• Inflammatory Disorders
• Shoulder & Elbow Conditions
• Rheumatology Clinical Trials

• Inflammatory Disorders
• Shoulder & Elbow Conditions
• Rheumatology
• Rheumatology Clinical Trials

Platelet-rich plasma (PRP) was not more effective in relieving the pain due to epicondylitis (tennis elbow) compared with saline when each was delivered by ultrasound-guided injection. However, both groups showed significant decreases in pain scores from baseline at 6 months, suggesting to investigators that tendon stimulation may be the actual mechanism behind the observed lesion repair and improvement in pain symptoms.

Patrick Le Goux, MD, Rheumatology, Hôpitaux Universitaires Paris Ile-de-France Ouest, Boulogne-Billancourt, France, noted that the significant decrease in pain scores observed over the course of the trial in both groups was exciting and suggested that the healing process may actually be stimulated by the injection process, a technique known as “prolotherapy.”

Prof. Le Goux explained that local corticosteroid injections represent a standard of care for epicondylitis but may actually impair the healing process [Coombes BK et al. JAMA 2013].

Prof. Le Goux noted that intratendinous injections of PRP containing growth factors have been proposed to aid tendon repair [Peerbooms JC et al. Am J Sports Med 2010], and the injection technique has been reported to be augmented by ultrasound guidance [Chiavaras MM, Jacobson JA Semin Musculoskelet Radiol 2013].

Prof. Le Goux and colleagues conducted this prospective, double-blind, placebo-controlled randomized trial from 2011 to 2012. Patients with epicondylitis lasting 3 months or fewer were enrolled. Other potential causes of pain were ruled out, and features of epicondylitis were confirmed by magnetic resonance imaging, ultrasound, or both. Patients with previous corticosteroid infiltration were excluded.

Patients received 2 ultrasound-guided injections of either PRP or saline solution at 4-week intervals and were monitored by an independent clinical evaluator, who was blinded to the treatment, at baseline and 1-, 3-, 6-, and 12-month time points. PRP was obtained from each patient, treated by centrifugation only to concentrate the material, and reinjected into the injured joint of the same patient. Injections were done in a blinded and identical manner for both treatments by using a dual-chamber syringe that penetrated 3 layers into the tendon to target the lesion without entering it.

Each treatment group comprised 25 patients following randomization; however, 3 patients in each arm withdrew from the study within 6 months, due to reasons unrelated to treatment. Patients were evaluated at 6 months for the decrease in pain score from baseline (primary evaluation criteria) using a visual analog scale (VAS; range, 0 to 10). At 6 months, pain scores were reduced by 54.7% with PRP versus 63.6% with saline (p=0.24).

Secondary endpoints included assessment of pain (yes/no) during isometric contraction of the extensor carpi radialis brevis and the extensor digitorum communis and measurement of the degree of pain using the Roles and Maudsley score (range, 1 to 4). Mean baseline Roles and Maudsley scores were 6.8 (±0.8) in the PRP group and 7 (±1) in the saline group; a mean reduction of 1.5 points was observed in both groups at 12 months.

No significant differences between treatment groups were observed at 6 or 12 months in either primary or secondary criteria.

However, significant patient benefit was observed; both groups showed a 50% reduction of pain scores within 3 to 6 months. At 6 and 12 months, respectively, 34% and 66% of all patients were asymptomatic, defined as VAS scores of 1 or less. The proportion of patients with persistent pain at 12 months was equivalent at 23.8% in both groups. No adverse events were reported.

Prof. Le Goux attributed the pain reduction observed with both treatments to the stimulating role of ultrasound-guided intratendinous injections, or prolotherapy, on the process of tendon repair. He further commented that the study was limited by not including a group of patients with epicondylitis who received no treatment so that the pain reduction observed over time with natural healing could be compared with the PRP and saline results.

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