Superior Facet Joint Violations in Single Level Minimally Invasive and Open Transforaminal Lumbar Interbody Fusion: A Comparative Study

Pedicle Screw-Associated Violation of the Adjacent Unfused Facet Joint: Clinical Outcomes and Fusion Rates

STUDY DESIGN

Retrospective review of a prospective randomized trial.

OBJECTIVES

To compare outcome scores and fusion rates in patients with and without pedicle screw-associated facet joint violation (FJV) after a single-level lumbar fusion.

METHODS

Clinical outcomes data and computed tomography (CT) imaging were reviewed for 157 patients participating in a multicenter prospective trial. Post-operative CT scans at 12-months follow-up were examined for fusion status and FJV. Patient-reported outcomes (PROs) included Oswestry Disability Index (ODI) and Visual Analog Scale (VAS) for leg and low back pain. Chi-square test of independence was used to compare proportions between groups on categorical measures. Two-sample t-test was used to identify differences in mean patient outcome scores. Logistic regression models were performed to determine association between FJV and fusion rates.

RESULTS

Of the 157 patients included, there were 18 (11.5%) with FJV (Group A) and 139 (88.5%) without FJV (Group B). Patients with FJV experienced less improvement in ODI (P = .004) and VAS back pain scores (P = .04) vs patients without FJV. There was no difference in mean VAS leg pain (P = .4997). The rate of fusion at 12-months for patients with FJV (27.8%) was lower compared to those without FJV (71.2%) (P = .0002). Patients with FJV were 76% less likely to have a successful fusion at 12-months.

CONCLUSION

Pedicle screw-associated violation of the adjacent unfused facet joint during single-level lumbar fusion is associated with less improvement in back pain, back pain-associated disability, and a lower fusion rate at 1-year after surgery.

Biomechanical evaluation of modified and traditional cortical bone trajectory technique on adjacent segment degeneration in transforaminal lumbar interbody fusion-finite element analysis

OBJECTIVES

Modified cortical bone trajectory (MCBT) technique was proposed by our team in previous studies, but its biomechanical properties at adjacent segments have not been discussed yet. Therefore, the purpose of this study is to investigate the biomechanical properties of modified cortical bone trajectory (MCBT) technique on adjacent segment degeneration (ASD) in transforaminal intradiscal lumbar disc fusion (TLIF) compare to traditional bone trajectory (TT) technique and cortical bone trajectory (CBT) technique.

METHODS

The four human cadaveric lumbar specimens were provided by the anatomy teaching and research department of Xinjiang Medical University and four intact finite element models of the L1-S1 segment were generated. For each of these, three transforaminal lumbar interbody fusion procedures with three different fixation techniques were reconstructed at the L4-L5 segment, as follows: TT-TT (TT at both L4 and L5 segments), CBT-CBT (CBT at both L4 and L5 segments), MCBT-MCBT (MCBT at both L4 and L5 segments). The range of motion and von Mises stress of the intervertebral disc of the L3-L4 and L5-S1 segments were recorded with a 400N compressive load and 7.5 Nm moments in flexion, extension, left-right bending, and left-right rotation.

RESULTS

The peak ROM of the L3-L4 segment in the MCBT-MCBT group was reduced by 10.5%, 6.1%, 12.2%, 4.1%, and 1.5% in flexion, extension, left-right bending, and left rotation compared to the TT-TT group and reduced by 1.8%, 5.5%, 10.0%, 12.8%, and 8.8% in flexion, left-right bending, and left-right rotation compared to the CBT-CBT group, respectively. The MCBT-MCBT group has the lowest peak ROM of the L3-L4 segment in flexion, left bending, and right rotation, the lowest peak ROM of the L5-S1 segment in extension and right rotation, and the lowest peak von Mises stress of the intervertebral disc at the L5-S1 segment in right rotation compared to the TT-TT and CBT-CBT group. In addition, the peak von Mises stress at the L3-L4 segment was lowest and more dispersed in all motions, the MCBT-MCBT group exhibited lower peak ROM of the L5-S1 segment in flexion, extension, and right rotation, and showed lower peak von Mises stress of the disc at the L5-S1 segment in flexion, extension, and right rotation compared with the TT-TT group.

