FAQS on Knee Arthritis
Knee arthritis impacts every second American above 75 years. By 2030, about 67 million people are expected to suffer from the musculoskeletal joint disorder, which continues to be the foremost reason of lost work time and disability among people older than 50 years. The word arthritis is sourced from two Greek and Latin words, “arthron” referring to joint and “itis” suggesting inflammation. Thus, arthritis means joint inflammation. About 12 percent of Americans less than 25 years also exhibit signs of knee arthritis.
What is knee arthritis?
Knee arthritis occurs when inflammation causes pain, stiffness, and swelling in the knee joint. Though arthritis affects any joint, knee disorder is the most commonly reported arthritis because of its crippling effect. It makes performance of everyday activities, including walking, difficult, and leads to disability.
According to the origin, knee arthritis is broadly classified into four categories.
- Osteoarthritis or degeneration and damage of cartilage elasticity following wear and tear.
- Rheumatoid arthritis or autoimmune inflammatory disorder damaging the synovial membrane around the knee joint. This results in swelling, pain, and stiffness in the knee.
- Infectious arthritis or infection inflaming the soft tissues around the knee joint.
- Posttraumatic arthritis or injuries to the knee surface and ligaments forcing the joint to undergo additional wear
How does knee arthritis occur?
The knee joint comprises of three components – kneecap, thighbone, and shinbone. A tough, slippery set of fibrous tissues, known as articular cartilage, connects the three with each other. It cushions the joints like a shock absorber and ensures their smooth movement without friction with each other. Fluid released by the synovial membrane located around the knee joint keeps the cartilage lubricated and slippery.
The cartilage is damaged, thinned down, or subject to wear and tear due to excessive stress, injury, or degenerative factors, the bone heads come into contact with each other. They rub with one another as we move and this leads to the development of spurs or tiny bony formations. As the space between bones is reduced, friction increase and with it the risk of inflammation and pain. And knee condition sets in.
What are the symptoms of knee arthritis?
- Painful, inflamed knee joint
- Stiff and swollen knee joint
- Restricted ability to bend or straighten the knee due to pain
- Worsening pain and swelling when you wake up in the morning or try to get up after sitting for a long time
- Walking or running leading to pain
- Locking or sticking sensation in the knee joint while walking
- Vigorous activity may cause pain to flare up.
- Knee weakness or buckling
- Worsening pain in the rainy and cold weather
- Limited weight bearing ability
- Poor range of motions
What are the main causes knee arthritis?
- Degeneration of knee joint cartilage
- Overuse of knee join leading to wear and tear
- Excessive stress causing ligament wear and tear
- Injury or damage to the knee
- Rheumatoid arthritis
- Repeated stress more than the knee joint able to withstand
- Excessive weight bearing on or twisting of the knee
- Bone spurs
- Muscle weakness around the knee joint
- Obesity causing stress on the knee joint
- Paget’s disease
- Gout or uric acid deposition
Who are at the risk of knee arthritis?
The following factors influence the increased risk of knee arthritis.
- Age increases the chance of cartilage degeneration.
- Women are more vulnerable than men.
- Obesity and sedentary lifestyle put added pressure on the knee joint while keeping it immobilized for longer durations. Protein deposition also contributes to inflammation of tissues around the joint and causes arthritis.
- Injuries may damage the joint cartilage.
- Hereditary factors, bone deformities, gout deposition, and diabetes also play a role in knee arthritis.
How is knee arthritis diagnosed?
Physical examination of the knee is the most common way of diagnosing the disorder. Doctors examine it for swelling, tenderness, instability, grating sensation, walking difficulties, and muscle injury. Patients also perform passive and active knee movements during the evaluation. X-rays may be suggested to identify exact cause or type of knee arthritis.
What are the treatment methods available for knee arthritis?
- Medication: Non-steroidal anti-inflammatory medications are recommended to cut down inflammatory pain and increase mobility. There are also disease-modifying anti-rheumatic drugs to treat rheumatoid arthritis.
- Lifestyle modifications: Losing weight, dietary restrictions to prevent gout formation, lower impact activities, flexibility enhancing workouts, and similar changes help reduce inflammation and protect the knee joint against degeneration.
- Physical therapy: Certain exercises help promote knee joint flexibility, strengthen adjoining muscles, and prevent protein deposition. It can also be a preventive measure to protect knee against arthritis.
