Characteristics of relief and residual low back pain after discectomy in patients with lumbar disc herniation: analysis using a detailed visual analog scale

BackgroundSeveral authors have reported favorable results in low back pain (LBP) for patients with lumbar disc herniation (LDH) treated with discectomy. However, detailed changes over time in the characteristics and location of LBP before and after discectomy for LDH remain unclear. To clarify these points, we conducted an observational study to determine the detailed characteristics and location of LBP before and after discectomy for LDH, using a detailed visual analog scale (VAS) bilaterally.MethodsWe included 65 patients with LDH treated by discectomy in this study. A detailed VAS for LBP was administered with the patient under 3 different conditions: in motion, standing, and sitting. Bilateral VAS was also administered (affected versus opposite side) for LBP, lower extremity pain (LEP), and lower extremity numbness (LEN). The Oswestry Disability Index (ODI) was used to quantify clinical status. Changes over time in these VAS and ODI were investigated. Pfirrmann grading and Modic change as seen by magnetic resonance imaging (MRI) were reviewed before and 1year after discectomy to determine disc and endplate condition.ResultsBefore surgery, LBP on the affected side while the patients were in motion was significantly higher than LBP while they were sitting (p=0.025). This increased LBP on the affected side in motion was improved significantly after discectomy (p<0.001). By contrast, the residual LBP while sitting at 1year after surgery was significantly higher than the LBP while they were in motion or standing (p=0.015). At 1year following discectomy, residual LBP while sitting was significantly greater in cases showing changes in Pfirrmann grade (p=0.002) or Modic type (p=0.025).ConclusionsImprovement of LBP on the affected side while the patient is in motion suggests that radicular LBP is improved following discectomy by nerve root decompression. Furthermore, residual LBP may reflect increased load and pressure on the disc and endplate in the sitting position.

Automated summary

Patients with lumbar disc herniation treated with discectomy may experience improvement in radicular low back pain while in motion, suggesting successful nerve root decompression. Residual low back pain while sitting post-surgery may indicate increased load and pressure on the disc and endplate.