Clinical Bottom Line
“How should I apply this information?”
An understanding of the developmental trajectory of muscle activation patterns during early functional movements in infants with myelomeningocele (MMC) provides knowledge of what is to be expected over developmental time. Infants with MMC showed highly variable timing of muscle activation during treadmill stepping across the first year, similar to that seen in infants who are developing typically. However, the overall muscle activation for children with MMC was low, particularly during stance, and with time there was minimal change. This information can be used when promoting and implementing an early intervention program and goal setting, taking into consideration the effects of maturation. Knowing the differences in muscle activation quality and quantity in infants with MMC provides the clinician with knowledge to foresee and prevent secondary orthopedic impairments and compensations, which are a significant issue in this patient population. Importantly, these data provide the idea of a developmental “baseline” to gage the effects of intervention on the possible increase in duration of muscle activations for infants and children with MMC.
“What should I be mindful about in applying the information?”
Infants with MMC are extremely diverse in clinical presentation, taking into consideration not only the level of lesion but the involvement of secondary impairments such as hydrocephalus, Arnold Chiari malformation, and orthopedic deformities. To obtain “normative” data from such a varied patient population is understandably difficult. The small sampling of patients for this article included infants with high lumbar to sacral level lesions, and does not describe muscle activation between the groups. We would logically expect that the infants with a lumbar lesion would have significantly less muscle activation than those with a sacral level lesion; depending on the subjects in the study, the overall results may be skewed by their sample. Lastly, longitudinal data were provided for only 4 of the 12 subjects; it is difficult to generalize from this heterogeneous and small sample.
Jill Ordorica, DPT
Children's Hospital Los Angeles
Los Angeles, California
Linda Fetters, PT, PhD
University of Southern California
Los Angeles, California