Recovery of motor deficit accompanying sciatica--subgroup analysis of a randomized controlled trial

In patients with sciatica due to a lumbar disc herniation, it is generally recommended to reserve surgical treatment for those who suffer from intolerable pain or those who demonstrate persistent symptoms after conservative management. Controversy exists about the necessity of early surgical intervention for those patients that have an additional motor deficit.

The aim of this study was to compare the recovery of motor deficit among patients receiving early surgery to those receiving prolonged conservative treatment.

Subgroup analysis of a randomized controlled trial.

This subgroup analysis focuses on 150 (53%) of 283 patients with sciatica due to a lumbar disc herniation and whose symptoms at baseline (before randomization) were accompanied by a motor deficit.

Motor deficit was assessed through manual muscle testing and graded according to the Medical Research Council (MRC) scale.

In total, 150 patients with 6 to 12 weeks of sciatica due to a lumbar disc herniation and whose symptoms were accompanied by a moderate (MRC Grade 4) or severe (MRC Grade 3) motor deficit were randomly allocated to early surgery or prolonged conservative treatment. Repeated standardized neurologic examinations were performed at baseline and at 8, 26, and 52 weeks after randomization. This study was supported by a grant from the Netherlands Organization for Health Research and Development (ZonMW) and the Hoelen Foundation The Hague.

Sciatica recovered among seven (10%) of the 70 patients assigned to early surgery before surgery could be performed, and of the 80 patients assigned to conservative treatment, 32 patients (40%) were treated surgically because of intolerable pain. Baseline severity of motor deficit was graded moderate in 84% of patients and severe in 16% of patients. Motor deficit recovered significantly faster among patients allocated to early surgery (p=.01), but the difference was no longer significant at 26 (p=.21) or 52 weeks (p=.92). At 1 year, complete recovery of motor deficit was found in 81% of patients allocated to early surgery and in 80% of patients allocated to prolonged conservative treatment. Perceived overall recovery of sciatica was directly related to the presence of an accompanying motor deficit. Severe motor deficit at baseline (odds ratio, 5.4; confidence interval, 1.7-17.4) and a lumbar disc herniation encompassing ≥25% of the cross-sectional area of the spinal canal (odds ratio, 6.4; confidence interval, 1.3-31.8) were the most important risk factors for persistent deficit at 1 year.

Early surgery resulted in a faster recovery of motor deficit accompanying sciatica compared with prolonged conservative treatment but the difference was no longer significant during the final follow-up examination at 1 year.