Recovery of rat muscle size but not function more than 1 year after a single botulinum toxin injection

Abstract

The data demonstrate that, after a single BT-A injection, although gross muscle morphology recovered over a 12-month time period, loss of contractile function did not recover. Muscle Nerve 57: 435-441, 2018.

Muscle volume alterations after first botulinum neurotoxin A treatment in children with cerebral palsy: a 6‐month prospective cohort study

“…This study has found that, at 25 weeks, muscle volume has not fully recovered, consistent with previous animal 9,27 and human research. 11 Previously published data by Barber et al 15 found that, at 52 weeks, injected gastrocnemius showed a 4.8% increase in normalized volume (calculated on the basis of presented fibula lengths) in toxin-naive children with CP.…”

Does cryoneurolysis result in persistent motor deficits? A controlled study using a rat peroneal nerve injury model

“…Thirty 300 g male Lewis rats underwent survival surgery under isoflurane anaesthesia with analgesia provided with preoperative subcutaneous injection of 0.3 mg sustained release buprenorphine (Buprenorphine SR-LAB, ZooPharm, Windsor, Colorado, USA). Common peroneal (fibular) nerves were exposed bilaterally at the proximal lateral margin of the knee joint using a technique previously described 22 23. The fascial sheath overlying the nerve was left intact.…”

“…End points were assessed at 3, 14, 30, 90, and 180 days following treatment, a time frame over 3x longer than that during which a small population of persistent motor deficits were observed 2323.…”

“…End points were assessed at 3, 14, 30, 90, and 180 days following treatment, a time frame over 3x longer than that during which a small population of persistent motor deficits were observed 2323. Briefly, following anaesthesia induction (2% isoflurane, 2.0 L/min), dorsiflexors were activated via the common fibular nerve using a nerve cuff (15V at 100 Hz, 0.3 ms pulse duration and 650 ms train duration), while torque was measured using a custom-designed dynamometer 22.…”

Can botulinum toxin cause chronic muscle weakness?

“…In this issue of Muscle & Nerve, you will find an interesting study entitled "Recovery of Rat Muscle Size but Not Function More Than 1 Year After a Single Botulinum Toxin Injection" by Ward et al 3 In their study, adolescent rats received a single botulinum toxin injection, and muscle anatomy and function were then assessed throughout an 18month period and compared with a saline-injected cohort. A surprising finding was that, 1 year later, after toxin injection, dorsiflexion torque production remained depressed by 25% compared with the contralateral leg, whereas gross morphology had recovered.…”