
==== Front
Int J Sports Phys Ther
Int J Sports Phys Ther
2159
International Journal of Sports Physical Therapy
2159-2896
NASMI Website: International Journal of Sports Physical Therapy

34123542
23553
10.26603/001c.23553
Clinical Commentary/Current Concept Review
Noncontact Knee Ligament Injury Prevention Screening in Netball: A Clinical Commentary with Clinical Practice Suggestions for Community-Level Players
Clark Nicholas C PhD, MCSP, MMACP, CSCS 1
1 School of Sport, Rehabilitation, and Exercise Sciences University of Essex https://ror.org/02nkf1q06
Corresponding author: Nicholas C. Clark, PhD, MCSP, MMACP, CSCS. Lecturer (Education and Research) - Physiotherapy. School of Sport, Rehabilitation, and Exercise Sciences. University of Essex. Wivenhoe Park, Colchester, Essex, CO4 3SQ. United Kingdom. n.clark@essex.ac.uk
1 6 2021
2021
16 3 911929
4 8 2020
22 4 2021
© The Author(s)
https://creativecommons.org/licenses/by-nc-sa/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike License (4.0) which permits non-commercial use, distribution, and reproduction in any medium, provided the original author and source are credited. If you remix, transform, or build upon this work, you must distribute your contributions under the same license as the original.

Netball is a predominantly female team court-sport which is played worldwide. Netball is becoming more popular in the United States following its countrywide introduction to schools and community centers. A unique characteristic of netball is the footwork rule which restricts players to a one-step landing after catching the ball. Most netball landings are single-leg landings resulting in high vertical ground reaction forces and high skeletal tissue forces. Thus, high-risk landing events that have the biomechanical potential for injury occur frequently. Noncontact knee ligament injuries are common following a knee abduction collapse when landing. Because the consequences of noncontact knee ligament injury are profound, strategies are needed to mitigate the burden of such injury for players, teams, and society.

The purpose of this clinical commentary is to demonstrate how theoretical principles, different types of research, and different levels of evidence underpin a rational clinical reasoning process for developing noncontact knee ligament injury prevention screening procedures in netball. The theoretical principles that are discussed in this commentary include injury control, the sequence of prevention, principles of screening in injury prevention, the multifactorial model of injury etiology, complex systems theory, and systems science. The different types of research that are reviewed include descriptive and analytic-observational studies. The different levels of evidence that are discussed include prospective studies, cross-sectional studies, and clinicians’ own kinesiological modelling. Subsequently, an integrated approach to the evidence-informed development of noncontact knee ligament injury prevention screening procedures is presented. Clinical practice suggestions include a selection of evidence-informed screening tests that are quickly and easily implemented with netball players in local communities. The need for repeated screening at strategic timepoints across a season/year is explained. Sports physical therapists will find this commentary useful as an example for how to undertake clinical reasoning processes that justify the content of screening procedures contributing to noncontact knee ligament injury prevention in community-level netball.

Level of Evidence

5

screening
netball
ligament
knee
injury prevention
==== Body
pmcBACKGROUND AND PURPOSE

Netball is a predominantly female team sport with millions of players across 117 countries.1 Netball evolved from women’s basketball in the 1890s, was first played in England in 1895, and later became popular across the British Commonwealth.2 In England in 2017, there were 180,200 adult netball players3 which increased to 321,200 players by 2019.4 In 2018, there were 486,618 registered netball players in Australia5 and 145,000 registered players in New Zealand.6 In the United States (US), netball is a relatively new sport which gained popularity in the 1980s.7 Recently, Miami hosted the World University Netball Championships in 20168 and the US Open Netball Championships attracted over 100,000 viewers in 2017.7 Now, Netball America has members in 33 states7 and a new high-performance development pathway exists following the success of the US University Netball Team.9 Community-level netball participation in America is expected to grow following netball’s countrywide introduction to schools and community centers and tournaments at venues such as Madison Square Garden.7 With increased sport participation comes an increase in injury frequency.10–1212 Because of growing participation in netball in America, it is prudent for sports physical therapists to become familiar with the nature of the game and to consider primary injury control interventions with community-level players.

Netball is a court-based team game played over 15-minute quarters.13 Netball is played on indoor and outdoor courts and requires rapid acceleration, deceleration, and change-of-direction running along with jumping, leaping, and ball throwing/catching when attempting to score a goal in the opponent’s territory.13–15 A unique characteristic of netball is the ‘footwork rule’ which restricts players to a one-step landing after catching the ball.13 In other words, after touching down with one foot, players can only take one more step with the other foot to decelerate the body; after this, players may pivot on the touchdown foot before passing the ball to a teammate.13 The requirement to obey the footwork rule and stop suddenly with one step results in frequent single-leg landing (SLL) with vertical ground reaction force (VGRF) ranging from 3.516 to 5.717 times bodyweight (BW). The VGRF is of interest because it contributes to shear, compression, and rotation forces experienced by the lower-limb joints18,19 and because SLL and double-leg landing (DLL) are involved in 27.1-73.8% of injury events.20–23

Knee injuries account for substantial proportions of netball lower-limb injuries.21,22,24,25 Across studies, the majority of netball knee injuries are of a noncontact nature20,21,23,26,27 (Table 1). Trauma accounts for 26% of knee injuries referred to the emergency room26 and approximately one-third of netball-related hospitalizations.28 Anterior cruciate ligament (ACL) and meniscus tears occur in netball with a respective frequency of 17.2-22.4% and 4.5-32.7%.24,26 When comparing netball to basketball, female ACL sprains and meniscus tears demonstrate higher proportions in netball (17.2%, 4.5%) than basketball (11.1%, 4.1%).24 Considering ACL-reconstruction (ACLR) incidence between sports, a higher rate of ACLR is also evident in netball (188/100,000 participants) than basketball (109/100,000 participants).29 Anterior cruciate ligament and meniscus injuries result in profound consequences such as physical disability,28,30 substantial healthcare costs,29–32 disrupted academic studies,33,34 premature retirement from netball,35 post-trauma osteoarthritis,36,37 and depression.38,39 Risk of suicide can also exist after sports injuries.40,41 Because of such consequences, interventions are needed to mitigate the burden of knee ligament injury for players, teams, and society, and prolong players’ safe netball participation across the lifespan.

60348 Table 1: Definitions of contact, indirect contact, and noncontact knee injury*

Classification and Definition	Example	
 	 	
Contact injury		
Following contact with the player’s knee from an opponent or some external object	When a direct blow to the player’s knee occurs from an opponent who collides with the player following a slip/trip/fall.	
 	 	
Indirect contact injury	 	
Following contact with another part of the player’s body (e.g. trunk) from an opponent or some external object	When the player and an opponent are side-by-side and jumping upwards to contest for the ball and the opponent ‘bumps’ the player’s shoulder	
 	 	
Noncontact injury		
Following an athletic maneuver without any contact from an opponent or some external object	When a player decelerates suddenly when landing from a leap or cutting to change direction	
 	 	
*Modified from references: 27, 66, 74

The purpose of this clinical commentary is to demonstrate how theoretical principles, different types of research, and different levels of evidence underpin a rational clinical reasoning process for developing noncontact knee ligament injury prevention screening procedures in netball. An understanding of theoretical principles that support clinical practice is critical for designing evaluation and treatment interventions, deploying such interventions in the correct clinical context at the right time, and setting clinicians’ and athletes’ expectations appropriately relative to desired outcomes. This commentary will discuss how theoretical principles and different levels of evidence42 can be translated to and applied within sports physical therapy practice for primary prevention screening for noncontact knee ligament injury in community-level netball. Several paradigms will illustrate the implications of selected theoretical principles for such practice, including stages of injury control,43–45 sequence of prevention,46–49 principles of screening in injury prevention,50 multifactorial model of injury etiology,51 complex systems theory,52 and systems science.53,54 This commentary is original because no similar work exists in the netball literature. Sports physical therapists will find this commentary useful as an example for how to undertake clinical reasoning processes that justify the content of screening procedures contributing to noncontact knee ligament injury prevention in community-level netball.

DESCRIPTION OF THEORETICAL PRINCIPLES

Stages of Injury Control

Injury control refers to preventing or reducing the severity of injury43,45 and includes prevention, acute care, and rehabilitation phases of healthcare.44,45 Injury prevention refers to primary prevention of injury; that is, prevention of first-time injury to a bodypart.46,55 Injury prevention includes all countermeasures to eliminate or minimize the occurrence of injury.43,46 Injury prevention, therefore, does not refer to literal prevention of all injury cases but the prevention of as many cases as possible.43,46,55 Injury prevention seeks to reduce the probability of sustaining an injury rather than to achieve certainty that all cases can be averted.44,46,56 For the sports physical therapist, practice which recognizes prevention of all noncontact knee ligament injuries across time is not possible relative to probability theory (the likelihood that one event will occur given all possible outcomes)57,58 facilitates action from a place of scientifically-informed realistic intention and good conscience.59

Sequence of Prevention

Injury prevention includes evaluation and intervention procedures that combine to decrease the probability for and incidence of injury.44,46 The “sequence of prevention” refers to a process intended to culminate in such outcomes.49 The process includes four steps: 1. establish the incidence and severity of injury (epidemiology); 2. establish the factors contributing to and mechanisms of injury; 3. introduce prevention countermeasures (interventions); 4. assess intervention effectiveness by repeating step one.49 This process has been elaborated upon by other researchers,48 and correspond to long-standing public health disease prevention models.44,46 This commentary addressed step one (above) by establishing the frequency of ACL injury and ACLR in netball. This commentary addresses step two (below) by considering noncontact knee ligament injury mechanisms (i.e. mechanics of injury) and the factors associated with them (i.e. etiology of injury). The implication is that when a thorough undertaking of step two has occurred the sports physical therapist can consider appropriate evaluation (screening) procedures that, in turn, inform the content of step three and its interventions.44,46

Principles of Screening in Injury Prevention

In medicine, screening is a process to identify the presence or absence of disease.60 In sports medicine, the analogy is screening as a process to identify the presence or absence of injury.50 In injury prevention, the intent is to intervene before an injury occurs rather than diagnose an existing injury.50 Screening in injury prevention, therefore, is a process to identify characteristics (factors) that increase athletes’ probability of sustaining an injury.50 These characteristics are then termed ‘risk factors’.51,58 Risk factors are intrinsic (inside) and extrinsic (outside) to the player.46,49,61 In netball, examples of intrinsic and extrinsic risk factors for noncontact knee ligament injury appear in Table 2. Risk factors are also modifiable and nonmodifiable (Table 2).62 Modifiable risk factors (e.g. muscle strength) and nonmodifiable risk factors (e.g. age) can and cannot be altered with conservative interventions, respectively.62 For the sports physical therapist, the implication of intrinsic/extrinsic and modifiable/nonmodifiable risk factors is that the type and number of risk factors included in a screening test battery requires careful consideration. This consideration ensures the most clinically-amenable risk factors are evaluated and screening procedures are performed time-efficiently.

