Objective:

The purpose of this study was to analyze whether the type of preoperative pain affects the improvement in postoperative pain intensity in patients with a lumbar degenerative disease (LDD).

Methods:

We retrospectively reviewed 93 patients who underwent lateral lumbar interbody fusion (LLIF) without direct decompression. All patients were evaluated using Numeric Rating Scale (NRS) scores for low back pain (NRS_LBP), leg pain (NRS_LP), and leg numbness (NRS_LN) and imaging data before and after LLIF surgery. Based on the Japanese version of the painDETECT (PDQ-J) scores, patients were classified into three groups: a neuropathic pain (NeP) group, a nociceptive pain (NocP) group, and an intermediate mixed pain (MixP) group.

Results:

The PDQ-J identified NeP in 20.4% of patients with LDD prior to LLIF. Preoperative NRS_LBP, NRS_LP, and NRS_LN scores were higher in the NeP group than in the NocP group. All types of pain improved after LLIF surgery. The NRS_LBP score 12 months after surgery was higher in the NeP group (3.8 ± 2.8) than in the NocP group (1.9 ± 2.2) (p = 0.008). Similar results were obtained with NRS_LP (NeP group 3.1 ± 2.8, NocP group 1.5 ± 2.0, p = 0.010).

Conclusions:

Although LLIF was useful for relieving all types of preoperative pain in LDD patients, the NRS scores for preoperative pain were higher in the NeP group than in the NocP group, and the postoperative NRS_LBP and NRS_LP score was significantly higher in the NeP group. Thus, controlling preoperative NeP may improve therapeutic efficacy.