- Assistive devices: Support braces, unloader braces and wearing shock-absorbing shoes are there to help patients with knee arthritis to support the knee load and maintain functional stability while keeping stress away from the affected area.
- Conservative pain management: Pain relieving oils, ointments, magnetic pulse therapy, icing, acupuncture, massage, and heat therapy also help in overcoming knee arthritis pain.
- Prolotherapy or regenerative injections: Stem cells or platelet-rich plasma are injected to the ligaments to help them recover from injury and heal. The process is effective in restoring cartilages to their original shape and function and preventing their wear and tear.
- Corticosteroid injections: Steroid is injected to suppress swelling, inflammation, and pain associated with knee arthritis.
- Anesthetic injections: Lidocaine or other anesthetic medications are injected to lessen inflammation and pain.
- Lubricant injections: Hyaluronic acid, a natural lubricant, helps keep the cartilage slippery and prevent joint stiffness. It also revives the damaged ligaments.
- Viscosupplementation/ Arthrocentesis injections: These injections recharge joint fluids that keep the cartilage healthy and lubricated.
- Surgery for knee arthritis:
- Arthroscopy or minimal invasive surgery to repair ligament tears.
- Cartilage grafting or replacing damaged knee joint cartilage tissues with healthier cartilage tissues
- Synovectomy or removal of the damaged knee joint lining
- Osteotomy or restructuring of bones joining each other at the knee joint to divert the weight off from the partially damaged side of the joint to the side unaffected by knee arthritis
- Knee replacement surgery to replace the damaged bones and cartilages partially or completely by metal or plastic devices
Osteoarthritis: Care and management in adults; NICE Clinical Guideline (February 2014)
Belo JN, Berger MY, Reijman M, et al; Prognostic factors of progression of osteoarthritis of the knee: a systematic review of observational studies. Arthritis Rheum. 2007 Feb 15;57(1):13-26.
Recht MP, Kramer J, Marcelis S, Pathria MN, Trudell D, Haghighi P, et al. Abnormalities of articular cartilage in the knee: analysis of available MR techniques. Radiology. May 1993;187(2):473-8.
Felson DT, Zhang Y, Anthony JM, Naimark A, Anderson JJ. Weight loss reduces the risk for symptomatic knee osteoarthritis in women. The Framingham Study. Ann Intern Med. Apr 1 1992;116(7):535-9.
Felson DT. Epidemiology of hip and knee osteoarthritis. Epidemiol Rev. 1988;10:1-28
Valdes AM, Spector TD. Genetic epidemiology of hip and knee osteoarthritis. Nat Rev Rheumatol. Jan 2011;7(1):23-32.
Jordan JM, Helmick CG, Renner JB, Luta G, Dragomir AD, Woodard J, et al. Prevalence of knee symptoms and radiographic and symptomatic knee osteoarthritis in African Americans and Caucasians: the Johnston County Osteoarthritis Project. J Rheumatol. Jan 2007;34(1):172-80.
Chapple CM, Nicholson H, Baxter GD, Abbott JH. Patient characteristics that predict progression of knee osteoarthritis: A systematic review of prognostic studies. Arthritis Care Res (Hoboken). Aug 2011;63(8):1115-25.
Altman R, Asch E, Bloch D, Bole G, Borenstein D, Brandt K, et al. Development of criteria for the classification and reporting of osteoarthritis. Classification of osteoarthritis of the knee. Diagnostic and Therapeutic Criteria Committee of the American Rheumatism Association. Arthritis Rheum. Aug 1986;29(8):1039-49.
American Academy of Orthopaedic Surgeons. Treatment of Osteoarthritis (OA) of the Knee. AAOS: American Academy of Orthopaedic Surgeons. Available at http://www.aaos.org/research/guidelines/GuidelineOAKnee.asp.
Godwin M, Dawes M. Intra-articular steroid injections for painful knees. Systematic review with meta-analysis. Can Fam Physician. Feb 2004;50:241-8.
Bellamy N, Campbell J, Robinson V, Gee T, Bourne R, Wells G. Viscosupplementation for the treatment of osteoarthritis of the knee. Cochrane Database Syst Rev. Apr 19 2006;CD005321.
Reichenbach S, Rutjes AW, Nüesch E, Trelle S, Jüni P. Joint lavage for osteoarthritis of the knee. Cochrane Database Syst Rev. May 12 2010;CD007320.