A randomized controlled trial of acupuncture for osteoarthritis of the knee: effects of patient-provider communication

Abstract

Objective: There is conflicting evidence on the efficacy of traditional Chinese acupuncture (TCA), and the role of placebo effects elicited by acupuncturists' behavior has not been elucidated. We conducted a 3-month randomized clinical trial in patients with knee osteoarthritis to compare the efficacy of TCA with sham acupuncture and to examine the effects of acupuncturists' communication styles.

Methods: Acupuncturists were trained to interact in 1 of 2 communication styles: high or neutral expectations. Patients were randomized to 1 of 3 style groups, waiting list, high, or neutral, and nested within style, TCA or sham acupuncture twice a week over 6 weeks. Sham acupuncture was performed in nonmeridian points with shallow needles and minimal stimulation. Primary outcome measures were Joint-Specific Multidimensional Assessment of Pain (J-MAP), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and satisfaction scores.

Results: Patients (n = 455) received treatment (TCA or sham) and 72 controls were included. No statistically significant differences were observed between TCA or sham acupuncture, but both groups had significant reductions in J-MAP (-1.1, -1.0, and -0.1, respectively; P < 0.001) and WOMAC pain (-13.7, -14, and -1.7, respectively; P < 0.001) compared with the waiting group. Statistically significant differences were observed in J-MAP pain reduction and satisfaction, favoring the high expectations group. In the TCA and sham groups, 52% and 43%, respectively, thought they had received TCA (κ = 0.05), suggesting successful blinding.

Conclusion: TCA was not superior to sham acupuncture. However, acupuncturists' styles had significant effects on pain reduction and satisfaction, suggesting that the analgesic benefits of acupuncture can be partially mediated through placebo effects related to the acupuncturist's behavior.

Trial registration: ClinicalTrials.gov NCT00059345.

Figure 1. Study Design

For the first half of the trial half of the acupuncturists were randomly allocated to the high expectations communication style and the other half to the neutral style. In the second half the acupuncturists switched communication styles.

Figure 2. Acupuncture points

TCA. The following points were selected: Xi Yan, He Ding, GB 34, SP 6, SP 9, Ear-Knee, 1-2 tender Ashi points proximal to the knee. Filiform needles, 34 gauge, 1 or 1.5 cun, were used except for Ear- Knee in which 36 gauge, 0.5 cun, needles were used. The depth of insertion was 0.2-1.2 cun depending on tolerance. TENS was applied to outer Xi Yan (positive) and inner Xi Yan (negative), and SP 9 (positive) and SP 6 (negative). Sham acupuncture. Needles were inserted at sham points not relevant to the knee, located in between meridians: AC-LE-1, 1.0 cun below and 0.5 cun lateral to ST 36; AC-LE-2,1.0 cun lateral and 1.0 cun above ST 40; AC-LE-3, above the superior-lateral border of the patella, 1.0 cun lateral to the stomach meridian; AC-LE-4, 4.0 cun above the superior-lateral border of the patella, 1.0 cun lateral to the stomach meridian. An arm point, SI 7 was used along with AC-UE-1, located in the middle of SI 5 and SI 8 points. The needles used in the sham procedure were thinner, shorter, and less deeply inserted than in TCA: 36 gauge, 1.0 cun needles 0.2-0.5 cun deep. The TENS unit was connected to SI 7 (positive) and AC-UE-1 (negative), and AC-LE-1 (positive) and AC-LE-2 (negative).