[Course of conservatively treated acute lumbar root compression syndrome. A computer tomography controlled study].

Of 129 patients with an acute lumbar root compression syndrome due to disc herniation 21, who were symptom-free, were examined by computed tomography (CT) on average 276 days after a three-step regimen of conservative treatment. In no instance had there been a deterioration of the original findings. In 14 patients the CT picture continued to demonstrate disc herniation, although the patients were without symptoms. In two patients a moderate, in five a marked regression of herniation was demonstrated by CT. Clinical improvement without change in the CT picture points to the compression syndrome not being explainable solely in mechanical terms. As a matter of fact, a possible cause may be a disturbance of radicular blood supply resulting in oedematous root swelling which is usually masked in the CT by prolapsed disc tissue. There is as yet no easy explanation for regression in case of prolapsed, perhaps even sequestered, disc tissue. It is possible that there have been reparative processes, such as have been described histopathologically in form of ingrown vessels. More plausibly would be a separation of the herniated and/or sequestered disc tissue in form of an asymptomatic sliding into the terminal caudal region.