What is the most significant risk factor for clubfoot?

Choice A reason:

The newborn has hypotonia. This is not a specific sign of brachial plexus injury, as hypotonia can have many other causes, such as genetic disorders, infections, or brain damage.

Hypotonia is a general term for low muscle tone or weakness, which can affect the whole body or specific parts.

Choice B reason:

The newborn does not demonstrate the Moro reflex. This is a sign of brachial plexus injury, especially if it affects only one arm. The Moro reflex is a startle response that causes the baby to throw out the arms and legs, then curl them in when startled. A brachial plexus injury can impair the nerve function in the shoulder, arm, or hand, leading to decreased movement or sensation in the upper extremity. If the baby does not show the Moro reflex on one side, it may indicate damage to the upper brachial plexus nerves (C5-C7), also known as Erb's palsy.

Choice C reason:

The newborn cries continually. This is not a specific sign of brachial plexus injury, as crying can have many other causes, such as hunger, discomfort, or colic. Crying is a normal way for babies to communicate their needs and feelings. Crying does not necessarily indicate pain from a brachial plexus injury, as infants' nerves behave differently from adults' and they may not experience much pain from this condition.

Choice D reason:

The newborn has tremors. This is not a specific sign of brachial plexus injury, as tremors can have many other causes, such as cold temperature, low blood sugar, or withdrawal from maternal medications. Tremors are involuntary movements of the muscles that can affect the whole body or specific parts. Tremors do not necessarily indicate nerve damage from a brachial plexus injury, as this condition usually causes weakness or paralysis of the affected muscles.

Choice A reason:

Holding the newborn vertically, allowing one foot to touch the crib surface, will elicit the stepping reflex, not the Moro reflex. The stepping reflex is when the newborn makes stepping movements when held upright with one foot touching a flat surface.

Choice B reason:

Turning the newborn's head quickly to one side will elicit the tonic neck reflex, not the Moro reflex. The tonic neck reflex is when the newborn assumes a "fencing”. position, with the arm and leg extended on the side to which the head is turned and the opposite arm and leg flexed.

Choice C reason:

Performing a sharp hand clap near the infant will elicit the Moro reflex, also known as the startle reflex. The Moro reflex is when the newborn responds to a sudden loss of support or a loud noise by extending and abducting the arms, spreading the fingers, and then bringing the arms together and crying.

Choice D reason:

Placing a finger at the base of the newborn's toes will elicit the Babinski reflex, not the Moro reflex. The Babinski reflex is when the newborn fans out the toes and dorsiflexes the big toe when the sole of the foot is stroked.