This is called as Scheuermann's disease. This condition usually manifests in second decade. The patient usually complains of intermittent back pain
. It can lead to kyphotic deformity
(increased curvature of back). Majority of the patients do not require any active treatment. It usually settles by skeletal maturity (17-18yrs). You need to do back extension and abdominal muscle strengthening exercises. If pain is severe then over-the counter available pain medications can be taken.
and surgery and indicated for severe deformities and the progressive ones