Scheuermann's Kyphosis

Overview

Kyphosis is used to describe the condition of increased forward spinal angulation in the sagittal plane (looking at someone from the side).

Scheuermann's kyphosis is condition in which the spine bones (vertebrae) are wedged-shaped at three or more levels in the spine. The strict medical definition is anterior wedging of 5 degrees at three or more vertebral in the spine. This is most often seen in the thoracic spine region, causing a kyphotic "roundback" deformity or the patient to appear hunched over rather than standing up straight and tall. Scheuermann's disease is often diagnoses during adolescence, and rarely is identified in patients younger than 10 years-old. There is also a 20-30% incidence of associated scoliosis, so this must be checked for as well.

Causes

The etiology, or cause, or Scheuermann's disease is idiopathic. Idiopathic is a medical term meaning that the cause is unknown, and it occurs it an otherwise totally normal, healthy child. There are theories that the condition is due to mechanical, metabolic, or endocrinologic problems, but this has yet to be proven. Similar to scoliosis, Scheuermann's disease is a hereditary condition, but it is multi-factorial so there is no clear inheritance pattern. There are two main types of Scheuermann's kyphosis, one with an apex at the mid-thoracic level (T7-T9) and one type with the apex located at the thoracolumbar junction (T11-T12).

Symptoms

Back pain is the most common presenting symptom, although many patients, and especially parents may notice the kyphotic spinal curvature if the roundback deformity. Patients may feel as if they are "off balance," or they cannot stand up straight which occurs because their head and torso is frequently shifted forward. Patients often have severe tightness of the hamstrings causing deficient lumbar range-of-motion and flexibility. Children rarely have leg pain (sciatica), or other symptoms such as numbness or weakness. If present, a magnetic resonance imaging (MRI) test should be obtained to evaluate the possibility of a neurologic lesion.

Physical Findings

The most prominent finding on physical examination is the spinal deformity, which manifests as a roundback deformity or "hunched over" appearance. There may be spinal tenderness and spasm. Patients with significant hamstring tightness will often have markedly decreased range-of-motion of the lumbar spine. The neurologic examination is usually always normal.

Imaging Studies

X-rays are the most important imaging study to obtain when evaluating kyphosis. Long plate, tri-fold anteroposterior (AP - x-ray is taken facing the patient directly) and lateral (x-ray is taken from the side view) x-rays should be taken with the patient standing in order to adequately evaluate a spinal deformity - both scoliosis and kyphosis. Irregularities of the vertebral endplates are hallmark finding send on lateral x-rays. Side-bending and backward bending (or extended supine) x-rays are also obtained to understand how flexible a spinal curvature is before surgery is undertaken. A magnetic resonance imaging (MRI) test may also be indicated if there are leg pain (sciatica) symptoms or neurologic dysfunction.

Laboratory Tests

There are no laboratory tests used to diagnose Scheuermann's kyphosis. Occasionally, specific tests are ordered to rule out infection or other medical/rheumatologic conditions.

Diagnosis

The diagnosis of Scheuermann's kyphosis may be suspected if a roundback deformity is present. However, an x-ray is required to confirm the diagnosis, as well as to evaluate the severity of the deformity and curvature.

Treatment

The treatment of Scheuermann's kyphosis depends on the severity of the pain and kyphotic deformity. Essentially all patients are recommended for conservative treatment initially unless there is such a severe deformity and pain on first presentation. Normal thoracic kyphosis is 20-45 degrees, which is expected to increase slightly with age. Patients with a kyphosis deformity of 50-70 degrees are generally recommended for brace treatment. A Milwaukee brace is the recommended brace to prescribe. Bracing for deformities greater than 75 degrees is frequently ineffective and at he discretion of the treating physician. Physical therapy and chiropractic care can often provide symptomatic relief of pain, but the overall efficacy is unproven. The natural history studies of Scheuermann's kyphosis report the majority of adolescents have improvement of back pain after skeletal maturity is reached and the deformity usually does not progress. Surgical indications include patients with greater than 75 degrees kyphosis or significant kyphosis (60 degrees) with pain unrelieved with conservative treatment. A posterior fusion with instrumentation is the procedure of choice. The results of surgery are very good, both for correction of curvature and improvement of pain.

Selected Bibliography

Lowe TG: Scheuermann's disease and postural round back. J Bone Joint Surg Am 1990;72:940.

Murray PM, Weinstein SL, Spratt K: Natural history and long term follow-up of Scheuermann's kyphosis. J Bone Joint Surg Am 1993;75:236.

Ponte A, Siccardi GL, Ligure P: Scheuermann's kyphosis: posterior shortening procedure by segmental closing wedge osteotomies. J Pediatr Orthop 1995;15:404.

Sachs B, Bradford D, Winter R, et al: Scheuermann's kyphosis: follow-up of Milwaukee brace treatment. J Bone Joint Surg Am 1987;69:50.