A medical student is reviewing the typical progression of motor development in early childhood. Arrange the following gross motor milestones in the chronological order in which they typically emerge in a healthy, full-term infant.
- 1Lifts head and chest while in a prone position
- 2Rolls over from a prone to a supine position
- 3Sits independently without truncal support
- 4Pulls to a standing position holding onto furniture
- 5Walks independently without assistance
Answer
The correct chronological sequence is: Lifting head and chest (2 months), Rolling from prone to supine (4 months), Sitting without support (6 months), Pulling to stand (9 months), and Walking independently (12-15 months).
Gross motor development progresses in a strict cephalo-caudal (head-to-toe) direction. Control begins with the neck (lifting head at 2 months), moves down to the upper trunk and shoulders (rolling over at 4 months), progresses to the lower trunk for core stability (sitting unsupported at 6 months), extends to the pelvis and upper legs (pulling to stand at 9 months), and culminates in full lower extremity integration for balance and ambulation (walking independently at 12 to 15 months).
Step-by-Step Solution
Key Concept
Chronological acquisition of infant gross motor milestones following a cephalo-caudal progression.