Risk Factors for Anterior Cruciate Ligament (ACL) Injury

Study Overview
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Brief Summary
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The anterior cruciate ligament (ACL) is located inside the knee joint and provides stability to the knee. ACL injuries occur more frequently in women than men; the reason for this is unknown. The purpose of this study is to determine gender-specific anatomical, hormonal, and demographic risk factors for ACL injury. This observational cohort study will only enroll incoming cadets at the U.S. Naval, Air Force, or Military Academies. Study hypothesis: Human movement factors, including key kinetics and kinematics of the knee during a jump-landing task, are associated with the rate of ACL injury.

Detailed Description
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The ACL stabilizes the knee joint by preventing the shinbone (tibia) from sliding forward beneath the thighbone (femur). A hard twist or excessive pressure on the ACL can tear or rupture the ligament, resulting in high levels of short-term disability and extensive rehabilitation. Previous data indicate that women who participate in sports or who are otherwise physically active have higher rates of ACL injury than men; the reason for this is unknown. There are four groups of potential risk factors for ACL injury: environmental, anatomical, hormonal, and biomechanical or neuromuscular. In particular, poor technique when landing from a jump (also known as jump-landing) is proposed as a specific neuromuscular risk factor of interest in this study. This study will determine gender-specific anatomical, hormonal, and demographic risk factors for ACL injury, as well as quantify gender-specific differences in jump-landing technique and other neuromuscular risk factors. This observational cohort study will enroll 4,800 cadets at the three large U.S. military academies; approximately 50% of those enrolled will be women. Only incoming cadets at the U.S. Naval, Air Force, or Military Academies will be able to participate. Each study participant will undergo a baseline assessment that will include measurement of neuromuscular risk factors using motion analysis, strength testing, and standardized assessment of poor jump-landing technique using the Landing Error Score System (LESS). All participants will be followed for up to 4 years. ACL injuries will be prospectively identified; an injury questionnaire is administered to participants who sustain an ACL injury while they are cadets. Otherwise, there is no further contact.

Official Title
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Epidemiology of Jump-Landing Movements and ACL Injury

Conditions
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Knee Injuries, Athletic Injuries

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Incoming cadet at the U.S. Naval, Air Force, or Military Academies

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| 1<br>Incoming cadets at the U.S. Naval, Air Force, or Military Academies | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Biomechanics, Neuromuscular, Lower limb, Injury, ACL, Anterior Cruciate Ligament injury