Efficacy of periosteal stimulation for chronic pain associated with advanced knee osteoarthritis: a randomized,...

Because of morbidity associated with painful knee osteoarthritis (OA) and commonly prescribed analgesics, patients often pursue complementary and alternative modalities (eg, acupuncture). Clinical trials have demonstrated modest therapeutic efficacy of traditional Chinese acupuncture for knee OA pain, and patients with advanced disease have largely been excluded. We have previously demonstrated preliminary short-term tolerability and efficacy of periosteal stimulation therapy (PST) (ie, electrical stimulation of the periosteum facilitated by acupuncture needles) for older adults with advanced knee OA.

This study evaluated the sustained efficacy of PST and boosters for treating chronic pain with advanced knee OA.

One hundred ninety participants age >50 years with Kellgren-Lawrence grade 3 or 4 knee OA and chronic pain were randomized to (1) PST (once a week for 10 weeks) followed by PST boosters for 6 months (once every 2 weeks 2 times, then once a month), (2) control PST (ie, periosteal needles and brief electrical stimulation of control points) once a week for 10 weeks, or (3) PST for 10 weeks followed by control PST boosters for 6 months. Change in the Western Ontario and McMaster Universities Osteoarthritis Index pain score immediately after the 10-week intervention and at 6-month follow-up (9 months after baseline) was the primary outcome. OMERACT-OARSI (Outcome Measures in Rheumatology Clinical Trials-Osteoarthritis Research Society International) criteria also were evaluated. Secondary measures of outcome included (1) physical performance (Short Physical Performance Battery, gait speed, Timed Up and Go, and timed stair climb); (2) psychological factors (depressive symptoms measured with the Center for Epidemiologic Studies-Depression scale, coping measured with the catastrophizing subscale of the Coping Strategies Questionnaire, and self-efficacy measured with the Arthritis Self-Efficacy Scale); (3) health-related quality of life measured with the Medical Outcomes Study 36-Item Short-Form Health Survey; (4) rescue pain medication use tracked with diaries; and (5) health care utilization and interim physical activity were monitored via monthly telephone calls.

After adjustment for pain at baseline, the PST and control booster did not differ from controls at 10 weeks (difference, 1.3; 95% CI, -0.10 to 2.8; P = 0.0683) or 9 months (difference, 1.1; 95% CI, -0.32 to 2.6; P = 0.13). The PST and PST booster group had similar improvement compared with controls at 10 weeks (baseline adjusted difference, 1.1; 95% CI, -0.34 to 2.5; P = 0.1369) but significantly more improvement at 9 months (baseline adjusted difference, 1.5; 95% CI, 0.069 to 3.0; P = 0.0401). Baseline depressive symptoms, low self-efficacy, higher difficulty performing daily activities, and greater knee stiffness predicted a lower likelihood of response.

PST plus PST boosters in patients age >50 with advanced knee OA were well-tolerated and modestly reduced pain. ClinicalTrials.gov identifier: NCT00865046.