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Anthony J. Berni, MD Orthopedic Surgeon

Anthony J. Berni, MD Orthopedic Surgeon

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Knee

Knee Topics

Knee Anatomy

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.

Knee Pain

The knee is one of the largest joints in the body, formed by the lower end of the femur, upper end of the tibia and the patella or knee cap. Several ligaments and muscles attach to the bones of the knee joint to maintain normal motion of the joint. Special cartilaginous tissues known as menisci are placed between the two articular ends of the joint. These act as a cushion between the articular surfaces and absorb the shock during movement.

Anterior knee pain

Anterior knee pain is a characterized by a chronic pain over the front and center of the knee joint. It is common in athletes, active adolescents (especially girls) and overweight individuals. Anterior knee pain refers to a variety of conditions which include runner's knee or patellar tendinitis and chondromalacia of the patella. There is an inter-individual variation in the duration and presentation of pain

Runner’s Knee

Runner's knee, also called patellofemoral pain syndrome refers to pain under and around your kneecap. Runner’s knee includes a number of medical conditions such as anterior knee pain syndrome, patellofemoral malalignment, and chondromalacia patella that cause pain around the front of the knee. As the name suggests, runner’s knee is a common complaint among runners, jumpers, and other athletes such as skiers, cyclists, and soccer players.

Osgood Schlatters

Osgood-Schlatter disease refers to a condition of an overuse injury that occurs in the knee region of growing children and adolescents. This is caused by inflammation of the tendon located below the knee cap (patellar tendon). Children and adolescents who participate in sports such as soccer, gymnastics, basketball and distance running are at higher risk of this disease.

Chondromalacia patella

The patella, also called the kneecap is a small bone present on the front of your knee joint. The underside of the patella is covered by cartilage that allows smooth gliding of the knee with movement. Overuse or misalignment of the patella can cause wear and tear of the cartilage.

Jumpers knee

Jumper’s knee, also known as “patellar tendinitis" is an inflammation of the patellar tendon that connects your kneecap (patella) to your shinbone. This tendon helps in extension of the lower leg.

Bursitis

A bursa is a small fluid-filled sac found between soft tissues and bones. It lubricates and acts as a cushion to decrease friction between bones when they move. Bursitis refers to the inflammation and swelling of the bursa. Inflammation of the bursa in front of the kneecap (patella) is known as kneecap bursitis or prepatellar bursitis.

Bakers Cyst

The knee consists of a fluid called synovial fluid, which reduces friction between the bones of the knee joint while you move your leg. Sometimes this fluid is produced in excess, resulting in its accumulation in the back of your knee. A Baker’s cyst or popliteal cyst is a fluid-filled swelling that develops into a lump behind the knee. This causes stiffness, tightness and pain behind your knee. It is commonly seen in women and people aged over 40 (although it can develop at any age).

Iliotibial Band Syndrome

Iliotibial band syndrome is an overuse injury resulting from the inflammation of iliotibial band. Iliotibial band is a tough group of fibers that begins at the iliac crest of hip and runs along the outside of the thigh, to get attached to the outer side of the shin bone just below the knee joint.

Osteochondritis Dissecans

Osteochondritis dissecans is a joint condition in which a piece of cartilage, along with a thin layer of the bone separates from the end of the bone because of inadequate blood supply. The separated fragments are sometimes called “joint mice”. These fragments may be localized, or may detach and fall into the joint space causing pain and joint instability.

Shin Splints

“Shin splints” is used to describe the pain and inflammation of the tendons, muscles and bone tissue around the tibia or shine bone (a large bone in the lower leg). It occurs as a result of vigorous physical activity such as exercise or sports. The condition is also referred to as medial tibial stress syndrome (MTSS).

Knee Injury

Pain, swelling and stiffness are the common symptoms of any damage or injury to the knee. If care is not taken during the initial phases of injury, it may lead to joint damage that may end up destroying your knee.

Unstable Knee

The knee joint is one of the largest joints in the body. This highly complex joint has several tissues supporting and stabilizing its movement:

Goosefoot Bursitis of The Knee

A bursa is a small fluid-filled sac found between soft tissues and bones. It lubricates and acts as a cushion to decrease friction between bones when they move. Bursitis refers to the inflammation and swelling of the bursa.

