The Knee

Bones Femur, tibia ,patella (sesamoid) Primary Movement at tibiofermoral Patella glides up and down on the front of Femur- patella femoral joint

Cartilage Ends of tibia and femur covered and cushioned by menisci which is tough cartilage tissue Stops bones from rubbing against each other & stabilizes joints Attached to the top of tibia C-shaped Only outer portion receives blood supply about 4/5 is avascular (no blood supply) That’s why surgery is need because tears cannot be healed by the body

Ligaments 4 Primary Ligaments (ACL,PCL,MCL,LCL) Medial Collateral ligament Lateral Collateral ligament Anterior Cruciate ligament Posterior Cruciate ligament

Muscles QUADRICEPS GROUP Primary Movement of Quads Vastus medialis Vastus intermedius Vastus lateralis Rectus fermoris Primary Movement of Quads Extension

Hamstring Group Biceps femoris (long and short head) Semimembranosus Semitendinosus Primary movement of hamstring is knee flexion

Accessory Muscles Sartorius Gracilis Gastrocnemius

Ligaments sprains are most common injuries Knee injuries Ligaments sprains are most common injuries

ACL-keeps tibia from moving forward on femur MOI: can be non contact (changing directions, twisting)or contact (direct blow to anterior or leg) HYPEREXTENSION C/O: pain, swelling, inability to straighten leg, popping, collapsing of knee Tx: RICE, refers to orthopedist for MRI, surgery/rehab Reconstructed arthroscopically by cadaever tendon, patellar tendon, or hamstring tendon Return to activities after surgery is 3-6 months; bracing optional

PCL-prevents posterior tibial movement on femur MOI: a fall when the bent knee bears full weight, forceful hyper flexed C/O: hearing a “pop” Tx.: refers to orthopedic, rehab program focusing on the ROM and quad strength; usually non-surgical

MCL- prevents valgus stress (knee bends inward MOI: blow to outside (lateral) knee C/O: medial joint pain, swelling determined by severity of sprain, discomfort, joint laxity (stretch ligaments ) Loss of ROM Tx: RICE, Rehab ,R/O meniscus injury; usually non- surgically

LCL-prevents varus stress (knee bends outward) MOI: blow to inside of knee (medial) C/O: decrease in ROM Rehab focus on lateral thigh and hamstring strengthening

Muscle and Tendon injuries

Quad and Hamstring Strain MOI: overuse Excessive force/stretching C/O pain/soreness Lack of ROM Tx: ice ,stim compression wrap for activities, stretch to the point of no pain

Patellar Tendinitis (jumpers Knee) MOI: excessive jumping C/O pain swelling Tx: ice patellar strap for counterforce

Bone Injuries

Patellar Femoral Syndrome (patellar tracking problems) MOI: patella not moving smoothly, weak quadriceps muscles C/O: pain around the knee discomfort Cartilage wears away from underside of patella known as chondromalacia Grinding senstation Tx: correct patellar tracking

Patella dislocation MOI: patella forced laterally. Occurs when knee is bent and twisted inward C/O: obvious deformity; pain Tx: Immobilize; reduce dislocation; rehab

Meniscal Injuries Meniscal tear can be on outer edge middle or inside edge or on the ends