Knee Injury Intro - Is written to give a general amount of information about the knee, not intended to diagnosis any injury, please see your professional for diagnostic support.


The knee is a highly susceptible joint for injury. The knees position is manly influenced by the ankle and hip joints and there relative positions influence the length muscles that cross and secure the knee. Soft tissues like ligaments, tendons and a joint capsule are likely places of injury. The most susceptible place for injury is more dependent on the population and the sort are activity they are involved in. Men, women and chronological age are all important factors in determining incidents of injury. The Knee is not a true hinge joint but rather has a small rotary or unlocking mechanism. The knee locks in the straight position and unlocks when straightening and the femur has an internal rotation to lock the tibia and femur. As a Synovial joint there is joint fluid between the articulating bones wrapped and sealed in connective tissue pouch.


Common Structures


Bones- Pelvis (Illium, Pubic, Ischial Tuberosity), Femur, Patella, Tibia, Fibula


Ligaments- ACL, PCL, MCL, LCL, Joint Capsule

Muscles- Quadriceps (4), Hamstrings (4), Sartorius, Gracillus, Illio-Tibial Band with TFL Inside, Gastrocnemius, Popliteus, Plantarus ?

Cartilage and Boney Issues


Fractures at and around the knee are possible, the medial and lateral epicondyles can become damaged as well as fracture or subluxation (dislocation) of the fibular head are common boney issues as well as Fracture of patella are all possible but unlikely. An X-Ray can be diagnostic; revealing information about joint(s) locations indicating laxity or rupture of ligaments or to locate fractures.

Meniscal Tears: The meniscus are semi lunar cartilage located on the top of the tibia to which the femoral epicondyles pivot on and buffer forces between the femur and tibia. It can be one of the longest and most difficult rehab. The PCL connects up with the medial meniscus making for a possible bi or triad of problems.

Common Soft Tissue Injuries of the Knee

Anterior Cruciate Ligament Tear/Strain The ACL Tear is one of the more common knee injuries and 3x’s more likely to occur in women. The ACL injury typically occurs when the tibia is externally rotated with a valgus load (knock need) at the knee.  Or a skiers fall backwards in which the tibia is locked in place and as your knee flexes the femur unlocks and rotates internally creating the femoral rotation.

LCL-Lateral Collateral Ligament Tear/Strain: Varus Load is applied to the knee with the foot planted. In a contact situation this would be hit from the inside of the knee outward, non-contact situation might be getting pulled sideways by a dog on a leash.

MCL - Medial Collateral Tear/Strain: A Valgus Load is applied to the fibular side of the knee with the foot planted.

PCL - Posterior Cruciate Ligament Tear/Strain is common with a blow to the anterior part of the tibia. Pushing the tibia posterior of the joint center. Slamming knees on ground in bent position, or seated when knees collide with consul of car when in collisions.


Extensor Mechanism Problems


Bursitis- Many of the surfaces between bones and tendons are lubricated by pads of connective tissue called bursa. Very often these can become inflamed and irritated with exercise or sport.  Some of the commonly irritated bursa around the knee are: IT-Band Bursa located between the IT Band and lateral epicondyle/lateral quadriceps, Pes Anserine bursa inside the medial aspect of knee, prepatella Bursa under the quadriceps tendon.

Illiotibial Band Syndrome is inflation of the IT band, by repeated rubbing over the lateral epicondyle. Is commonly found in runners and cyclists.

Osgood-Schlatter Disease is a growth of the tibia tuberosity where the patella femoral tendon/ligament attaches.

Patellar Subluxation/Dislocation when the patella dislocates from its patellar groove.

Patellar/Quadriceps: Tendonitis/Rupture: is inflammation of the patellar tendon or tearing respectively.

Patello-Femoral Syndrome or pain is one of the most common disorders in the lower leg, it is a wearing down of the articular cartilage located n the back of the patella term should only be used after arthroscopic diagnosis of cartilage.

Popliteus Tendonitis is inflmation of Poplitius a small knee flexor located in the popliteal space located on the back of the knee.

TSS - Tibia Stress Syndrome is pain in the tibia located posterior and medial to the joint center. Often seen in runners, once was defined as a tightening of the deep facial attachments due to chronic loading, now also being defined as lower regional bone mineral density. This sort of disorder is found heavily in army recruits when an increase in intensity and volume of marching and running activities.