Craig A. Smith

Association of Y Balance Test Reach Asymmetry and Injury in Division I Athletes.

PURPOSE The Y balance test (YBT) is a screen of dynamic balance requiring stance leg balance while the contralateral leg reaches in anterior (ANT), posteromedial (PM), and posterolateral (PL) directions. YBT has been proposed as a screen for injury risk; however, limited research has examined the association between YBT and injury. The purpose of this study was to examine the association between YBT (asymmetry and composite score (CS)) and noncontact injury in a sample of Division I (DI) college athletes from multiple sports. METHODS DI college athletes were screened with the YBT during the preparticipation examination to determine asymmetry (absolute difference between legs in ANT, PL, and PM) and CS (summed average of right/left ANT, PL, and PM normalized to leg length). Participants were followed throughout the sport season, and noncontact injuries requiring athletic training staff intervention were recorded for analysis. Demographic variables between injured and uninjured athletes were assessed with independent t-tests. Receiver operating characteristic (ROC) curves determined optimal cut points for predicting injury on the basis of CS and asymmetry. CS was analyzed as a continuous variable, as ROC curves were unable to maximize sensitivity and specificity. Logistic regression models adjusted for sport and previous injury determined the odds of injury on the basis of asymmetry and CS. RESULTS One hundred and eighty-four participants were included in analysis; 81 were injured. ROC curves determined asymmetry >4 cm (sensitivity, 59%; specificity, 72%) as the optimal cut point for predicting injury. Only ANT asymmetry was significantly associated with noncontact injury (odds ratio, 2.33; 95% confidence interval, 1.15-4.76). CONCLUSIONS ANT asymmetry >4 cm was associated with increased risk of noncontact injury. CS in this sample of DI athletes was not associated with increased risk of injury.

Association of the Functional Movement Screen With Injuries in Division I Athletes

CONTEXT The Functional Movement Screen (FMS) evaluates performance in 7 fundamental movement patterns using a 4-point scale. Previous studies have reported increased injury risk with a composite score (CS) of 14/21 or less; these studies were limited to specific sports and injury definition. OBJECTIVE To examine the association between FMS CS and movement pattern scores and acute noncontact and overuse musculoskeletal injuries in division I college athletes. An exploratory objective was to assess the association between injury and FMS movement pattern asymmetry. DESIGN Prospective cohort. SETTING College athletic facilities. PARTICIPANTS 167 injury-free, college basketball, football, volleyball, cross country, track and field, swimming/ diving, soccer, golf, and tennis athletes (males = 89). INTERVENTION The FMS was administered during pre-participation examination. MAIN OUTCOME MEASURE Noncontact or overuse injuries that required intervention from the athletic trainer during the sport season. RESULTS FMS CS was not different between those injured (n = 74; 14.3 ± 2.5) and those not (14.1 ± 2.4; P = .57). No point on the ROC curve maximized sensitivity and specificity; therefore previously published cut-point was used for analysis with injury (≤ 14 [n = 92]). After adjustment, no statistically significant association between FMS CS and injury (odds ratio [OR] = 1.01, 95% CI 0.53-1.91) existed. Lunge was the only movement pattern that was associated with injury; those scoring 2 were less likely to have an injury vs those who scored 3 (OR = 0.21, 95% CI 0.08-0.59). There was also no association between FMS movement pattern asymmetry and injury. CONCLUSION FMS CS, movement patterns, and asymmetry were poor predictors of noncontact and overuse injury in this cohort of division I athletes.

Interrater and Intrarater Reliability of the Tuck Jump Assessment by Health Professionals of Varied Educational Backgrounds

Objective. The Tuck Jump Assessment (TJA), a clinical plyometric assessment, identifies 10 jumping and landing technique flaws. The study objective was to investigate TJA interrater and intrarater reliability with raters of different educational and clinical backgrounds. Methods. 40 participants were video recorded performing the TJA using published protocol and instructions. Five raters of varied educational and clinical backgrounds scored the TJA. Each score of the 10 technique flaws was summed for the total TJA score. Approximately one month later, 3 raters scored the videos again. Intraclass correlation coefficients determined interrater (5 and 3 raters for first and second session, resp.) and intrarater (3 raters) reliability. Results. Interrater reliability with 5 raters was poor (ICC = 0.47; 95% confidence intervals (CI) 0.33–0.62). Interrater reliability between 3 raters who completed 2 scoring sessions improved from 0.52 (95% CI 0.35–0.68) for session one to 0.69 (95% CI 0.55–0.81) for session two. Intrarater reliability was poor to moderate, ranging from 0.44 (95% CI 0.22–0.68) to 0.72 (95% CI 0.55–0.84). Conclusion. Published protocol and training of raters were insufficient to allow consistent TJA scoring. There may be a learned effect with the TJA since interrater reliability improved with repetition. TJA instructions and training should be modified and enhanced before clinical implementation.

