Pain in the middle of the back is often felt between the shoulder blades. It may refer pain into the front of the chest, which may be very severe and can restrict when taking a deep breath in.
The ribs attach onto the vertebrae at the back and a restriction of the spine can cause acute pain along the ribs.
These conditions are often very easy to treat, and usually involve freeing the restricted areas to allow inflammation to clear and movement to return.
Sometimes pain felt in this area is referred from somewhere else, usually the neck.