Osteoarthritis of the Knee
Illustration showing a healthy knee joint (left) and a knee joint that has developed Osteoarthritis (right).
What are the other Names for this Condition? (Also known as/Synonyms)
- Degenerative Osteoarthrosis of Knee Joint
- Knee Osteoarthritis
- Knee Osteoarthrosis
What is Osteoarthritis of the Knee? (Definition/Background Information)
- Osteoarthritis is a painful joint disorder characterized by the progressive degeneration of the articular cartilage that covers the bone surface of joints. Over time, the cartilage of the joint wears down. Studies have indicated that osteoarthritis has a genetic component to it
- Osteoarthritis of the Knee is a gradual progressive degenerative disorder that affects the knee joint(s); it can affect either one or both knees
- Individuals, who develop the condition, begin to experience pain and stiffness in the knee that usually increase with age
- Treatment associated with Osteoarthritis of the Knee includes both nonsurgical and surgical methods. Prognosis of the condition is good with treatment, in a majority of individuals
Who gets Osteoarthritis of the Knee? (Age and Sex Distribution)
- Osteoarthritis of the Knee may occur in individuals of all age, race, ethnic group, and belonging to any gender
- A high percentage of individuals, who develop this degenerative, debilitating, and progressive disorder, are middle-aged to elderly women
- Middle-aged men and young athletes, who sustain traumatic joint injuries (while participating in rough or high-impact sports activities), are higher prone to developing osteoarthritis
- Women (especially after menopause), are more likely to develop the degenerative condition, than men
What are the Risk Factors for Osteoarthritis of the Knee? (Predisposing Factors)
Risk factors of Osteoarthritis of the Knee include:
- Osteoarthritis of the Knee is rarely diagnosed in individuals under 40 years old. However, since it is a gradually progressing disorder, the risk of developing this condition usually increases with age
- Women are higher susceptible to the condition than men, especially after menopause
- Individuals, who sustain a joint injury, while participating in rough/high-impact sports, such as football, tennis, and basketball
- Abnormal pressure on the joints, due to excess body weight (obesity)
- Repetitive stress on the knee associated with certain occupations, such as with farming, construction-related work, can increase the risk
- Gout: A medical condition caused by a high level uric acid within blood
- Paget’s disease of bone: A rare, chronic bone disorder characterized by abnormal growth and deformity of bones
- Hypothyroidism: A medical condition characterized by the body’s inability to produce enough thyroid hormone
- Individuals, who have diabetes, a chronic medical condition characterized by excessive levels of sugar in blood
It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.
Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.
What are the Causes of Osteoarthritis of the Knee? (Etiology)
Currently, the underlying cause of osteoarthritis is unknown. However, the causes associated with Osteoarthritis of the Knee include:
- An injury to the knee joint, while participating in sports, such as football, tennis, and basketball
- Repetitive stress on the knee, due to certain occupations, such as farming or construction
- Obesity, causing abnormal pressure on the joints
- Some arthritic disorders have a genetic prevalence: Individuals with an immediate family member or relative having a history of osteoarthritis may also develop this disorder
- Progressive damage of the joint cartilage (due to various reasons) is a key factor
What are the Signs and Symptoms of Osteoarthritis of the Knee?
Osteoarthritis is a gradual and progressive disorder that usually worsens over time. Common signs and symptoms associated with Osteoarthritis of the Knee include:
- Noticeable pain, tenderness
- Stiffness, reduced mobility of the knee joint
- Formation of bone spurs around the knee joint
How is Osteoarthritis of the Knee Diagnosed?
Diagnostic methods that a physician may use to help diagnose Osteoarthritis of the Knee include:
- Physical examination: The physician will perform a thorough physical examination to determine, if the individual has osteoarthritis. In addition to this, a complete medical history may aid in arriving at a definitive diagnosis
- X-ray of the knee joint: X-rays use radiation in order to produce images of the knee, which can help the physician rule out other possible causes for knee discomfort
- Various blood tests: A blood test is a routine test used to diagnose various disease and conditions. During this test, a needle is used to take a blood sample that is withdrawn from an artery or vein. This blood sample is taken to a laboratory for analysis
- Joint fluid analysis of knee joint: Occasionally, fluid may accumulate around a joint. Analysis of this fluid will give clues regarding the cause of the joint fluid accumulation, which causes pain and disability. A needle is inserted into the joint space and the accumulated fluid aspirated with a syringe. It is then sent to a laboratory for analysis, to determine:
- The type of cells present in the fluid
- Chemical composition of the fluid
- The presence of crystals (examination of fluid under a microscope)
- If an infection is suspected as a cause of accumulation of the joint fluid, then a joint fluid culture may be performed. The culture of joint fluid will confirm an infection of the knee joint, as the cause of arthritis (termed infective arthritis)
- Ultrasound imaging of knee joint: The use of high-frequency sound waves to generate a thorough image of the knee
- CT, MRI scan of the knee joint
Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.
