The lumbrical muscles do not attach to the proximal phalanx directly, but rather connect the tendons of flexor digitorum profundus (below, ie volar) to the extensor tendons (above, ie dorsal) and produce flexion by pulling on the extensor tendons as they pass over the proximal phalanx.
By the time they are 12 months old, most babies can weigh three times what they weighed at birth and gain about an inch per month in length. The average infant at one year may be between 2630 inches long. Social and Emotional Development-Infants respond when you say their name. They begin to fear strangers.
Baby milestone - pulling up to a stand. Pulling himself up to a standing position is one of the first signs that your baby is ready to learn... Pulling himself up to a standing position is one of the first signs that your baby is ready to learn to walk, so it's a major baby milestone. This not only shows walking readiness but lets you know that your baby has the proper strength for walking in his legs and trunk. When it happens: Usually babies will pull themselves up to a standing position somewhere between the age of 9 to 10 months. How to help it happen: You can help encourage your baby to pull himself up by allowing plenty of unbound time - i.e. don't always have your baby in a baby seat or stroller.