411 - knee
non-modifiable risk factors for ACL injury
-age (less than 20) -gender (female) -hormone stress (without contraception) -sports (soccer, skiing, handball, basketball common sports to get injured) -narrow intercondylar notch -generalized ligamentous laxity -synthetic floor or turf -poor weather (for outdoor sports) -infectious disease -history of muscle, tendon, knee or ankle injury
modifiable risk factors for ACL injury
-dynamic valgus -low flexion of hip and knee during landing -poor hip and trunk control -weakness of knee flexors -weakness of hip abductors -delayed activation of flexors -muscle fatigue -proprioceptive deficits -poor general fitness
extrinsic factors for female athletes ACL tear
-lower body strength and training -poor neuromuscular control -footwear and surface interaction -biomechanics of jumping and landing
D/Dx for knee injury
-patella fracture -patellar tendinopathy/tendinitis -lateral/medial meniscal tear -bursitis -osteoarthritis -rheumatoid arthritis -lymes disease -neuropathy (nerve damage) -ligament tear (ACL, MCL, LCL, PCL) -IT band injury -joint injury -muscle strain -popliteus tendinitis
intrinsic/anatomical factors in female ACL injuries
-smaller intercondylar notch -smaller ACL size -wider hips -larger Q angle -hormones (w/o contraception; estrogen and relaxin are highest during mid cycle --- most likely to ear) -biomechanics (females lands worse than males when jumping) -muscular imbalances (quad to hamstring rotation is 80:20 vs 60:40)
extension
0
3 screening tests (in article)
1. drop jump screening test 2. single leg squat test 3. functional movement screen test
3 most dangerous non-contact situations for ball sports and ACL sprains
1. landing after a jump 2. abrupt stopping 3. sudden direction change (including rotary knee motion)
4 limitations of Mortvedt article study (4)
1. only assessed players movements from frontal plane view only 2. picture quality and zoom factor differed slightly between tests 3. visual inspection of joint kinematics in complex tasks has been proven to be less accurate 4. some players in the non-injury group would sustain an ACL injury after the observation period (misclassifies them)
incidence for ACL tear
1/3500 (over 200,000 injuries)
flexion
135
% re-injury rate for ACL
15
internal rotation
30
lachmans test - patient in supine position with leg bent to __ degrees
30
most ACL tears are what degree
3rd
external rotation
40
prevalence for ACL injury - account for what % of all knee injuries
50 (2nd injury to ankle sprains)
cost for ACL injury in evaluation, treatment and rehab
500 billion
competition level return rate (%)
55
on the side the ACL was torn, patients were ___% more likely to have a previous unilateral ankle sprain (on that same side)
60
preinjury level return rate (%)
65
incidence is _ times higher in games vs practice
7
__% ACL sprains require surgery
80
same activity return rate (%)
81
sensitivity and specificity of MRI respectively (%)
86, 95
anterior drawer test - patient is in supine position with leg bent to__ degrees
90
O'Donoghue's Triad (unhappy triad)
ACL sprain, MCL sprain, medial meniscal tear (order in which usually torn; feel a pop in knee)
henning program
ACL tear prevention program for basketball players
vermont ACL prevention program
ACL tear prevention program for skiers
4 ligaments that hold the patella in place
ACL, PCL, LCL, MCL (anterior and posterior cruciate & lateral and medial collateral)
Q angle: angle between 2 lines -- these two lines are between:
ASIS - midpoint of patella and tibial tuberosity - midpoint of patella (Q angle changes the force that your quads are pulling the patella)
what is the gold standard for diagnosing ACL injury
MRI (most commonly used and really good at the knee)
SNOUT
Sensitive test with a Negative result rules OUT disease
SPIN
Specific test with Positive result rules IN disease
T/F. patients must be relaxed in order to perform exams
T
goal for both anterior drawer and lachmans test
anterior displacement of tibia
if you have a large athlete and small examiner, which test should the examiner do
anterior drawer
objective exams (3)
anterior drawer, lachmans, pivot shift
for a pivot shift test, the examiner..
applied valgus force on outside of knee and internally rotates tibia
joint moving
arthrokinematics
4 times more ACL tears in womens..
basketball players
knee joints are ____ diarthroidal
biaxial
intrinsic factors for ACL injury
biochemical, own ligament and muscle strength, hormone levels, sex, age
define 3rd degree ACL tear
complete rupture all the way through the middle of the ligament
screw home mechanism
describes how the knee flexes and extends with internal and external rotation
extrinsic factors for ACL injury
environment, shoe type, playing surface, sport, equipment
aim of the Mortvedt study
examine if sports medicine pros and coaches are able to identify players at risk for ACL injury by visually assessing player performance during a VDJ test
when the knee is fully extended (0), the tibia is at max..
external rotation (quads are contracting)
autograft
graft from a person's own body (BPB - bone patella bone graft or hamstring graft)
allograft
graft from another person or a cadaver (cadaver graft)
non-contact MOI for ACL
hyperextension and straight rotation with deceleration
if the pivot shift test is positive,
immediate joint line pain, tibia will sublux posteriorly (use this test if there are other parts other than ACL involved)
when the knee is flexed (135), the tibia is at mas
internal rotation (popliteus is contracting and causes the tibia to internally rotate)
avulsion tears are common in
kids (people who have open growth plates)
which test is most accurate
lachmans
which objective exam is the "gold standard" for detecting an ACL injury
lachmans test
most ACl tears happen in the ____ of the ligament
midsubstance
where the results of the area under curve for assessing risk rating ability high? how did it compare to a coin toss
no. ranged from 0.3-0.6 with a mean score of 0.47; results were NO better than tossing a coin
bones moving
osteokinematics
which test is most painful for the patient
pivot shift test
PEP program
prevent injury and enhance performance program; prevents ACL injuries in football
anterior compartment thigh muscles
rectus femoris, vastus lateralis, vastus medialis, vastus intermedius, tensor vastus intermedius, sartorius, TFL
3 pes anserine muscles (conjoined tendons of these 3 muscles)
sartorius, gracilis, semitendinosus
3-2 times more common to tear ACL in womens...
soccer players and gymnasts
cincinnati sportsmetric training program
tested on football, volleyball, and basketball athletes; consists of different jumping exercises with increasing complexity
knee joints (3)
tibiofemoral, patellofemoral, proximal tibiofibular
internal and external rotation occur in which plane
transverse
contact MOI for ACL
valgus force with rotation (force coming from outside source)
VDJ test
vertical drop jump test (visual observation; inexpensive and fast)
higher ACL tear rates are found among ___ in which 3 sports
women, team handball, volleyball, alpine skiing
is there a relationship between ACL tears and LAS
yes (on the sign that ACL was injured, patients were 60% more likely to have a previous unilateral ankle sprain)