Knee

Normal Anatomy of the Knee Joint

Normal Anatomy of the Knee Joint

The knee is made up of four bones. The femur or thighbone is the bone connecting the hip to the knee. The tibia or shinbone connects the knee to the ankle. The patella (kneecap) is the small bone in front of the knee and rides on the knee joint as the knee bends. The fibula is a shorter and thinner bone running parallel to the tibia on its outside. The joint acts like a hinge but with some rotation.

The knee is a synovial joint, which means it is lined by synovium. The synovium produces fluid lubricating and nourishing the inside of the joint. Articular cartilage is the smooth surfaces at the end of the femur and tibia. It is the damage to this surface which causes arthritis.

Femur

The femur (thighbone) is the largest and the strongest bone in the body. It is the weight bearing bone of the thigh. It provides attachment to most of the muscles of the knee.

Condyle

The two femoral condyles make up for the rounded end of the femur. Its smooth articular surface allows the femur to move easily over the tibial (shinbone) meniscus.

Tibia

The tibia (shinbone), the second largest bone in the body, is the weight bearing bone of the leg. The menisci incompletely cover the superior surface of the tibia where it articulates with the femur. The menisci act as shock absorbers, protecting the articular surface of the tibia as well as assisting in rotation of the knee.

Fibula

The fibula, although not a weight bearing bone, provides attachment sites for the Lateral collateral ligaments (LCL) and the biceps femoris tendon.

The articulation of the tibia and fibula also allows a slight degree of movement, providing an element of flexibility in response to the actions of muscles attaching to the fibula.

Patella

The patella (kneecap), attached to the quadriceps tendon above and the patellar ligament below, rests against the anterior articular surface of the lower end of the femur and protects the knee joint. The patella acts as a fulcrum for the quadriceps by holding the quadriceps tendon off the lower end of the femur.

Menisci

The medial and the lateral meniscus are thin C-shaped layers of fibrocartilage, incompletely covering the surface of the tibia where it articulates with the femur. The majority of the meniscus has no blood supply and for that reason, when damaged, the meniscus is unable to undergo the normal healing process that occurs in the rest of the body. The menisci act as shock absorbers, protecting the articular surface of the tibia as well as assisting in rotation of the knee. As secondary stabilizers, the intact menisci interact with the stabilizing function of the ligaments and are most effective when the surrounding ligaments are intact.

Anterior Cruciate Ligament (ACL)

The anterior cruciate ligament (ACL) is the major stabilizing ligament of the knee. The ACL is located in the center of the knee joint and runs from the femur (thigh bone) to the tibia (shin bone), through the center of the knee. The ACL prevents the femur from sliding backwards on the tibia (or the tibia sliding forwards on the femur). Together with the posterior cruciate ligament (PCL), ACL stabilizes the knee in a rotational fashion. Thus, if one of these ligaments is significantly damaged, the knee will be unstable when planting the foot of the injured extremity and pivoting, causing the knee to buckle and give way.

Posterior Cruciate Ligament (PCL)

Much less research has been done on the posterior cruciate ligament (PCL) because it is injured far less often than the ACL.

The PCL prevents the femur from moving too far forward over the tibia. The PCL is the knee's basic stabilizer and is almost twice as strong as the ACL. It provides a central axis about which the knee rotates.

Collateral Ligaments

Collateral Ligaments prevent hyperextension, adduction, and abduction

  • Superficial MCL (Medial Collateral Ligament) connects the medial epicondyle of the femur to the medial condyle of the tibia and resists valgus force
  • Deep MCL (Medial Collateral Ligament) connects the medial epicondyle of the femur with the medial meniscus
  • LCL (Lateral Collateral Ligament) entirely separate from the articular capsule, connects the lateral epicondyle of the femur to the head of the fibula and resists varus force

Conditions

Knee Fracture

Knee Fracture

A fracture is a condition in which there is break in the continuity of the bone. In younger individuals these fractures are caused from high energy injuries, as from a motor vehicle accident. In older people the most common cause is weak and fragile bone.

Knee Sprain

Knee Sprain

Knee sprain is a common injury that occurs from overstretching of the ligaments that support the knee joint. A knee sprain occurs when the knee ligaments are twisted or turned beyond its normal range causing the ligaments to tear.

Procedures

Knee Arthroscopy

Knee Arthroscopy

Knee Arthroscopy is a common surgical procedure performed using an arthroscope, a viewing instrument, to look into the knee joint to diagnose or treat a knee problem. It is a relatively safe procedure and a majority of the patient’s discharge from the hospital on the same day of surgery.

Total Knee Replacement TKR

Total Knee Replacement TKR

Total knee replacement, also called total knee arthroplasty, is a surgical procedure in which the worn out or damaged surfaces of the knee joint are removed and replaced with artificial parts. The knee is made up of the femur (thigh bone), the tibia (shin bone), and patella (kneecap).

Uni condylar Knee Replacement

Uni condylar Knee Replacement

Unicompartmental knee replacement is a minimally invasive surgery in which only the damaged compartment of the knee is replaced with an implant. It is also called a partial knee replacement. The knee can be divided into three compartments: patellofemoral, the compartment in front of the knee between the knee cap and thigh bone, medial compartment, on the inside portion of the knee, and lateral compartment which is the area on the outside portion of the knee joint.

 Revision Knee Replacement

Revision Knee Replacement

Revision knee replacement surgery involves replacing part or all of your previous knee prosthesis with a new prosthesis. Although total knee replacement surgery is successful, sometimes the procedure can fail due to various reasons and require a second revision surgery.

Robot-assisted Knee Replacement

Robot-assisted Knee Replacement

Robotic assisted partial knee surgery is an innovative alternative to the conventional surgical procedure in patients suffering from degenerative knee diseases such as osteoarthritis. It is performed using robotic-arm technology that allows the surgeon to precisely perform the surgery through a smaller incision as compared to traditional surgery.

Minimally Invasive Approaches to Knee

Minimally Invasive Approaches to Knee

Total knee replacement is a very successful surgical treatment for knee arthritis. Over the years, minimally invasive knee replacement surgical techniques have been developed to lessen tissue trauma and improve patient outcomes. This minimally invasive approach involves much smaller incisions than the usual 10-12 inch incisions used in the traditional knee replacement and spares the quadriceps muscle and tendon, which control bending of the knee, from being cut to access the knee joint.

Patello-femoral Knee Replacement

Patello-femoral Knee Replacement

Arthritis is a general term covering numerous conditions where the joint surface or cartilage wears out. The joint surface is covered by a smooth articular surface that allows pain free movement in the joint. This surface can wear out for a number of reasons; often the definite cause is not known.

Non-surgical Treatment of the Knee

Non-surgical Treatment of the Knee

Ultrasound is a common imaging technique that employs high frequency sound waves to create images of organs and other internal structures of the body. These images provide valuable information of underlying pathology of the tissues and assists with diagnosis and planning the treatment of a particular condition. Ultrasound provides a clear view of the organs, tendons, muscles or joints and any associated disorders.

Fracture Care

Fracture Care

Fractures that enter the knee joint may cause joint imperfections, irregular joint surfaces, and improper alignment in the legs. This can lead to as joint instability, arthritis, and loss of motion. These fractures are caused by stress or trauma or in a bone already compromised by disease, such as cancer or infection.

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