Preseason Functional Test Scores are Associated with Future Sports Injury in Female Collegiate Athletes

Brumitt, J, Heiderscheit, B, Manske, R, Niemuth, PE, Mattocks, A, and Rauh, MJ. Preseason functional test scores are associated with future sports injury in female collegiate athletes. J Strength Cond Res 32(6): 1692–1701, 2018—Recent prospective cohort studies have reported preseason functional performance test (FPT) measures and associations with future risk of injury; however, the findings associated with these studies have been equivocal. The purpose of this study was to determine the ability of a battery of FPTs as a preseason screening tool to identify female Division III (D III) collegiate athletes who may be at risk for a noncontact time-loss injury to the lower quadrant (LQ = low back and lower extremities). One hundred six female D III athletes were recruited for this study. Athletes performed 3 FPTs: standing long jump (SLJ), single-leg hop (SLH) for distance, and the lower extremity functional test (LEFT). Time-loss sport-related injuries were tracked during the season. Thirty-two (24 initial and 8 subsequent) time-loss LQ injuries were sustained during the study. Ten of the 24 initial injuries occurred at the thigh and knee. At-risk athletes with suboptimal FPT measures (SLJ #79% ht; (B) SLH #64% ht; LEFT $118 seconds) had significantly greater rates of initial (7.2 per 1,000 athletic exposures [AEs]) and total (7.6 per 1,000 AEs) time-loss thigh or knee injuries than the referent group (0.9 per 1,000 AEs; 1.0 per 1,000 AEs, respectively). At-risk athletes were 9 times more likely to experience a thigh or knee injury (odds ratio [OR] = 9.7, confidence interval [CI]: 2.3–39.9; p = 0.002) than athletes in the referent group. At-risk athletes with a history of LQ sports injury and lower off-season training habits had an 18-fold increased risk of a time-loss thigh or knee injury during the season (adjusted OR = 18.7, CI: 3.0–118.1; p = 0.002). This battery of FPTs appears useful as a tool for identifying female D III athletes at risk of an LQ injury, especially to the thigh or knee region

Influence of ultrasound machine settings on quantitative measures derived from spatial frequency analysis of muscle tissue

Background Ultrasound is a powerful tool for diagnostic purposes and provides insight into both normal and pathologic tissue structure. Spatial frequency analysis (SFA) methods characterize musculoskeletal tissue organization from ultrasound images. Both sonographers in clinical imaging and researchers may alter a minimized range of ultrasound settings to optimize image quality, and it is important to know how these small adjustments of these settings affect SFA parameters. The purpose of this study was to investigate the effects of making small adjustments in a typical default ultrasound machine setting on extracted spatial frequency parameters (peak spatial frequency radius (PSFR), Mmax, Mmax%, and Sum) in the biceps femoris muscle. Methods Longitudinal B-mode images were collected from the biceps femoris muscle in 36 participants. The window depth, foci locations, and gain were systematically adjusted consistent with clinical imaging procedures for a total of 27 images per participant. Images were analyzed by identifying a region of interest (ROI) in the middle portion of the muscle belly in a template image and using a normalized two-dimensional cross-correlation technique between the template image and subsequent images. The ROI was analyzed in the frequency domain using conventional SFA methods. Separate linear mixed effects models were run for each extracted parameter. Results PSFR was affected by modifications in focus location only (p \u3c 0.001) with differences noted between all locations. Mmax% was influenced by the interaction of gain and focus location (p \u3c 0.001) but was also independently affected by increasing window depth (p \u3c 0.001). Both Mmax and Sum parameters were sensitive to small changes in machine settings with the interaction of focus location and window depth (p \u3c 0.001 for both parameters) as well as window depth and gain (p \u3c 0.001 for both) influencing the extracted values. Conclusions Frequently adjusted imaging settings influence some SFA statistics. PSFR and Mmax% appear to be most robust to small changes in image settings, making them best suited for comparison across individuals and between studies, which is appealing for the clinical utility of the SFA method

Lower Extremity Functional Tests and Risk of Injury in Division III Collegiate Athletes

Purpose/Background: Functional tests have been used primarily to assess an athlete’s fitness or readiness to return to sport. The purpose of this prospective cohort study was to determine the ability of the standing long jump (SLJ) test, the single-leg hop (SLH) for distance test, and the lower extremity functional test (LEFT) as preseason screening tools to identify collegiate athletes who may be at increased risk for a time-loss sports-related low back or lower extremity injury. Methods: A total of 193 Division III athletes from 15 university teams (110 females, age 19.1 ± 1.1 y; 83 males, age 19.5 ± 1.3 y) were tested prior to their sports seasons. Athletes performed the functional tests in the following sequence: SLJ, SLH, LEFT. The athletes were then prospectively followed during their sports season for occurrence of low back or LE injury. Results: Female athletes who completed the LEFT in 118 s were 6 times more likely (OR=6.4, 95% CI: 1.3, 31.7) to sustain a thigh or knee injury. Male athletes who completed the LEFT in 100 s were more likely to experience a time-loss injury to the low back or LE (OR=3.2, 95% CI: 1.1, 9.5) or a foot or ankle injury (OR=6.7, 95% CI: 1.5, 29.7) than male athletes who completed the LEFT in 101 s or more. Female athletes with a greater than 10% side-to-side asymmetry between SLH distances had a 4-fold increase in foot or ankle injury (cut point: \u3e10%; OR=4.4, 95% CI: 1.2, 15.4). Male athletes with SLH distances (either leg) at least 75% of their height had at least a 3-fold increase (OR=3.6, 95% CI: 1.2, 11.2 for the right LE; OR=3.6, 95% CI: 1.2, 11.2 for left LE) in low back or LE injury. Conclusions: The LEFT and the SLH tests appear useful in identifying Division III athletes at risk for a low back or lower extremity sports injury. Thus, these tests warrant further consideration as preparticipatory screening examination tools for sport injury in this population. Clinical Relevance: The single-leg hop for distance and the lower extremity functional test, when administered to Division III athletes during the preseason, may help identify those at risk for a time-loss low back or lower extremity injury

