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.
Give your baby lots of tummy time as well so she can practice pushing up and strengthening her abdominal muscles, which will also help her to eventually pull up and stand. Most babies start pulling up on their own and then cruising around furniture between 9 and 12 months. If your baby doesn't seem to be making any progress over the next few weeks or months, express your concerns to your pediatrician, who may refer you to a physical therapist to help boost your baby's motor skills. Copright 2009 Meredith Corporation.