Knee Resection: What It Is, Why It's Done, and What to Expect

What is a Knee Resection?

A knee resection is a surgical procedure involving the removal of damaged or diseased bone and cartilage from the knee joint, typically performed to alleviate pain and restore function, most commonly as part of a total or partial knee replacement.

Understanding Knee Resection

The term "resection" in a surgical context refers to the removal of part of an organ, bone, or other body structure. When applied to the knee, it specifically means the precise removal of compromised bone and cartilage surfaces that form the knee joint. This procedure is not performed in isolation but is a critical initial step in several reconstructive knee surgeries, most notably total knee arthroplasty (TKA) and partial knee arthroplasty (PKA). The goal is to prepare the joint surfaces to receive prosthetic implants, which will then articulate smoothly, mimicking the natural joint.

Why is a Knee Resection Performed?

Knee resection is indicated when conservative treatments (such as medication, physical therapy, injections, or lifestyle modifications) have failed to provide adequate relief for severe knee joint pathology. The primary conditions necessitating this procedure include:

• Severe Osteoarthritis (OA): Often referred to as "wear-and-tear" arthritis, OA causes the protective cartilage on the ends of your bones to wear down over time, leading to bone-on-bone friction, pain, stiffness, and loss of function.
• Rheumatoid Arthritis (RA): An autoimmune disease that causes chronic inflammation, leading to cartilage damage, bone erosion, and joint deformity.
• Post-Traumatic Arthritis: Arthritis that develops after a significant knee injury, such as a fracture or ligament tear, leading to premature cartilage degradation.
• Bone Tumors: In rare cases, a malignant or aggressive benign tumor affecting the bone around the knee may require resection of the involved bone segment.
• Severe Knee Deformity: Conditions that cause significant misalignment of the knee joint, leading to uneven wear and pain.

Types of Knee Resection in Arthroplasty

The extent of the resection depends on the specific type of knee replacement being performed:

• Total Knee Arthroplasty (TKA): This is the most common form of knee resection. It involves the removal of the damaged surfaces of all three bones forming the knee joint: the end of the femur (thigh bone), the top of the tibia (shin bone), and often the back surface of the patella (kneecap). These resected surfaces are then replaced with metal and plastic prosthetic components.
• Partial Knee Arthroplasty (PKA) / Unicompartmental Knee Arthroplasty (UKA): If only one compartment of the knee (medial, lateral, or patellofemoral) is severely damaged, a partial resection may be performed. This involves removing only the affected bone and cartilage from that specific compartment, preserving the healthy bone, cartilage, and ligaments in the other compartments.

In cases of tumor resection, the amount of bone removed can be much more extensive and may require complex reconstructive techniques using bone grafts or custom prostheses.

The Surgical Procedure: What to Expect

A knee resection is performed in an operating room under general or regional anesthesia. While the exact steps vary, the general process involves:

• Incision: An incision is made over the front of the knee to expose the joint.
• Joint Exposure: The quadriceps muscle and patella are typically moved aside to fully visualize the damaged joint surfaces.
• Precise Bone Resection: Specialized instruments, guides, and often computer navigation or robotic assistance are used to precisely measure and remove the damaged bone and cartilage from the femur, tibia, and/or patella. The goal is to create perfectly flat or angled surfaces that match the prosthetic components, ensuring proper alignment and stability.
• Trial Components: Trial components are often placed to verify fit, alignment, and range of motion before the permanent implants are cemented or press-fit into place.
• Implant Placement: The permanent metal and plastic prosthetic components are secured to the resected bone surfaces.
• Closure: The knee joint is thoroughly irrigated, and the incision is closed with sutures or staples.

Post-Operative Recovery and Rehabilitation

Recovery after a knee resection, particularly as part of an arthroplasty, is a critical phase for optimal outcomes.

• Immediate Post-Op: Patients typically begin moving the knee within hours of surgery, often with the assistance of a continuous passive motion (CPM) machine or a physical therapist.
• Pain Management: Pain is managed with medication, and early mobilization helps reduce stiffness and improve circulation.
• Physical Therapy: This is paramount. A structured physical therapy program will focus on:
  • Restoring Range of Motion (ROM): Exercises to regain full flexion and extension of the knee.
  • Strengthening: Exercises to rebuild the strength of the quadriceps, hamstrings, and gluteal muscles, which are crucial for knee stability and function.
  • Gait Training: Learning to walk properly with the new joint, often initially with assistive devices like crutches or a walker.
  • Balance and Proprioception: Exercises to improve balance and the body's awareness of the knee's position in space.
• Timeline: While individual recovery varies, most patients can expect to regain significant function within 3-6 months, with continued improvements for up to a year or more. Adherence to the physical therapy program is crucial for maximizing recovery.

Potential Risks and Complications

As with any major surgery, knee resection carries potential risks, including:

• Infection
• Blood clots (deep vein thrombosis, pulmonary embolism)
• Nerve or blood vessel damage
• Stiffness or limited range of motion
• Persistent pain
• Implant loosening or wear over time
• Fracture during or after surgery

These risks are carefully discussed with patients by their surgical team.

Outlook and Long-Term Considerations

For suitable candidates, knee resection as part of an arthroplasty procedure is highly successful in relieving pain, correcting deformity, and restoring mobility and quality of life. Most knee replacements last for 15-20 years or more, though this can vary based on individual activity levels and implant type.

• Activity Modifications: While patients can return to many activities, high-impact sports (e.g., running, jumping, contact sports) are generally discouraged to protect the longevity of the implant. Low-impact activities like swimming, cycling, walking, and golf are highly encouraged.
• Follow-Up Care: Regular follow-up appointments with the orthopedic surgeon are important to monitor the health of the joint replacement.

Conclusion

A knee resection is a fundamental and precise surgical step, primarily within knee replacement procedures, designed to remove diseased bone and cartilage from the knee joint. It is a critical intervention for individuals suffering from severe knee pain and dysfunction due to conditions like advanced arthritis. While a significant surgery, advancements in surgical techniques and post-operative rehabilitation have made knee resection, as part of arthroplasty, one of the most successful and life-changing orthopedic procedures available, enabling patients to return to a more active and pain-free lifestyle.