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Infant: Hypotonia and regression PDF Print E-mail
Written by Administrator   
Wednesday, 27 June 2012 02:19

Case History

T was a 7 m.o. male.  T’s mother paid close attention to the child’s developmental milestones. She noted that he started rolling from back to front at 3 months but he stopped rolling at 4 months. She also noted that during tummy time, T couldn’t keep his head up for long time and got tired quickly. A physical therapist noted hypotonia and lower extremity weakness.

Clinical Pearl: Loss of motor milestones is a red flag for prompt referral to a specialist (consider pediatric neurology).

At the 6-month well-child visit, the PCP was concerned regarding T’s gross motor development. T was not able to bear weight on his legs and slipped through the examiners hands when he was held around the chest. He was referred to a local neurologist who ordered an MRI that was read as abnormal (‘focal areas of pachygyria could be potentially present'). A spinal MRI was also done and was negative. The neurologist sent CK, serum amino acids, and TSH/FT4, all of which were normal. Urine organic acids were pending.


The PCP sent T to a pediatric neurologist at the nearest major medical center for a second opinion. At evaluation at 7 months, T’s fine motor function was normal. Socially, the child was very interactive and playful and verbal. He could hold his head unassisted when held, but he had head lag when pulled up from supine position. He could sit without support when placed into the sitting position, but did not bear weight on legs and did not have much extremity movement. His growth was very good and appropriate for age. Genetic testing confirmed the diagnosis of SMA.