What are the possible Complications of Osteoarthritis of the Knee?
Osteoarthritis is a progressive condition that gradually worsens over time. The complications of Osteoarthritis of the Knee could include:
- Chronic pain and stiffness within the knee joint, which may prevent individuals from performing their daily routine activities
- Permanent disability
- Due to a lack of mobility, the incidence of obesity, heart disease, and hypertension, could increase
How is Osteoarthritis of the Knee Treated?
The treatment of Degenerative Osteoarthritis of Knee includes nonsurgical and surgical methods. A healthcare provider may start with non-surgical treatment methods, before adopting surgical procedures and techniques. These include:
- Rest: Any activity that aggravates the knee condition further should be avoided. The physician usually advises to refrain from all such activities, until the symptoms stop
- Heat and ice: Applying a damp heated towel or ice to the knee joint, can help reduce pain and swelling
- Splint or brace: A physician may prescribe some type of padded splint or cast, to help keep the knee in a stable position and limit movement, to help the injury heal
- Non-steroidal anti-inflammatory medication: Medications, such as ibuprofen and naproxen, can help decrease the knee pain and swelling
- Corticosteroid medications, such as prednisone, help provide temporary relief of symptoms, and in improving the range of knee motion. It is important to note that corticosteroid injections only give temporary relief. Prolonged episodes of such injections, may injure the knee joints in the long-run
- Viscosupplementation: Normal fluid within a joint contains a material called hyaluronic acid. When a knee joint is affected by osteoarthritis, a reduction of hyaluronic acid level occurs within the joint. Such a decreased acid level will decrease the ability of the joints to lubricate. Viscosupplementation is a minimally-invasive technique that is commonly used, when treating osteoarthritis. During this procedure, small doses of hyaluronic acid are injected into the knee to relieve pain
- Physical therapy: After the symptoms have decreased, it is important to begin some light motion exercises. Physical therapy may help restore strength, as well as provide flexibility, to the muscles
Surgical treatment measures include:
- Knee joint fusion: Joint fusion is a surgical technique that involves the removal of the arthritic part within the joint and fusing two surrounding bones together. The purpose of this procedure is to relieve pain, stabilize the joint, and regain some range of motion in the knee
- Knee joint osteotomy: Osteotomy is a surgical intervention tool that involves moving or reshaping the arthritic part of the knee joint that is affected by osteoarthritis. Orthopedic implants, such as screws, wires, and plates, may be used to stabilize the repositioned joint
- Partial knee arthroplasty: Partial knee arthroplasty is a surgical intervention technique that involves the removal of a part of the knee joint affected by osteoarthritis. The arthritic knee joint that is removed is then replaced by a metal and plastic prosthetic implant. This procedure is recommended, if osteoarthritis affects a part of the knee joint
- Total knee arthroplasty: Total knee arthroplasty is a surgical intervention tool in which the knee joint is completely removed. The arthritic knee joint that is removed is then replaced by a metal and plastic prosthetic implant. A physician will recommend this surgical procedure, if the degenerative disorder affects the entire knee joint
How can Osteoarthritis of the Knee be Prevented?
A few recommendations to help prevent Osteoarthritis of the Knee include:
- Individuals, who maintain a healthy diet, may decrease the chance of developing this condition
- Estrogen replacement therapy can decrease the incidence of Osteoarthritis of the Knee after menopause, in women
- Using correct posture and tools that decrease stress on knee joints in the work place can decrease incidence of the knee disorder, due to occupational causes
- Proper treatment of gout
- Prompt and adequate treatment of individuals with Paget’s disease
- In individuals with hypothyroidism, prompt treatment of the thyroidal condition
- Proper treatment of diabetes
- Maintaining a healthy body weight can help prevent abnormal pressure on the joints
- Individuals, who participate in any high-risk sports, such as football and basketball, should wear appropriate safety gear to help prevent serious injuries to their joints
What is the Prognosis of Osteoarthritis of the Knee? (Outcomes/Resolutions)
- The long term prognosis of osteoarthritis depends on the severity of the degenerative disorder
- If Osteoarthritis of the Knee is detected early, and proper, aggressive treatment provided; then, the prognosis is good in a majority of individuals, if there are no serious complications
- In general, without treatment measures a high percentage of individuals, who develop this condition, may experience a lifetime of gradual degeneration associated with this debilitating disorder
Additional and Relevant Useful Information for Osteoarthritis of the Knee:
- Arthritis of the knee affects the knee joint; especially the cartilage, bone, soft tissue surrounding the joint, muscle, and tendon
The following article link will help you understand arthritis of the knee.
