Comparison of the short-term efficacy of percutaneous endoscopic transforaminal lumbar interbody fusion with the application of a expandable versus PEEK cage for the treatment of lumbar degenerative disease.

OBJECTIVE: This study aimed to compare the short-term clinical efficacy of percutaneous endoscopic transforaminal lumbar interbody fusion (PE-TLIF) using expandable cages versus conventional static polyetheretherketone (PEEK) cages in the treatment of lumbar degenerative disease (LDD).

METHODS: A total of 67 patients diagnosed with lumbar degenerative disease who underwent PE-TLIF treatment at Xuzhou Central Hospital between February 2020 and December 2023 were enrolled for retrospective analysis. All patients were stratified into two groups based on the type of interbody fusion cage implanted: the expandable cage group (n = 31) and the conventional static PEEK cage group (n = 36). In the expandable group, the cohort consisted of 17 males and 14 females with a mean age of 62.48 ± 7.33 years, while the static group included 14 males and 22 females with a mean age of 60.89 ± 7.56 years. Perioperative indicators including operation duration, intraoperative blood loss, postoperative drainage volume, and postoperative hospital stay were systematically documented and compared between the two groups, and surgical complications were continuously monitored and recorded. For clinical functional assessment, the visual analog scale (VAS) for low back and leg pain and the Oswestry Disability Index (ODI) were evaluated preoperatively, as well as at 1 day, 1 month, 6 months, and 1 year postoperatively. Radiological parameters, including intervertebral disc height (IDH), intervertebral foraminal height (IFH), segmental surgical lordosis (SSL), and lumbar lordosis (LL), were measured before surgery and at the 1-year postoperative follow-up. The Bridwell fusion grading system was adopted to assess the status of intervertebral fusion at the final follow-up, and the modified MacNab criteria were utilized to comprehensively evaluate the overall clinical therapeutic efficacy.

RESULTS: There were no statistically significant differences in the general information of gender, age, surgical segment, and BMI between the expandable group and the static group (all P>0.05). The differences between the two groups were not statistically significant in terms of operative time, intraoperative hemorrhage, postoperative drainage and postoperative hospitalization time (all P>0.05). The low back pain VAS scores of both groups improved at all follow-up time points after operation compared to the preoperative period, and the low back pain VAS scores were lower in the expandable group than in the static group at 1 day and 1 month after operation, and the differences between the two groups were not statistically significant when comparing the other time points. The VAS scores of lower limb pain in both groups at each postoperative follow-up time points were improved compared with the preoperative period in both groups (P<0.0001) and the differences in lower limb pain VAS scores between the two groups at all postoperative time points were not statistically significant (all P > 0.05). The ODI index improved at each postoperative follow-up time point compared with the preoperative period in both groups, and there were no statistically significant differences in the ODI index between groups at each postoperative time point in both groups. There were no statistically significant differences in preoperative intervertebral disc height (IDH), intervertebral foraminal height (IFH), surgical segmental lordosis (SSL), and lumbar lordosis (LL) between the two groups of patients. Postoperative imaging indexes of both groups were significantly improved compared preoperative (all P<0.0001) and the expandable fusion device was better than the static group in improving the IDH, IFH, SSL (all P<0.0001), and the difference of the LL between the two groups after the operation was statistically not significant (P>0.05). A case of nerve root paralysis occurred after operation in the expandable group, a case of subarachnoid hemorrhage and a case of dural sac tear in the static group, and the difference in the complication rate between the two groups was not statistically significant [3.02% (1/31) vs. 5.56% (2/36)] (P > 0.05). The difference in intervertebral fusion rate between the two groups was not statistically significant according to Bridwell grading at the final follow-up [93.5% (29/31) vs. 91.67% (33/36)] (P > 0.05). According to the modified MacNab criteria, 27 cases were excellent, 3 cases were good, and 1 case was fair in the expandable group; 32 cases were excellent, 2 cases were good, and 2 cases were fair in the static group, and the difference was not statistically significant between the two groups (96.77% vs. 94.44% (34/36) (P > 0.05).

CONCLUSION: Both expandable and conventional static PEEK cages applied in percutaneous endoscopic transforaminal lumbar interbody fusion (PE-TLIF) yield satisfactory short-term clinical outcomes for lumbar degenerative diseases. Notably, the expandable cage demonstrates distinct superiority in restoring for optimizing lumbar lordosis and sagittal sequences.