The Lower-Extremity Functional Test and Lower-Quadrant Injury in NCAA Division III Athletes: A Descriptive and Epidemiologic Report

Context: The Lower-Extremity Functional Test (LEFT) has been used to assess readiness to return to sport after a lower extremity injury. Current recommendations suggest that women should complete the LEFT in 135 s (average; range 120-150 s) and men should complete the test in 100 s (average; range 90-125 s). However, these estimates are based on limited data and may not be reflective of college athletes. Thus, additional assessment, including normative data, of the LEFT in sport populations is warranted. Objective: To examine LEFT times based on descriptive information and off-season training habits in NCAA Division III (Dill) athletes. In addition, this study prospectively examined the LEFT’S ability to discriminate sport-related injury occurrence. Design: Descriptive epidemiology. Setting: Dill university. Subjects: 189 Dill college athletes (106 women, 83 men) from 15 teams. Main Outcome Measures: LEFT times, preseason questionnaire, and time-loss injuries during the sport season. Results: Men completed the LEFT (105 ± 9 s) significantly faster than their female counterparts (117 ± 10 s) (P \u3c .0001). Female athletes who reported \u3e3-5 h/wk of plyometric training during the off-season had significantly slower LEFT scores than those who performed \u3c3 h/wk of plyometric training (P - -03). The overall incidence of a lower-quadrant (LQ) time-loss injury for female athletes was 4.5/1000 athletic exposures (AEs) and 3.7/1000 AEs for male athletes. Female athletes with slower LEFT scores (\u3e118 s) experienced a higher rate of LQ time-loss injuries than those with faster LEFT scores (\u3c117 s) (P = .03). Conclusion: Only off-season plyometric training practices seem to affect LEFT score times among female athletes. Women with slower LEFT scores are more likely to be injured than those with faster LEFT scores. Injury rates in men were not influenced by performance on the LEFT

Differences in lower-extremity muscular activation during walking between healthy older and young adults

a b s t r a c t Previous studies have identified differences in gait kinetics between healthy older and young adults. However, the underlying factors that cause these changes are not well understood. The objective of this study was to assess the effects of age and speed on the activation of lower-extremity muscles during human walking. We recorded electromyography (EMG) signals of the soleus, gastrocnemius, biceps femoris, medial hamstrings, tibialis anterior, vastus lateralis, and rectus femoris as healthy young and older adults walked over ground at slow, preferred and fast walking speeds. Nineteen healthy older adults (age, 73 ± 5 years) and 18 healthy young adults (age, 26 ± 3 years) participated. Rectified EMG signals were normalized to mean activities over a gait cycle at the preferred speed, allowing for an assessment of how the activity was distributed over the gait cycle and modulated with speed. Compared to the young adults, the older adults exhibited greater activation of the tibialis anterior and soleus during midstance at all walking speeds and greater activation of the vastus lateralis and medial hamstrings during loading and mid-stance at the fast walking speed, suggesting increased coactivation across the ankle and knee. In addition, older adults depend less on soleus muscle activation to push off at faster walking speeds. We conclude that age-related changes in neuromuscular activity reflect a strategy of stiffening the limb during single support and likely contribute to reduced push off power at fast walking speeds

New Concepts A dynamical systems approach to lower extremity running injuries

Abstract In this paper, we are presenting an alternative approach to the investigation of lower extremity coupling referred to as a dynamical systems approach. In this approach, we calculate the phase angle of each segment and joint angle. Pairing the key segment/ joint motions, we use phase angles to determine the continuous relative phase and the variability of the continuous relative phase. Data from two studies illustrate the ecacy of the dynamical systems approach. Individuals who were asymptomatic, even though they may have anatomical aberrant structural problems (i.e. high Q-angle vs low Q-angle) showed no dierences in the pattern of the continuous relative phase or in the variability of the continuous phase. However, dierences in the variability of the continuous relative phase were apparent in comparing individuals who were symptomatic with patellofemoral pain with non-injured individuals. Patellofemoral pain individuals showed less variability in the continuous relative phase of the lower extremity couplings than did the healthy subjects. We hypothesize that the lower variability of the couplings in the symptomatic individuals indicates repeatable joint actions within a very narrow range. Relevance We claim that the traditional view of the variability of disordered movement is not tenable and suggest that there is a functional role for variability in lower extremity segment coupling during locomotion. While the methods described in this paper cannot determine a cause of the injury, they may be useful in the detection and treatment of running injuries.

