A recent publication in the New England Journal of Medicine, written by Nancy Lane, University of California at Davis, underscores many of the principles of osteoarthritis management we have discussed in this forum. Dr. Lane reviews the clinical problem of osteoarthritis in the United States, and discusses in detail the diagnostic modalities, treatment strategies and areas of controversy which surround its management.
Let me take a moment to review the most important topics discussed by Dr. Lane.
Osteoarthritis is the most common form of arthritis in American adults, but there is frequently little relationship between the appearance of osteoarthritic joints on X-ray and symptoms of pain in patients. Plain films demonstrate osteoarthritis in 5 percent of Americans over the age of 65. Approximately 200,000 hip replacement surgeries are performed in this country every year for both primary and secondary osteoarthritis (the latter is arthritis caused by another illness). Some risk factors for primary disease include advancing age, a positive family history of osteoarthritis, previous injury to the joints, obesity with excess weight bearing, and jobs requiring repetitive lifting and standing. Secondary causes of osteoarthritis include endocrine disorders (thyroid dysfunction for example), coexisting crystalline arthritis, developmental abnormalities involving the hip and metabolic diseases of bone and cartilage.
Osteoarthritis sufferers usually have pain with walking, standing and weight-bearing. The pain frequently begins with nagging symptoms which progress to constant discomfort. Pain is invariably felt in the groin, with a grinding sensation noted with hip flexion (when you move the thigh forward) and internal rotation. Rest frequently relieves symptoms, although prolonged or frequent morning stiffness, nighttime pain and discomfort with rest suggests disease progression. Physical examination of the hip demonstrates pain upon internal or external rotation with the knee in full extension. Frequent mimics of osteoarthritis include trochanteric bursitis, sciatica and inflammation of the lateral femoral cutaneous nerve, amongst others. Plain films confirm the clinical impression of osteoarthritis, with joint space narrowing and osteophyte formation. Blood tests are not helpful, and aspiration of the hip (performed infrequently), demonstrates bland synovial fluid without crystals or evidence of infection. MRI is usually unnecessary because conventional x-rays will almost always confirm the clinical impression of osteoarthritis.
Goals of treatment are the relief of pain and preservation of function. Lifestyle modification in the osteoarthritis patient is the most important form of therapy. Weight reduction in obese patients and institution of analgesic medication (or pain relievers) is required. Patients usually start with acetaminophen (such as Tylenol), followed in sequence by nonsteroidals or NSAIDs (such as Motrin or Celebrex) and opiate analgesics (such as OxyContin). Opitate painkillers may be used particularly in those who cannot tolerate acetaminophen or experience toxicity from anti-inflammatory medications. Glucosamine and chondroitan may be beneficial, although placebo-controlled trials have not demonstrated their benefit in osteoarthritis. Joint injection of the hip with lidocaine and corticosteroids is technically difficult, requires ultrasound or fluoroscopic guidance, and confers only short-term benefit. Hip replacement surgery is the definitive form of therapy for patients who do not benefit from analgesic medications, weight reduction and alterations in lifestyle. Recent advances in material science have made hip replacement more tolerable, particularly for older patients with limited athletic involvement (for whom the replacement will outlive the patient). Smaller incisions, shortened hospital stays and aggressive rehabilitation make hip replacement a popular option, even for younger patients with advanced disease.