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.

Anterior Cruciate Ligament (ACL) Tears

The anterior cruciate ligament, or ACL, is one of the major ligaments of the knee that is located in the middle of the knee and runs from the femur (thigh bone) to the tibia (shin bone). It prevents the tibia from sliding out in front of the femur.

Medical Collateral Ligament Tears (MCL)

The medial collateral ligament (MCL) is the ligament that is located on the inner part of the knee joint. It runs from the femur (thighbone) to the top of the tibia (shinbone) and helps in stabilizing the knee.

MCL Sprain

The medial collateral ligament (MCL), a band of tissue present on the inside of your knee joint, connects your thigh bone and shin bone (bone of your lower leg). The MCL maintains the integrity of the knee joint and prevents it from bending inward.

Meniscal Tears

Meniscus tear is the commonest knee injury in athletes, especially those involved in contact sports. A suddenly bend or twist in your knee cause the meniscus to tear. This is a traumatic meniscus tear.

Ligament Injuries

The knee is a complex joint which consists of bone, cartilage, ligaments and tendons that make joint movements easy and at the same time more susceptible to various kinds of injuries.

Knee Arthritis

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.

Patellar Dislocation

Patella (knee cap) is a protective bone attached to the quadriceps muscles of the thigh by quadriceps tendon. Patella attaches with the femur bone and forms a patellofemoral joint. Patella is protected by a ligament which secures the kneecap from gliding out and is called as medial patellofemoral ligament (MPFL).

Patellar Tendinitis

Patellar tendinitis, also known as “jumper’s knee” is an inflammation of the patellar tendon that connects your kneecap (patella) to your shinbone. This tendon helps in extension of the lower leg.

Posterior Cruciate Ligament Injuries

Posterior cruciate ligament (PCL), one of four major ligaments of the knee is situated at the back of the knee. It connects the thighbone (femur) to the shinbone (tibia). The PCL limits the backward motion of the shinbone.

Chondral (Articular Cartilage) Defects

Articular or hyaline cartilage is the tissue lining the surface of the two bones in the knee joint. Cartilage helps the bones move smoothly against each other and can withstand the weight of the body during activities such as running and jumping.

Patellar Instability

Patellar (knee cap) instability results from one or more dislocations or partial dislocations (subluxations). Patella is the small piece of bone in front of the knee that slides up and down the femoral groove (groove in the femur bone) during bending and stretching movements.

Patellofemoral Instability (Knee)

Patellofemoral Instability results from one or more dislocations or partial dislocations, also called subluxations. This misalignment can damage the underlying soft structures such as muscles and ligaments that hold the knee in place. Once damaged, these soft structures are unable to keep the patella (knee cap) in position.

Patellofemoral Dislocation

Patella (knee cap) is a protective bone attached to the quadriceps muscles of the thigh by quadriceps tendon. Patella attaches with the femur bone and forms a patellofemoral joint. Patella is protected by a ligament which secures the kneecap from gliding out and is called as medial patellofemoral ligament (MPFL).

Patella Fracture

The knee cap or patella is the largest sesamoid bone in the body and one of the components of the knee joint, present at the front of the knee. The undersurface of the kneecap and the lower end of the femur are coated with articular cartilage, which helps in smooth movement of the knee joint.

Recurrent Patella Dislocation

The patella (knee cap) is a small bone that shields your knee joint. It is found in front of your knee, in a groove called the trochlear groove that sits at the junction of the femur (thighbone) and tibia (shinbone). Articular cartilage present below the patella and end of the femur cushion and help the bones glide smoothly over each other when the legs move. This joint is stabilized and supported by a network of soft tissues.

Quadriceps Tendon Rupture

Quadriceps tendon is a thick tissue located at the top of the kneecap. The quadriceps tendon works together with the quadriceps muscles to allow us to straighten our leg. The quadriceps muscles are the muscles located in front of the thigh.

Patella Tendon Rupture or Tear

Patella tendon rupture is the rupture of the tendon that connects the patella (knee cap) to the top portion of the tibia (shin bone). The patellar tendon works together with the quadriceps muscle and the quadriceps tendon to allow your knee to straighten out.