60345 Table 2: Examples of intrinsic and extrinsic risk factors for noncontact knee ligament injury in netball

Intrinsic Risk Ractors	Extrinsic Risk Factors	
Modifiable	Nonmodifiable	Modifiable	Nonmodifiable	
 	 	 	 	
Joint stiffness	Age	Indoor climate	Outdoor weather	
 	 	 	 	
Muscle strength	Sex	Playing surface		
 	 	 	 	
Balance	Femoral intercondylar			
	notch width			
 	 	 	 	
Neurocognitive	General joint			
performance	hypermobility			
 	 	 	 	
Landing movement				
pattern				
 	 	 	 	

Multifactorial Model of Injury Etiology

Because the probability of sustaining an injury is influenced by a combination of intrinsic and extrinsic risk factors, the etiology (cause) of injury is multifactorial.51,63 A combination of intrinsic (‘predisposing’) risk factors can sensitize a player to injury,51,64 while a combination of extrinsic (‘necessary’) risk factors must be present for an injury to occur.51,64 Therefore, the temporal relationship of risk factors is critical: some combination of intrinsic and extrinsic risk factors must exist before an injury event can happen (Figure 1).51,64 When a combination of factors produces an injury event within a specific situation, the factors are termed a “sufficient cause”.51,63,64 Screening to determine the presence/absence of intrinsic risk factors, therefore, relates to identifying an athlete predisposed to injury (“predisposed athlete”)51,65,66 (Figure 1). When a predisposed athlete enters a situation containing extrinsic risk factors, the athlete becomes susceptible to injury (“susceptible athlete”)51,65,66 (Figure 1). When the intrinsic and extrinsic risk factors interact within a specific situation as a sufficient cause, an injury event manifests (Figure 1).50,63,65,67 Therefore, for the sports physical therapist in netball, injury prevention screening is about identifying the predisposed player possessing intrinsic risk factors for noncontact knee ligament injury before entering a competitive environment (e.g. outdoor court), context (e.g. league match), or situation (e.g. offensive play).

60346 Figure 1: Example recursive and multifactorial model of netball noncontact knee ligament injury etiology (Modified from references 51, 65-67)

Complex Systems Theory

A complex system is a collection of interacting components where the behavior of the whole system cannot be predicted with 100% accuracy from the behavior (status) of one component alone.52,68,69 Given the human body is composed of multiple systems (e.g. skeletal, muscular, nervous, etc.) where each system itself is composed of many parts, an athlete is, by definition, a complex system. A netball player’s physiological (e.g. hydration levels, glycogen levels), physical (e.g. joint range-of-motion [ROM], muscle strength), and psychoemotional (e.g. stress, anxiety) status can change between matches, across the season, and across the off-season. A netball match’s environment (e.g. outdoor vs. indoor court) and context (e.g. annual league vs. weekend tournament) can alter from week-to-week. A netball player, therefore, competes within repeating (recursive) loops that span different units of time (e.g. match-to-match, season duration, off-season duration) where sets of risk factors can alter/adapt within and between units of time (Figure 1).52,65 As such, multiple interacting risk factors form a complex “web of determinants” that shift the probability for injury up-and-down across time.46,51,52,65,70 Given probability theory57,58 and complex systems theory,52,68–71 injury prevention screening is not contextual to predicting which specific player will get injured.46,50 Injury prevention screening is instead contextual to identifying athletes with combinations (patterns) of risk factors that contribute to an increased probability for injury.46,50 For the sports physical therapist, noncontact knee ligament injury prevention screening should aim to identify patterns of modifiable intrinsic risk factors (multifactorial ‘risk profile’52) for one point-in-time. Screening is then repeated (serial screening) at appropriate timepoints across a season/year to reveal changes in a player’s risk profile.50

Systems Science

Systems science refers to viewing a clinical problem-space as a system of interconnected, interacting components.54,69,72 Systems science is a foundation for complex systems theory which, in turn, informs the design of complex clinical interventions.73 A fundamental principle in systems science is the use of different types of research to develop clinical interventions.54,69,72 In sports physical therapy, an example of a systems science approach to problem-solving is using different levels of evidence42 (e.g. prospective research + cross-sectional research + individual opinion) in clinical reasoning processes. The integration of different types of research in a clinician’s reasoning yields a richer understanding of a problem-space than when one kind of research is considered alone.54,69,72 In this commentary, descriptive58 (injury mechanisms) and analytic-observational58 (cross-sectional, prospective) in vivo and in vitro human research studies are combined with basic kinesiological modelling to develop rational screening procedures contributing to noncontact knee ligament injury prevention in netball (Figure 2).

60347 Figure 2: Example steps, types of research, and levels of evidence used to devise clinically-reasoned, netball-specific, noncontact knee ligament injury prevention screening tests

Mechanism of Noncontact Knee Ligament Injury in Netball

Knowledge of the mechanism of knee injury gives insight into a player’s movement patterns at the instant-of-injury and the anatomical structures that are damaged. This knowledge contributes to step two of the sequence of prevention.49 Descriptive studies report small proportions (4.5-18.7%) of netball injuries occur during sudden stops when running or cutting to change direction21,25,27 with larger proportions (27.0-73.8%) occurring during landings.20,21,23,25 Other descriptive work reports 38-50% of knee injuries,25,26 81.3% of ACL injuries,27 and 100% of medial collateral ligament (MCL) injuries25 occurred during landings. Specifically, of all landing ACL injuries, 53.8% occurred during SLLs and 46.2% occurred during DLLs.27 Of all netball knee injuries, 24-29% followed contact with another player,20,21,23 although such injuries were not subdivided into direct or indirect contact74 (Table 1). One group performed detailed video analyses of netball ACL injuries and reported 50% followed indirect contact when airborne and contesting for the ball and 50% were noncontact when landing from receiving a mid-air pass.27 Together, descriptive studies indicate the majority of netball knee injuries are noncontact.20,21,23,25–27

Concerning whole-body kinematics when landing, support-leg trunk ipsilateral lateral flexion coupled with knee abduction was observed in 83.3% of netball noncontact ACL injuries.27 Frontal plane trunk motion relative to the knee is of interest because it can increase support-leg knee abduction forces.75 Because whole-body kinematics occur over a support-leg (i.e. weight-bearing leg), knee abduction motions are coupled with hip adduction and internal rotation (IR), knee flexion and IR, and foot pronation.27,76 The coupled trunk, hip, knee, and foot motions are termed a “valgus collapse”76 where knee valgus is synonymous with knee abduction. Concerning local knee joint kinematics, human cadaver (in vitro) research is useful for gaining insight into how joint kinematics influence ligament loads. Anterior tibial displacement (ATD), abduction, and IR generate ACL load/stress and elongation/strain.77–79 When such uniplanar motions are superimposed on each other to elicit a combined motion pattern of ATD + abduction + IR, ACL stress and strain increase exponentially.77–79 Because of the abduction component, the pattern also generates MCL stress and strain.79,80 Knee multiplanar combined motions such as those just described have been observed in 83.3% of netball noncontact knee injuries.27 When the mechanism of noncontact knee ligament injury is understood, the sports physical therapist can devise injury prevention screening procedures that identify which players may be predisposed to landings with kinematic patterns linked to injury-inducing events.

Biomechanics of Netball Landings and High-Risk Events

After knowledge of the mechanism of noncontact knee ligament injury is gained from descriptive studies, cross-sectional laboratory-based studies are employed to acquire a deeper understanding of the biomechanics of athletic tasks linked to the injury-inducing events (Figure 2). Specifically, laboratory-based studies are useful for developing a detailed kinetic and kinematic profile of athletic tasks associated with the mechanism of noncontact knee ligament injury. This profile then facilitates a deeper understanding of why such athletic tasks are ‘high-risk’ events that contain the potential for injury and further contributes to step two of the sequence of prevention.49 Because the majority of knee injuries occur during landings,25–27 focus will now be on the kinetics and kinematics of netball landings as high-risk events using variables popular in the netball literature.

