Knee Hyperextension
Conditions
Keywords
Injury rate
Brief summary
Knee hyperextension, also called genu recurvatum or back knee, is commonly seen in women, people with ligamentous laxity, stroke and cerebral palsy patients. This faulty posture would result in excessive tension of the passive tissues such as anterior cruciate ligament (ACL) and posterior capsule of the knee. Subjects may also develop compensations at hip and ankle joint, as well as lower extremity malalignment. Muscles surrounding the knee could also become dysfunctional when performing functional tasks requiring stability during terminal knee extension, during which uncontrolled knee hyperextension could easily be utilized to lock the joint for stability in gait and stair climbing. In athletes, landing from a jump on an extended knee is one of the common reasons resulting in ACL injury. Little is known about the injury rate of athletes with knee hyperextension who participate in sports involving jump-landing activities. The aim of the study is to explore if knee hyperextension is associated with poor lower extremity alignment and dynamic control and injury rate in athletes requiring jump-landing activities. One of the study hypothesis is that athlete with knee hyperextension can find more compensatory lower extremity alignments and poor control in dynamic movement than control group. The other hypothesis is with or without knee hyperextension, the parameter of lower extremity alignment and dynamic control can predict injury rate in jump landing athlete.
Detailed description
Investigators expect to recruit 100 subjects into 2 group- control group and knee hyperextension group (KH group). In knee hyperextension group, investigators will include college athletes having knee hyperextension alignment, no lower extremity injuries in past three months, and participating in jump-landing activities. Control group will match the gender, age, height, weight and sports to KH group. Inclusion criteria is the same as KH group, except the knee hyperextension angle is \<5⁰ in control group. Every subjects will receive the first time assessment and follow up by filling the injury-follow-up form every months for about four months. At the first assessment, investigators will measure lower extremity alignments include pelvic angle in sagittal plane, hip anteversion, tibiofemoral angle, knee hyperextension angle in supine and standing position, tibial rotation angle, and navicular drop; lower extremity muscle flexibility include rectus femoris, hamstrings, gastrocnemius, soleus, iliotibial band; lower extremity muscle strength include hip, knee, muscle group; dynamic control task will record tibio-femoral acceleration, angle change ground reaction force and EMG muscle firing during vertical jump and drop jump.
Interventions
None listed
Sponsors
National Yang Ming Chiao Tung University
Study design
Observational model
CASE_CONTROL
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
20 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* age ≥ 20 years old * knee hyperextension ≥ 5⁰ * participate in jump- landing sports * training at least 3 days per week * no lower extremity injury last 3 months
Exclusion criteria
* having knee surgery before * In the past three months have occurred lower extremity musculoskeletal injury leading the person can't participate in training or competition for at least three days
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Injury type | 4 months | Record injury type |
| Injury duration | 4 months | time loss during the game or training (days) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Lower extremity alignments-tibiofemoral angle | 1st day | tibiofemoral angle in degree |
| Lower extremity alignments-knee hyperextension angle | 1st day | knee hyperextension angle in supine and standing posture in degree |
| Lower extremity alignments-tibial rotation angle | 1st day | tibial rotation angle in degree |
| Lower extremity alignments-hip external rotation angle | 1st day | hip external rotation angle in degree |
| Lower extremity alignments-hip internal rotation angle | 1st day | hip internal rotation angle in degree |
| Lower extremity alignments-navicular drop | 1st day | navicular drop normalized with foot length in % |
| Rectus femoris flexibility | 1st day | measure knee angle in prone knee bend position |
| Hamstrings flexibility | 1st day | measure knee angle in 90-90 straight leg raise test |
| Lower extremity alignments-pelvic tilt on sagittal plane | 1st day | pelvic tilt on sagittal plane in degree |
| Soleus flexibility | 1st day | measure ankle dorsiflexion angle in knee flex standing position without rearfoot lift off the floor |
| Iliotibial band flexibility | 1st day | use Ober's test to measure the angle below horizontal level |
| Dynamic task parameters-acceleration and angle | 1st day | anteroposterior acceleration and angle changes at knee joint |
| Dynamic task parameters-ground reaction force | 1st day | ground reaction force |
| Dynamic task parameters-Electromyography (EMG) | 1st day | use EMG to detect muscle firing during jump task |
| knee extensors muscle strength | 1st day | knee extensors by hand held dynamometer |
| knee flexors muscle strength | 1st day | knee flexors by hand held dynamometer |
| Gastrocnemius flexibility | 1st day | measure ankle dorsiflexion angle in standing position without rearfoot lift off the floor |
| Lower extremity alignments-hip anteversion | 1st day | hip anteversion in degree |
Countries
Taiwan
Outcome results
None listed