Hyper-kyphosis [forward bend of the thoracic (ribbed) vertebrae beyond normal limits] is classified as either postural or structural in origin. Postural kyphosis will correct when the patient is asked to stand up straight. Patients with postural kyphosis have no abnormalities in the shape of the vertebrae. Scheuremann’s kyphosis is defined as rigid (structural) kyphosis because the front sections of the vertebrae grow slower than the back sections. This results in wedge-shaped vertebrae rather than rectangular shaped vertebrae that line up well (Figure 1 and 2). This process occurs during a period of rapid bone growth, usually between the ages of 12 and 15 years of age in males, or a few years earlier in females. The abnormal kyphosis is best viewed from the side in the forward-bending position where a sharp, angular abnormal kyphosis is clearly visible.
Figure 1: The right image shows a close-up of the wedged vertebrae inScheuremann’s
Patients with Scheuermann’s disease often present with poor posture and complaints of back pain. Back pain is most common during the early teenage years and in most instances will decrease as they approach adulthood. The pain rarely interferes with daily activity or professional careers. The kyphosis is more likely to be symptomatic if the apex (most angular section) is in the mid-to-low back instead of upper back. In severe cases, adolescents may not be able to lie on their back without several pillows under their head. The kyphotic deformity that develops with growth frequently remains mild and requires only periodic X-rays.
- A) Lateral x-ray of a patient with Scheuremann’s disease.
- B) Close-up x-ray demonstrating wedge-shaped vertebrae
characteristic of Scheuremann’s disease.
Observation is typically recommended in the following situations:
- Postural hyperkyphosis (their round back straightens with proper posture),
- Curves that are less than 60° in patients that are growing, or
- Curves 60°-80° in patients that are done growing.
Standing, long-cassette (scoliosis) X-rays are taken every 6 months as the child grows. If the child has pain, an exercise program is usually recommended.
Figure 1. On the left is a side-view of a patient with
Scheuremann’s kyphosis. On the right is the same X-ray
after he was placed in a hyperextension brace.
Bracing When the deformity is moderately severe (60°-80°) and the patient remains skeletally immature, brace treatment in conjunction with an exercise program is the recommended treatment. Full time use of a brace (20 hours/day) is usually required initially until maximum correction has been achieved. The brace fit must be regularly evaluated and adjusted to ensure optimal correction. During the last year of treatment prior to skeletal maturity, part time brace wear (12-14 hours/day) may be proposed. Brace wear must be continued for a minimum of 18 months in order to maintain a significant, permanent correction of the deformity (Figure 1).
When the kyphotic deformity has become severe (greater than 80o) and the patient is often experiencing increased back pain, surgical treatment may be recommended. Surgical intervention allows significant correction to be achieved typically without the need for postoperative bracing. Pedicle screws are placed (2 per level) and connected with two rods. This process allows gentle straightening of the spine. Most surgeries are performed from the back. However, some physicians recommend additional surgery on the front of the spine. Patients are usually able to return to normal daily activities within 4-6 months following surgery. The correction achieved from surgical intervention is remarkable (Figure 1).
Smith-Peterson (Posterior) Osteotomy Moderately flexible curves often straighten just from lying prone (face down) on the operating room table. However, rigid curves require additional steps. The Smith-Peterson osteotomy is often performed at multiple levels to allow safe application of additional corrective forces. Every spinal segment is limited in extension (backward bend) by two sliding facet joints. If these joints are removed, and the disc in front is mobile, approximately 5-10°/level of additional extension is possible to obtain (Figure 2)