Transcript The Knee
The Knee
ANATOMY
The Knee
Bones (4)
Femur
Tibia
Fibula
Patella
Patella
Sesamoid bone – sits inside the
quadriceps/patellar tendon
Patellar tendon attaches to the tibial
tuberosity
Patella rides in a groove on the femur
The Knee
Joints (2)
Femur and tibia
Motions: flexion and extension
Patellofemoral
Patella sits on the femur in quadriceps tendon
Ligaments
Cruciates (2)
Short, strong ligaments inside the knee joint
Cross each other and form an ‘x’
Cruciate means cross
Named for where they attach on the tibia
Functions
Provide anterior and posterior stability
Prevent rotation at knee
Ligaments
Cruciates
Anterior Cruciate Ligament (ACL)
Prevents anterior movement of tibia on femur
Ligaments
Cruciates
Posterior Cruciate Ligament (PCL)
Twice as strong as the ACL
Prevents posterior movement of the tibia on the femur
Ligaments
Collaterals
On sides of knee
Give side to side stability
Ligaments
Collaterals
Medial Collateral Ligament (MCL)
Goes from the femur to the tibia
Prevents valgus stress
Valgus stress: pushing knee from outside in
Ligaments
Collaterals
Lateral Collateral Ligament (LCL)
Goes from femur to the head of the fibula
Prevents varus stress
Varus Stress: Knee pushed from inside out
Meniscus
“Cartilage” of the knee
Sit on the tibia
Functions:
Deepens socket for the femur
Gives stability to the knee
Shock absorption
Meniscus
Medial
Larger and ‘c’ shaped
More firmly fixed to the tibia
Attached to tibia, MCL, and joint capsule
Lateral
Oval shaped
More freely movable
Muscles
Quadriceps femoris (Quad)
Four muscles on the anterior thigh
Rectus Femoris
Vastus Medialis
Vastus Intermedius
Vastus Lateralis
Function is to straighten/extend the knee
Patella sits inside the tendon that is formed by these
muscles
Muscles
Hamstrings
Three muscles on the posterior thigh
Biceps Femoris
Semitendinosus
Semimembranosus
Function is to flex/bend the knee
Also function to extend the hip
INJURIES
MCL Sprain
Cause
Signs and Symptoms
Blow to the lateral side of the knee
Rotation to knee
MCL is tender to touch
Hurts to have knee totally straight
Positive Valgus stress test
Will “give out” if 2nd or 3rd degree
Treatment
RICE immediately
Immobilizer/brace for 2-6 weeks
LCL Sprain
Cause
Signs and Symptoms
Injured by a blow to the medial side of the knee
Not a very common injury
Pain and tenderness over LCL
Positive Varus Stress test
Treatment
RICE immediately
Immobilizer/brace for 2-6 weeks
PCL Sprain
Injured by:
Signs and Symptoms
Blow forcing tibia back
Leg is bent and it is hit on tibial tuberosity
Hyperextension
Feel and hear pop in the back of the knee
Positive Posterior Drawer Test
Care
RICE immediately and rehab
Some athletes can participate without a PCL
ACL Sprain
Causes
Signs and Symptoms
Plant and cut in opposite direction
Hyperextension
Blow to the lateral side
Feel and hear a pop
Immediate swelling
Major pain and then pain can subside
Positive Lachman’s and Anterior Drawer Test
Feels like it will give out if standing on it
Treatment
RICE immediately, Crutches
Needs surgery to repair – out 6 months
Meniscus
Injured when they get trapped/pinched between the bones
Medial Meniscus injured more often than Lateral Mensicus
Cause
Sign and Symptoms
Planting foot and cutting in opposite direction, knee is flexed
Symptoms can come about 48-72 hours later
Swelling, giving out, knee locks up, clicking
Pain with squatting
Treatment
RICE
If locked, to MD right away
Needs Arthroscopic surgery
The Unhappy Triad
Injury to the ACL,
MCL and Medial
Meniscus
Injured all at once
Cause: planting foot
and cutting/twisting
Patellar Tendinitis
Also known as Jumper’s Knee
Cause
Signs and Symptoms
Running and jumping sports
Poor flexibility
Sorest at warm-up and cool down
May have crepitus
Tender over patellar tendon
Treatment
Rest – decrease pounding activity
Anti-inflammatory meds
Ice/Ice Massage
Heat
Patellar Tendon Strap
Osgood-Schlatter
Insertion of the patellar tendon on the tibial tuberosity
gets stressed and pulls away from its insertion site
Cause
Signs and Symptoms
From repeated jumping
Common in adolescents
Pain will be right on the tibial tuberosity
Tibial tuberosity will become much more prominent
Treatment
Much the same as patellar tendonitis
Dislocation/Subluxation of Patella
Dislocated patella
Goes out and stays out
Victim will be found with knee bent –
patella will be on lateral side of knee
Extending the knee will reduce the patella
Subluxed patella
Dislocates and reduces itself quickly
More common
Signs: History of patella problems, sore
over the medial aspect of the patella
Dislocation/Subluxation of Patella
Cause
Due to quad contracting and/or twisting of the
knee
Once it happens, it is more likely to happen again
More prone if you are
Female
Have a weak vastus medialis
Treatment
Referral to MD
RICE immediately
Will usually require rehab and immobilization
Chondromalacia
Cause
Signs and Symptoms
Degenerative process where the articular cartilage
under the patella softens and then wears away
Patella may not track well in the groove
Poor flexibility
Pain and grinding sensation under the patella
Aching pain after activity
Treatment
Ice
Increase flexibility of leg muscles
May have to decrease activity while inflamed.
Pre-Patellar Bursitis
Cause
Signs and Symptoms
Direct hit to knee
Kneeling
Increased swelling right on top of knee
Treatment
Ice
Compression
Eliminate the cause
Iliotibial Band Friction Syndrome
Cause
Signs and Symptoms
Running and cycling
Malalignment/tightness of lower extremities
Pain on lateral side of knee – above joint line
Pain increase with activity
Treatment
Stretch IT Band
Ice or heat
Fix biomechanical problems