Bursitis and tendinitis are both common conditions that cause swelling around muscles and bones. They occur most often in the shoulder, elbow, wrist, hip, knee, or ankle. A bursa is a small, fluid-filled sac that acts as a cushion between a bone and other moving body parts such as muscles, tendons, or skin.
In higher vertebrates, such as reptiles, birds and mammals, there are 12 pairs of cranial nerves. Lower vertebrates, such as fish and amphibians, have 10 pairs of cranial nerves. Continue Reading.
The twelve cranial nerves, the trochlear nerve included, emerge from or enter the skull (the cranium), as opposed to the spinal nerves which emerge from the vertebral column. The trochlear nerve is the only cranial nerve that arises from the back of the brain stem and it follows the longest course within the skull of any of the cranial nerves.