• Signs of Weakness
  • Clinical Evaluation
  • Testing and Referral
  • Resources and Tools
Performing an Exam PDF Print E-mail
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Friday, 04 February 2011 05:25

Examination for signs of proximal muscle weakness includes:

  • Watching for abdominal breathing or accessory muscle use
  • Evaluating for head lag when pulled to sit (also note biceps resistance- failure of child pulling back when pulled to sit)- or inability to voluntarily flex neck when supine
  • Evaluating whether child “slips through the hands” when held suspended (examiner’s hands under the armpits)
  • Stimulating foot and evaluate force of withdrawal movement
  • Watching for difficulty rising from floor (including Gowers maneuver, full or modified)

On exam, look for muscle hypertrophy or atrophy, particularly calves and tongue (calves may also feel abnormally full).

See the “Motor Assessment by Age” surveillance aid for more information.

Other physical findings may help distinguish neuromuscular disease (peripheral cause, such as Duchenne muscular dystrophy) from diseases of the brain (central cause, such as cerebral palsy), as shown in the table that follows. The table that follows shows general guidelines, though evaluation requires use of clinical judgment related to the child’s overall developmental history.


Sign Peripheral Cause Central Cause
Chest size May be small with bell shape Usually normal
Facial movement Often weak “myopathic” with high arched palate Usually normal
Tongue fasciculation May be present, particularly in SMA Absent
Tone Reduced tone Reduced tone or increased tone with scissoring
Deep Tendon Reflexes Decreased or absent Increased, may have clonus

Toe walking



Toe walking




      To view Peripheral signs of weakness click here.

It is important to test for signs of motor weakness over time. If a child does not achieve a motor milestone at the expected time, follow up until the milestone is achieved, or until there is sufficient concern or referral. Ask about and evaluate for signs of motor regression.


Download a pdf of the Surveillance and Referral Aid for Primary Care Providers. This Aid includes assessing weakness by age, clinical evaluation for muscle weakness, guidance on the use of CK testing, and the motor delay algorithm. These materials have been endorsed by the American Academy of Pediatrics.
Last Updated on Thursday, 30 August 2012 15:39

Did you know?

If transaminases (AST and ALT) are elevated, check CK. Since AST/ALT can come from muscle or the liver, while CK comes only from muscle, this test will help localize the child's problem and may prevent unnecessary liver tests.