Surgical treatment of thoracic spinal stenosis: a 2- to 9-year follow-up.

STUDY DESIGN

A retrospective investigation of the results of operative treatment of patients with symptomatic thoracic spinal stenosis.

OBJECTIVES

To establish the effectiveness and define the limitations of surgical treatment for stenosis of the thoracic spinal canal.

SUMMARY OF BACKGROUND DATA

In contrast to cervical and lumbar stenosis, symptomatic narrowing of the thoracic spinal canal is rarely encountered. Although the treatment of thoracic stenosis has been described in multiple case reports and in several small series with minimal follow-up evaluation, there are few studies of patients treated surgically for this condition with follow-up evaluation beyond 2 years.

METHODS

Twelve patients who underwent operative decompression for symptomatic stenosis of the lower thoracic spine were followed up for an average period of 62.4 months. Surgery was performed on the thoracic spine alone in four cases and on the combined thoracolumbar spine in eight. Factors that were investigated included pain severity, lower extremity motor function, ambulatory status, and postoperative complications.

RESULTS

The level of pain after surgery was decreased in eight patients and unchanged in four patients. Of the 10 patients with a motor deficit before surgery, eight had improvement of muscle function. Of the 11 patients with a gait disturbance before surgery, ambulatory status was improved in seven, unchanged in two, and worse in two. One patient lost neural function secondary to surgical intervention. There were five cases in which the early result subsequently deteriorated because of recurrent stenosis, spinal deformity/instability, or both.

CONCLUSIONS

Thoracic stenosis can occur in isolation or, more commonly, in association with lumbar stenosis. Ideally, operative treatment should address all stenotic segments and directly decompress the primary anatomic abnormalities causing neural element compression. Although satisfactory short-term results can be expected, deterioration of the early outcome because of the potential for recurrent stenosis and deformity/instability at the thoracolumbar junction can sometimes be seen with longer follow-up evaluation periods.