Predictive Factors for Outcomes Following Surgical Treatment of Lumbar Disc Herniation

Int J Spine Surg. 2024 Sep 20:8650. doi: 10.14444/8650. Online ahead of print.

Abstract

Background: Lumbar disc herniation (LDH) is a common cause of radicular pain with an annual incidence between 5 and 20 cases per 1000 adults. LDH is typically treated by microdiscectomy, of which more than 300,000 are performed in the United States each year. Despite this frequency, 25% to 33% of patients report poor surgical outcomes. This study sought to present a retrospective analysis of patients who underwent microdiscectomy surgery for the treatment of LDH with the aim of identifying demographic, historical, and surgical factors that may contribute to inadequate surgical results.

Methods: A retrospective study of 241 patients at Stony Brook Medicine from 2017 to 2022 was performed, 123 of whom had follow-up of 90 days or more and were included for final analysis. Data collection included demographics, medical/surgical history, and surgical methodology. Good outcomes were defined as meeting the absolute point change threshold (ACT)-3.5pt reduction in pain reported by the Numerical Rating System (NRS) or the resolution of either radicular pain or neurological symptoms.

Results: Univariate analysis revealed that 100% of patients with prior fusion surgery (P = 0.039) and 73.2% who underwent preoperative physical therapy (PT; P = 0.032) failed to meet the ACT. Additionally, 79.1% (P = 0.021) and 82.8% (P = 0.026) of patients who had PT had residual radicular pain and neurological symptoms, respectively. Multivariate logistic regression confirmed correlations between preoperative PT and failure to meet the ACT (P = 0.030, OR = 0.252) and resolution of radicular (P = 0.006, OR = 0.196) and neurological (P = 0.030, OR = 0.177) complaints. ACT directly correlated with higher preoperative NRS scores in univariate (P = 0.0002) and multivariate (P = 0.002, OR = 1.554) analyses.

Conclusion: Our results show that higher preoperative NRS scores, PT, and prior fusion surgery are associated with poorer outcomes. While PT is considered a viable nonoperative treatment for LDH, our findings suggest detrimental effects when preceding surgery, indicating the need for additional research into the effects of PT on patients with high grade LDH.

Keywords: fusion; lumbar disc herniation; outcomes; physical therapy; retrospective; spine.