What is the aim of this review?
The aim of this Cochrane review was to find out if acupuncture improves pain and function in people with hip osteoarthritis. We collected and analyzed all relevant studies to answer this question and found 6 relevant studies with 413 people.
Key messages
In people with hip osteoarthritis, at close to 8 weeks:
- Acupuncture probably results in little or no difference in pain or function compared to sham acupuncture.
- Acupuncture plus routine primary physician care may improve pain and function compared to routine primary physician care alone.
- We are uncertain whether acupuncture improves pain and function compared to either advice plus exercise or NSAIDs.
- We are uncertain whether acupuncture plus patient education improves pain or function compared to patient education alone.
What was studied in the review?
Osteoarthritis (OA) is a disease of the joints, and the hip is the second most commonly affected joint. Some drug therapies commonly used for treating hip OA have a risk for side effects. Therefore, it is important to evaluate the effectiveness and safety of non-drug therapies, including acupuncture. According to traditional acupuncture theory, stimulating the appropriate acupuncture points in the body by inserting very thin needles can reduce pain or improve function.
In clinical trials, sham acupuncture is intended to be a placebo for true acupuncture. In sham acupuncture, the patient believes he or she is receiving true acupuncture, but the needles either do not penetrate the skin or are not placed at the correct places on the body, or both. The purpose of the sham acupuncture control is to determine whether improvements from acupuncture are due to patient beliefs in acupuncture, rather than the specific biological effects of acupuncture. However, there is controversy about sham acupuncture. It is believed that some types of sham acupuncture may produce effects that are similar to the effects of true acupuncture.
What are the main results of the review?
After searching for all relevant trials published up to March 2018, we found 6 trials with 413 people. All trials included primarily older participants, with mean age range from 61-67 years, and mean duration of hip OA pain from 2-8 years. About two-thirds of participants were women.
Two of the included trials compared acupuncture to sham acupuncture. These two sham-controlled trials were small-sized, but were well-designed and of generally high methodological quality. The sham acupuncture control interventions were judged believable, but each sham acupuncture intervention was also judged to have a risk of weak acupuncture-specific effects. This was due to placement of non-penetrating needles at the correct acupuncture points in one trial, and use of penetrating needles not inserted at the correct points in the other. A meta-analysis of these two trials gave moderate-quality evidence of little or no effect in reduction in pain or improvement in function for true acupuncture relative to sham acupuncture. People who received true acupuncture had slight and non-significant improvements on both pain and function outcomes (2 point greater improvement on a scale of 0-100 for each), compared to those people who received sham acupuncture. Due to the small sample size in the studies the confidence intervals include both the possibility of moderate benefits and the possibility of no effect of acupuncture. A quality-of-life pooled outcome could not be estimated.
One unblinded trial gave low quality evidence that acupuncture as an addition to routine primary physician care is associated with benefits on pain, function, and physical component-quality of life (but not mental component-quality of life). However, these reports of benefits in trial participants who received the additional acupuncture are likely due at least partially to their a priori expectations of a benefit, or their preference to get randomized to acupuncture. Evidence from the 3 other unblinded trials was uncertain.
Possible side effects of acupuncture treatment included minor bruising and bleeding at the site of needle insertion, which were reported in 2 trials. Four trials reported on adverse events, and none reported any serious adverse events attributed to acupuncture. No trial reported on radiographic joint changes.
How up-to-date is this review?
We searched for studies that had been published up to 18 March 2018.
Acupuncture probably has little or no effect in reducing pain or improving function relative to sham acupuncture in people with hip osteoarthritis. Due to the small sample size in the studies, the confidence intervals include both the possibility of moderate benefits and the possibility of no effect of acupuncture. One unblinded trial found that acupuncture as an addition to routine primary physician care was associated with benefits on pain and function. However, these reported benefits are likely due at least partially to RCT participants' greater expectations of benefit from acupuncture. Possible side effects associated with acupuncture treatment were minor.
