Osteoarthritis Overview

Data from 2003-2005 from the National Health Interview Survey showed some impressive information about the prevalence or arthritis in the United States. Forty-six million American adults reported doctor-diagnosed arthritis, making arthritis one of the nation’s most common health problems. Not only is arthritis highly prevalent among U.S. adults, it is the leading cause of disability as well, with 19 million (9% of all adults) suffering from arthritis and arthritis-attributable activity limitation.1 Arthritis is also associated with:

  • – Work-related disability
  • – Reduced quality of life
  • – High health-care costs

As the population ages, arthritis is expected to affect an estimated 67 million adults in the United States by 2030, with an estimated 25 million adults (37%) of those with arthritis reporting arthritis-attributable activity limitations.2 Distribution within the population is a little less well-described. Disparities exist in the statistics with regard to arthritis and activity limitations. Women, older adults, persons with little education, or those who are obese, overweight, or physically inactive are more likely to be affected. In unadjusted analyses, doctor-diagnosed arthritis was less prevalent among non-Hispanic blacks and Hispanics than among non-Hispanic whites; however, both groups reported greater proportions of persons with arthritis-attributable activity limitation.

Arthritis is actually not a single disease, but a constellation consisting of more than 100 different conditions. Among the most common are osteoarthritis (OA) and rheumatoid arthritis (RA).

Osteoarthritis

Osteoarthritis (OA) is the most common arthritic condition, affecting an estimated 27 million Americans usually 60 years of age or older.3 OA is primarily a disease of the cartilage that results in local tissue response, mechanical change, and ultimately failure of function. It is also often referred to as Degenerative Joint Disease. Almost any joint in the body can develop osteoarthritis, but the joints most commonly involved in presentation of OA typically include the following:

  • – Cervical spine
  • – Thoracic spine
  • – Lumbosacral spine
  • – Distal interphalangeal joints
  • – Feet and ankles
  • – First carpometacarpal joints
  • – Hips
  • – Knees
  • – Proximal interphalangeal joints

Primary osteoarthritis is mostly related to aging. With aging, integrity and makeup of cartilage degenerates, resulting in flaking or formation of tiny crevasses. In advanced cases, there is a total loss of cartilage cushion between the bones of the joints. Repetitive use of the worn joints over the years can irritate and inflame the cartilage, causing joint pain, swelling, and stiffness. Loss of the cartilaginous cushioning between the bones of the affected joints causes friction between the bones, leading to pain and limitation of joint mobility. The inflammation of the cartilage can also stimulate new bone outgrowths (spurs, also referred to as osteophytes) to form around the joints which can lead to further inflammation. Although osteoarthritis occasionally can develop in multiple members of the same family, there is lack of good evidence to clearly support a genetic basis for this condition.

Secondary osteoarthritis refers to arthritis resulting from another disease or condition, such as previous trauma, prior surgery, or obesity. Obesity is a known risk factor for the development and progression of knee osteoarthritis and possibly osteoarthritis of other joints. For example, obese adults are up to 4 times more likely to develop knee osteoarthritis than normal weight adults.4

Patients usually present with symptoms of morning stiffness usually lasting no longer than 20–30 minutes. Presence of stiffness that persists longer should generate inquiry about other possible diagnoses. In the absence of injury, involvement of the shoulders, wrists, and elbows is uncommon.

Diagnosis of OA is assisted by attention to the following:

  • Clinical presentation
    • History and physical findings
      • Presenting symptoms may include:
        • – Deep aching joint pain that gets worse with activity or weight-bearing, and is relieved by rest
        • – Pain that is worse on initiating activity after a period of rest
        • – “Grating” sensation or noise from the joint with motion
        • – Increased pain associated with climate change (e.g., humidity or cold)
        • – Joint swelling
        • – Heberden’s nodes (knobby bony deformities at the smallest joint of the end of the fingers)
        • – Limited range of motion
        • – Associated muscle weakness around arthritic joints
  • Radiographic evaluation
    • – Joint space narrowing of large, weight bearing joints
    • – Increased sub-chondral bony sclerosis
    • – Presence of osteophytes
    • – Small synovial effusions with non inflammatory pathology findings
    • – Laboratory tests are generally not useful and are often normal

The Osteoarthritis Research Society International (OARSI) recently published a set of guidelines5 for management of patients with osteoarthritis of the hip and knee.

