Sciatica-Related Spinal Imbalance in Lumbar Disc Herniation Patients: Radiological Characteristics and Recovery Following Endoscopic Discectomy

BACKGROUND: Sciatica-related spinal imbalance could be observed in lumbar disc herniation (LDH) patients. However, their characteristics and recovery process remained unclear. The purpose was to analyze the radiological characteristics of spinal imbalance related to sciatica and recovery following endoscopic discectomy. METHODS: The records of LDH patients with sciatica and spinal imbalance receiving endoscopic discectomy were retrospectively reviewed. The patients were divided to Group A (sagittal imbalance), Group B (coronal imbalance) and Group C (sagittal and coronal imbalance). The whole-spine x-ray was performed at pre-operation, immediately post-operation, 3-month and 6-month follow-up and related radiological parameters were measured. RESULTS: A total of 110 LDH patients (18.3%) presented with spinal imbalance were included and there were 31 patients in Group A, 38 patients in Group B and 41 patients in Group C. In this study, 77.2% of the coronal imbalance patients present with trunk shifted to contralateral side of disc herniation and 65.3% of the sagittal imbalance patients present with forward trunk. Most patients present mild and moderate sagittal and coronal imbalance. The magnitude of sagittal and coronal imbalance in Group C was significantly more severe than that of Group A and Group B. Most patients (≥75%) acquired spinal balance immediately after surgery. The sagittal imbalance improved better than coronal imbalance and single plane imbalance improved better than biplane imbalance. At the postoperative 6-month follow-up, all patients recovered to normal sagittal and coronal balance. CONCLUSION: Sciatica-related spinal imbalance occurs in 18.3% of the LDH patients receiving endoscopic discectomy. Different subgroups of spinal imbalance present different characteristics. Spontaneous correction of the spinal imbalance could be achieved when sciatica was relieved immediately after surgery and well maintained during follow-up.