Botulinum toxin injection into the forearm muscles for wrist and fingers spastic overactivity in adults with chronic stroke: a randomized controlled trial comparing three injection techniques.

Objective: To compare the outcome of manual needle placement, electrical stimulation and ultrasonography-guided techniques for botulinum toxin injection into the forearm muscles of adults with arm spasticity.

Design: Randomized controlled trial.

Setting: University hospital.

Subjects: Sixty chronic stroke patients with wrist and fingers spasticity.

Intervention: After randomization into three groups, each patient received botulinum toxin type A in at least two of these muscles: flexor carpi radialis and ulnaris, flexor digitorum superficialis and profundus (no fascicles selection). The manual needle placement group underwent injections using palpation; the electrical stimulation group received injections with electrical stimulation guidance; the ultrasonography group was injected under sonographic guidance. A sole injector was used.

Main Measures: All patients were evaluated at baseline and four weeks after injection.

Outcomes: Modified Ashworth Scale; Tardieu Scale; wrist and fingers passive range of motion.

Results: One month after injection, Modified Ashworth Scale scores improved more in the electrical stimulation group than the manual needle placement group (wrist: P = 0.014; fingers: P = 0.011), as well as the Tardieu angle (wrist: P = 0.008; fingers: P = 0.015) and passive range of motion (wrist: P = 0.004). Furthermore, Modified Ashworth Scale scores improved more in the ultrasonography group than in the manual needle placement group (wrist: P = 0.001; fingers: P = 0.003), as well as the Tardieu angle (wrist: P = 0.010; fingers: P = 0.001) and passive range of motion (wrist: P < 0.001; proximal interphalangeal joints: P = 0.009). No difference was found between the ultrasonography and electrical stimulation groups.

Conclusions: Instrumental guidance may improve the outcome of botulinum toxin injections into the spastic forearm muscles of stroke patients.