Tuck Jump Assessment: An Exploratory Factor Analysis in a College Age Population

Abstract Lininger, MR, Smith, CA, Chimera, NJ, Hoog, P, and Warren, M. Tuck Jump Assessment: An exploratory factor analysis in a college age population. J Strength Cond Res 31(3): 653–659, 2017—Due to the high rate of noncontact lower extremity injuries that occur in the collegiate setting, medical personnel are implementing screening mechanisms to identify those athletes that may be at risk for certain injuries before starting a sports season. The tuck jump assessment (TJA) was created as a “clinician friendly” tool to identify lower extremity landing technique flaws during a plyometric activity. There are 10 technique flaws that are assessed as either having the apparent deficit or not during the TJA. Technique flaws are then summed up for an overall score. Through expert consensus, these 10 technique flaws have been grouped into 5 modifiable risk factors: ligament dominance, quadriceps dominance, leg dominance or residual injury deficits, trunk dominance (“core” dysfunction), and technique perfection. Research has not investigated the psychometric properties of the TJA technique flaws or the modifiable risk factors. The present study is a psychometric analysis of the TJA technique flaws to measure the internal structure using an exploratory factor analysis (EFA) using data from collegiate athletes (n = 90) and a general college cohort (n = 99). The EFA suggested a 3 factor model accounting for 46% of the variance. The 3 factors were defined as fatigue, distal landing pattern, and proximal control. The results differ from the 5 modifiable risk categories as previously suggested. These results may question the use of a single score, a unidimensional construct, of the TJA for injury screening.

Utility of FMS to Understand Injury Incidence in Sports: Current Perspectives

The Functional Movement Screen (FMS) is a popular movement screen used by rehabilitation, as well as strength and conditioning, professionals. The FMS, like other movement screens, identifies movement dysfunction in those at risk of, but not currently experiencing, signs or symptoms of a musculoskeletal injury. Seven movement patterns comprise the FMS, which was designed to screen fundamental movement requiring a balance between stability and mobility. The 7 movement patterns are summed to a composite FMS score. For an instrument to have wide applicability and acceptability, there must be high levels of reliability, validity, and accuracy. The FMS is certainly a reliable tool, and can be consistently scored within and between raters. Although the FMS has high face and content validity, the criterion validity (discriminant and convergent) is low. Additionally, the FMS does not appear to be studying a single construct, challenging the use of the summed composite FMS score. The accuracy of the FMS in screening for injury is also suspect, with low sensitivity in almost all studies, although specificity is higher. Finally, within the FMS literature, the concepts of prediction and association are conflated, combined with flawed cohort studies, leading to questions about the efficacy of the FMS to screen for injury. Future research on the use of the FMS, either the composite score or the individual movement patterns, to screen for injury or injury risk in adequately powered, well-designed studies are required to determine if the FMS is appropriate for use as a movement screen.

Comparison of Female Collegiate Athletes and College Age Cohort in Tuck Jump Assessment

Abstract Smith, CA, Olson, BK, Olson, LA, Chimera, NJ, and Warren, M. Comparison of female collegiate athletes and college age cohort in tuck jump assessment. J Strength Cond Res 31(4): 1048–1054, 2017—The tuck jump assessment (TJA) is a plyometric jumping assessment with 10 flaw criteria against which technique is assessed over a 10-second interval. The TJA has been reported as a tool for identifying neuromuscular deficits that increase risk for anterior cruciate ligament injury, but group specific data on female TJA scores are limited. No cut point has been developed for groups with different activity levels or participation in athletics. This study investigated the association between TJA score and athletic participation in college-aged females. One hundred twenty-one females (53 collegiate athletes and 68 college students) completed the TJA. TJA score was the sum of flaws for the 10 criteria observed, and the number of jumps was recorded. Poisson regression was used to assess the association between TJA score and number of jumps. The association between each of the 10 flaws between groups was assessed with the chi-square test. No significant association was found between groups for TJA score (mean ± SD: 4.66 ± 1.07 athletes; 5.45 ± 1.05 college cohort; p = 0.06; &bgr; = 0.82). Athletes jumped significantly more times (12.23 ± 1.04 athletes; 9.35 ± 1.04 college cohort). Athletes had a lower proportion of 2 flaws: “thighs do not reach parallel” and “pause between jumps.” Lower statistical power may limit interpretation of the remaining flaws. The lack of control of the number of jumps may impact TJA score. To improve the TJA usefulness on the field and clinic, the protocol may need to standardize the number of jumps.