Minimally Invasive Transforaminal Lumbar Interbody Fusion Ameliorates Persistent Pain After Lumbar Fusion Surgery

Background: Approximately 4-20% patients with degenerative lumbar diseases showed persistent pain after lumbar fusion surgery that may develop into failed back surgery syndrome (FBSS), and this persistent pain may be related to the postoperative increased release of inflammatory mediators. Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) can obviously reduce the intraoperative soft tissue trauma. The aim of this study is to investigate the persistent pain in the patients with degenerative lumbar diseases undergoing MIS-TLIF compared with conventional‑invasive TLIF. Material and methods: This study retrospectively included 146 patients (MIS-TLIF vs. conventional‑invasive TLIF: 56 vs. 90), and the incidence of persistent pain were evaluated. Furthermore, inflammation related markers in both blood and drainage fluid samples, including white blood cell (WBC) count, C-reactive protein (CRP), creatine kinase (CK), interleukin-6 (IL-6) and IL-1β, were tested before and after operation. Results: Significantly larger number of patients undergoing conventional‑invasive TLIF showed postoperative persistent pain compared to those undergoing MIS-TLIF (4/56, 7.1% vs. 20/90, 22.2%; P < 0.05). In both treatment groups, the patients with postoperative persistent pain showed increased IL-6 and IL-1β in drainage fluid, as well as increased IL-6 in blood samples (P < 0.05), and there is significant correlation between the inflammation markers in drainage fluid and the extent of postoperative persistent pain in patients with postoperative persistent pain (P < 0.05). Conclusions: Local inflammatory substance accumulation may be potential cause for postoperative persistent pain, and MIS-TLIF may reduce this inflammatory accumulation at the surgical site and subsequently reduce the risk of persistent pain.