Knee

Terminology Tibial Tuberosity: Boney protrusion where the patellar tendon inserts. Femoral Condyles: Distal end of the femur. Intercondyler Notch: An indentation in the distal femur where the anterior cruciate descends. Quadriceps Femoris Muscle group: attach to the patella through the quadriceps tendon.

Terminology Pes Anserine:“foot of a bird”, the insertion of the semitendinosis, sartorius, and gracilis to the anteromedial tibia Unhappy Triad (Terrible Triad): Tearing of the anterior cruciate ligament, medial collateral ligament and the medial meniscus. Varus Stress: Stress applied to the medial aspect of the knee. Valgus Stress: Stress applied to the lateral aspect of the knee.

Terminology Direct trauma: A blow or fall on the knee. Indirect trauma: violent contracture of the quadriceps Distal pulses: pulses in the foot. The dorsalis pedis and the posterior tibial pulse. Chondromalacia: A degenerative condition in which there is a wearing away of the cartilage on posterior patella. Subchondral: Below the cartilage.

Bones Of The Knee Femur Tibia Fibula Patella Femur Patella Fibula

Condyles of the Knee Lateral Condyle Medial Condyle

Patellar Tendon Tuberosity

Cartilage known as Menisci

Cruciate ligaments form an “X” http://www.kneeguru.co.uk/KNEEnotes/cruciate-ligament http://www.kneeguru.co.uk/KNEEnotes/node/829

Primary and Secondary Motions of The Knee 1. Primary Motions Flexion Extension 2. Secondary Motions Internal Rotation External Rotation Gliding Motion (a little)

Quadriceps Strongest muscle group in the body Vastus Medialis Vastus Intermedius Vastus Lateralis Rectus Femoris Responsible for knee extension

Hamstrings Biceps Femoris (long and short head) Semimembranosus Semitendinosus Responsible for knee flexion

Bursa Fluid sac acting as a cushion and lubricant in areas of friction Suprapatellar - under patella (running) Perpatellar - on top of patella (direct blow) Anserine - below knee (running)

Medial Collateral Ligament Sprain MOI: occurs most often in violently adducted and internally rotated knees. Path: a tear or sprain in the MCL S/S: swelling, pain, loss of stability, popping noise, (+) valgus stress test on MCL (may vary depending on degree of injury) Tx: RICE, rehab-light weights, straight leg raises, whirl pool (if available), crutches for discomfort and degree of injury, MCL taping

Lateral Collateral Ligament Sprain MOI: blow to inside of the knee (varus force) Path: partial to complete tear of ligament S/S: pain on lateral side of knee, swelling, positive varus stress test Tx: RICE, crutches and referral to physician

Anterior Cruciate Ligament Sprain (ACL) MOI: twisting of the knee, hyperextension of the knee, forward movement of the tibia on the femur Path: Stretching or tearing of the ACL; secondary injuries: medial meniscus tear and medial collateral ligament sprain Terrible Triad: ACL pathology WITH secondary injuries S/S: A pop followed by immediate disability, pain, rapid swelling at the joint, feels like knee is coming apart Tx: RICE, crutches, refer to doctor.

Meniscus Tear MOI: sudden twisting and compression Path: tear of the meniscus S/S: locking, swelling, pain, giving way Tx: RICE, crutches, refer to doctor.

Patellar Subluxation or Dislocation MOI: athlete plants their foot and changes direction. Path: the quadriceps muscles attempt to pull in a straight line and in a result pulls the patella laterally.

Patellar Subluxation or Dislocation Cont. S&S: Complete loss of knee function; pain and swelling Tx: immobilize in the position it is in, place ice around the joint, see physician, use crutches.

Patellar Fractures MOI: caused by direct or indirect trauma. Forcible muscle contraction, falling, jumping, and running can also cause a fracture. Path: a severe pull of the patellar tendon against the femur when knee is semi flexed resulting in a fracture S/S: causes hemorrhage and joint effusion, resulting in generalized swelling. An indirect fracture causes capsular tearing, separation of bone. Tearing of the quadriceps tendon is also a sign. Direct fracture involves bone separation.

Patellar Fracture Cont. Tx: a cold wrap should be applied, followed by elastic compression wrap, splinting, crutches and Doctor referral.

Knee Dislocation The most Serious knee injury is the dislocation of the tibiofemoral joint. THIS IS AN EMERGENCY! http://emedicine.medscape.com/article/1250829-overview

Knee Dislocation Cont. MOI: Direct blow to the anterior proximal tibia, forceful twisting, lateral blow to the knee. S/S: Grossly displaced tibia, sever pain, swelling, and may have absence of distal pulses. Tx: Calm athlete down, splint, and immediate transport to the hospital. Check distal pulses.