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