Lateral Meniscus Syndrome

The knee joint is formed by the union of two bones, namely the femur (thigh bone) and the tibia (lower leg bone). At the junction of these two bones is a cartilage called the meniscus, which acts as a shock absorber. There are two menisci – the lateral and medial menisci.

Medial Meniscus Syndrome

Of the menisci within the knee, it is the medial that is more easily injured. Differences in the anatomical attachments of the medial meniscus compared to the lateral mean that the medial meniscus becomes distorted during combined flexion and rotation movements in a manner not experienced on the lateral side.

Osteonecrosis of The Knee

Osteonecrosis is a condition in which death of a section of bone occurs because of lack of blood supply to it. It is one of the most common causes of knee pain in older women. Women over the age of 60 years of age are commonly affected, three times more often than men.

Knee Angular Deformities (Knock Knees and Bow Legs)

Angular deformities of the knee are common during childhood and usually are variations in the normal growth pattern. Angular deformity of the knee is a part of normal growth and development during early childhood. Physiologic angular deformities vary with age as:

Pharmacological

The knee is a complex joint which consists of bone, cartilage, ligaments and tendons that make joint movements easy and at the same time more susceptible to various kinds of injuries. Knee problems may arise if any of these structures get injured by overuse or suddenly during sports activities.

Platelet-Rich Plasma (PRP) Injection

Platelet-rich plasma (PRP) is a newer modality of treatment for the management of many orthopedic conditions including sport injuries. RBC (red blood cells), WBC (white blood cells), plasma, and platelets are the major components of blood.

Viscosupplementation (Synvisc) Injection

Viscosupplementation refers to the injection of a hyaluronan preparation into the joint. Hyaluronan is a natural substance present in the joint fluid that assists in lubrication. It allows smooth movement of the cartilage covered articulating surfaces of the joint.

Cortisone Injection

Cortisone is a corticosteroid released by the adrenal gland in response to stress and is a potent anti-inflammatory agent. Artificial preparations containing cortisone are injected directly into the affected joint to relieve pain and reduce inflammation.

Physiotherapy

Physiotherapy or physical therapy is an exercise program that helps you to improve movement, relieve pain, encourage blood flow for faster healing, and restore your physical function and fitness level. The main aim of physical therapy is to make your daily activities such as walking, getting in and out of bed, or climbing stairs easier.

Knee Osteotomy

Knee Osteotomy is a surgical procedure in which the upper shinbone (tibia) or lower thighbone (femur) is cut and realigned. It is usually performed in arthritic conditions affecting only one side of your knee and the aim is to take pressure off the damaged area and shift it to the other side of your knee with healthy cartilage.

High Tibial Osteotomy

High tibial osteotomy is a surgical procedure performed to relieve pressure on the damaged site of an arthritic knee joint. It is usually performed in arthritic conditions affecting only one side of your knee and the aim is to take pressure off the damaged area and shift it to the other side of your knee with healthy cartilage.

Tibial Tubercle Osteotomy

Tibial tubercle osteotomy is a surgical procedure which is performed along with other procedures to treat patellar instability, patellofemoral pain, and osteoarthritis. This is a quite safe procedure and provides excellent access and surgical exposure during a difficult primary or revision total knee arthroplasty.

Unicompartmental 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

Patellofemoral Knee Replacement

Patellofemoral Knee Replacement surgery may be recommended by your surgeon if you have osteoarthritis contained to the patellofemoral compartment and you have not obtained adequate relief with conservative treatment options.

What’s New in Knee Replacement?

For a patient considering knee replacement surgery, there are new developments under study which can help enhance their quality of life. These include:

Total Knee Replacement

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).

Partial 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

Custom Knee Replacement Surgery

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).

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.

Arthroscopic Reconstruction of The Knee for Ligament Injuries

The anterior cruciate ligament is one of the major stabilizing ligaments in the knee. It is a strong rope like structure located in the center of the knee running from the femur to the tibia. When this ligament tears unfortunately, it does not heal and often leads to the feeling of instability in the knee.

ACL Reconstruction (Patellar & Hamstring Tendon)

Anterior cruciate ligament (ACL) reconstruction patellar tendon is a surgical procedure that replaces the injured ACL with a patellar tendon. Anterior cruciate ligament is one of the four

Outpatient Total Knee Replacement

Total knee replacement is the surgical treatment for knee arthritis, where the damaged knee is removed and replaced with an artificial knee implant. Traditionally performed as an inpatient procedure, total knee replacement surgery is now being conducted on an outpatient basis, allowing patients to go home the same day of the surgery.

