Abstract
Introduction: In recent years, circumferential minimally invasive surgery (CMIS) using lateral lumbar interbody fusion (LLIF) and percutaneous pedicle screws (PPS) has been used for adult spinal deformity (ASD). It has gradually become popular. However, no clear standards indicate the extent to which CMIS can be applied to spinal deformities. In this study, we investigated the conditions for satisfying postoperative PI-LL <10° in CMIS.
Methods: The subjects were 145 patients with ASD who had undergone CMIS at our hospital since 2018 and were followed up for more than 2 years. The fixation range was from the lower thoracic vertebrae to the pelvis in all the cases. The mean age was 72.1 years, and the mean follow-up period was 54 months. The patients were divided into two groups: G group with PI-LL < 10° and P group with PI-LL ≥10° in the postoperative standing lateral view of the entire spine. Patient background, various parameters, Oswestry Disability Index (ODI), and low back pain/leg pain visual analogue scale (VAS) were compared. Furthermore, we investigated the risk factors for postoperative PI-LL ≥10° using a multivariate logistic analysis.
Results: There were no significant differences between the two groups in terms of age, gender, follow-up period, diameter and number of rods used, number of fused levels, number of LLIF procedures, surgical time, and blood loss. Postoperative low back pain VAS and postoperative ODI were significantly higher in group P. Regarding various parameters, preoperative PI, postoperative LL, preoperative/post-LLIF/postoperative PI-LL were significantly greater in the P group, and preoperative PT was significantly greater. Multivariate analysis showed that post-LLIF PI-LL was a factor for postoperative PI-LL ≥10°, with a cutoff value of 20°.
Conclusions: Post-LLIF PI-LL was detected as a risk factor for postoperative PI-LL ≥10° in CMIS for ASD, with a cutoff value of 20°.
