Practical Tips in the Treatment of Osteoarthritis of the Hip
The American College of Rheumatology (ACR) recently revised its recommendations for treatment of osteoarthritis (OA) of the hand, hip, and knee.1 The newly revised recommendations add to the recommendations of three other organizations that have published arthritis treatment guidelines in the last 10 years. These include the European League Against Rheumatism (EULAR), Osteoarthritis Research Society International (OARSI), and the British National Institute for Health and Clinical Excellence (NICE).2-4 In a previous issue, we highlighted the treatment recommendations for OA of the knee.5 In this educational review, we will focus on the management of OA of the hip—the second most common form of OA—using the ACR guidelines as the standard, and then discuss other treatment options that are available to practitioners.
Osteoarthritis is a common cause of pain and disability in adults. Approximately 14% of the population over age 25 suffer from OA and 1 out of 3 individuals over 65 years of age are affected.6 Hip OA affects between 3% to 7% of patients over age 55.7,8 There is a highly heritable component associated with OA; in fact, 60% of women have a genetic contribution.9 Among the genes that have been linked to OA are several that are involved in the development and maintenance of joint shape, including members of the Wingless (Wnt) and the bone morphogenetic protein families. Important genetic markers for the development and progression of the disease are currently under research.9
There is no cure or treatment to prevent the development of OA. Therefore, treatment is aimed at reducing pain and improving function. The ACR guidelines, which focused on pharmaceutical and non-pharmaceutical therapies, used the Grades of Recommendation Assessment, Development, and Evaluation (GRADE) approach for classifying current recommendations.1,10-12 Using this approach, interventions received one of four designations: strongly recommend, conditionally recommend, conditionally not recommend, and no evidence/evidence lacking. The ACR did not make any recommendations regarding surgical interventions—these will be discussed later in this article. The current recommendations assume that the patient has already tried and failed intermittent over-the-counter (OTC) acetaminophen, OTC non-steroidal anti-inflammatory drugs (NSAIDs), and OTC nutritional aides (glucosamine, chondroitin).1
The ACR did not “strongly recommend” any medications for the management of hip OA. Acetaminophen, oral NSAIDs, tramadol, and intra-articular corticosteroid injections are conditionally recommended for arthritis treatment depending on the clinical scenario (Table 1). For example, patients who have a history of coronary artery or peptic ulcer disease may need to be selective about the type of NSAID that is used, avoiding those with higher risks.1
The ACR considers non-pharmacologic measures to be the foundation for hip OA treatment. Land-based or aquatic exercise and weight loss (for those who are overweight) are strongly recommended, and should be tailored to the individual’s abilities and comorbid conditions. Self-management programs to learn more about arthritis and how to manage the disease; manual therapy with supervised exercise; psychosocial interventions; and use of thermal agents (icepacks) and walking aids (such as a cane or walker when needed) are conditionally recommended. There is no recommendation made for exercises to improve balance (tai chi, yoga) or manual therapy alone (Table 2).1
In patients who do not desire surgical treatment or have medical conditions that preclude surgery, the ACR guidelines recommend that physicians consider opioid treatment for patients who fail initial medical management or non-pharmacologic interventions.1,13 Duloxetine (Cymbalta), transcutaneous electrical nerve stimulation, and traditional Chinese acupuncture are not recommended, as there are no large comprehensive studies of their efficacy in hip OA.1
Authors’ Recommendations: Combining Therapies
As with OA of the knee, it is recommended to use multiple modalities in treating OA of the hip as no single modality provides complete relief of symptoms.2 Combining multiple modalities allows for synergy among the different treatments and often provides better pain relief for patients. Figure 1 illustrates the six types of interventions that should be considered for the treatment of hip OA.
Most of these treatments have a small to moderate impact on OA pain; the use of multiple modalities is an intuitive strategy for improving patients’ symptoms. Most of the studies have been performed in knee OA or in a mixed group of both knee and hip OA; therefore, definitive studies on the effects of modalities specific to hip OA are lacking. In considering other treatment options, we have made recommendations based on the best evidence available to date (Table 3).
There is general consensus among all the guidelines supporting the use of acetaminophen, oral NSAIDs, and tramadol.1-4 The ACR cautions that if a patient is prescribed acetaminophen in the full dosage (up to 4,000 mg/d), that patient should be counseled to avoid all other products containing acetaminophen, including OTC cold remedies as well as combination products with opioid analgesics.1
Because of concerns about dose-dependent risk of gastrointestinal, cardiovascular, hematologic, hepatic, and renal adverse events associated with NSAIDs, many prescribers may be nervous about prescribing high doses of these agents to their patients.14 To overcome these concerns, oral NSAID formulations recently have been created that include nitric oxide links to inhibit cyclooxygenase—a class of medications called cyclooxygenase-inhibiting nitric oxide donating drugs. This class of medications may hold promise in the future by causing less gastric toxicity.15
Topical NSAIDs have not been well studied in hip OA; therefore, it is unknown whether they provide similar pain relief to that experienced in other joints.14
Tramadol has been shown to provide pain relief and improved function in patients with OA. It is conditionally recommended by the ACR because side effects are common.16 As noted previously, duloxetine was not recommended by the ACR as there are no large studies in hip OA.1
Injectables provide a fairly convenient method for treatment of OA symptoms, although for hip OA, fluoroscopic or ultrasonic guidance is frequently required. Compliance is good and dosing is fairly convenient. Side effects of injectable medications are uncommon. As noted previously, intra-articular steroids were conditionally recommended by the ACR, whereas no recommendation was made for viscosupplementation.1