Tricompartmental Knee Replacement

Tricompartmental 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.

After Knee Replacement

Knee replacement is a surgery performed to replace parts of a diseased knee joint with an artificial prosthesis. The goal of knee replacement is to eliminate pain and return you to your normal activities. You can help in recovery and improve the outcomes of the procedure by following certain precautions and changing the way you carry out your daily activities.

Signature Knees

The knee joint, made up of the ends of the femur (thigh bone) and tibia (shin bone) is cushioned by a spongy tissue called cartilage. Damage and wear and tear of the cartilage causes painful rubbing of the joint bones, leading to disability.

iTotal Customized Knee Replacement System

The ConforMIS iTotal CR is an individualized patient specific implant for replacement of all the three compartments of the knee. It is thus most appropriate for patients with knee arthritis and knee damage requiring implant for not one or two but all the three compartments of the knee.

Custom-fitted Total Knee Arthroplasty

Custom fitted total knee arthroplasty is a newer technology in total knee replacement surgery. It is an advanced procedure using an individualized patient-specific knee implant for replacement of all three components of the knee.

Knee Implants

Knee implants are artificial devices that form the essential parts of the knee during a knee replacement surgery. The knee implants vary by size, shape, and material. Implants are made of biocompatible materials that are accepted by the body without producing any rejection response.

Patellar Tendon Repair

Patella tendon rupture is the rupture of the tendon that connects the patella (knee cap) to the top portion of the tibia (shin bone). The patellar tendon works together with the quadriceps muscle and the quadriceps tendon to allow your knee to straighten out.

Knee Ligament Reconstruction

Anterior cruciate ligament (ACL) reconstruction patellar tendon is a surgical procedure that replaces the injured ACL with a patellar tendon. Anterior cruciate ligament is one of the four

Cartilage Replacement

Cartilage replacement is a surgical procedure performed to replace the worn out cartilage with the new cartilage. It is usually performed to treat patients with small areas of cartilage damage usually caused by sports or traumatic injuries. It is not indicated for those patients who have advanced arthritis of knee.

Cartilage Repair & Transplantation

Articular Cartilage is the white tissue lining the end of bones where these bones connect to form joints. Cartilage acts as cushioning material and helps in smooth gliding of bones during movement. An injury to the joint may damage this cartilage which cannot repair on its own.

Bicompartmental Knee Resurfacing

The knee can be divided into three compartments: Patellofemoral, the compartment on the front of the knee which contains the knee cap, medial compartment, the compartment on the inside of the knee, and lateral compartment which is the area on the outside of the knee joint.

Partial Knee Resurfacing

Partial knee replacement is an alternative to total knee replacement in patients with arthritis on only one side of the knee. Partial knee replacement is a surgical procedure which involves resurfacing and replacement of only the diseased surface of the joint instead of the entire joint.

Subchondroplasty

The knee is a complex joint which consists of bone, cartilage, ligaments and tendons that make joint movements easy.  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. 

Partial Meniscectomy

Partial meniscectomy is a surgical procedure to remove the torn portion of the meniscus from the knee joint. Meniscus is the C-shaped cartilage located in the knee that lubricates the knee joint, acts as shock-absorber, and controls the flexion and extension of joint. Meniscal tears can occur at any age, but are more common in athletes

Meniscal Surgery

Meniscus tear is the commonest knee injury in athletes, especially those involved in contact sports. A suddenly bend or twist in your knee cause the meniscus to tear. This is a traumatic meniscus tear. Elderly people are more prone to degenerative meniscal tears as the cartilage wears out and weakens with age. The two wedge-shape cartilage pieces present between the thighbone and the shinbone are called meniscus. They stabilize the knee joint and act as “shock absorbers”.

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  • J Berni MD Orthopedic Surgeon American Acaadmey Of Orthopaedic Surgeon
  • American board Of Orthopaedic Surgery
  • J Berni MD Orthopedic Surgeon Saint Louis University
  • J Berni MD Orthopedic Surgeon University Of Missouri-Health