXT  Spinal musculature fatigue from vehicle exposure may place warfighters at risk for spinal injuries and pain. Research on the relationship between vehicle exposure and spinal musculature fatigue is conflicting. A better understanding of the effect of military duty on musculoskeletal function is needed before sports medicine teams can develop injury-prevention programs. OBJECTIVE  To determine if the literature supports a definite effect of vehicle exposure on spinal musculature fatigue. DATA SOURCES  We searched the MEDLINE, Military & Government Collection (EBSCO), National Institute for Occupational Safety and Health Technical Information Center, PubMed, and Web of Science databases for articles published between January 1990 and September 2015. STUDY SELECTION  To be included, a study required a clear sampling method, preexposure and postexposure assessments of fatigue, a defined objective measurement of fatigue, a defined exposure time, and a study goal of exposing participants to forces related to vehicle exposure. DATA EXTRACTION  Sample size, mean preexposure and postexposure measures of fatigue, vehicle type, and exposure time. DATA SYNTHESIS  Six studies met the inclusion criteria. We used the Scottish Intercollegiate Guidelines Network algorithm to determine the appropriate tool for quality appraisal of each article. Unweighted random-effects model meta-analyses were conducted, and a natural log response ratio was used as the effect metric. The overall meta-analysis demonstrated that vehicle exposure increased fatigue of the spinal musculature (P = .03; natural log response ratio = -0.22, 95% confidence interval = -0.42, -0.02). Using the spinal region as a moderator, we observed that vehicle ride exposure significantly increased fatigue at the lumbar musculature (P = .02; natural log response ratio = -0.27, 95% confidence interval = -0.50, -0.04) but not at the cervical or thoracic region. CONCLUSIONS  Vehicle exposure increased fatigue at the lumbar region.

Tissue Changes During Operational Load Bearing in UH-60 Aircrew Using Magnetic Resonance Imaging.

INTRODUCTION Warfighters involved in mounted operations often experience prolonged periods of tissue loading, leading to injury. Determining how anatomical structures are affected during loading aids in the prevention and treatment of injury. The purpose of this study was to develop a magnetic resonance imaging (MRI) compatible seat system that simulates a UH-60 Blackhawk in-flight sitting posture. METHODS Eight men were scanned with a 3.0 Tesla MRI. Scans were collected with and without 6.38 psi of pressure applied to the buttocks via two air bladders and an MRI-compatible robot controller system. RESULTS Scans revealed that 6.38 psi of pressure applied to the buttocks significantly decreases total soft-tissue thickness beneath the left and right ischial tuberosities by 3.6 and 3.8 mm, respectively. DISCUSSION At operational load bearing pressures seen in the UH-60, the soft tissue structures of the buttocks are compressed. These findings aid in our understanding of the etiology of repetitive trauma disorders in aircrew due to prolonged sitting. This study serves as the foundation for future work examining the anatomical changes associated with prolonged restricted sitting and other operational activities. A better understanding of the anatomical characteristics associated with mounted operations is invaluable to the prevention and treatment of injuries reported by warfighters and civilian populations.