Knee surgery involves procedures performed to restore function or relieve pain caused by damage to the bones, cartilage, ligaments, or menisci within the knee joint. Intervention is typically needed due to acute trauma or progressive wear and tear. Acute injuries, such as a ligament tear or fracture, require immediate repair to restore stability. Degenerative conditions, like osteoarthritis, necessitate surgery after years of gradual deterioration, as the protective cartilage breaks down, leading to pain and stiffness.
Procedures Using Arthroscopy
Minimally invasive techniques address knee issues through small incisions, often leading to a faster recovery than open surgery. This approach uses an arthroscope, a thin instrument containing a camera and light source, allowing the surgeon to view the joint interior on a monitor. Small surgical instruments are inserted through separate incisions, minimizing trauma to surrounding tissue.
Arthroscopy is used for several procedures. A partial meniscectomy involves trimming away the torn portion of the meniscus, removing unstable tissue that causes locking or catching. A synovectomy is the removal of inflamed synovial tissue, which can be irritated by conditions like rheumatoid arthritis. Surgeons also use this technique to locate and remove loose bodies—small fragments of bone or cartilage floating within the joint space.
Surgeries for Structural Repair and Realignment
More complex procedures focus on reconstructing damaged structures or altering leg mechanics to preserve natural joint surfaces. Ligament reconstruction is a common major surgery, primarily for tears of the Anterior Cruciate Ligament (ACL) or Posterior Cruciate Ligament (PCL). These procedures replace the torn ligament with a tissue graft secured in tunnels drilled into the bone. The graft tissue is often an autograft, taken from the patient’s own body (such as the patellar or hamstring tendon), or an allograft, sourced from a deceased donor.
Unlike a meniscectomy, meniscus repair involves suturing a torn piece of cartilage back together to promote healing and preserve its shock-absorbing function. This technique is typically performed arthroscopically. Repair is generally reserved for tears in the outer, more vascularized “red zone” of the meniscus.
Another structural intervention is an osteotomy, which involves surgically cutting and reshaping the tibia (shin bone) or femur (thigh bone) near the knee joint. This procedure corrects angular deformities, such as bow-legged or knock-kneed alignment, that place excessive load on one side of the joint. By realigning the bone, the surgeon shifts the weight-bearing axis away from the damaged, arthritic compartment to a healthier area of the knee. The realignment is secured using plates and screws, aiming to relieve pain, improve function, and delay the need for total joint replacement, especially in younger, active patients.
Full and Partial Joint Replacement
When joint damage is too extensive for repair or realignment, the surgeon may recommend an arthroplasty, which is the replacement of the joint surfaces with artificial components. Total Knee Arthroplasty (TKA) is the most common form, involving the resurfacing of all three compartments of the knee: the femur, the tibia, and the patella. The damaged cartilage and bone are removed and replaced with metal alloy components and a durable plastic spacer that serves as the new gliding surface.
Partial Knee Arthroplasty (PKA), also called Unicondylar Knee Replacement, is a less invasive option reserved for patients whose arthritis is confined to only one of the three compartments, usually the medial side. This procedure replaces only the damaged surfaces while preserving the healthy cartilage, ligaments, and bone in the rest of the joint. PKA typically results in a smaller incision, less blood loss, and a quicker initial recovery compared to TKA, often leading to a feeling that is closer to a natural knee. However, PKA has a higher rate of requiring a future Revision Surgery. Revision Surgery is necessary when the original artificial components become loose, wear out over time, or become infected. This subsequent operation replaces the failed implants with new components.