The peak VGRF is of interest because it represents a foot-ground impact force that contributes to compression/shear/rotation forces experienced by the knee joint.18,19 For DLLs after catching a pass, VGRFs were 5.7BW.16 For SLLs with and without catching a pass, VGRFs were 3.5-5.7BW16,17 and 3.4BW,81 respectively. The time-to-peak VGRF (TTPVGRF) is of interest because short TTPVGRFs correspond to higher rate-of-loading of skeletal tissues82 and a significant challenge for the neuromuscular system relative to attenuating potentially harmful forces away from bone/cartilage/ligament tissue.82,83 In DLLs after catching a pass, TTPVGRFs were 48.8ms.16 In SLLs with and without catching a pass, TTPVGRFs were 30.6-42.1ms16,17 and 43.7ms, 81 respectively.

The peak braking force (BF) refers to horizontal ground reaction forces (HGRFs) which push players posteriorly when landing with anteriorly-directed momentum.84 The BF is of interest for the same reason as the VGRF and because it provides additional insight into potentially harmful tissue loading factors.17,82,85 For DLLs after catching a pass, BFs were 1.7BW.16 For SLLs after catching a pass, BFs were 1.4-3.3BW.16,17 The time-to-peak BF (TTPBF) is of interest for the same reason as the TTPVGRF. In DLLs after catching a pass, TTPBFs were 44.3ms.16 In SLLs after catching a pass, TTPBFs were 23.9-44.7ms.16,17

External and internal moments come from outside (e.g. VGRF) and inside (e.g. muscles) the body, respectively, and tend to cause joint rotation.18,19 Peak external moments are of interest because they estimate the tensile forces experienced by ligaments.19,86 In biomechanical modelling, external and internal moments balance each other and are equal and opposite in direction.18,19 Studies which only report knee internal moments of a specific size can, therefore, assume the knee experienced external moments of the same magnitude. For DLLs without catching a pass, knee internal adduction moments (opposing knee external abduction moments) were 0.38Nm/kg.87 For SLLs after catching a pass, knee internal adduction moments (opposing knee external abduction moments) were near 0.40Nm/kg.85

Frontal plane peak knee abduction angles are of interest because higher angles result in higher ACL and MCL stress/strain.77–80 As ligament strain increases with higher abduction angles, the point of ligament damage gets closer.88 For DLLs with and without catching a pass, knee abduction angles were 8.6°89 and 12.1°,87 respectively. For SLLs after catching a pass, knee abduction angles were 5.2°.89

Sagittal plane lower-limb joint displacement is of interest because small displacements are linked to ‘stiff’ landings and large displacements are linked to ‘soft’ landings.90–92 As for short TTPVGRFs, stiff landings are associated with higher tissue peak loads and rate-of-loading than soft landings.90,91,93 In DLLs without catching a pass, knee flexion at initial contact (IC) was 21.1° and at peak flexion was 85.2°, giving a mean displacement of 64.1°.87 In SLLs after catching a pass, knee flexion at IC was near 15° and at 50% of stance phase was near 60°.85 In other SLLs after catching a pass, knee flexion at IC was 16.3° and at peak flexion was 60.3°, giving a mean displacement of 44.1°.89

When the kinetic and kinematic profile of netball landings is familiar, ‘high-risk’ events that contain the potential for excessive loading of knee ligaments and injury can be better identified and understood. Decreased lower-limb flexion displacement during landing is related to increased VGRFs,94–96 increased knee abduction moments,94,96 and increased ACL tensile loads.93 Increased VGRFs are related to increased knee anterior shear forces.97,98 Increased knee external abduction moments are related to increased ACL and MCL loads.77–79 Higher rates-of-loading of the knee ligaments are more likely to cause tissue failure than lower rates-of-loading.99,100 Thus, netball DLLs and SLLs contain high-risk biomechanical features that contain the potential for noncontact ACL and MCL injury.

Developing Noncontact Knee Ligament Injury Prevention Screening Procedures

Having combined real-world observation of noncontact knee injury mechanisms (descriptive research) with laboratory-based study of landing tasks that simulate high-risk events (cross-sectional research), specific screening procedures can be considered relative to selected biomechanical features that contain the potential for noncontact knee ligament injury (Figure 2). The injury-inducing events and high-risk tasks discussed above require sophisticated equipment (e.g. 3D motion analysis) to determine kinetic/kinematic features (e.g. external abduction moment). Because such equipment is not typically available to community-based sports physical therapists, clinic-based ‘surrogate’ procedures related to 3D kinetic/kinematic features are required. Surrogate procedures are chosen using cross-sectional studies employing correlation or simple linear regression designs (Figure 2). Prospective studies reporting associations between intrinsic risk factors and future injury are also used to identify potential screening procedures (Figure 2). Alongside cross-sectional and prospective research, clinicians’ opinions (i.e. critical thinking101 + clinical reasoning102) derived using basic kinesiological modelling103,104 (e.g. identifying which muscles control joint motions in specific directions) can be additionally employed (Figure 2). Integrating different types of research (descriptive + cross-sectional + prospective + opinion) results in rich overall decision-making.54,69,72 Because little netball correlation, simple linear regression, or prospective research has been performed, the design of netball-specific knee ligament injury prevention screening draws from other related studies.

The Beighton score includes joint assessments to identify individuals with general joint hypermobility (GJH),105,106 which is prevalent in child107 and adult108,109 netball players. No published work has examined relationships between Beighton scores and knee biomechanical characteristics derived from 3D motion analysis of DLL/SLL tasks. In contrast, GJH is prospectively linked to an increased risk of all knee injuries110 and noncontact ACL injuries111 in athletic females. General joint hypermobility assessment using the Beighton score procedures may be useful for identifying players predisposed to increased risk for noncontact knee ligament injury.

The ankle is an important component in the lower-limb kinetic chain.112 In DLLs, decreased straight-knee ankle dorsiflexion (DF) ROM measured with a goniometer was related to increased VGRFs, knee external abduction moments, and knee abduction displacements.113,114 In DLLs, decreased bent-knee ankle dorsiflexion ROM measured with the weight-bearing lunge test (WBLT) was related to decreased knee flexion displacements.115 No prospective work has reported an association between ankle dorsiflexion ROM and noncontact knee ligament injury. Screening ankle DF ROM with a goniometer or the WBLT may provide data for identifying players predisposed to sub-optimal landing biomechanics.

The lateral trunk muscles influence pelvis position and motion104,116 and pelvis position and motion influence knee biomechanics.104,117 In SLLs, decreased trunk rotation strength measured with an isokinetic dynamometer (IKD) was related to increased knee abduction displacement.118 In a single-leg squat (SLS), decreased isometric side-bridge strength measured with a handheld dynamometer (HHD)119 and decreased strength-endurance measured via holding-time120 were related to increased knee abduction angles. In prospective work, large trunk lateral flexion displacements following laterally-directed perturbations were linked to higher odds for experiencing noncontact ACL injury.121 Screening lateral trunk muscle performance with a HHD or isometric holding-times may have utility for identifying players predisposed to sub-optimal landing biomechanics and risk for noncontact knee ligament injury.

Lower-limb muscles generate internal moments that absorb foot-ground impact forces19 and stress-shield skeletal tissues from excessive loads.122 Outside 3D motion analysis, lower-limb internal moment generating ability is inferred using strength tests.123 For SLLs, decreased isometric hip abduction strength measured with a HHD was related to increased knee abduction angles.124 For SLLs, decreased isometric hip external rotation (ER) strength measured with a HHD was related to increased VGRFs, knee external abduction moments, knee abduction angles, and knee anterior shear forces,86,124 and decreased isometric knee ER strength measured with an IKD was related to increased knee IR angles.125 For SLLs, decreased SLS strength measured with a barbell and decreased isometric knee flexion strength measured with an IKD were related to increased knee abduction and IR angles.126 In prospective research, decreased lower-limb strength estimated with one-repetition-maximum (1RM) barbell back-squats was associated with increased odds for traumatic knee injuries.127 In other prospective and case-control work, decreased isometric hip abduction and ER strength estimated with a HHD128 and decreased knee flexion strength estimated with an IKD129 were associated with noncontact ACL injuries. Screening hip and knee muscle strength with double- and single-leg strength tests may be useful for identifying players predisposed to sub-optimal landing biomechanics and risk for noncontact knee ligament injury. Considering kinesiological modelling, given that the quadriceps and gastrocnemius/soleus control knee flexion and ankle DF, respectively,103,104 and the dissipation of landing impact forces,92 screening of knee extensor130 and ankle plantarflexor131,132 muscle strength is wise. Isokinetic dynamometers and HHDs can be expensive and not easily available to community-based practitioners.130 Alternatively, leg press, knee flexion, and knee extension resistance machines can be more readily accessible.130 Single-leg 1RM strength tests can be performed with netball players in local communities and contribute to knee injury prevention procedures.130,133 Combining free-weight and resistance machine procedures for double-/single-leg strength testing may be the most thorough approach.66

Balance is the process of maintaining the body’s center-of-mass and center-of-pressure within its base-of-support via internal moments countering external moments that act to destabilize the body and its joints.134 Balance is a sensorimotor process involving proprioceptive, visual, and vestibular sensory information used by the central nervous system to adjust motor output and maintain postural equilibrium.134 For SLLs, increased single-leg stance center-of-pressure excursion (worse balance) was related to increased knee external abduction moments.135 In prospective studies, reduced dynamic balance defined by three (anterior/posteromedial/posterolateral) of the six directions in the Star Excursion Balance Test (SEBT) was associated with increased odds of lower-limb injuries including knee sprains.136 The SEBT has since been modified to use just the anterior, posteromedial, and posterolateral directions in the form of the Y-Balance Test (YBT).137 Reduced YBT performance defined by a reduced anterior/posteromedial/posterolateral composite score138 and a reduced anterior score alone139 have been prospectively linked to lower-limb noncontact injuries. Reduced static balance defined by a computer-force plate system has been associated with increased ACL injury frequency.140 Screening single-leg balance (SLB) with procedures such as the SEBT, YBT, and timed eyes-open/eyes-closed balance may provide data for identifying players predisposed to sub-optimal landing biomechanics and risk for noncontact knee ligament injury. Timed eyes-closed SLB tests have been used in preseason screening for community-level netball players.25,141

Neurocognitive performance refers to cerebral neural functions contributing to cognition and includes processes such as visual attention, visual memory, verbal memory, processing speed, reaction time, and dual-tasking.142,143 Neurocognitive performance is integrated with sensorimotor functions (proprioception, neuromuscular control) to activate skeletal muscle and maintain joint stability during athletic tasks.142 No published work has examined relationships between measures of neurocognitive performance and knee biomechanical characteristics derived from 3D motion analysis of DLL/SLL tasks. One study, however, reported that decreased neurocognitive performance (decreased visual memory) was associated with increased knee abduction angles during sidestep cutting.144 Preseason neurocognitive assessment using the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) procedures145–147 was linked to in-season lower-limb sprains148 and noncontact ACL injuries.149 Screening neurocognitive performance with the ImPACT procedures or other computerized systems may have utility for identifying players predisposed to sub-optimal knee biomechanics and risk for noncontact knee ligament injury.

