The trachea bifurcates, or divides, into two branches at its most distal portion and forms the bronchi. The bifurcation is reinforced by a cartilaginous plate called the carina. Like the trachea, each bronchus is made up of cartilaginous rings to keep the lumen open as it goes into the lung. As the branches get smaller, they are called secondary bronchi and segmental (or tertiary) bronchi.
Pins and Needles - Paraesthesia. The most common cause of pins and needles is a moderately pinched nerve. Pins and needles is referred to as paraesthesia in the medical community. Did you know that feeling pins and needles can actually be a worse sign than having pain in your arm or leg.
Leg paresthesia is a sensation of tingling (feeling of âpins and needlesâ) or burning in the leg that occurs without stimulation. It can result from a previous leg injury or pressure on a nerve in the leg. Other causes include damage to nerves in the leg from exposure to extreme heat or cold or to toxic compounds.