The Concept of "Key Muscles" and the Early Onset of Botulinum Therapy in Spastic Forms of Cerebral Palsy
The botulinum therapy remains the most effective and safe method for reducing local spasticity in patients with cerebral palsy (CP). However, the list of indications for injections of botulinum toxin type A (BTA) in cerebral palsy is limited both in terms of target muscles and the treatment initiation age. In this regard, doctors are guided by the data of clinical studies, reviews and consensuses of experts, which are advisory in nature. One of the most urgent issues in the modern CP botulinum therapy is the evaluation of risks and benefits of initiating injections at an early age (up to 2 years) in order to prevent orthopedic complications and stimulate the optimal motor development of a child. The review analyzes the history of the development of modern approaches to the use of botulinum therapy in cerebral palsy and the tactics of selecting target muscles and doses for multilevel injections. The authors focus on the latest international data on the feasibility and safety of reducing the admissible initiation age for botulinum therapy in cerebral palsy. The results from the studies of the effect of the early initiation of BTA injections on motor development, formation of secondary orthopedic complications in children under 2 years of age, and morphological changes in the neuromotor apparatus in animal experiments are presented. The concept of «key muscles» is considered in detail as one of the possible reference points in the planning of safe and effective early injections.