What are some Useful Resources for Additional Information?
American Academy of Orthopaedic Surgeons (AAOS)
6300 North River Rd. Rosemont, IL 60018-4262
Phone: (847) 823-7186
Toll-Free: (800) 346-2267
Fax: (847) 823-8125
American College of Rheumatology
2200 Lake Boulevard NE Atlanta, GA 30319
Phone: (404) 633-3777
Fax: (404) 633-1870
Email: email@example.com; firstname.lastname@example.org; email@example.com
Arthritis Foundation National Office
1330 W. Peachtree Street.; Suite 100 Atlanta, GA 30309
Toll-Free: 1 (800) 283-7800
References and Information Sources used for the Article:
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001460/ (accessed on August 20, 2014)
http://www.nlm.nih.gov/medlineplus/osteoarthritis.html (accessed on August 20, 2014)
http://www.cdc.gov/arthritis/basics/osteoarthritis.htm (accessed on August 20, 2014)
http://nihseniorhealth.gov/osteoarthritis/whatisosteoarthritis/01.html (accessed on August 20, 2014)
http://www.niams.nih.gov/health_info/Osteoarthritis/default.asp (accessed on August 20, 2014)
http://orthoinfo.aaos.org/topic.cfm?topic=a00212 (accessed on August 20, 2014)
http://www.mayoclinic.com/health/osteoarthritis/DS00019 (accessed on August 20, 2014)
http://familydoctor.org/familydoctor/en/diseases-conditions/osteoarthritis/treatment/treating-osteoarthritis-of-the-knee.html (accessed on August 20, 2014)
Helpful Peer-Reviewed Medical Articles:
Boyan, B. D., Tosi, L., Coutts, R., Enoka, R., Hart, D. A., Nicolella, D. P., . . . Kohrt, W. (2012). Sex differences in osteoarthritis of the knee. J Am Acad Orthop Surg, 20(10), 668-669. doi: 10.5435/JAAOS-20-10-668
Cianflocco, A. J. (2013). Viscosupplementation in patients with osteoarthritis of the knee. Postgrad Med, 125(1), 97-105. doi: 10.3810/pgm.2013.01.2618
Richmond, J. C. (2013). Surgery for osteoarthritis of the knee. Rheum Dis Clin North Am, 39(1), 203-211. doi: 10.1016/j.rdc.2012.10.008
Scott, C. E., Nutton, R. W., & Biant, L. C. (2013). Lateral compartment osteoarthritis of the knee: Biomechanics and surgical management of end-stage disease. Bone Joint J, 95-B(4), 436-444. doi: 10.1302/0301-620X.95B4.30536
Moseley, J. B., O'malley, K., Petersen, N. J., Menke, T. J., Brody, B. A., Kuykendall, D. H., ... & Wray, N. P. (2002). A controlled trial of arthroscopic surgery for osteoarthritis of the knee. New England Journal of Medicine, 347(2), 81-88.
Hannan, M. T., Felson, D. T., & Pincus, T. H. E. O. D. O. R. E. (2000). Analysis of the discordance between radiographic changes and knee pain in osteoarthritis of the knee. The Journal of rheumatology, 27(6), 1513-1517.
Felson, D. T. (2006). Osteoarthritis of the knee. New England Journal of Medicine, 354(8), 841-848.
Witt, C., Brinkhaus, B., Jena, S., Linde, K., Streng, A., Wagenpfeil, S., ... & Willich, S. N. (2005). Acupuncture in patients with osteoarthritis of the knee: a randomised trial. The Lancet, 366(9480), 136-143.
Berman, B. M., Lao, L., Langenberg, P., Lee, W. L., Gilpin, A. M., & Hochberg, M. C. (2004). Effectiveness of acupuncture as adjunctive therapy in osteoarthritis of the knee: a randomized, controlled trial. Annals of internal medicine, 141(12), 901-910.