OnabotulinumtoxinA Injection for Poststroke Upper-Limb Spasticity: Guidance for Early Injectors From a Delphi Panel Process

Abstract

Background: OnabotulinumtoxinA reduces muscle hypertonia associated with poststroke spasticity (PSS). PSS manifests as several common postures.

Objective: To define treatment paradigms for PSS upper-limb common postures.

Design: Modified Delphi method.

Setting: Expert panel.

Participants: Ten injectors experienced in the treatment and clinical research of PSS (physiatrists and neurologists) were invited to participate in the Delphi panel.

Methods: The Delphi panel reviewed an electronic worksheet with PSS upper-limb postures to define onabotulinumtoxinA treatment paradigms (Round 1). During Round 2, panel members discussed in person Round 1 results and voted until consensus (≥66% agreement). Recommendations were geared toward those with new or early injection experience.

Main outcome measurements: Expert consensus on onabotulinumtoxinA treatment parameters for PSS including muscles to inject, dose per muscle and posture, and treatment adjustments for suboptimal response.

Results: For each posture, consensus was reached on targeted subsets of muscles. Doses ranged for individual muscles (10-100 U) and total doses per posture (50-200 U). An onabotulinumtoxinA dilution 50 U/mL (2:1 dilution ratio) was considered most appropriate; dilution ratios of 1:1 to 4:1 may be appropriate in some circumstances. The majority (89%) of panel members would increase the dose and/or the number of muscles treated for a suboptimal response to onabotulinumtoxinA. The panel identified 3 common aggregate upper-limb postures: (1) adducted shoulder + flexed elbow + pronated forearm + flexed wrist + clenched fist; (2) flexed elbow + pronated forearm + flexed wrist + clenched fist; and (3) flexed wrist + clenched fist. The recommended starting dose per aggregate was 300 U, 300 U, and 200 U, with a total maximum dose of 400 U, 400 U, and 300 U, respectively. Localization guidance techniques were considered essential for all postures.

Conclusions: Consensus on common muscles and onabotulinumtoxinA treatment paradigms for postures associated with upper-limb PSS was achieved via a modified Delphi method. The purpose of this analysis is to educate early onabotulinumtoxinA injectors rather than provide an evidence-based review.

Level of evidence: V.