Movement screening is the process of assessing athletes’ kinematic patterns relative to the biomechanics of injury mechanisms and high-risk events that contain the potential for noncontact knee ligament injury. Because 3D motion analysis equipment is not easily accessible to community-based practitioners, 2D motion analysis procedures have been developed using commonly available high-definition video cameras. During landings, 2D measurements of frontal plane knee kinematics (e.g. knee abduction angle) are not related to 3D measurements.150–152 During a SLS, however, 2D measurements of frontal plane knee kinematics are related to 3D measurements.150,153,154 Therefore, 2D motion analysis is not advocated for assessing DLL/SLL frontal plane knee kinematics.150–152 Conversely, use of a SLS in netball knee injury prevention screening is advocated because its knee biomechanical characteristics are related to those in netball-specific leap-landings.155 If high-definition video cameras are not accessible, generic observational DLL (e.g. Landing Error Scoring System [LESS]-Real Time [LESS-RT],156 Tuck Jump Assessment [TJA]157), SLL (e.g. Qualitative Analysis of Single-Leg Loading158), and SLS158,159 movement screens have been developed where the observer visually scores the athlete’s hip-knee-ankle kinematics according to pre-defined criteria. Generic DLL movement screens such as the LESS and TJA are not related to the biomechanics of netball-specific SLLs.160 One group reported the reliability of the ‘Netball Movement Screening Tool’ (NMST) which contains 10 tasks deemed relevant to assessing netball knee injury risk.161 The NMST has not been used further beyond another group who employed the NMST to evaluate outcomes from a performance training program.162 For prospective work, increased trunk ipsilateral lateral flexion and knee abduction measured with 2D motion analysis during a SLL were associated with increased frequency of noncontact knee soft tissue injury.163 Increased “dynamic knee valgus” measured with 2D motion analysis during a SLL was evident in female athletes who later experienced a noncontact ACL injury compared to those who did not.164 Poor (higher) LESS scores have been prospectively associated with increased frequency of noncontact ACL injury.165 Screening whole-body and knee kinematics patterns with procedures such as 2D motion analysis and observational movement screens may be useful for identifying netball players predisposed to sub-optimal landing biomechanics and risk for noncontact knee ligament injury.

The lower-limb functional performance test (FPT) includes hop, leap, jump, linear-sprint, change-of-direction, and agility tasks.166 In knee injury prevention, single-leg FPTs are recommended to isolate each lower-limb and expose unilateral deficits that can remain hidden in double-leg tasks.166 In netball, SLL versus DLL occurs on 58.5-67.1% of occasions14,167 and, therefore, single-leg FPTs are important components of netball-specific knee injury prevention screening. Single-leg FPTs (e.g. hop, leap) recreate the joint compression/shear/torsion/rotation forces encountered in sport-specific activity166,168,169 and are measured using performance-related variables such as distance (centimeters) or time (seconds).166,170,171 No study has examined the association between single-leg FPT performance-related variables and knee biomechanical characteristics derived from 3D motion analysis of DLL/SLL tasks. For prospective research, athletes with a single-hop-for-distance mean distance of ≤64% of height for either limb were at increased risk of thigh and knee injuries172 and athletes with a side-to-side difference (asymmetry) of >10% for the single-hop-for-distance experienced more frequent noncontact ankle and foot trauma.173 Screening single-leg FPTs may provide data for identifying netball players predisposed to increased risk of noncontact knee ligament injury. Further considerations include that some FPTs may be more suited to assessing lower-limb force production (e.g. vertical-hop) versus force absorption (e.g. horizontal-hop) ability.166,174 The shared variance between vertical-hop and horizontal-hop performance in netball players is low and, therefore, such tests capture different aspects of lower-limb motor-performance.174 Unidirectional (e.g. triple-hop-for-distance)171 and multidirectional (e.g. zig-zag hop)170,171 repeated hop single-leg FPTs may also be useful for adding greater repeated impact and frontal and transverse plane challenges to the knee joint.166,170 Recently, screening of a community-level adult netball team using single-leg FPTs revealed that side-to-side asymmetries of >10% for the triple-hop-for-distance, single-hop-for-distance, and vertical-hop existed for 8.7%, 8.7%, and 52.2% of players, respectively.141 Given such considerations, netball knee injury prevention screening may require a selection of different single-leg hop FPTs.

DISCUSSION: CLINICAL INTEGRATION AND APPLICATION

Based on the different types of research cited in the previous section, suggested noncontact knee ligament injury intrinsic risk factor screening procedures appear in Table 3. In terms of integrating and applying such procedures in sports physical therapy practice in netball, it may not be necessary to perform all tests in Table 3. Clinicians can decide for themselves which procedures are viable based on their local logistical constraints (e.g. equipment/personnel/finance/time availability).66 When a battery of procedures has been assembled, and given the recursive nature of netball training and competition, serial screening should occur at appropriate timepoints across a season/year to reveal changes in a player’s risk profile.50,52,65,66

The majority of screening procedures in Table 3 are for modifiable intrinsic risk factors for which conservative interventions are applicable. One intrinsic risk factor, the Beighton score for GJH,105,106 is nonmodifiable. The value of including such a nonmodifiable risk factor is that further supplementary sensorimotor control interventions for enhancing knee functional joint stability can be considered for those classed as having GJH.175

60349 Table 3: Suggested netball-specific noncontact knee ligament injury prevention screening tests*†

Characteristic	Test	Example Variable	Related Study Reference number	
 	 	 	 	
General joint hypermobility	Beighton score	Composite score‡	105	
 	 	 	 	
Ankle joint DF mobility	Straight-knee passive DF ROM with	°	113, 114	
 	a goniometer	 	 	
 	 	 	 	
 	Weightbearing lunge test	cm	115	
 	 	 	 	
Trunk muscle strength	Side-bridge isometric strength with	%BW	119	
 	a HHD	 	 	
 	 	 	 	
 	Side-bridge isometric hold	s	120	
 	 	 	 	
Lower-limb muscle	1RM modified barbell single-leg squat	%BW, LSI, A-A	126	
strength	 	 	 	
 	1RM single-leg leg-press	%BW, LSI, A-A	130	
 	 	 	 	
Hip muscle strength	Side-lying straight-leg hip abduction	%BW, LSI, A-A	124	
 	isometric strength with a HHD	 	 	
 	 	 	 	
 	Prone bent-knee hip ER isometric	%BW, LSI, A-A	124	
 	strength with a HHD	 	 	
 	 	 	 	
Knee muscle strength	1RM single-leg knee extension	%BW, LSI, A-A	130	
 	 	 	 	
 	1RM single-leg knee flexion	%BW, LSI, A-A	130	
 	 	 	 	
Ankle muscle strength	1RM standing single-leg straight-leg	%BW, LSI, A-A	131	
 	calf-raise	 	 	
 	 	 	 	
 	1RM seated single-leg bent-leg	%BW, LSI, A-A	132	
 	calf-raise	 	 	
 	 	 	 	
Balance	Star Excursion Balance Test	%LL, LSI, A-A	136	
 	Anterior/posteromedial/posterolateral	 	 	
 	 	 	 	
 	Y-Balance Test	Composite score‡	138	
 	 	cm, A-A	139	
 	 	 	 	
 	Eyes-closed single-leg balance	s, LSI, A-A	25, 141	
 	 	 	 	
Neurocognitive performance	ImPACT	Composite score‡	146, 147	
 	 	 	 	
Lower-limb movement	2D high-definition video single-leg	Peak ipsilateral	163, 164	
patterns	drop-vertical-jump	trunk lean angle, °	 	
 	 	Peak knee	 	
 	 	abduction angle, °	 	
 	 	 	 	
 	2D high-definition video single-leg	Peak ipsilateral	150	
 	squat	trunk lean angle, °	 	
 	 	Peak knee	 	
 	 	abduction angle, °	 	
 	 	 	 	
 	LESS-RT	Composite score‡	156	
 	 	 	 	
 	QASLL	Composite score‡	158	
 	 	 	 	
Lower-limb functional	Single-hop-for-distance	%LL, %H, LSI, A-A	141, 171	
performance	 	 	 	
 	Triple-hop-for-distance	%LL, %H, LSI, A-A	141, 171	
 	 	 	 	
 	Adapted crossover hop for distance	%LL, %H, LSI, A-A	170	
 	 	 	 	
 	Vertical-hop	%LL, %H, LSI, A-A	141	
 	 	 	 	
* Modified from reference 66.