The purpose of these guidelines was to “provide concise, patient focused, up to date, evidence-based, expert consensus recommendations for the management of hip and knee OA, which are globally relevant” to physicians and allied health care professionals who manage OA in both primary care and expert practice settings. They also take into account that there may be regional variations in availability of some treatment approaches.

After rigorous review, the following recommendations were made within the context of the four major categories of treatment:

General

  • A management plan that utilizes a combination of pharmacologic and non- pharmacologic modalities, with the intention of curbing disease progress, managing pain, and improving quality of life

Non-pharmacologic

  • Information access and patient education about:
    • – The objectives of treatment
    • – Pacing of activities
    • – Necessary changes in lifestyle (e.g., exercise, weight reduction)
    • – Compliance to therapy
    • – Self-help and patient-driven treatments
  • – Regular contact (e.g., by phone) to assess status
  • – Physical therapy and muscle strengthening
  • – Encouragement for overweight patients to lose weight, and maintain loss
  • – Use of mobility aids such as a cane, crutch, or walker
  • – Bracing when appropriate to reduce pain, improve stability, and diminish fall risk
  • – Appropriate footwear
  • – Complementary techniques including:
    • – Thermal applications
    • – Transcutaneous electronic nerve stimulation (TENS)
    • – Acupuncture

Pharmacologic

  • – Acetaminophen (up to 3 gm/day) for initial analgesic treatment of mild to moderate pain
    • – Non-steroidal anti-inflammatory drugs (NSAIDS) at the lowest effective dose, avoiding long-term use if possible*
    • – Topical local anesthetics, NSAIDS or capsaicin as alternatives or adjuncts to analgesic therapy
    • Intra-articular injections:
      • – Corticosteroids, particularly when there is refractory pain or distinct signs of local inflammation
      • Hyaluronate may also be useful, but may take a reasonable amount of time to demonstrate efficacy
    • – Opioids for the treatment of refractory pain with the above-mentioned treatments, along with consideration of surgical intervention

*In patients with increased GI risk, either a COX-2 selective agent or a non-selective NSAID with co-prescription of a proton pump inhibitor (PPI) for gastroprotection may be considered. NSAIDs, including both non-selective and COX-2 selective agents, should always be used with caution in patients with cardiovascular risk factors.

Surgical

  • – Joint replacement arthroplasties are effective and cost-effective interventions for patients with significant symptoms, and/or functional limitations associated with a reduced health-related quality of life, despite conservative therapy.

These guidelines put forth some basic principles that are likely worthwhile to incorporate as a treatment plan for OA of any joint, depending on the logical application to the affected joint or joints. Goals of OA treatment are best directed towards:

  • – Maintaining range of motion or improving joint movement
  • – Increasing joint strength
  • – Reducing limitation of functional capacity
  • – Pain relief

References

  1. 1. Hootman JM, Bolen J, Helmick CG, Langmaid G. Prevalence of doctor-diagnosed arthritis and arthritis-attributable activity limitation—United States, 2003-2005. MMWR. 2006;55(40):1089–1092.
  2. 2. Hootman JM, Helmick CG. Projections of US prevalence of arthritis and associated activity limitations. Arthritis Rheum. 2006;54:226–9.
  3. 3. Lawrence RC, Felson DT, Helmick CG, et al. Estimates of the prevalence of arthritis and other rheumatic conditions in the United States. Part II. Arthritis Rheum. 2008 Jan;58(1):26-35.
  4. 4. Felson DT, Zhang Y. An update on the epidemiology of knee and hip osteoarthritis with a view to prevention. Arthritis Rheum. 1998;41(8):1343–1355.
  5. 5. Zhang W, Moskowitz RW, Nuki G, et al. OARSI recommendations for the management of hip and knee osteoarthritis, Part II: OARSI evidence-based, expert consensus guidelines. Osteoarthritis Cartilage. 2008 Feb;16(2):137-62.

A corresponding version of this article that is appropriate for your patients, titled “Oh my aching back: Learning about spinal osteoarthritis” is now available at www.painACTION.com.