Osteoarthritis (OA) A slowly progressive, degenerative joint disease characterized by variable changes in weightbearing joints.
Also known as Osteoarthrosis or Degenerative Joint Disease Most common and most frequently disabling of the joint disorders Often begins at 30 years old and peaks between 50 and 60 years old By 40 years of age, 90% of the population have degenerative changes in their weight-bearing joints, even though clinical symptoms are usually present Prevalence of OA is between 50%-80% in the elderly Affects both sexes about equally
Classifications: Primary (Idiopathic) no prior event or disease related to the OA Secondary resulting from previous joint injury or inflammatory disease
Risk Factors Age Increasing age directly relates to the degenerative process in the joint because the ability of the articular cartilage to resist microfracture with repetitive low loads diminishes with age Obesity Trauma Genetic predisposition Congenital abnormalities
Primary Clinical Manifestations: Pain, Stiffness and Functional Impairment Pain caused by an inflamed synovium, stretching of the joint muscles or ligaments, irritation of nerve endings periosteum over osteophytes (bone spurs), trabecular microfracture Stiffness most commonly experienced in the morning or after awakening. It usually lasts less than 30 minutes and decreases with movement Functional Impairment results from pain on movement and limited motion caused by structural changes in joints Joint grating with movement OA occurs most often in weight-bearing joints (hips, knees, cervical and lumbar spine), but the proximal and distal finger joints are often involved Bony nodes may be present; on inspection and palpation, these are usually painless, unless inflammation is present a. Heberdens nodes bony overgrowth at terminal interphalangeal joints b. Bouchards nodes boy overgrowth at the proximal interphalangeal joints
Assessment and Diagnostic Findings
Tender and enlarged joints Inflammation OA is characterized by a progressive loss of joint cartilage , which appears on x-ray as a narrowing of the joint space. Reactive changes occur at the joint margins and on the subchondral bone in the form of oseophytes as the cartilage attempts to regenerate. Neither the presence of osteophytes or joint space narrowing alone is specific for OA; however, when combined, these are sensitive and specific findings. Blood tests are not useful in the diagnosis of OA.
Medical Management Preventive measures can slow the degenerative process. These include: weight reduction, prevention of injuries, perinatal screening for congenital hip disease, and ergonomic modifications Conservative treatment measures include patient education, the use of heat, weight reduction, joint rest and avoidance of joint overuse, orthotic devices (eg, splints, braces) to support inflamed joints, isometric postural exercises, and aerobic exercise
Pharmacologic Therapy Directed toward symptom management and pain control In most patients with OA, the initial analgesic therapy is acetaminophen NSAIDs Patients who are at increased risk for gastrointestinal complications, especially gastrointestinal bleeding, have been managed effectively with COX-2 enzyme blockers Viscosupplementation, the injection of gel-like substances (hyaluronates), into a joint (intraarticular) is thought to supplement the viscous properties of synovial fluid
Surgical Management In moderate to severe OA, when pain is severe or because of loss of function, surgical intervention may be used. Osteotomy to alter the distribution of weight within the joint. Osteotomy ("bone cutting") is a procedure in which a surgeon removes a wedge of bone near a damaged joint. This shifts weight from an area where there is damagedcartilage to an area where there is more or healthier cartilage. In osteoarthritis, cartilage breakdown in the knee often is much greater in the inner part of the knee joint, often resulting in a bowlegged appearance. In knee osteotomy for osteoarthritis of the inner knee, your surgeon removes bone from the outer side of the large lower leg bone (tibia) near the knee. This tilts your body weight toward the outer, healthier part of the knee cartilage and away from the inner, damaged cartilage. Weight is spread more evenly across the joint cartilage. After removing the bone wedge, your surgeon will bring together the remaining bones and secure them, most often with either pins
or staples. An osteotomy forosteoarthritis of the outer knee is just the opposite-your surgeon will remove bone from the inner side of the lower leg to shift the weight toward the inner knee. Arthroplasty removal of loose pieces of bone and cartilage from the joint if they are causing symptoms of buckling or locking resurfacing (smoothing out) bones (joint resurfacing).
Nursing Management Goals: Pain management and optimal functional ability Weight loss and exercise. Exercises such as walking should be begun in moderation and increased gradually. Patients should plan their daily exercise for a time when the pain is least severe or plan to use an analgesic agent, if appropriate, before exercising. Canes or other assistive devices for ambulation should be considered Nonpharmacologic comfort measures: a. Warm compresses to sore joints b. Massage surrounding muscles, not over inflamed joints c. Promote adequate rest and reduction of stress
