The Relationship Between 2-Dimensional Knee-Valgus Angles During Single-Leg Squat, Single-Leg-Land, and Drop-Jump Screening Tests

Abstract

Context:Injuries to the anterior cruciate ligament (ACL) and patellofemoral joint (PFJ) are a significant problem in female athletes. A number of screening tasks have been used in the literature to identify those at greatest risk of injury. To date, no study has examined the relationship in 2-dimensional (2D) knee valgus between common screening tasks to determine whether individuals exhibit similar movement patterns across tasks.Objective:To establish whether frontal-plane projection angle (FPPA) during the single-leg squat (SLS), single-leg land (SLL), and drop jump (DJ) are related.Design:Cross-sectional study.Setting:University laboratory.Participants:52 national-league female football players and 36 national-league female basketball players.Main Outcome Measures:2D FPPA during the SLS, SLL, and DJ screening tasks.Results:Significant correlations were found between tasks. FPPA in the SLS was significantly correlated with SLL (r = .52) and DJ (r = .30), whereas FPPA in the SLL was also significantly correlated to DJ (r = .33). FPPA was significantly greater in the SLS than in the SLL (P < .001) and DJ (P < .001) and in the SLL than in the DJ (P < .001).Conclusion:The results showed that 2D FPPA is correlated across the SLS, SLL, and DJ tasks. However, significantly greater FPPA values in the unilateral tasks suggest that the DJ may not identify risk of injury in sports where primary injury mechanisms are during unilateral loading tasks. Therefore, it is recommended that both unilateral and bilateral tasks be included when screening for ACL and PFJ injury risk.

Comparison of Drop Jump and Tuck Jump Knee Joint Kinematics in Elite Male Youth Soccer Players: Implications for Injury Risk Screening

“…Additionally, due to financial costs and time-consuming nature of testing, many 3D motion capture systems are impractical for applied settings, especially when attempting to screen large groups of young players in the setting of a soccer academy. Secondly, the point of maximum knee flexion was not quantified using a sagittal plane camera; however, the chosen method of determining the lowest point of the landing task has been validated in previous research 16,27 . Finally, correlation does not imply causation, and further research is required to better understand the reason for the variability in strength of relationships across the different maturity groups.…”

“…Maximum knee flexion angle was determined from the frame which indicated the lowest point of the landing task as observed on the video using the analysis software; an approach that is in accordance with previous research 16,27 . The FPPA was measured once for each DVJ trial.…”

“…While research has examined biomechanical differences in a range of jump-landing screening tests, invariably these have involved bilateral versus unilateral comparisons and primarily included adults 15,16 . Minimal data currently exist examining differences in knee kinematics during commonly used bilateral jumping tasks, especially rebounding-based protocols, and in particular involving young athletes.…”

A qualitative screening tool to identify athletes with ‘high-risk’ movement mechanics during cutting: The cutting movement assessment score (CMAS)

“…This is particularly important when aiming to screen athletes who participate in sports such as soccer (82), handball (68), American football (39), badminton (46), and rugby (63), where directional changes are a primary action associated with-non contact ACL injuries. Furthermore, there are mixed findings whether examination of landing mechanics can identify athletes with poor cutting mechanics (1,13,51,67), with evidence suggesting an athlete's mechanics and "injury-risk profile" are task dependent (13,45,51,64). As such, screening side-step cutting technique, which is specific to the actions associated with non-contact ACL injuries in cutting sports (i.e.…”

Effect of Sand on Landing Knee Valgus During Single-Leg Land and Drop Jump Tasks: Possible Implications for ACL Injury Prevention and Rehabilitation

“…The test-retest reliability of these jumps has been previously established as good to excellent ICC (r = 0.89-0.92). 31 Participants then performed three trials for each jump task on each surface (land and sand) with a standardised rest phase between jumps. Jump tasks were performed in a randomised order using a computer-generated system, with the surface type counterbalanced in a repeated measures crossover design.…”