† All single-leg tests are performed for both right and left sides.

‡ = see Related Study citation for scoring system.

DF = dorsiflexion; ROM = range-of-motion; ° = degrees; cm = centimeters; HHD = handheld dynamometer;

%BW = percentage of bodyweight = (weight lifted (kg) ÷ bodyweight (kg)) × 100; s = seconds;

1RM = one repetition maximum; LSI = limb symmetry index (%) = (right side score ÷ left side score) × 100;

A-A = absolute-asymmetry = LSI of 100% − player’s actual LSI (with ‘+’ or ‘−’ sign then removed);

ER = external rotation; %LL = percentage of leg-length = (distance hopped (cm) ÷ leg-length (cm)) × 100;

ImPACT = Immediate Post-Concussion Assessment and Cognitive Testing; 2D = two dimensional;

LESS-RT = Landing Error Scoring System-Real Time; QASLL = Qualitative Analysis of Single-Leg Loading;

FPT = functional performance test;

%H = percentage of standing height = (distance hopped (cm) ÷ standing height (cm)) × 100.

When a battery of screening procedures has been administered, the sports physical therapist should design a targeted intervention program to address intrinsic risk factors that are of specific concern (e.g. hip abductor muscle strength, balance, reaction time).50,141,176–179 These interventions then contribute to stage three of the sequence of prevention.49 During stage three and across the competitive season, noncontact knee ligament injury incidence requires monitoring. At the end of the season, noncontact knee ligament injury incidence is compared to that of previous seasons; this represents stage four of the sequence of prevention49 and is a critical evaluative step in any primary prevention strategy for injury.44–46,48,49 Future research should endeavour to identify modifiable intrinsic risk factors for noncontact knee ligament injury specifically in netball. Research should be performed for all levels of the game and all competitive age groups.

SUMMARY

Netball is a team court-sport played worldwide and becoming more popular in the US. Noncontact knee ligament injuries are common due to a knee abduction collapse during landing. High-risk landing events that contain the biomechanical potential for noncontact knee ligament injury are common in netball. Cross-sectional research, prospective research, and kinesiological modelling provide insight into modifiable intrinsic risk factors linked to high-risk landing biomechanics and actual noncontact knee ligament injury incidence. This clinical commentary has described how theoretical principles (injury control, sequence of prevention, principles of screening in injury prevention, multifactorial model of injury etiology, complex systems theory, systems science), different types of research (descriptive, analytic-observational), and different levels of evidence (prospective, cross-sectional, clinician’s opinion) underpin a rational clinical reasoning process that develops screening procedures for community-level netball noncontact knee ligament injury prevention. An example of how such theories, research, and evidence can be applied by the sports physical therapist has been provided in the form of detailed explanations for suggested screening procedures (Figure 2, Table 3) and comments on the need for repeated screening at strategic timepoints across a season/year.

Conflict of Interest Statement

The author declares there are no conflicts of interest.
==== Refs
Regions and Members International Netball Federation 2020
2020-6-24 https://netball.sport/inside-inf/regions-members
History of Netball International Netball Federation 2020
2020-6-24 https://netball.sport/game/history-of-netball
England Netball Annual Report 2016-2017 England Netball Leicestershire 2018

Active Lives Survey Sport England 2020
2020-6-24 https://www.sportengland.org/know-your-audience/data/active-lives
Annual Report 2018 Netball Australia Netball Australia Australia 2018

England Netball Annual Report 2016-2017 Netball England Leicestershire 2018

Netball Fact Sheet Netball America 2020
2020-6-24 https://netballamerica.com/communications/fact-sheet/
2nd World University Netball Championship International University Sports Federation 2020
2020-6-24 https://www.fisu.net/netball/2nd-wuc-netball
USA Team and USA Representative Teams Netball America 2020
2020-6-24 https://netballamerica.com/training-room/usa-team/
Active living and injury risk Int J Sports Med Parkkari Jari Kannus Pekka Natri A Lapinleimu I Palvanen Mika Heiskanen M Vuori I Jarvinen M 2004
25 3 209 216 0172-4622 15088246
Sociodemographic predictors of sport injury in adolescents Med Sci Sports Exerc Rose MS Emery CA Meeuwisse WH 2008
40 3 444 450 0195-9131 18379205
The association of sport specialization and training volume with injury history in youth athletes Am J Sports Med Posty EG Trigstedy SM Riekenayz JW Hetzel S McGuinez TA Brooksz MA Bell DR 2017
45 6 1405 1412 0363-5465 28288281
Rules of Netball International Netball Federation International Netball Federation England 2020

Landing patterns in netball: analysis of an international game Br J Sports Med Hopper D Lo SK Kirkham C Elliott B 1992
26 2 101 106 0306-3674 1623354
Lower limb injury risk in netball: a time-motion analysis investigation Journal of Human Movement Studies Williams R O'Donoghue PG 2005
49 5 315 331 0306-7297
Kinetic analysis of landings in netball: is a footwork rule change required to decrease ACL injuries? J Sci Med Sport Otago Leonie 2004
7 1 85 95 1440-2440 15139168
A kinetic analysis of footfall patterns at landing in netball Australian Journal of Science and Medicine in Sport Steele JR Lafortune MA 1989
21 1 10 13
Basic Biomechanics Hall S McGraw-Hill Higher Education New York 2014

Gait Analysis. Normal and Pathological Function Perry J Burnfield J SLACK Inc. New Jersey 2010

A survey of netball injuries and conditions related to these injuries Aust J Physio Hopper D 1986
32 4 231 239 0004-9514
Lower limb and back injury patterns of elite netball players Sports Med Hopper D Elliott Bruce 1993
16 2 148 162 8378669
Injury prevalence of netball players in South Africa: The need for injury prevention South African Journal of Physiotherapy Pillay Tanushree Frantz Jose M 2012
68 3 7 10
Injury surveillance of an Australian community netball club Phys Ther Sp Smith Melinda M Franettovich Mendis M Dilani Parker Alexander Grantham Brittany Stewart Simon Hides Julie 2020
44 41 46
Epidemiology of basketball and netball injuries that resulted in hospital admission in Australia, 2000–2004 Med J Aust Flood Louise Harrison James E 2009
190 2 87 90 0025-729X
Do selected kinanthropometric and performance variables predict injuries in female netball players J Sports Sci Hopper DM Hopper JL Elliott Bruce 1995
13 3 213 222 7563288
A descriptive epidemiology of netball injuries during competition: a five year study Br J Sports Med Hopper Diana Elliott Bruce Lalor Jenny 1995
29 4 223 228 0306-3674 8808533
Mechanisms of anterior cruciate ligament injuries in elite women's netball: a systematic video analysis J Sports Sci Stuelcken MC Mellifont DB Gorman AD Sayers MG 2016
34 16 1516 1522 1466-447X 26644060
The public health impact of injury during sport and active recreation J Sci Med Sport Finch Caroline Cassell Erin 2006
9 6 490 497 1440-2440 16616615
High incidence and costs for anterior cruciate ligament reconstructions performed in Australia from 2003–2004 to 2007–2008: time for an anterior cruciate ligament register by Scandinavian model? Scand J Med Sci Sports Janssen KW Orchard JW Driscoll TR van Mechelen W 2012
4 22 495 501 0905-7188
The role of insurance data in setting priorities for netball injury prevention strategies J Sci Med Sport Otago Leonie Peake Jacqui 2007
10 2 105 109 1440-2440 16844407
A 7‐year study on risks and costs of knee injuries in male and female youth participants in 12 sports Scand J Med Sci Sports Loes M de Dahlstedt Lars J Thomée Roland 2000
10 2 90 97 0905-7188 10755279
Cost-Effectiveness Analysis of the Most Common Orthopaedic Surgery Procedures: Knee Arthroscopy and Knee Anterior Cruciate Ligament Reconstruction Arthroscopy Lubowitz James H Appleby David 2011
27 10 1317 1322 21855268
Anterior cruciate ligament injury and reconstruction among university students Clin Orthop Relat Res Freedman KB Glasgow MT Glasgow SG Bernstein J 1998
356 208 212 0009-921X
The effects of timing of pediatric knee ligament surgery on short-term academic performance in school-aged athletes Am J Sports Med Trentacosta NE Vitale MA Ahmad CS 2009
37 9 1684 1691 1552-3365 19460815
Top 10 on the 10th – Injury Prevention England Netball 2016
2020-6-24 https://www.englandnetball.co.uk/coachblog/top-10-10th-injury-prevention/
What’s the rate of knee osteoarthritis 10 years after anterior cruciate ligament injury? An updated systematic review Br J Sports Med Lie Marthe Mehus Risberg May Arna Storheim Kjersti Engebretsen Lars Britt Elin Øiestad 2019
53 18 1162 1167 0306-3674 30936063
The long-term consequence of anterior cruciate ligament and meniscus injuries: Osteoarthritis Am J Sports Med Lohmander L Englund P Dahl Ludvig Roos Ewa 2007
35 10 1756 1769 17761605
Emotional response to sport concussion compared to ACL injury Brain Inj Mainwaring Lynda M Hutchison Michael Bisschop Sean M Comper Paul Richards Doug W 2010
24 4 589 597 1362-301X 20235761
Depression and psychiatric disease associated with outcomes after anterior cruciate ligament reconstruction World J Orthop Wu HH Liu M Dines JS Kelly JD Garcia GH 2016
7 11 709 717 2218-5836 27900267
Suicide in Athletes: A Review and Commentary Clin Sports Med Baum Antonia L 2005
24 4 853 869 0278-5919 16169450
Injured athletes and the risk of suicide J Athl Train Smith AM Milliner EK 1994
29 4 337 341 16558297
The levels of evidence and their role in evidence-based medicine Plastic Reconstr Surg Burns Patricia B Rohrich Rod J Chung Kevin C 2011
128 1 305 310
Accident prevention-injury control-injury prevention-or whatever? Inj Prev Avery JG 1995
1 1 10 9345985
Introduction: the scientific basis for injury control Epidemiol Rev Rivara FP 2003
25 20 23 0193-936X 12923987
Injury control: new challenges Pediatrics in Review Johnston Brian Duncan Rivara Frederick P 2003
24 4 111 118 0191-9601 12671097
Injury Prevention: An International Perspective Barss P Smith G Baker S Mohan D Oxford University Press New York 1998

