We analysed prospectively 26 patients who had revision operations for ipsilateral recurrent radicular pain after a period of pain relief of more than six months following primary discectomy. They were assessed before the initial operation, between the two procedures and at a minimum of two years after reoperation. MRI was performed before primary discectomy and reoperation. Fifty consecutive patients who had a disc excision during the study period but did not have recurrent radicular pain, were analysed as a control group.

Of the study group 42% related the onset of recurrent radicular pain to an isolated injury or a precipitating event, but none of the control group did so (p < 0.001). T2-weighted MRI performed before primary discectomy showed that patients in the study group had significantly more severe disc degeneration compared with the control group (p = 0.02). Intraoperative findings revealed recurrent disc herniation in 24 patients and bulging of the disc in two, one of whom also had lateral stenosis. Epidural scarring was found to be abundant, intraoperatively and on MRI, in eight and in nine patients, respectively.

At the last follow-up, the clinical outcome was satisfactory in 85% of patients in the study group and in 88% of the control group (p > 0.05). Work or daily activities had been resumed at the same level as before the onset of symptoms by 81% of the patients in the study group and 84% of the control group. No correlation was found between the amount of epidural fibrosis, as seen intraoperatively and on MRI, and the result of surgery. The recurrence of radicular pain caused no significant changes in the psychological profile compared with the assessment before the primary discectomy.