Any activity involving repeated movement of the wrist and forearm, or repeated twisting of the wrist coupled with inadequate rest, may cause Tennis elbow. Possible activities include:

• Working with a screw driver

• Painting with a brush

• Hammering

• Scissoring
  

Such activities may cause tiny tears in the muscle fibers and the tendons attaching the muscles of the forearm to the epicondyles. These tears may heal themselves if given sufficient rest but if the activity is vigorous or continued, healing becomes delayed and there is prolonged inflammation and tissue degeneration of the tendons.