What Causes Pain and Disability in Adults with Severe Scheuermann's Kyphosis?

Introduction: Adults with severe Scheuermann's disease (deformity > 65 degrees) may, but not always, have pain and disability. It has been suggested that disability may be associated with the magnitude or location of the deformity, as well as with endplate changes and Schmorl's nodes. This study was performed to determine which aspects of adult Scheuermann's disease are associated with pain and disability.

Materials and Methods: Twenty-four adult patients with symptomatic Scheuermann's disease and a kyphotic deformity measuring greater than 65 degrees were retrospectively studied. Standing PA and lateral radiographs were taken in all patients. Hyperextension views were also taken. Measurements including apex of deformity, magnitude of deformity, kyphosis at thoracolumbar junction (T11-L1), number of levels with Schmorl's nodes, and flexible correction with hyperextension films were measured. In addition, Oswestry functional scores were generated from chart review. Linear regression analysis was used to compare radiographic measures with Oswestry scores. T-test was used to compare mean Oswestry scores between patient with apex at or above T9 and patients with an apex below T9.

Results: No statistically significant association was found between the magnitude of deformity, number of levels with Schmorl's nodes, or amount of flexible correction on hyperextension films (p>0.05). A statistically significant postive association was found between kyphosis at the thoracolumbar junction and Oswestry score (p=0.03). In addition, patients with an apex below T9 had a significantly higher mean Oswestry scores than did patients with apex at T9 or above (p=0.03).

Conclusion: Pain and disability in adults with severe Scheuermann's disease is associated with amount of thoracolumbar kyphosis and apex of deformity below T9. The absolute magnitude or flexibility of the deformity, and the number of Schmorl's nodes are not associated with amount of pain and disability.