Knee osteoarthritis, or arthritis, is the wearing away of the protective cartilage surface covering the ends of the bones at the knee joint. When functioning properly, this cartilage allows smooth and painless motion. As the cartilage wears over time or after injury, the worn surfaces can create debris and cause pain, inflammation, and crepitus, or audible or palpable grinding.
Arthritis symptoms generally progress over time at an unpredictable rate and may have periods of decreased or increased pain and symptoms.
What Is Knee Osteoarthritis?
Arthritis is the physical wearing away of the protective cartilage surface covering the ends of the bones at a joint. As this cartilage wears, the joint can become painful, inflamed, and stiff.
The knee has three different compartments:
- The medial tibiofemoral compartment, between the thigh bone and shin bone on the inside of the knee
- The lateral tibiofemoral compartment, between the thigh bone and shin bone on the outside of the knee
- The patellofemoral compartment, between the kneecap and thigh bone
Arthritis may be limited to a portion of the knee or involve more of the joint surfaces.
Causes and Risk Factors
Knee arthritis can develop as cartilage wears over time or after an injury. The rate at which symptoms progress is unpredictable and may occur over months, years, or decades.
Symptoms
Symptoms of knee osteoarthritis may include:
- Pain
- Inflammation
- Crepitus, or audible or palpable grinding of the joint surfaces
- Stiffness when beginning to move after a prolonged period of rest or inactivity
- Morning stiffness
Symptoms may increase or decrease over time.
Treatment
Conservative, non-operative treatment is used to help manage knee arthritis symptoms. Treatment options may include:
- Activity modification: Continue to use and move the knee without overusing it. Keeping the intensity, duration, and frequency of activity below the level that causes joint pain and aggravation can help reduce symptoms.
- Gentle strengthening and stretching exercises: Appropriate exercises can improve overall knee function and reduce pain. A short course of physical therapy can help patients learn an appropriate daily exercise regimen.
- Non-impact activities: Swimming, water exercises, skating, and biking can strengthen muscles and maintain joint function while reducing impact on the knee.
- Weight loss: Proper diet and exercise can help decrease stress on the knee joint and improve arthritis-related pain.
- Assistive devices: Knee unloader braces, a cane, or a walker may help reduce forces across the joint and provide relief.
- Medications: Tylenol® and anti-inflammatory medications may help manage arthritis symptoms. Anti-inflammatory medications may be available over the counter or prescribed by a doctor.
- Injections: Steroid injections can reduce symptoms by decreasing inflammation in the joint. Hyaluronic acid, or gel, injections may also provide relief.
- Biologics: Treatments such as PRP, stem cells, amniotic fluid, growth factors, tissue scaffolds, and progenitor cells cannot restore cartilage and would not be expected to improve symptoms.
Surgery is considered a last resort and may be appropriate when reasonable conservative measures have been exhausted and pain continues to significantly affect quality of life.
Surgical options include:
- Arthroscopy: Arthroscopy can clean up loose ends of torn cartilage and treat focal, small and limited breaks in the cartilage surface. Outcomes for diffuse cartilage damage involving most of the joint surface are less predictable, and initial good responses may be short lived. Removing loose cartilage, torn meniscus fragments, or loose bodies that cause mechanical symptoms can be helpful.
- Osteotomy: Osteotomy involves cutting and realigning the bones around the knee to shift the load from the worn and damaged side of the joint to the more normal side. It may be used for arthritis limited to part of the knee in younger, not overweight individuals who intend to maintain higher activity levels that may not be appropriate following joint replacement.
- Unicompartmental replacement: A unicompartmental, or single-compartment, knee replacement can resurface damaged and arthritic joint surfaces in one of the knee’s three compartments when the others remain in good condition. The advantage is less surgery and more normal knee mechanics and function. The disadvantage is that it may eventually require revision to a total knee replacement. Robotic and computer navigation are improving the ability to accurately position unicompartmental implants and theoretically improve survivorship.
- Total knee replacement (TKA): Total knee replacement replaces damaged and arthritic joint surfaces with metal and plastic while maintaining the remaining bone, tendons, and ligaments.
Recovery and Outcomes
Recovery depends on the surgical procedure performed.
Following an osteotomy, protected weightbearing is required for six weeks or longer, with approximately four to six months before returning to activity. If successful, patients can often expect reasonable pain relief for five to 10 years before the remainder of the knee develops arthritis and may need to be converted to a total knee replacement.
Recent data cited in Dr. Chudik’s approved patient material indicates that unicompartmental replacement outcomes and survival are approaching those of total knee replacement.
Total knee replacement has very successful outcomes regarding pain relief and achieving functional motion.
When to See Dr. Chudik
Contact Dr. Chudik’s office if your symptoms worsen. If reasonable conservative treatments have been exhausted and knee pain continues to significantly affect your quality of life, an evaluation can help determine appropriate treatment options.
Call 630-324-0402, request an appointment online, or email contactus@chudikmd.com.