Semimembranosus Muscle Injuries In Sport. A Practical MRI use for Prognosis

The aim of this work was to study semimembranosus musculotendinous injuries (SMMTI) and return to play (RTP). The hypothesis is that some related anatomic variables of the SM could contribute to the prognosis of RTP. The retrospective study was done with 19 athletes who suffered SMMTI from 2010 to 2013 and in whose cases a 3.0T MRI was performed. We evaluated the A, B, C SM regions damaged and calculated the relative length and percentage of cross-sectional area (CSA) affected. We found the correlation of these variables with RTP. The data was regrouped in those cases where the part C of the injury was of interest and those in which the C region was unscathed (pooled parts). We used the Mann-Whitney U test and there was a higher RTP when the injury involved the C part of SM (49.1 days; 95% CI [27.6- 70.6]) compared to non-C-part involvement (27.8 days; 95% CI [19.5-36.0]). The SMMTI with longer RTP typically involves the C part with or without participation of the B part. In daily practice, the appearance on MRI of an altered proximal tendon of the SM indicates that the injury affects the C region and therefore has a longer RTP

The effects of hip- vs. knee-dominant hamstring exercise on biceps femoris morphology, strength, and sprint performance: a randomized intervention trial protocol

Background The hamstrings are an important muscle group that contribute to horizontal force during sprint acceleration and are also the most injured muscle group in running-based sports. Given the significant time loss associated with hamstrings injury and impaired sprinting performance following return to sport, identifying exercises that drive adaptations that are both protective of strain injury and beneficial to sprint performance is important for the strength and conditioning professional. This paper describes the study protocol investigating the effects of a 6-week training program using either the hip-dominant Romanian deadlift (RDL) or the knee-dominant Nordic hamstring exercise (NHE) on hamstring strain injury risk factors and sprint performance. Methods A permuted block randomized (1:1 allocation) intervention trial will be conducted involving young, physically-active men and women. A target sample size of 32 will be recruited and enrolled participants will undergo baseline testing involving extended-field-of-view ultrasound imaging and shear wave elastography of the biceps femoris long head muscle, maximal hamstrings strength testing in both the RDL and NHE, and on-field sprint performance and biomechanics. Participants will complete the 6-week training intervention using either the RDL or NHE, according to group allocation. Baseline testing will be repeated at the end of the 6-week intervention followed by 2 weeks of detraining and a final testing session. The primary outcome will be regional changes in fascicle length with secondary outcomes including pennation angle, muscle cross sectional area, hamstring strength, and maximal sprint performance and biomechanics. An exploratory aim will determine changes in shear wave velocity. Discussion Despite extensive research showing the benefits of the NHE on reducing hamstring strain injury risk, alternative exercises, such as the RDL, may offer similar or potentially even greater benefits. The findings of this study will aim to inform future researchers and practitioners investigating alternatives to the NHE, such as the RDL, in terms of their effectiveness in reducing rates of hamstring strain injury in larger scale prospective intervention studies

STepped exercise program for patients with knee OsteoArthritis (STEP-KOA): protocol for a randomized controlled trial

Background: Physical therapy (PT) and other exercise-based interventions are core components of care for knee osteoarthritis (OA), but both are underutilized, and some patients have limited access to PT services. This clinical trial is examining a STepped Exercise Program for patients with Knee OsteoArthritis (STEP-KOA). This model of care can help to tailor exercise-based interventions to patient needs and also conserve higher resource services (such as PT) for patients who do not make clinically relevant improvements after receiving less costly interventions. Methods / Design: Step-KOA is a randomized trial of 345 patients with symptomatic knee OA from two Department of Veterans Affairs sites. Participants are randomized to STEP-KOA and Arthritis Education (AE) Control groups with a 2:1 ratio, respectively. STEP-KOA begins with 3 months of access to an internet-based exercise program (Step 1). Participants not meeting response criteria for clinically meaningful improvement in pain and function after Step 1 progress to Step 2, which involves bi-weekly physical activity coaching calls for 3 months. Participants not meeting response criteria after Step 2 progress to in-person PT visits (Step 3). Outcomes will be assessed at baseline, 3, 6 and 9 months (primary outcome time point). The primary outcome is the Western Ontario and McMasters Universities Osteoarthritis Index (WOMAC), and secondary outcomes are objective measures of physical function. Linear mixed models will compare outcomes between the STEP-KOA and AE control groups at follow-up. We will also evaluate patient characteristics associated with treatment response and conduct a cost-effectiveness analysis of STEP-KOA. Discussion: STEP-KOA is a novel, efficient and patient-centered approach to delivering exercise-based interventions to patients with knee OA, one of the most prevalent and disabling health conditions. This trial will provide information on the effectiveness of STEP-KOA as a novel potential model of care for treatment of OA