Hyperkyphosis refers to an excessive curvature of the thoracic spine, commonly referred to as hunchback. A kyphosis angle over 50 degrees is currently the standard for defining hyperkyphosis. Related Definitions Kyphosis Thoracic Spine Editor’s Top Picks Thoracic Kyphosis: Forward Curvature of the Upper Back Thoracic Spine Anatomy and Upper Back Pain All About the C7-T1 Spinal Segment (Cervicothoracic Junction)