Knee Arthritis
What is knee arthritis and how does it occur?
In general, arthritis refers to progressive wear of the cartilage that coats the ends of the bone. Because cartilage does not have any nerve endings, but bone does, loss of this cartilage exposing the bone eventually causes pain. There are three main compartments in the knee, the medial compartment, lateral compartment, and the patellofemoral compartment. Knee arthritis can refer to any or all of these compartments.
While there are many causes of arthritis, the most common causes are Osteoarthritis and Rheumatoid Arthritis. Rheumatoid Arthritis is discussed in more detail elsewhere. Osteoarthritis is secondary to general wear and tear on the knee and generally can worsen with age. The knee is particularly susceptible to Osteoarthritis given the knee is a weight bearing joint. While Osteoarthritis is usually a progressive disease, knee Osteoarthritis can be accelerated following knee trauma.
Risk factors associated with knee arthritis include increased weight, previous trauma to the knee, history of Osteochondritis Dessicans, high impact sports (football, basketball, etc.), occupational habits (squatting, kneeling, climbing), genetic predisposition, and advanced age.
Symptoms:
Pain is the most common symptom and tends to gradually worsen over time. Pain, however, can suddenly appear and be severe. The joint may also become swollen and stiff, especially after activities and with weather changes (rain, cold, etc…). Everyday activities such as walking and using stairs can become painful as the arthritis worsens. Patients may furthermore develop mechanical symptoms (locking/buckling/catching) upon range of motion secondary to large osteophytes (abnormal pieces of bone) and loose pieces of bone and cartilage within the joint.
Diagnostic Testing:
X-rays are usually ordered to evaluate the joint space and look for any osteophytes and loose bodies within the joint. MRI may be ordered to further evaluate for loose pieces of bone or cartilage within the joint. It is important to note that the appearance of the joint does not necessarily correlate with symptom severity. Patients with an x-ray showing severe osteoarthritis may have minimal pain and vice versa.
Non-operative Treatment:
Nonoperative treatment is first-line for knee Osteoarthritis. Activity modification, physical therapy, and lifestyle modifications are treatment staples. Weight loss is one of the most important lifestyle modifications and can be accomplished through a healthy diet and regular exercise. Heat (heating pad/warm towel) in the morning to help with stiffness and ice towards the end of the day or after significant activity can help. The occasional use of pain medicines such as Tylenol or NSAIDs (such as Aleve and Ibuprofen), if not contraindicated for other health reasons, can also alleviate pain. Different anti-inflammatory gels may temporarily help as well. Use of knee braces and assistive devices such as a cane may help decrease the load put upon the joint and reduce pain.
Injections such as cortisone, viscosupplements, and platelet rich plasma (PRP) are commonly used. Follow the links to learn more about viscosupplementation and PRP. Cortisone is usually only recommended as a last resort given there is evidence that cortisone can soften and degenerate the articular cartilage, thereby paradoxically accelerate progression of the arthritis, especially if given multiple times. Dr. Steven Lee will discuss all of these options with you during your visit.
Surgical Treatment:
Surgery is usually recommended once all nonoperative treatment options have been exhausted and the pain and functional limitations can no longer be tolerated. The type of surgery performed depends on the patient’s age, activity level, and arthritis severity. Some surgical options are minimally invasive: knee arthroscopy, synovectomy, chondroplasty, loose body removal, and microfracture. These procedures involve introducing a small camera and other instruments into the knee joint to either remove degenerative tissue (synovectomy), remove degenerative cartilage and smooth the joint surface (chondroplasty), remove loose pieces of bone, or even drill small holes into bone that was once covered by cartilage to stimulate the formation of new tissue similar to cartilage (microfracture).
A knee replacement may be recommended for patients with significant arthritis. Knee replacement can either be partial or full (total) and depends on a variety of factors. Both surgeries involve removing the diseased ends of bone and resurfacing those bones with special implants designed to recreate normal knee anatomy. This creates a new prosthetic joint surface and facilitates smooth joint motion. The decision to have a total joint replacement is a big decision and a personal decision. Whether to have it done or not solely rests on the patients pain, functional deficits, and tolerance of surgery, not what an Xray may show or what the doctor’s opinion may be.
Total knee replacements can now be done as an outpatient (meaning going home the same day) in some select patients. The benefits of which are less exposure to potentially other sick patients in a hospital, being able to recover in the comfort of your own home, including sleeping in your own bed! Inquire with your surgeon about whether you are a candidate for outpatient knee replacement surgery.
Recovery Expectations:
The postoperative protocol and recovery depends on which surgical treatment is utilized. Physical therapy is usually indicated after surgery to regain strength and restore range of motion. Depending on the type of procedure done, patients may have to keep weight off the operated knee with crutches or a cane.
For total knee replacements, patients are asked to walk bearing full weight on the operated knee even from the first day. Physical therapy can be somewhat grueling and will typically last at least 2-3 months. While the functional life of a knee replacement varies, many can last more than 20 years.
Immediate Post-Operative Instructions
Please refer to the following pages for more information:
*It is important to note that all of the information above is not specific to anyone and is subject to change based on many different factors including but not limited to individual patient, diagnosis, and treatment specific variables. It is provided as an educational service and is not intended to serve as medical advice. Anyone seeking specific orthopedic advice or assistance should consult Dr. Steven Lee or an orthopedic specialist of your choice.
*Dr. Steven Lee is a board certified orthopedic surgeon and is double fellowship trained in the areas of Hand and Upper Extremity Surgery, and Sports Medicine. He has offices in New York City, Scarsdale, and Westbury Long Island.