Knee Conditions

The ACL is one of four major ligaments in your knee. It runs diagonally through the middle of the joint and acts like a seatbelt — keeping your shinbone from sliding too far forward and preventing your knee from rotating in ways it shouldn't. ACL tears are one of the most common sports injuries, affecting roughly 200,000 Americans each year.

Your knee has two menisci — C-shaped pads of rubbery cartilage that sit between your thighbone and shinbone. They act as shock absorbers, distribute your body weight, and help keep the knee stable. A meniscus tear is one of the most common knee injuries and can happen to anyone, from young athletes to older adults going about daily life.

The PCL is the strongest ligament in the knee, running behind the ACL. Its job is to prevent the shinbone from sliding too far backward. PCL injuries are less common than ACL tears and are often caused by a direct blow to the front of the knee — like hitting the dashboard in a car accident or falling on a bent knee. Many PCL injuries heal without surgery, but severe tears can cause lasting instability.

The MCL (medial collateral ligament) is on the inside of your knee; the LCL (lateral collateral ligament) is on the outside. Together they prevent the knee from bending sideways. MCL injuries are among the most common knee injuries in contact sports. LCL injuries are less common but can be more complex when part of the posterolateral corner of the knee is involved.

The patella (kneecap) sits in a groove at the front of your knee and glides smoothly as you bend and straighten your leg. When it slips out of that groove — partially (subluxation) or completely (dislocation) — it's called patellar instability. This is most common in teenagers and young adults, especially females, and often recurs if not properly treated.

Cartilage is the smooth, slippery tissue that covers the ends of your bones inside the knee joint — it's what allows the joint to glide without friction. Unlike bone, cartilage has very little blood supply and a limited ability to heal on its own. When it's damaged — from an injury, repeated stress, or wear — it can cause significant pain and, if untreated, lead to early arthritis. Cartilage restoration is one of the most active areas of sports medicine surgery.

The patellar tendon connects your kneecap to your shinbone; the quadriceps tendon connects your quad muscles to the top of the kneecap. Together they form the "extensor mechanism" — what lets you straighten your knee. A complete tear of either tendon is a significant injury that almost always requires surgery to restore function. These are less common than ligament tears but are serious when they occur.

Osteoarthritis of the knee is the gradual wearing away of the cartilage that cushions the ends of the bones in your knee joint. Without this cushion, bone begins to rub on bone — causing pain, stiffness, and swelling. It's the most common form of arthritis, affecting over 32 million adults in the United States. While there is no cure, there are many effective treatments to reduce pain, improve function, and delay or avoid joint replacement surgery.

ACL revision surgery is one of the most technically demanding procedures in sports medicine. It is performed when a previously reconstructed ACL has re-torn, failed to heal, or was placed incorrectly during the original surgery. Revision cases are significantly more complex than primary ACL reconstruction — the failed graft must be removed, tunnel positions must be carefully assessed, bone loss from prior tunnels must be addressed, and a new graft must be selected and secured. When performed by an experienced surgeon, outcomes are good, but return-to-sport rates are lower than after primary ACL reconstruction and expectations should be carefully calibrated.

Meniscal allograft transplantation (MAT) is a procedure in which a donor meniscus (from a cadaver tissue bank) is transplanted into the knee to replace a meniscus that was previously removed. The meniscus is critical to knee health — it distributes load, absorbs shock, and protects cartilage. When it is completely or nearly completely removed (total meniscectomy), the knee is left vulnerable to accelerated arthritis. MAT is one of the most biologically sophisticated procedures in knee surgery and is reserved for a carefully selected group of young, active patients who meet strict criteria.

A knee osteotomy is a procedure that corrects abnormal leg alignment by cutting and repositioning the bone — shifting load away from the damaged side of the knee onto the healthier side. When arthritis or cartilage loss is isolated to one compartment of the knee, the underlying cause is often mechanical: the leg is not aligned properly, and over time, disproportionate load destroys that compartment. Rather than replacing the joint, an osteotomy realigns the bone to redistribute force and relieve symptoms — often preserving the knee for many years in active, younger patients.

A multiligament knee injury involves damage to two or more of the major knee ligaments — typically as the result of a high-energy event such as a contact sports collision, motor vehicle accident, or fall from height. These injuries can involve the ACL, PCL, MCL, LCL, and posterolateral corner in various combinations. They represent some of the most serious and complex injuries in all of orthopaedics, and in the most severe cases may involve a knee dislocation — a true surgical emergency that can threaten the blood supply to the leg.

The posterolateral corner (PLC) of the knee is an anatomically complex region made up of three primary structures: the fibular collateral ligament (FCL), the popliteus tendon, and the popliteofibular ligament. Together they resist varus stress, external rotation, and hyperextension. PLC injuries are frequently missed on initial evaluation — they are often dismissed as "LCL sprains" — but when combined with ACL or PCL tears, an unrecognized PLC injury is one of the most common reasons for ACL graft failure. Accurate diagnosis and surgical reconstruction of the PLC is essential for restoring full knee stability.

The posteromedial corner (PMC) of the knee is a group of structures on the inner-back aspect of the joint — including the posterior oblique ligament (POL), semimembranosus complex, and the posteromedial capsule. These structures work together to resist valgus stress (force pushing the knee inward) and rotational forces, particularly in flexion. PMC injuries are often lumped in with MCL injuries but are distinct and more complex. When combined with ACL or PCL tears, an unaddressed PMC injury dramatically increases joint instability and raises the risk of ligament reconstruction failure.

A tibial plateau fracture is a break in the upper portion of the shin bone (tibia) that forms part of the knee joint surface. This is a serious injury because it involves the weight-bearing cartilage surface of the knee — if the fracture is not properly reduced and stabilized, even small amounts of residual step-off or depression in the joint surface can lead to post-traumatic arthritis within a few years. These fractures frequently occur alongside meniscus tears, ligament injuries, and nerve damage, all of which must be carefully identified and managed.

A plica is a fold of the synovial membrane — the thin lining of the knee joint — that is a normal remnant of fetal knee development. Most people have plica folds and never know it. However, in some patients, a plica becomes thickened, inflamed, and symptomatic after overuse, injury, or repetitive bending activities. When this happens, it is called plica syndrome. It is one of the more commonly missed causes of anterior and medial knee pain in active patients, particularly runners and cyclists.