A partial tear with or without instability or looseness is considered moderate. A severe sprain implies a complete or near complete tear of tendon fibers that results in looseness or instability at the joint. A sprain is a damaged ligament . Ligaments attach bone to bone. A strain is an injury to a muscle or tendon .
Tendons connect muscle to bone.
Tendonitis is an inflammation of the muscle, tendon, and or bone insertion site. Cramps are characterized by the sudden onset of moderately severe to incapacitating pain in the muscle belly, and may progress to involve other adjacent muscle groups. The first treatment consists of immediate rehydration with a fluid containing electrolytes. After beginning rehydration, further treatment should consist of grasping and applying pressure to the muscle belly and immediately putting the muscle on stretch until the cramp resolves. Flexing the foot toward the head for example, would stretch the calf muscle, whereas a thigh cramp would be treated by flexing the knee, bringing the foot to the buttocks.