The need for early diagnosis Footnote 1


  • Treatment and management strategies may delay disease progression and complications Footnote 2

  • Disease management strategies may delay loss of ambulation and enable patients to maintain their way of life for as long as possible Footnote 3 Footnote 4

  • Expected increased life span with early access to multidisciplinary care Footnotes Footnotes Footnotes 3,5

  • Access to genetic counselling and family planning Footnote 3

  • Female relatives can find out their carrier status Footnote 3

  • Access to emerging therapies and clinical trials Footnote 2

0–6 Months

Baby younger than six months
0–6 Months
No head control at 2 months Footnote 1 Footnote 2
  • At 2 months, infant should lift head and chest in prone position Footnote 1

  • Evaluate pull-to-sit with attention to head lag; if a child has head lag at 4 months, evaluate other age-appropriate motor milestones (e.g. rolling over) and re-evaluate in 1 month. If child is still not age-appropriate, CK test and referral are recommended Footnote 3 Footnote 4

Not making sounds at 4 months Footnote 2
  • At 4 months, most babies have begun to babble and copy sounds they hear

Not reaching or grasping by 6 months Footnotes Footnotes Footnotes Footnotes 1,2,4
  • At 6 months, most babies show curiosity about things around them and try to grab things that are out of reach; they have usually begun to pass things from one hand to the other at this stage

Not rolling over by 6 months Footnotes Footnotes Footnotes Footnotes 1,2,4
  • At 4 months, most infants are able to roll over prone to supine, and at 6 months roll over supine to prone Footnote 1

6–18 Months

Baby older than six months but younger than eighteen months
6–18 Months
Not sitting independently at 9 months Footnote 1 Footnote 2
  • At 9 months, infants should sit well without support. Assess ability to achieve and maintain a sitting position: if the child is not sitting independently by 7 months or able to get into a sitting position by 9 months, CK should be measured Footnote 1 Footnote 2

Not crawling by 9–15 months Footnotes Footnotes Footnotes 3–5
Not speaking first words by 12 months Footnote 4
  • By 12 months, most infants are able to say simple words such as “mama” and “dada” and try to repeat words said by their caregiver Footnote 14

Difficulty rising to stand by 18 months Footnotes Footnotes Footnotes Footnotes 1,2,4
  • Watch for independent rise from floor from a supine position after child can walk well without assistance. Watch to see if child rises by putting hands on knees or thighs, or cannot rise without pulling up Footnote 4
Not walking well by 16–18 months Footnotes Footnotes Footnotes Footnotes Footnotes Footnotes Footnotes 1,4,7
  • At 18 months, the toddler should sit, stand and walk independently. Footnote 7 If the child is not walking well at 18 months or has any regression, CK should be measured and the child referred to a paediatric neurologist Footnote 1

2–3 Years

Child between two and three years
2–3 Years
Gowers’ sign from approximately 2 years old Footnote 1
Not walking smoothly at 2 years old (tip-toe walking) Footnote 1
Not jumping at 2 years old Footnote 2
Difficulty running or climbing at 3 years old Footnote 2 Footnote 3
  • Particularly note the quality of running, especially if there are other motor concerns

Not speaking in sentences at 3 years old Footnote 3
  • By 3 years old, most children can name most familiar things, say their first name, age and sex, and words like “I,” “me,” “we,” and “you”, talk well enough for strangers to understand most of the time, and carry on a conversation using 2 to 3