Context matters: revisiting the first step of the 'sequence of prevention' of sports injuries Sports Med Bolling Caroline van Mechelen Willem Pasman H Roeline Verhagen Evert 2018
48 10 2227 2234 29956077
A new framework for research leading to sports injury prevention J Sci Med Sport Finch Caroline 2006
9 1 3 9 1440-2440 16616614
Incidence, severity, etiology and prevention of sports injuries: A review of concepts Sports Med van Mechelen Willem Hlobil Hynek Kemper Han 1992
14 2 82 99 0112-1642 1509229
Do not throw the baby out with the bathwater; screening can identify meaningful risk factors for sports injuries Br J Sports Med Verhagen Evert van Dyk Nicol Clark Nicholas Shrier Ian 2018
52 19 1223 1224 0306-3674 29643091
Assessing causation in sport injury: A multifactorial model Clin J Sport Med Meeuwisse Willem 1994
4 3 166 170
Complex systems approach for sports injuries: Moving from risk factor identification to injury pattern recognition - narrative review and new concept Br J Sports Med Bittencourt NF Meeuwisse W Mendonça L Nettel-Aguirre A Ocarino J Fonseca S 2016
50 21 1309 1314 0306-3674 27445362
Translational research: understanding the continuum from bench to bedside Transl Res Drolet Brian C Lorenzi Nancy M 2011
157 1 1 5 1931-5244 21146144
Interdisciplinarity and systems science to improve population health: a view from the NIH Office of Behavioral and Social Sciences Research Am J Prev Med Mabry Patricia L Olster Deborah H Morgan Glen D Abrams David B 2008
35 2 S211 S224 0749-3797 18619402
Injury prevention and control in children Ann Emerg Med Mace Sharon E Gerardi Michael J Dietrich Ann M Knazik Stephen R Mulligan-Smith Deborah Sweeney Robert L Warden Craig R 2001
4 38 405 414 0196-0644
The influence of extrinsic and intrinsic risk factors on the probability of sustaining an injury Accid Anal Prev McLeod R Stockwell T Rooney R Stevens M Phillips M Jelinek G 2003
35 1 71 80 0001-4575 12479898
Probability, clinical decision making and hypothesis testing Ind Psychiatry J Banerjee A Jadhav SL Bhawalkar JS 2009
18 1 64 69 0972-6748 21234167
Foundations of Clinical Research: Applications to Practice Portney LG Watkins MP Pearson/Prentice Hall New Jersey 2009
0131716409
Science and rights: The 'clinical reasoning' within health needs assessment GSTF Journal of Law and Social Sciences Di Costanzo Caterina 2012
1 2 84 89 2251-2853
Oxford English Dictionary Waite M Oxford University Press Oxford 2012

Intrinsic risk factors for exercise-related lower limb injuries Sports Med Neely FG 1998
26 4 253 263 0112-1642 9820924
Risk factors for injury in child and adolescent sport: A systematic review of the literature Clin J Sport Med Emery Carolyn A 2003
13 4 256 268 12855930
Modern Epidemiology Rothman K Greenland S Lash T Lippincott Williams and Wilkins Philadelphia 2008

A Dictionary of Epidemiology Porta M Oxford University Press Oxford 2014

A dynamic model of etiology in sport injury: the recursive nature of risk and causation Clin J Sport Med Meeuwisse Willem H Tyreman Hugh Hagel Brent Emery Carolyn 2007
17 3 215 219 1050-642X 17513916
Noncontact knee soft-tissue injury prevention considerations and practical applications for netball players Strength and Conditioning Journal Mullally EM Clark NC 2020
In press 10.1519/SSC.0000000000000609
Understanding injury mechanisms: a key component of preventing injuries in sport Br J Sports Med Bahr R Krosshaug T 2005
39 6 324 329 15911600
Beyond reductionism Science Gallagher Richard Appenzeller Tim Normile Dennis 1999
284 5411 79 0036-8075
A call to address complexity in prevention science research Prev Sci Lich KH Ginexi EM Osgood ND Mabry PL 2013
14 3 279 289 1573-6695 22983746
Nonlinearity in the epidemiology of complex health and disease processes Theor Med Bioeth Philippe P Mansi O 1998
19 6 591 607 1386-7415 10051792
Complexity, simplicity, and epidemiology Int J Epidemiol Pearce Neil Merletti Franco 2006
35 515 519 16415326
Systems science: A revolution in public health policy research Am J Public Health Mabry Patricia L Marcus Stephen E Clark Pamela I Leischow Scott J M'Endez David 2010
100 7 1161 1163 0090-0036 20530757
Complex interventions or complex systems? Implications for health economic evaluation BMJ Shiell Alan Hawe Penelope Gold Lisa 2008
336 7656 1281 1283 18535071
Incidence of ACL injury Understanding and Preventing Noncontact ACL Injuries Marshall S Padua D McGrath M Hewett T Shultz S Griffin L Human Kinetics Illinois 2007
5 29
Whole body kinematics and knee moments that occur during an overhead catch and landing task in sport Clin Biomech Dempsey AR Elliott BC Munro BJ Steele JR Lloyd DG 2012
27 5 466 474 1879-1271
Mechanisms of anterior cruciate ligament injury in basketball: video analysis of 39 cases Am J Sports Med Krosshaug T. Nakamae A. Boden BP Engebretsen L. Smith G. Slauterbeck JR Hewett TE Bahr R. 2007
35 3 359 367 0363-5465 17092928
Combined knee loading states that generate high anterior cruciate ligament forces J Orthop Res Markolf KL Burchfield DM Shapiro MM Shepard MF Finerman GA Slauterbeck JL 1995
13 6 930 935 0736-0266 8544031
Valgus plus internal rotation moments increase anterior cruciate ligament strain more than either alone Med Sci Sports Exerc Shin CS Chaudhari AM Andriacchi TP 2011
43 8 1484 1491 1530-0315 21266934
The effect of isolated valgus moments on ACL strain during single-leg landing: A simulation study J Biomech Shin C.S. Chaudhari A.M. Andriacchi T.P. 2009
42 3 280 285 19100550
Strain in the human medial collateral ligament during valgus loading of the knee Clin Orthop Relat Res Gardiner JC Weiss JA Rosenberg TD 2001
391 266 274 0009-921X 11603680
Landing in netball: effects of taping and bracing the ankle Br J Sports Med Hopper DM McNair P Elliott BC 1999
33 6 409 413 10597851
Biomechanical factors affecting performance in netball. Implications for improving performance and injury reduction Sports Med Steele JR 1990
10 2 88 102 0112-1642 2204101
Biomechanics of Musculoskeletal Injury Whiting WC Zernicke RF Human Kinetics Illinois 2008

Dancers with patellar tendinopathy exhibit higher vertical and braking ground reaction forces during landing J Sports Sci Fietzer AL Chang YJ Kulig K 2012
30 11 1157 1163 1466-447X 22758398
Knee loading patterns in a simulated netball landing task Eur J Sport Sci Stuelcken M Greene A Smith R Vanwanseele B 2013
13 5 475 482 1536-7290 24050464
Influences of hip external rotation strength on knee mechanics during single-leg drop landings in females Clin Biomech Lawrence RK Kernozek TW Miller EJ Torry MR Reuteman P 2008
23 6 806 813 0268-0033
Effects of prophylactic knee bracing on knee joint kinetics and kinematics during netball specific movements Phys Ther Sp Sinclair JK Vincent H Richards JD 2017
23 93 98 1873-1600
Biomechanics of knee ligaments: injury, healing, and repair J Biomech Woo SL Abramowitch SD Kilger R Liang R 2006
39 1 1 20 0021-9290 16271583
Effects of prophylactic knee bracing on knee joint kinetics and kinematics during single-and double-limb post-catch deceleration strategies in university netballers Sport Sci Health Sinclair Jonathan Taylor Paul John Foxcroft Hannah 2019
15 1 215 222
Effect of landing stiffness on joint kinetics and energetics in the lower extremity Med Sci Sports Exerc Devita P Skelly WA 1992
24 1 108 115 0195-9131 1548984
Ankle biomechanics during four landing techniques Med Sci Sports Exerc Self BP Paine D 2001
33 8 1338 1344 0195-9131 11474336
Contributions of lower extremity joints to energy dissipation during landings Med Sci Sports Exerc Zhang SN Bates BT Dufek JS 2000
32 4 812 819 0195-9131 10776901
The effects of single-leg landing technique on ACL loading J Biomech Laughlin WA Weinhandl JT Kernozek TW Cobb SC Keenan KG O'Connor KM 2011
44 10 1845 1851 1873-2380 21561623
Gender, vertical height and horizontal distance effects on single-leg landing kinematics: Implications for risk of non-contact ACL injury J Hum Kinet Ali Nicholas Rouhi Gholamreza Robertson Gordon 2013
37 27 38 24146702
Stiff landings are associated with increased ACL injury risk in young female basketball and floorball players Am J Sports Med Leppänen M Pasanen K Kujala UM Vasankari T Kannus P Äyrämö S Krosshaug T Bahr R Avela J Perttunen J 2017
45 2 386 393 0363-5465 27637264
Limited hip and knee flexion during landing is associated with increased frontal plane knee motion and moments Clin Biomech Pollard Christine D Sigward Susan M Powers Christopher M 2010
25 2 142 146 0268-0033
Predictors of proximal tibia anterior shear force during a vertical stop‐jump J Orthop Res Sell Timothy C Ferris Cheryl M Abt John P Tsai Yung‐Shen Myers Joseph B Fu Freddie H Lephart Scott M 2007
25 12 1589 1597 0736-0266 17626264
Lower extremity biomechanics during the landing of a stop-jump task Clin Biomech Yu B Lin CF Garrett WE 2006
21 3 297 305 0268-0033
Biomechanics of anterior cruciate ligament failure: an analysis of strain-rate sensitivity and mechanisms of failure in primates J Bone Joint Surg Am Noyes FR DeLucas JL Torvik PJ 1974
56 2 236 253 0021-9355 4452684
The strength and failure characteristics of rat medial collateral ligaments J Trauma Crowninshield RD Pope MH 1976
16 2 99 105 0022-5282 1255835
Active learning strategies to promote critical thinking J Athl Train Walker Stacy E 2003
38 3 263 267 16558680
Clinical reasoning in physical therapy: a concept analysis Phys Ther Huhn Karen Gilliland Sarah J Black Lisa L Wainwright Susan F Christensen Nicole 2019
99 4 440 456 0031-9023 30496522
Manual of Structural Kinesiology Floyd RT McGraw-Hill Education New York 2015

