Objectives: To assess whether prolo , an injection-based , improves elbow pain, grip strength, and extension strength in patients with lateral epicondylosis.

Setting: Outpatient Sport Medicine clinic.

Study Design: Double-blind randomized controlled trial.

Participants: Twenty-four adults with at least 6 months of refractory lateral epicondylosis.

Intervention: Prolo participants received injections of a solution made from 1 part 5% sodium morrhuate, 1.5 parts 50% dextrose, 0.5 parts 4% lidocaine, 0.5 parts 0.5% sensorcaine and 3.5 parts normal saline. Controls received injections of 0.9% saline. Three 0.5-mL injections were made at the supracondylar ridge, lateral epicondyle, and annular ligament at baseline and at 4 and 8 weeks.

Outcome Measures: The primary outcome was resting elbow pain (0 to 10 Likert scale). Secondary outcomes were extension and grip strength. Each was performed at baseline and at 8 and 16 weeks. One-year follow-up included pain assessment and effect of pain on activities of daily living.

Results: The groups were similar at baseline. Compared to Controls, Prolo subjects reported improved pain scores (4.5 ± 1.7, 3.6 ± 1.2, and 3.5 ± 1.5 versus 5.1 ± 0.8, 3.3 ± 0.9, and 0.5 ± 0.4 at baseline and at 8 and 16 weeks, respectively). At 16 weeks, these differences were significant compared to baseline scores within and among groups (P < 0.001). Prolo subjects also reported improved extension strength compared to Controls (P < 0.01) and improved grip strength compared to baseline (P < 0.05). Clinical improvement in Prolo group subjects was maintained at 52 weeks. There were no adverse events.

Conclusions: Prolo with dextrose and sodium morrhuate was well tolerated, effectively decreased elbow pain, and improved strength testing in subjects with refractory lateral epicondylosis compared to Control group injections.