Comparison between Botulinum Toxin and Corticosteroid Injection in the Treatment of Acute and Subacute Tennis Elbow: A Prospective, Randomized, Double-Blind, Active Drug-Controlled Pilot Study.

Objective: To compare botulinum toxin type A injection with corticosteroid
injection in the treatment of tennis elbow.
Design: In this prospective, randomized, double-blind, drug-controlled
trial,19 affected elbows of 16 patients were randomly assigned to receive
injection with botulinum toxin type A (Botox group) or triamcinolone
acetonide (steroid group). We used the Visual Analog Scale, pain-free
grip strength, and World Health Organization Quality of Life Brief Questionnaire
to assess the perception of pain, grip strength, and quality of life,
respectively. Measures were performed before and at 4, 8, and 12 wks
after the treatment.
Results: Four weeks after the treatment, the Botox group had smaller
decrease in pain (P 0.02) but greater decrease in grip strength (P
0.01). The difference in grip strength remained significant at 8 wks (P
0.03). No significant differences in quality of life were observed throughout
the study period.
Conclusions: Corticosteroid is superior to botulinum toxin type A in
relieving pain in tennis elbow at 4 wks after injection. Because botulinum
toxin injection did not relieve pain significantly but is associated with
weakness, the muscle weakness caused by botulinum toxin is unlikely to
be the sole mechanism of the pain relief observed in previous studies