BackgroundFemale athletes participating in high-risk sports suffer anterior cruciate ligament injury at a 4- to 6-fold greater rate than do male athletes.HypothesisPrescreened female athletes with subsequent anterior cruciate ligament injury will demonstrate decreased neuromuscular control and increased valgus joint loading, predicting anterior cruciate ligament injury risk.Study DesignCohort study; Level of evidence, 2.MethodsThere were 205 female athletes in the high-risk sports of soccer, basketball, and volleyball prospectively measured for neuromuscular control using 3-dimensional kinematics (joint angles) and joint loads using kinetics (joint moments) during a jump-landing task. Analysis of variance as well as linear and logistic regression were used to isolate predictors of risk in athletes who subsequently ruptured the anterior cruciate ligament.ResultsNine athletes had a confirmed anterior cruciate ligament rupture; these 9 had significantly different knee posture and loading compared to the 196 ...

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Biomechanical Measures of Neuromuscular Control and Valgus Loading of the Knee Predict Anterior Cruciate Ligament Injury Risk in Female Athletes A Prospective Study

This study examined the mechanisms of anterior cruciate ligament (ACL) injury In the first part of the study, using a comprehensive, standardized questionnaire, 89 athletes (100 knees) were interviewed about the events surrounding their ACL injury A noncontact mechanism was reported in 71 (72%) knees and a contact injury in 28 (28%) knees; one patient was unsure if there was any contact Most of the injuries were sustained at footstrike with the knee close to full extension Noncontact mechanisms were classified as sudden deceleration prior to a change of direction or landing motion, while contact injuries occurred as a result of valgus collapse of the knee Hamstring flexibility parameters revealed a statistically higher level of laxity in the injured athletes compared with a matched group of 28 controls In the second part of the study, videotapes of 27 separate ACL disruptions were reviewed and confirmed that most noncontact injuries occur with the knee close to extension during a sharp deceleration or landing maneuver Because the knee is in a position to allow the extensor mechanism to strain the ACL and maximum, eccentric muscle force conditions usually apply, the quadriceps may play an important role in ACL disruption Passive protection of the ACL by the hamstring muscles may be reduced in patients with above-average flexibility

Mechanisms of anterior cruciate ligament injury.

To prospectively evaluate the effect of neuromuscular training on the incidence of knee injury in female athletes, we monitored two groups of female athletes, one trained before sports participation and the other not trained, and a group of untrained male athletes throughout the high school soccer, volleyball, and basketball seasons. Weekly reports included the number of practice and competition exposures and mechanism of injury. There were 14 serious knee injuries in the 1263 athletes tracked through the study. Ten of 463 untrained female athletes sustained serious knee injuries (8 noncontact), 2 of 366 trained female athletes sustained serious knee injuries (0 noncontact), and 2 of 434 male athletes sustained serious knee injuries (1 noncontact). The knee injury incidence per 1000 athlete-exposures was 0.43 in untrained female athletes, 0.12 in trained female athletes, and 0.09 in male athletes (P = 0.02, chi-square analysis). Untrained female athletes had a 3.6 times higher incidence of knee injury than trained female athletes (P = 0.05) and 4.8 times higher than male athletes (P = 0.03). The incidence of knee injury in trained female athletes was not significantly different from that in untrained male athletes (P = 0.86). The difference in the incidence of noncontact injuries between the female groups was also significant (P = 0.01). This prospective study demonstrated a decreased incidence of knee injury in female athletes after a specific plyometric training program.

/pdf/the-effect-of-neuromuscular-training-on-the-incidence-of-41me19qrrs.pdf

The Effect of Neuromuscular Training on the Incidence of Knee Injury in Female Athletes A Prospective Study

ObjectiveTo describe the mechanisms for anterior cruciate ligament injuries in female team handball.Study DesignDescriptive video analysis.MethodsTwenty videotapes of anterior cruciate ligament injuries from Norwegian or international competition were collected from 12 seasons (1988-2000). Three medical doctors and 3 national team coaches systematically analyzed these videos to describe the injury mechanisms and playing situations. In addition, 32 anterior cruciate ligament-injured players in the 3 upper divisions in Norwegian team handball were interviewed during the 1998-1999 season to compare the injury characteristics between player recall and the video analysis.ResultsTwo main injury mechanisms for anterior cruciate ligament injuries in team handball were identified. The most common (12 of 20 injuries), a plant-and-cut movement, occurred in every case with a forceful valgus and external or internal rotation with the knee close to full extension. The other main injury mechanism (4 of 20 injuries), a 1...

Injury Mechanisms for Anterior Cruciate Ligament Injuries in Team Handball A Systematic Video Analysis

Study Design Prospective cohort. Objective To determine if Star Excursion Balance Test (SEBT) reach distance was associated with risk of lower extremity injury among high school basketball players. Background Although balance has been proposed as a risk factor for sports-related injury, few researchers have used a dynamic balance test to examine this relationship. Methods and Measures Prior to the 2004 basketball season, the anterior, posteromedial, and posteralateral SEBT reach distances and limb lengths of 235 high school basketball players were measured bilaterally. The Athletic Health Care System Daily Injury Report was used to document time loss injuries. After normalizing for lower limb length, each reach distance, right/left reach distance difference, and composite reach distance were examined using odds ratio and logistic regression analyses. Results The reliability of the SEBT components ranged from 0.82 to 0.87 (ICC3,1) and was 0.99 for the measurement of limb length. Logistic regression models ...

https://www.jospt.org/doi/pdf/10.2519/jospt.2006.2244

Star Excursion Balance Test as a Predictor of Lower Extremity Injury in High School Basketball Players

The purpose of this study was to test the effect of a jump-training program on landing mechanics and lower extremity strength in female athletes involved in jumping sports. These parameters were compared before and after training with those of male athletes. The program was designed to decrease landing forces by teaching neuromuscular control of the lower limb during landing and to increase vertical jump height. After training, peak landing forces from a volleyball block jump decreased 22%, and knee adduction and abduction moments (medially and laterally directed torques) decreased approximately 50%. Multiple regression analysis revealed that these moments were significant predictors of peak landing forces. Female athletes demonstrated lower landing forces than male athletes and lower adduction and abduction moments after training. External knee extension moments (hamstring muscle-dominant) of male athletes were threefold higher than those of female athletes. Hamstring-to-quadriceps muscle peak torque ratios increased 26% on the nondominant side and 13% on the dominant side, correcting side-to-side imbalances. Hamstring muscle power increased 44% with training on the dominant side and 21% on the nondominant. Peak torque ratios of male athletes were significantly greater than those of untrained female athletes, but similar to those of trained females. Mean vertical jump height increased approximately 10%. This training may have a significant effect on knee stabilization and prevention of serious knee injury among female athletes.

Amanda L. Stroupe

Papers

Plyometric Training in Female Athletes Decreased Impact Forces and Increased Hamstring Torques