Kinesiology of the Musculoskeletal System Neumann DA Mosby St Louis 2002

Articular mobility in an African population Ann Rheum Dis Beighton P Solomon L Soskolne CL 1973
32 5 413 418 0003-4967 4751776
Hypermobility Syndrome Keer R Grahame R Butterworth Heinemann Philadelphia 2003

Hypermobility and sports injuries in junior netball players Br J Sports Med Smith R Damodaran AK Swaminathan S Campbell R Barnsley L 2005
39 9 628 631 0306-3674 16118300
Relative joint contribution to joint hypermobility: The need for careful consideration of lumbar flexion Int J Sports Phys Ther Armstrong Ross 2018
13 4 676 686 2159-2896 30140561
The influence of joint hypermobility on functional movement control in an elite netball population: A preliminary cohort study Phys Ther Sp Soper Kessie Simmonds Jane V Kaz Hanadi Kaz Ninis Nelly 2015
16 2 127 134 1466-853X
Injury risk factors in female European football: a prospective study of 123 players during one season Scand J Med Sci Sports Östenberg Anna Roos H 2000
10 5 279 285 11001395
Risk factors associated with noncontact injury of the anterior cruciate ligament: a prospective four-year evaluation of 859 West Point cadets Am J Sports Med Uhorchak JM Scoville CR Williams GN Arciero RA St Pierre P Taylor DC 2003
31 6 831 842 0363-5465 14623646
Kinetic chain exercise in knee rehabilitation Sports Med Palmitier Randal A An Kai-Nan Scott Steven G Chao Edmond YS 1991
11 6 402 413 0112-1642 1925185
Ankle-dorsiflexion range of motion and landing biomechanics J Athl Train Fong Chun-Man Blackburn J Troy Norcross Marc F McGrath Melanie Padua Darin A 2011
46 1 5 11 1062-6050 21214345
The association of dorsiflexion flexibility on knee kinematics and kinetics during a drop vertical jump in healthy female athletes Knee Surg Sports Traumatol Arthrosc Malloy Philip Morgan Alexander Meinerz Carolyn Geiser Christopher Kipp Kristof 2015
23 12 3550 3555 0942-2056 25112598
Ankle dorsiflexion range of motion is associated with kinematic but not kinetic variables related to bilateral drop-landing performance at various drop heights Hum Mov Sci Howe Louis Bampouras Theodoros North Jamie Waldron Mark 2019
64 320 328 1872-7646 30836206
The Physiology of the Joints. Volume Three. The Trunk and Vertebral Column Kapandji IA Churchill Livingstone Edinburgh 1998

The influence of abnormal hip mechanics on knee injury: a biomechanical perspective J Orthop Sports Phys Ther Powers Christopher M 2010
40 2 42 51 0190-6011 20118526
The relationship among trunk strength, trunk power, and knee kinematics during a stop jump cut maneuver J Athl Train Keenan KA Varnell MS Sell TC Abt JA Lephart SM 2015
50 6 S266
Trunk biomechanics and its association with hip and knee kinematics in patients with and without patellofemoral pain Man Ther Nakagawa TH Maciel CD Serrão FV 2015
20 1 189 194 1532-2769 25261089
Core strength and lower extremity alignment during single leg squats Med Sci Sports Exerc Willson John D Ireland Mary Lloyd Davis Irene 2006
38 5 945 952 0195-9131 16672849
Deficits in neuromuscular control of the trunk predict knee injury risk: prospective biomechanical-epidemiologic study Am J Sports Med Zazulak Bohdanna T Hewett Timothy E Reeves N Peter Goldberg Barry Cholewicki Jacek 2007
35 7 1123 1130 0363-5465 17468378
Management of the sensorimotor system. The lower limb Grieve's Modern Musculoskeletal Physiotherapy Clark NC Lephart SM Jull G. Moore A. Falla D. Lewis J. McCarthy C. Sterling M. Elsevier Edinburgh 2015
319 327
Isokinetics. Muscle Testing, Interpretations, and Clinical Applications Dvir Z Churchill Livingstone Edinburgh 2004

