Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
Dr. Balentine received his undergraduate degree from McDaniel College in Westminster, Maryland. He attended medical school at the Philadelphia College of Osteopathic Medicine graduating in1983. He completed his internship at St. Joseph's Hospital in Philadelphia and his Emergency Medicine residency at Lincoln Medical and Mental Health Center in the Bronx, where he served as chief resident.
Knee pain is one of the most common musculoskeletal complaint that brings people to their doctor. With today's increasingly active society, the number of knee problems is increasing. Knee pain has a wide variety of causes and treatments.
Anatomy of the Knee
The knee joint's main function is to bend and straighten for moving the body. The knee is more than just a simple hinge. It also twists and rotates. In order to perform all of these actions and to support the entire body while doing so, the knee relies on a number of structures, including bones, ligaments, tendons, and cartilage.
The knee joint involves
The thighbone or femur comprises the top portion of the joint.
One of the bones in the lower leg
(calf area), the tibia, provides the bottom portion of the joint.
The kneecap or patella rides along the front of the femur.
The remaining bone in the calf, the fibula is not directly involved in the knee joint but is close to the outer portion of the joint (sometimes this bone is included in the knee joint and therefore the joint will be described as involving
Ligaments are fibrous bands that connect bones to each other.
The knee includes four important ligaments, all four of which connect the femur to the tibia:
The anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) provide front and back (anterior and posterior) and rotational stability to the knee.
The medial collateral ligament (MCL) and lateral collateral ligament (LCL) located along the inner (medial) and outer (lateral) sides of the knee provide medial and lateral stability to the knee.
Tendons are fibrous bands similar to ligaments.
Instead of connecting bones to other bones as ligaments do, tendons connect muscles to bones.
The two important tendons in the knee are (1) the quadriceps tendon
connecting the quadriceps muscle, which lies on the front of the thigh, to the patella and (2) the patellar tendon connecting the patella to the tibia (technically this is a ligament because it connects
The quadriceps and patellar tendons as well as the patella itself are sometimes called the extensor mechanism, and together with the quadriceps muscle they facilitate leg extension (straightening).
Cartilaginous structures called menisci (one is a meniscus) line the top of the tibia and lie between the tibia and the
two knuckles at the bottom of the femur (the femoral condyles).
Menisci provide both space and cushion for the knee joint.
Bursae (singular is bursa) are fluid-filled sacs that help to cushion the knee. The knee contains
three important groups of bursae.
The prepatellar bursa lies in front of the patella.
The anserine bursa is located on the inner side of the knee about 2 inches below the joint.
The infrapatellar bursa is located underneath the patella.
Problems not directly related to an injury or overuse may occur in or around the knee.
Osteoarthritis (degenerative joint disease) may cause knee pain that is worse in the morning and improves during the day. It often develops at the site of a previous injury. Other types of arthritis, such as rheumatoid arthritis, gout, and lupus, also can cause knee pain, swelling, and stiffness.
Osgood-Schlatter disease causes pain, swelling, and tenderness in the front of the knee below the kneecap. It is especially common in boys ages 11 to 15.
A popliteal (or Baker's) cyst causes swelling in the back of the knee.
Infection in the skin (cellulitis), joint (infectious arthritis), bone (osteomyelitis), or bursa (septic bursitis) can cause pain and decreased knee movement.
A problem elsewhere in the body, such as a pinched nerve or a problem in the hip, can sometimes cause knee pain.
Osteochondritis dissecans causes pain and decreased movement when a piece of bone or cartilage or both inside the knee joint loses blood supply and dies.