Pain in the brachioradialis muscle, which runs from the inside of the wrist down the forearm to the upper arm, can occur for one of several common reasons. The culprit may be a sudden injury, such as can occur from trauma or from pushing the muscle beyond its capacity. Brachioradialis pain can also be the result of overuse, such as when a person has a job that requires repetitive movements using the muscle. It can also come from pressure on the nerves in some parts of the cervical spine, which run down the arm to the brachioradialis, or as referred pain from the other nearby muscles.
An injury that damages or strains the muscle is a common cause of brachioradialis pain. Blunt trauma from a blow or fall can damage muscle tissue. The muscle could be pulled or even torn if it is strained beyond what it is physically capable of, for example if one tries to lift something much heavier than one is capable of. A strain or pull can also occur if the muscle is overextended beyond its natural range. These types of injuries can cause acute pain initially that often then progresses to more constant pain along with swelling, stiffness, and tenderness.
Overuse is also frequently the cause of brachioradialis pain. People who work in jobs that require them to use their arms in repetitive motions, particularly when lifting, twisting, or holding objects may tend to have elbow and forearm pain associated with the brachioradialis and surrounding muscles. Those who play sports such as tennis or racquetball may also have problems in this area. This can be particularly problematic if the person is unable to stop the offending behavior because it is part of their livelihood.
Sometimes brachioradialis pain does not originate in the muscle itself, but rather comes from problems in other areas. Nerves originating from the C5 and C6 vertebrae in the cervical spine run to the radial nerve, which then extends nerve fibers to the brachioradialis. If there is an injury or damage to the spine that puts pressure on the nerve roots in this area, you may feel pain and spasm in your forearm. Brachioradialis pain can also be referred pain from problems in other nearby muscles, such as the supinator and pronator muscles.