Hip osteoarthritis (OA) is a major cause of pain and functional limitation. Few hip OA treatments have been evaluated for safety and effectiveness. Acupuncture is a traditional Chinese medical therapy which aims to treat disease by inserting very thin needles at specific points on the body.
To assess the benefits and harms of acupuncture in patients with hip OA.
We searched Cochrane CENTRAL, MEDLINE, and Embase all through March 2018.
We included randomized controlled trials (RCTs) that compared acupuncture with sham acupuncture, another active treatment, or no specific treatment; and RCTs that evaluated acupuncture as an addition to another treatment. Major outcomes were pain and function at the short term (i.e. < 3 months after randomization) and adverse events.
We used standard methodological procedures expected by Cochrane.
Six RCTs with 413 participants were included. Four RCTs included only people with OA of the hip, and two included a mix of people with OA of the hip and knee. All RCTs included primarily older participants, with a mean age range from 61 to 67 years, and a mean duration of hip OA pain from two to eight years. Approximately two-thirds of participants were women. Two RCTs compared acupuncture versus sham acupuncture; the other four RCTs were not blinded. All results were evaluated at short term (i.e. four to nine weeks after randomization).
In the two RCTs that compared acupuncture to sham acupuncture, the sham acupuncture control interventions were judged believable, but each sham acupuncture intervention was also judged to have a risk of weak acupuncture-specific effects, due to placement of non-penetrating needles at the correct acupuncture points in one RCT, and the use of penetrating needles not inserted at the correct points in the other RCT. For these two sham-controlled RCTs, the risk of bias was low for all outcomes.
The combined analysis of two sham-controlled RCTs gave moderate quality evidence of little or no effect in reduction in pain for acupuncture relative to sham acupuncture. Due to the small sample sizes in the studies, the confidence interval includes both the possibility of moderate benefit and the possibility of no effect of acupuncture (120 participants; Standardized Mean Difference (SMD) -0.13, (95% Confidence Interval (CI) -0.49 to 0.22); 2.1 points greater improvement with acupuncture compared to sham acupuncture on 100 point scale (i.e., absolute percent change -2.1% (95% CI -7.9% to 3.6%)); relative percent change -4.1% (95% CI -15.6% to 7.0%)). Estimates of effect were similar for function (120 participants; SMD -0.15, (95% CI -0.51 to 0.21)). No pooled estimate, representative of the two sham-controlled RCTs, could be calculated or reported for the quality of life outcome.
The four other RCTs were unblinded comparative effectiveness RCTs, which compared (additional) acupuncture to four different active control treatments.
There was low quality evidence that addition of acupuncture to the routine primary care that RCT participants were receiving from their physicians was associated with statistically significant and clinically relevant benefits, compared to the routine primary physician care alone, in pain (1 RCT; 137 participants; mean percent difference -22.9% (95% CI -29.2% to -16.6%); relative percent difference -46.5% (95% CI -59.3% to -33.7%)) and function (mean percent difference -19.0% (95% CI -24.41 to -13.59); relative percent difference -38.6% (95% CI -49.6% to -27.6%)). There was no statistically significant difference for mental quality of life and acupuncture showed a small, significant benefit for physical quality of life.
The effects of acupuncture compared with either advice plus exercise or NSAIDs are uncertain.
We are also uncertain whether acupuncture plus patient education improves pain, function, and quality of life, when compared to patient education alone.
In general, the overall quality of the evidence for the four comparative effectiveness RCTs was low to very low, mainly due to the potential for biased reporting of patient-assessed outcomes due to lack of blinding and sparse data.
Information on safety was reported in four RCTs. Two RCTs reported minor side effects of acupuncture, which were primarily minor bruising, bleeding, or pain at needle insertion sites. Four RCTs reported on adverse events, and none reported any serious adverse events attributed to acupuncture.