The Influence of hip strength on knee kinematics during a single-legged medial drop landing among competitive colleagiate basketball players Int J Sports Phys Ther Suzuki Hidetomo Omori Go Uematsu Daisuke Nishino Katsutoshi Endo Naoto 2015
10 5 592 601 26491609
Gender differences in rotation of the shank during single-legged drop landing and its relation to rotational muscle strength of the knee Am J Sports Med Kiriyama Shinya Sato Haruhiko Takahira Naonobu 2009
37 1 168 174 0363-5465 18936276
Relationship between selected measures of strength and hip and knee excursion during unilateral and bilateral landings in women J Strength Cond Res McCurdy Kevin Walker John Armstrong Rusty Langford George 2014
28 9 2429 2436 1064-8011 24942172
Weaker lower extremity muscle strength predicts traumatic knee injury in youth female but not male athletes BMJ Open Sport Exerc Med Augustsson Sofia Ryman Ageberg Eva 2017
3 1 e000222
Hip muscle strength predicts noncontact anterior cruciate ligament injury in male and female athletes: a prospective study Am J Sports Med Khayambashi Khalil Ghoddosi Navid Straub Rachel K Powers Christopher M 2016
44 2 355 361 0363-5465 26646514
The relationship of hamstrings and quadriceps strength to anterior cruciate ligament injury in female athletes Clin J Sport Med Myer Gregory D Ford Kevin R Foss Kim D Barber Liu Chunyan Nick Todd G Hewett Timothy E 2009
19 1 3 8 1050-642X 19124976
Intra-rater reliability, measurement precision, and inter-test correlations of 1RM single-leg leg-press, knee-flexion, and knee-extension in uninjured adult agility-sport athletes: Considerations for right and left unilateral measurements in knee injury control Phys Ther Sp Clark Nicholas C Reilly Lee J Davies Stephanie C 2019
40 128 136 1466-853X
The influence of the improvement of calf strength on barefoot loading J Biomimetics, Biomaterials Biomed Eng Cen Xuan Zhen Liang Zhi Qiang Gao Zi Xiang Lian Wen Lan Wang Zhang Ming 2019
40 16 25
Effects of plyometric exercise on muscle soreness and plasma creatine kinase levels and its comparison with eccentric and concentric exercise J Strength Cond Res Jamurtas A Fatouros I Buckenmeyer P Kokkinidis E Taxildaris K Kambas A Kyriazis G 2000
14 1 68 74 1064-8011
The relationship between vertical hop performance and open and closed kinetic chain muscle strength of the lower limb J Sports Sci Clark Nicholas Gumbrell Clare J Rana Sarah Traole Carole M Morrissey Matthew C 2001
19 1 18 19
Posture Principles Neural Science Macpherson J Horak F Kandel E. Schwartz J. Jessell T. Siegelbaum S. McGraw-Hill New York 2013
935 938
Associations between single-leg postural control and drop-landing mechanics in healthy women J Sport Rehabil Durall Christopher J Kernozek Thomas W Kersten Melissa Nitz Maria Setz Jonathan Beck Sara 2011
20 4 406 418 1543-3072 22012495
Star Excursion Balance Test as a predictor of lower extremity injury in high school basketball players J Orthop Sports Phys Ther Plisky Phillip J Rauh Mitchell J Kaminski Thomas W Underwood Frank B 2006
36 12 911 919 0190-6011 17193868
The reliability of an instrumented device for measuring components of the star excursion balance test N Am J Sports Phys Ther Plisky Phillip J Gorman Paul P Butler Robert J Kiesel Kyle B Underwood Frank B Elkins Bryant 2009
4 2 92 21509114
Dynamic balance performance and noncontact lower extremity injury in college football players: an initial study Sports Health Butler Robert J Lehr Michael E Fink Michael L Kiesel Kyle B Plisky Phillip J 2013
5 5 417 422 1941-7381 24427412
Association of Y Balance Test reach asymmetry and injury in division I athletes Med Sci Sports Exerc Smith CA Chimera NJ Warren M 2015
47 1 136 141 1530-0315 24870573
Balance index score as a predictive factor for lower sports results or anterior cruciate ligament knee injuries in Croatian female athletes - preliminary study Coll Antropol Vrbanić TS Ravlić-Gulan J Gulan G Matovinović D 2007
31 1 253 258 0350-6134 17598410
Prevalence and magnitude of preseason clinically-significant single-leg balance and hop test asymmetries in an English adult netball club Phys Ther Sp Clark Nicholas C Mullally Elaine M 2019
40 44 52 1466-853X
Effect of neurocognition and concussion on musculoskeletal injury risk Curr Sports Med Rep Herman Daniel C Zaremski Jason L Vincent Heather K Vincent Kevin R 2015
14 3 194 199 25968852
The assessment of sport-related concussion: the evidence behind neuropsychological testing and management Clin J Sport Med Grindel Scott H Lovell Mark R Collins Michael W 2001
11 3 134 143 1050-642X 11495317
Visual-spatial memory deficits are related to increased knee valgus angle during a sport-specific sidestep cut Am J Sports Med Monfort Scott M Pradarelli Jared J Grooms Dustin R Hutchison Keith A Onate James A Chaudhari Ajit MW 2019
47 6 1488 1495 0363-5465 30986095
Validity of ImPACT for measuring processing speed following sports-related concussion Journal of Clinical and Experimental Neuropsychology Iverson GL Lovell MR Collins MW 2005
27 6 683 689 1380-3395 16019644
Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) Applications, Inc Lovell MR 2020
2020-7-11 https://impacttest.com/
Measurement of symptoms following sports-related concussion: reliability and normative data for the post-concussion scale Appl Neuropsychol Lovell MR Iverson GL Collins MW Podell K Johnston KM Pardini D Pardini J Norwig J Maroon JC 2006
13 3 166 174 0908-4282 17361669
Neurocognitive reaction time predicts lower extremity sprains and strains International Journal of Athletic Therapy and Training Wilkerson Gary B 2012
17 6 4 9
The relationship between neurocognitive function and noncontact anterior cruciate ligament injuries Am J Sports Med Swanik CB Covassin T Stearne DJ Schatz P 2007
35 6 943 948 0363-5465 17369562
The reliability and criterion validity of 2D video assessment of single leg squat and hop landing J Electromyogr Kinesiol Herrington L Alenezi F Alzhrani M Alrayani H Jones R 2017
34 80 85 1873-5711 28437781
Comparison of two-dimensional measurement techniques for predicting knee angle and moment during a drop vertical jump Clin J Sport Med Mizner Ryan L Chmielewski Terese L Toepke John J Tofte Kari B 2012
22 3 221 227 22544058
Two-and three-dimensional relationships between knee and hip kinematic motion analysis: single-leg drop-jump landings J Sport Rehabil Sorenson Bryan Kernozek Thomas W Willson John David Ragan Robert Hove Jordan 2015
24 4 363 372 1543-3072 25658442
Quantifying frontal plane knee motion during single limb squats: Reliability and validity of 2‐dimensional measures Int J Sports Phys Ther Gwynne Craig R Curran Sarah A 2014
9 7 898 906 25540705
Two-dimensional video analysis is comparable to 3D motion capture in lower extremity movement assessment Int J Sports Phys Ther Schurr Stacy A Marshall Ashley N Resch Jacob E Saliba Susan A 2017
12 2 163 172 28515970
The relationship between performance of a single-leg squat and leap landing task: moving towards a netball-specific anterior cruciate ligament (ACL) injury risk screening method Sports Biomechanics Fox Aaron S Bonacci Jason Saunders Natalie 2018
19 4 1 17 1476-3141 29781788
Reliability of the landing error scoring system-real time, a clinical assessment tool of jump-landing biomechanics J Sport Rehabil Padua Darin A Boling Michelle C DiStefano Lindsay J Onate James A Beutler Anthony I Marshall Stephen W 2011
20 2 145 156 1543-3072 21576707
Tuck jump assessment for reducing anterior cruciate ligament injury risk Athl Ther Today Myer Gregory D Ford Kevin R Hewett Timothy E 2008
13 5 39 44 1078-7895 19936042
A preliminary investigation to establish the criterion validity of a qualitative scoring system of limb alignment during single-leg squat and landing Journal of Exercise, Sports, and Orthopedics Herrington Lee Munro Allan 2014
1 2 1 6
Investigation of clinician agreement in evaluating movement quality during unilateral lower extremity functional tasks: a comparison of 2 rating methods J Orthop Sports Phys Ther Chmielewski Terese L Hodges Michael J Horodyski MaryBeth Bishop Mark D Conrad Bryan P Tillman Susan M 2007
37 3 122 129 0190-6011 17416127
Efficacy of ACL injury risk screening methods in identifying high‐risk landing patterns during a sport‐specific task Scand J Med Sci Sports Fox AS Bonacci J McLean SG Saunders N 2017
27 5 525 534 0905-7188 27292768
The inter and intra rater reliability of the Netball Movement Screening Tool J Sci Med Sport Reid Duncan A Vanweerd Rebecca J Larmer Peter J Kingstone Rachel 2015
18 3 353 357 1440-2440 24930074
Neuromuscular training improves movement competency and physical performance measures in 11–13-year-old female netball athletes J Strength Cond Res Hopper Amanda Haff Erin E Barley Oliver R Joyce Christopher Lloyd Rhodri S Haff G Gregory 2017
31 5 1165 1176 1064-8011 28135219
Can two-dimensional video analysis during single-leg drop vertical jumps help identify non-contact knee injury risk? A one-year prospective study Clin Biomech Dingenen Bart Malfait Bart Nijs Stefaan Peers Koen HE Vereecken Styn Verschueren Sabine MP Staes Filip F 2015
30 8 781 787 0268-0033
Two-dimensional motion analysis of dynamic knee valgus identifies female high school athletes at risk of non-contact anterior cruciate ligament injury Knee Surg Sports Traumatol Arthrosc Numata Hitoaki Nakase Junsuke Kitaoka Katsuhiko Shima Yosuke Oshima Takeshi Takata Yasushi Shimozaki Kengo Tsuchiya Hiroyuki 2018
26 2 442 447 0942-2056 28840276
The Landing Error Scoring System as a screening tool for an anterior cruciate ligament injury–prevention program in elite-youth soccer athletes J Athl Train Padua Darin A DiStefano Lindsay J Beutler Anthony I De La Motte Sarah J DiStefano Michael J Marshall Steven W 2015
50 6 589 595 1062-6050 25811846
Functional performance testing following knee ligament injury Phys Ther Sp Clark Nicholas C 2001
2 2 91 105 1466-853X
Development of a netball specific dynamic balance assessment [MPhil], Auckland University of Technology Lavipour Daniel Auckland University of Technology 2011

Rehabilitation after ACL reconstruction: function testing Orthopedics Barber S Noyes F Mangine R DeMaio M 1992
15 8 969 974 1508774
Sport-specific functional performance tests for the ACL insufficient athlete J Athl Train Lephart S Perrin D Minger K Fu F Gieck J 1989
24 2 119
Intratester reliability and measurement error of the adapted crossover hop for distance Phys Ther Sp Clark Nicholas C Gumbrell Clare J Rana Sarah Traole Carole M Morrissey Matthew C 2002
3 3 143 151 1466-853X
Abnormal lower limb symmetry determined by function hop tests after anterior cruciate ligament rupture Am J Sports Med Noyes FR Barber SD Mangine RE 1991
19 5 513 518 0363-5465 1962720
Preseason functional test scores are associated with future sports injury in female collegiate athletes J Strength Cond Res Brumitt Jason Heiderscheit Bryan C Manske Robert C Niemuth Paul E Mattocks Alma Rauh Mitchell J 2018
32 6 1692 1701 1064-8011 28930873
Lower extremity functional tests and risk of injury in Division III collegiate athletes Int J Sports Phys Ther Brumitt Jason Heiderscheit Bryan C Manske Robert C Niemuth Paul E Rauh Mitchell J 2013
8 3 216 227 23772338
Relationship between lower limb motor performance measures relevant to knee injury control in uninjured adult netball players Knee Surg Sports Traumatol Arthrosc Clark NC Mullally Elaine M 2018
26 S165 166
The effect of hypermobility on the incidence of injuries in elite-level professional soccer players: a cohort study Am J Sports Med Konopinski Matt D Jones Gareth J Johnson Mark I 2012
40 4 763 769 0363-5465 22178581
Lower-limb motor-performance asymmetries in English community-level female field hockey players: Implications for knee and ankle injury prevention Phys Ther Sp Clark Nicholas C Clacher Lucy H 2020
43 43 51 1466-853X
Performance enhancement following a strength and injury prevention program: A 26-week individualized and supervised intervention in adolescent female volleyball players International Journal of Sports Science and Coaching Augustsson Sofia Ryman Augustsson Jesper Thomeé Roland Karlsson Jon Eriksson Bengt I Svantesson Ulla 2011
6 3 399 417
More data needed on injury risk among young elite athletes Br J Sports Med Steffen Kathrin Engebretsen Lars 2010
44 7 485 489 0306-3674 20460261
The effects of individualized resistance strength programs on knee muscular imbalances in junior elite soccer players PloS One Śliwowski Robert Jadczak Łukasz Hejna Rafał Wieczorek Andrzej 2015
10 12 e0144021 1932-6203 26630271
