Foraminoplasty affects the clinical outcomes of discectomy during percutaneous transforaminal endoscopy: a two-year follow-up retrospective study on 64 patients.

The aim of this study was to assess the significance of how the degree of injury of the facet joint affects clinical outcomes in foraminoplasty. We retrospectively enrolled 64 patients treated with percutaneous endoscopic transforaminal discectomy with foraminoplasty (PETDF) from January of 2015 to December of 2016. The patients were divided into two groups depending on whether the articular surface of the facet joint was damaged. Preoperative, perioperative, demographic data, and radiographic parameters for these two groups were extracted and compared. There were no significant differences between the two groups in terms of the duration of operation (P = 0.331), intraoperative blood loss volume (P = 0.631), the weight of disc (P = 0.274) or cut bone (P = 0.526). There were no significant differences between the two groups for VAS or ODI at the same time point (P > 0.05). There were significant differences in the VAS scores of low-back pain at 24 hours and 24 months after surgery in the injured group. There were significant differences in ISH, ISA, rate of lumbar instability, recurrent herniation, and Macnab scores between the two groups at 24 months after surgery (P < 0.05). The regression equation between ISA and ISH was Y = 4.237 + 0.565x (where Y denotes an increase of ISA; X, reduction of ISH; F = 6.219, P = 0.015). The Poisson ratio was 0.363 (P = 0.003). PETDF is effective and safe for the treatment of lumbar disc herniation. However, when foraminoplasty destroys the articular surface of the facet joint, there may be increases in lumbar instability and recurrence rate post-operation.