ACL Injuries: The anterior cruciate ligament in the knee joins the upper and lower leg bones. When it tears, the knee becomes less stable, and the bones in the knee can rub together, causing pain and degeneration. ACL injuries most often happen when the knee twists or bends to the side—or if a lot of abnormal movements happen at the same time.
Bursitis: Sacs called bursae live between the bone and muscle in your joints. These bursae are filled with fluid, which the body uses to keep the joint lubricated. Years of minor impact on the joint, a sudden injury, or stress from other conditions like arthritis can irritate the bursae, causing intense pain.
Cartilage Problems: Cartilage covers the ends of the bones in a healthy joint. When it tears or wears away, it can cause a lot of pain in a joint. Tearing can leave tiny fragments of cartilage to get wedged between the bones in the joint, locking the joint in place.
Dislocations: Any joint in the body can slip out of its correct position on impact. This painful condition is considered a medical emergency, especially if you can't tell if the bones in your knee are dislocated or broken.
Fractures: All broken bones are known as fractures. Your break can be simple or complex—and serious fractures can affect the tissue surrounding the bone, causing infection or damage to blood vessels. If you believe you have a fracture, go directly to the Emergency Department.
Jumper's Knee (Patellar Tendinitis): The patellar tendon connects the kneecap to the shinbone. This tendon allows you to extend your knee to run, jump, and kick. If you have a daily workout that includes a lot of jumping and running, you may feel pain at the beginning of your workout that subsides as you get warmed up. Don't be fooled—the pain can get worse until it restricts your ability to move your knee.
LCL Injury: The lateral collateral ligament is on the outside of the knee, where it helps keep the knee stable. If your knee gets pushed hard from the inside, it can stress or even tear the LCL.
MCL Injury: The medial collateral ligament is on the inside of the knee, where it keeps the shinbone in place. Pressure on the outside of the knee—in an accident or a football game, for example—can cause the MCL to stretch or tear.
Meniscus Injury: The two menisci in each knee keep the knee stable and act as a cushion around the knee. A sudden turn or twist can tear one of these discs. A minor or moderate tear will heal with rest in two weeks or so, while a severe tear can make your knee lock. Fixing a severe tear may require surgery.
Osgood-Schlatter Disease: Pain and swelling just below the kneecap may be a sign of this disease. The swelling occurs at the spot where the kneecap attaches to the patellar tendon, which attaches the kneecap to the shinbone. When there is too much stress on knee muscles, you can develop this condition. The pain can be severe enough to make it difficult to walk.
Osteoarthritis: There are many types of arthritis, but they all create pain and swelling in the joint. The most common form is osteoarthritis, caused by a breakdown of cartilage—the rubbery material that covers the ends of the bones in healthy joints. When the cartilage tears or wears away, the contact between the bones can be very painful. Surgery—including knee replacement—is often needed to remedy this.
Patellar Tracking Disorder: If you can feel your kneecap slipping, catching, or grinding when you bend your knee, you may have this disorder. The kneecap literally shifts out of place when you bend, and you may feel as if your knee can't support your weight.
PCL Injury: The posterior cruciate ligament works with the ACL (see above) to connect the thigh bone with the shin bone in the lower leg. An injury to either of these two ligaments can have a major impact on your ability to walk, maintain your workouts, or play a sport.
Runner's Knee (Patellofemoral Pain Syndrome): When you have pain in the front of the knee, you may have a condition caused by overuse or injury. This discomfort often comes from running, squatting, and jumping. You may have knee buckling—your knee may suddenly give way under your normal body weight.
Sprains and Strains: A misstep on the stairs, an unseen obstacle that causes you to trip, or any number of other minor accidents can result in all kinds of injuries to your body's soft tissue—ligaments, tendons, and muscles. Sprained knees are injuries to the ligaments. Strains—most often in a leg or foot—occur when you injure a muscle or a tendon. UR Medicine's Orthopaedics Urgent Care Clinic is ready to help patients with sprains and strains.
Synovial Problems: Synovium is part of the most flexible joints in the body. It's a layer of soft tissue that changes shape as you move, allowing your joints to bend and maneuver. It also brings nutrients to the cartilage in the joint. When the synovium is irritated, it becomes thick, cutting off nutrients to the cartilage. This happens in patients with rheumatoid arthritis, lupus, and a number of other systemic illnesses.
Tendinitis: Swelling, pain, redness, and heat from an injury are all symptoms of tendinitis. The pain and irritation come from a series of small stresses to a tendon. Runners, aerobic dancers, soccer and basketball players, and others who are on their feet a great deal get tendinitis in their legs and feet.
Unstable Kneecap: A sudden blow to the knee can pop it out of line, dislocating your knee. When this happens, the knee buckles under your weight. The kneecap can slip sideways, and it will hurt whether you put weight on it or sit still. Swelling, cracking, and stiffness are all symptoms of this emergency medical condition.