Functional and surgical treatments in patients with spinal muscular atrophy (SMA)

Spinal muscular atrophies (SMA type 1, 2, 3) present with various severities according to the motor semeiology related to lesions of the peripheral nervous system (lesions of the anterior horn cells motoneuron or even brain stem). Early motor deficiency causes skeletal deformities responsible for the alteration or even absence of motor skills acquisition. The management of these patients involves several practitioners: pediatric neurologist, pediatric pneumologist, physical medicine and rehabilitation therapist, pediatric orthopedic surgeon, psychologist, physiotherapist, etc. Therefore, this multidisciplinary management must take place in a reference center. This has allowed for improvement of the natural history of SMA. Despite the severity of clinical presentation, especially in SMA type 1 or 2, the functional aspect is always to be taken into account in the first instance. Furthermore, the natural history of the disease is currently being modified by the emergence of innovative therapies that will change the evolution of the disease and its management. Indeed, current treatment objectives are the comfort of installation and the fight against neuro-orthopedic degradation. Although the rise in the number of innovative therapies has led to increased expectancies, such as motor function improvement, practitioners should be aware that these innovative treatments should be balanced against child development and the disease's natural history. Scoliosis surgery is almost systematic in SMA type 2 because of trunk muscular deficiency, especially intercostal muscle insufficiency, and spino-pelvic complex disorder. However, surgical techniques have evolved to become less invasive and more growth friendly in order to follow child development. The final goal of surgery in SMA patients is to obtain a 3-dimensional deformity correction along with a spino-pelvic realignment in order to allow for a comfortable seated position, which is the position of function in these patients, and to allow for better ventilation. Faced with this global approach and innovative therapies, global assessment is warranted not solely in an isolated manner, as is usually the case during hospital stays with traditional scales, but rather during daily activities. This is the case of daily monitoring, which allows for motor skill and activity assessments throughout the day. The principle is to characterize, according to SMA type and treatment, the activity type (standing, seated, walking), duration, intensity and frequency. The ultimate goal would be to identify the variety and occurrence of motor activities, and finally to clarify if the different treatments, including innovative therapies, lead to functional improvement in these patients. © 2020 French Society of Pediatrics. Published by Elsevier Masson SAS. All rights reserved.