Effect and Safety of Local Injection of Botulinum Toxin Type B Against Digital Ulcer in Systemic Sclerosis

BTX-B (E2014, Eisai, NerBloc®) was injected subcutaneously from the palmar side into seven locations around interphalangeal metacarpophalangeal joints, targeting the neurovascular bundles just proximal to the A1 pulley (the radial and ulnar sides of the first finger, the radial side of second finger, the ulnar side of the fifth finger and between the second to fifth fingers). Three locations between the second and third fingers, the third and fourth fingers, and the fourth and fifth fingers were injected with 400 U (0.2 ml) of BTX-B. In addition, the radial and ulnar sides of the first finger, the radial side of the second finger, and the ulnar side of the fifth finger were injected with half a dose of BTX-B (200 units; 0.1 ml). A total of 2000 U (1.0 ml) of BTX-B was injected into one hand. Injections were performed using a 30-gauge needle.

Saline solution was injected subcutaneously from the palmar side into seven locations around interphalangeal metacarpophalangeal joints, targeting the neurovascular bundles just proximal to the A1 pulley (the radial and ulnar sides of the first finger, the radial side of second finger, the ulnar side of the fifth finger and between the second to fifth fingers). Three locations between the second and third fingers, the third and fourth fingers, and the fourth and fifth fingers were injected with saline (0.2 ml). In addition, the radial and ulnar sides of the first finger, the radial side of the second finger, and the ulnar side of the fifth finger were injected with half a dose of saline (0.1 ml). A total of 1.0 ml of saline was injected into one hand. Injections were performed using a 30-gauge needle.