ACL Injury Prevention
Strengthening: Quadriceps
**want in closed-chain! - if not, get a lot more anterior translation of tibia from quads Squats, lunges, single leg squat, single leg lunge, step ups/downs, wall sits, leg extensions, leg press
Contact Injuries
- high-impact stress - anterior into hyperextension - lateral-valgus stress
Non-contact ACL Injuries
2/3 of all ACL injuries - landing: valgus position (landing either way out lateral or right in front of them) - cutting: varus with IR or valgus with ER - deceleration: high quad activity, anterior tibial translation
Single Leg Squat
Arm on hips of chest Squat down as far as possible 5x Rate posture, hip & knee position, overall quality correlates with hip abductor strength
Broad, broad, stick (or up)
Complete repetitive broad jumps, avoid moving forward on last jump Absorb horizontal momentum or transfer to vertical if completeing up
Drop-Jump Test
Drop from step to mark on floor with two legs Jump straight up after landing & attempt to land on same spot Assess knee separation, ankle separation, landing spot - defects knee control on landing *take off posture is just as important as landing*
Cone Jumps/Hops
Feet shoulder width apart Jump cone laterally & land softly with knees flexed then jump back over cone Correct double bounce, staggered feet or feet separation to clear cone
Broad Jump
Feet shoulder width apart, squat knees over toes --> explode forward (looking at form, not distance) Land with knees & hips bent, hold landing position Avoid genu valgus takeoff & landing
Risk Factors
Females 2-5x more likely most likely d/t Q angle, tibial plateau geometry, and hormones -intercondylar notch geometry -ligament laxity -BMI -environmental factors such as weather
MOI
Forced hyperextension Extreme rotation with valgus stress
Bounding in Place
Good to see if someone has control or not Take off bringing one knee up towards chest, lift opp. arm towards head --> land on take off leg *can be difficult to coordinate*
Flexibility
HS Quads Gastroc/Soleus ITB Hip flexors Low back Pecs Abdominals
Dynamic Warm-up
High knees Straight leg march Hurdle walk Heel/toe walk Forward lunges Butt kickers
Quadriceps Forces
High quad contraction at low flexion angles HS:Quad ratio - normal = 50-80% - high performance runners closer to 100% (HS=quads)
High Risk Situations
Highest risk for ACL tear during DECELERATION, cutting, landing Positions of risk: -knee ext --> train to land on flexed knee -hip ext --> train to land in hip flexion -knee valgus --> train to keep knees forward -LOB/poor skill --> train agility & dynamic balance -pronation--> research is mixed
Hop, hop stick
Hop for distance landing on takeoff leg, repeat multiple hops, and stay in landing position on last landing Make sure they hold & are in control
Anterior Cruciate Ligament (ACL)
Large amount of mechanoreceptors Controls anterior translation of tibia on femur Secondary restraint to valgus & rotational forces
Squat Jumps
Lower into squat, knees behind toes --> explode up Land softly with knees flexed & go down into squat then repeat! Avoid genu valgum & stay balanced
Shuttle Run and Vertical Jump
Not predictors of injury Used as baseline measurements to compare post-tx Used to train mechanics and feedback to avoid "injury position"
Strengthening: Core
Planks, side planks, medicine ball toss, swiss ball exercises, russian twists, scapular retractions, push up plus
Noncontact ACL Injuries: Forces
Postural control - trunk control - hip-knee-ankle Knee alignment Muscle -HS:quad ratio --> quads fire to keep you upright, but w/o HS co-contraction/fight, quads pull too hard -fatigue Neuromuscular -muscle pattern -reaction
Testing
Posture Core endurance (plank, side bridge, curl-up) -- want it to fire and last Hip, knee, ankle ROM Strength testing -- hip ABD, ER, quads, HS, all ankle HS and gastroc length tests (want long & strong)
Functional Tests
Single hop test Triple hop Crossover hop Single leg squats Step down Drop-jump test Shuttle run Vertical jump
Tuck Jumps
Slight bend from knees & hips --> explode upward Land slightly bent knees & hips, softly with knees straight ahead Bring knees to chest, not chest to knees & do not double bounce (just straight up & down)
Wall Jumps
Slight bend in knees Reach overhead & try to tap same spot on wall Land softly with knees straight ahead Correct for slumped posture & excessive knee bend Do not allow participant to look at feet
Strengthening: Glutes
Squats, lunges, wall sits, bridges, prone extension, leg press, hip extension machine, single leg lunge with back foot on bench Throw in balance components to really work them
Hopping Tests (single, crossover, triple)
Stand on one foot and jump for DISTANCE Compare limbs Look for control - fall = poor - wobble = fair - control = good
Agility
Teach deceleration technique - want strong glutes to help decelerate b/c need to get leg back underneath you & already in a flexion moment so to get back need to extend hips w/ glutes
Plyometrics
Wall jumps Tuck jumps Squat jumps Cone jumps Broad jump 180 degree jump Broad, broad, stay Single leg hops Hop, hop, stay Mix of multiple jumps/hops
ACL Injury Prevention Programs
Warm-up Plyometrics (jump training) Flexibility Strengthening (core, LE) - quads, glutes, HS, hip ABD/ER, core Agility
Strengthening: Hip ABD/ER
hip abduction with theraband, airplanes -- single leg rotation, lateral step with theraband, russian hamstring curl, monster walks with Theraband, hip dips, bridges with theraband
Strengthening: Hamstrings
squats w/ anterior body lean, single leg bridge with press up, single leg deadlift, russian hamstring curl, hamstring curl machine, swiss ball rolls Get foot underneath for hamstrings to fire more