Botulinum Neurotoxin Injections in Childhood Opisthotonus

Abstract

Opisthotonus refers to abnormal axial extension and arching of the trunk produced by excessive contractions of the paraspinal muscles. In childhood, the abnormal posture is most often related to dystonia in the setting of hypoxic injury or a number of other acquired and genetic etiologies. The condition is often painful, interferes with ambulation and quality of life, and is challenging to treat. Therapeutic options include oral benzodiazepines, oral and intrathecal baclofen, botulinum neurotoxin injections, and deep brain stimulation. Management of opisthotonus within the pediatric population has not been systematically reviewed. Here, we describe a series of seven children who presented to our institution with opisthotonus in whom symptom relief was achieved following administration of botulinum neurotoxin injections.

A Systematic Review of Botulinum Toxin Injection in Pediatric Dystonia

“…Table 1 presents a summary of our findings. Four open-label studies reported outcomes after treatment for dystonia associated with CP, the so-called dyskinetic cerebral palsy (DCP) [13][14][15][16], while others focused on focal dystonia [17,18] or opisthotonos [19]. Three case reports reported outcome measures of patients with a defined genetic condition associated with generalized dystonia: pantothenate kinase-associated neurodegeneration (PKAN) [20,21] and Hallervorden-Spatz syndrome (HSS) [22].…”

“…Most studies reported on patients treated with Onabotulinum toxin type A (Ona BTA) (Botox) [13,16,19,21,24] or Abobotulinum toxin type A (Abo BTA) (Dysport) [17,20,22,23] or both [15], while two studies reported injection of Rimabotulinum toxin type B (Rima BTB) (Myobloc) [14,18]. The BT dose ranged from 4 to 23.8 U/kg for Ona BTA, from 4.8 to 30 U/kg for Abo BTA and from 50 to 200 U/kg for Rima BTB.…”

“…The BT dose ranged from 4 to 23.8 U/kg for Ona BTA, from 4.8 to 30 U/kg for Abo BTA and from 50 to 200 U/kg for Rima BTB. Regarding the injection technique, anatomical markers were used by four authors [13,17,19,24], while ultrasound-assisted injections were used by two researchers [15,18]; two authors used electromyographic muscles identification [14,23], whilst in the other four cases the injection method was not specified [16,[20][21][22].…”

“…For the reporting of treatment outcomes, some studies evaluated motor function recovery based on quantitative motor scales [13,14,[16][17][18]21] or on empirical clinical improvement [19,20,[22][23][24].…”

“…Furthermore, BT injection was found to be devoid of side effects and therefore highly safe. Three open-label studies reported sporadic transient post-injection weakness in a few patients [13,14,19].…”