The most common spinal deformity, alongside scoliosis, is Kyphosis or ‘C’-shaped curve of the spine. With excessive kyphosis or curvature there is too much forward curve in the spine resulting in a rounded or hunch/hump back appearance, sometimes called slouching or Scheuermann’s disease in juvenile instances. It is classified as either postural – with poor posture causing a smooth curve which can be corrected by the patient - or structural which is caused by an abnormality affecting the bones, intervertebral discs, nerves, ligaments, or muscles. Structural kyphosis may require medical intervention because the patient alone cannot control curve progression. Abnormal kyphotic curves are more commonly found in the thoracic or thoracolumbar spine, although they can be cervical.

Kyphosis is a progressive spinal disorder that can affect children or adults. It can be congenital, postural but also is associated with neuromuscular disorders and result from trauma, tumors, infection, and arthritis. In adults, osteoporosis is a common cause.