As mentioned, Jason Kipnis has landed on the 15-day disabled list on Friday as he initiates the healing process for a strained right oblique muscle. He suffered the injury while swinging the bat when he hit into a double-play in the fourth inning against the Angels on Tuesday evening.
Strains of the oblique muscles and their tendons occur when the muscles are most at risk in baseball when the player is involved in movements that extend and twist the trunk of the body. This extension and rotation is required to create force and as the player completes the motion by following through (on a swing, for example) the abdominal muscles flex the trunk and the internal and external muscles on the opposite side counter the trunk rotation.
For example, the batter must create force through rotation in order to generate power. After he strides with the front foot, there is strong tension in the core as the upper body stays back while the lower body moves forward towards the pitcher. Any bio mechanical error during the release of this tension (as the batter swings the bat) can result in a strain of the oblique muscles and their tendons.
As athletes have become bigger and more powerful and movement has become more dynamic, the incidence of injury to the oblique muscles has increased, especially in baseball.
With Kipnis, rest is going to be the major injury management factor for this injury. Healing is a slow process and subject to setbacks because movements of the trunk during activities of daily living can irritate this muscle.
Kipnis, manager Terry Francona and general manager Chris Antonetti all suggested a timetable of three to five weeks for a return to action. This makes sense as these muscles heal by the formation of scar tissue, which is only 70 percent as strong as the tissue it replaces.
According to Zack Meisel of the Cleveland Plain Dealer, Indians manager Terry Francona said: “These types of injuries, we have to let that thing settle down and get all the pain out of there before he can start doing physical activity.”