Overview
Knee arthritis is the most common condition I treat in my practice. The most common form is osteoarthritis, or wear-and-tear arthritis. Arthritis results from the gradual breakdown of the articular cartilage that covers the ends of the bones. Under normal conditions this cartilage is extraordinarily smooth, creating less friction than ice sliding on ice. Once this surface begins to wear, increased friction causes one side of the joint to damage the other, creating a cycle of progressive degeneration.
Causes
Arthritis commonly develops with age but may also be influenced by genetics, previous injuries, excess body weight, occupation, and repetitive loading over many years.
Symptoms
Early symptoms include pain, swelling during flare-ups, stiffness, loss of motion, and difficulty with walking, stairs, kneeling, or squatting. Mechanical symptoms may occur when arthritis is associated with meniscus tears or loose bodies.
Conservative Treatment
Treatment begins with activity modification, anti-inflammatory medications, physical therapy, cortisone injections, and viscosupplementation. When comparing cortisone and viscosupplementation, cortisone generally provides stronger, more predictable short-term relief, while viscosupplementation often provides longer-lasting improvement and maintenance for selected patients.
One of the most important concepts is that arthritis is usually managed, not cured. These treatments reduce inflammation and improve symptoms but do not reverse the underlying cartilage loss. Many younger patients are treated conservatively for years to delay joint replacement whenever possible.
Surgical Treatment
When conservative treatment no longer provides acceptable function or quality of life, knee arthroplasty becomes the definitive treatment. Depending on the pattern of arthritis, this may include a total knee arthroplasty, partial (unicompartmental) knee arthroplasty, or patellofemoral arthroplasty. I perform all of these procedures using a preoperative CT scan for planning, which provides the three-dimensional data required for MAKO robotic-assisted surgery.
Arthroplasty is typically performed as an outpatient procedure, with patients going home the same day. Patients begin full weight-bearing immediately using a walker or crutches and receive home health nursing and physical therapy during the first few weeks after surgery. Patients typically have their first postoperative follow-up visit three weeks after surgery. At that time, they transition to outpatient physical therapy. Early rehabilitation focuses first on restoring full knee extension, followed by swelling control and knee flexion.
Results
Most patients are getting around reasonably well by six weeks, are functioning well by three months, and continue to improve throughout the first year. Modern knee replacements commonly last more than 20 years and provide excellent pain relief while restoring function for normal daily activities and low-impact recreational activities.
Potential Complications
Potential complications include stiffness, implant loosening, and infection. Loss of knee extension is particularly important because it permanently affects gait and is nearly impossible to treat once it sets in. Flexion stiffness, on the other hand, may often be improved if recognized early.
Infection is the most serious complication following knee replacement. It typically develops months or even years after surgery rather than at the time of surgery. Bacteria circulating in the bloodstream can attach to the prosthesis and establish an infection around the implant. Maintaining good overall health and promptly treating infections elsewhere in the body, including dental infections, is important. Further surgery is required, along with prolonged antibiotic treatment, and this complication can seriously compromise the final result.