Kyphosis is a progressive spinal disorder that can affect children or adults. This disorder may cause a deformity described as humpback or hunchback. Kyphosis can be in the form of hyperkyphosis or sharp angular gibbus deformity (see 'Gibbus Deformity' below). Abnormal kyphotic curves are more commonly found in the thoracic or thoracolumbar spine, although they can be cervical.
Postural and Structural Kyphosis
Kyphosis is classified as either postural or structural. Postural means the kyphosis is attributed to poor posture, usually presenting a smooth curve, which can be corrected by the patient. Structural kyphosis is caused by an abnormality affecting the bones, intervertebral discs, nerves, ligaments, or muscles. Kyphosis with a structural pathology may require medical intervention because the patient alone cannot control curve progression.
Gibbus Deformity
A gibbus deformity is a form of structural kyphosis. The posterior (from behind) curve presents sharply angled; the curvature is not smooth. This deformity may result in a humpback found to be more prominent when bending forward.
Hyperkyphosis
This term is used to describe 'excessive' (hyper) curvature exceeding the normal range. Hyperkyphosis occurs in the thoracic spine. In adults, osteoporosis is a common cause often involving several vertebrae.
Congenital
Congenital means the disorder is found at birth. Congenital kyphosis is a structural abnormality.
Scheuermann's Disease
Scheuermann's Disease is juvenile (adolescent) thoracic kyphosis. Although the cause is unknown, it may be familial. This disease can cause decreased intervertebral disc space and vertebral wedging resulting in an excessive curve described as stiff or rigid. The classic definition of Scheuermann's is anterior (front) vertebral wedging of at least 5 degrees involving three consecutive vertebrae. The neck and head may present in an abnormal forward position. The onset usually begins (or is noticed) between the ages of 12 and 15 years affecting females more often than males. For many patients (up to 50%), pain is a common complaint.