CONCLUSION

The modified cortical bone trajectory technique may have a beneficial effect on reducing the incidence of ASD in the L4-L5 TLIF model compared to the traditional bone trajectory technique and cortical bone trajectory technique.

Endoscopic Lumbar Interbody Fusion, Minimally Invasive Transforaminal Lumbar Interbody Fusion, and Open Transforaminal Lumbar Interbody Fusion for the Treatment of Lumbar Degenerative Diseases: A Systematic Review and Network Meta-Analysis

STUDY DESIGN

network meta-analysis.

OBJECTIVE

To compare the clinical efficacy and safety of endoscopic lumbar interbody fusion (Endo-LIF), minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF), and open transforaminal lumbar interbody fusion (OTLIF) in the treatment of lumbar degenerative diseases (LDDs).

METHOD

A literature search was conducted in the PubMed, Embase, and Cochrane Library databases. Studies comparing Endo-LIF, MIS-TLIF and OTLIF published from September 2017 to September 2022 for the treatment of LDD were retrieved. Data were extracted from preset clinical outcome measures, including operation time, estimated intraoperative estimated blood loss (EBL), length of hospital stay (LOS), complications, visual analog scale (VAS) score, Oswestry disability index (ODI) score, etc.

RESULT

Thirty-one studies with 3467 patients were included in this study. Network meta-analysis showed that in the comparison of the 3 procedures, Endo-LIF was superior to MIS-TLIF and OTLIF in terms of reducing EBL, LOS, time to ambulation, and VAS score of back pain. MIS-TLIF was superior to Endo-LIF in terms of ODI improvement, and OTLIF required the shortest intraoperative fluoroscopy time. There was no significant difference in operative time, complication rate, fusion rate, VAS score of leg pain, or JOA score among the 3 procedures.

CONCLUSION

Endo-LIF, MIS-TLIF and OTLIF each have their own advantages and disadvantages and show similar results in many respects, except for better early outcomes achieved with the more minimally invasive procedure.

Superior facet joint violation between open and minimally invasive techniques in lumbar fusion surgery: An updated systematic review and meta-analysis

BACKGROUND

Superior facet joint violation (FJV) is a potential risk factor for adjacent segment disease following lumbar fusion surgery. We sought to conduct a systematic review and meta-analysis to compare screw-related superior FJV rates between the open and different minimally invasive (MI) techniques-fluoroscopy-based, 3D-image navigation, and navigation with robotic assistance-in adult lumbar fusion surgery.

METHODS

We searched original articles comparing the rates of screw-related FJV between the open and different MI techniques in adult lumbar fusion surgery for lumbar degenerative diseases in PubMed, EMBASE, and the Cochrane Library from inception to September 2021. We compared the numbers of top-level pedicle screws and associated superior FJVs in the main analyses and performed subgroup analysis based on different MI techniques to examine whether individual MI approaches differed in superior FJV rate. Risk ratio (RR) and 95% confidence interval (CI) were calculated in a random-effect meta-analysis.

RESULTS

Included in the meta-analysis were 16 articles with 2655 patients and 4638 top-level pedicle screws. The pooled analysis showed no significant difference in superior FJV rates between the MI and open groups (RR: 0.89, 95% CI: 0.62-1.28). The subgroup analysis demonstrated that the overall rates of superior FJV were 27.1% (411/1518) for fluoroscopy-based, 7.1% (43/603) for 3D-image navigation, and 3.2% (7/216) for navigation with robotic assistance. Compared with the open method, the overall RRs were 1.53 (95% CI: 1.19-1.96) for fluoroscopy-based, 0.41 (95% CI: 0.22-0.75) for 3D-image navigation, and 0.25 (95% CI: 0.08-0.72) for navigation with robotic assistance.

CONCLUSION

Among the three common MI techniques, fluoroscopy-based can be associated with a higher risk of superior FJV, while both 3D-image navigation and navigation with robotic assistance may be associated with lower risks as compared with the open method. Considering the limitations of the study, more trials are needed to prove these clinical findings.

Predictors of accurate intrapedicular screw placement in single-level lumbar (L4-5) fusion: robot-assisted pedicle screw, traditional pedicle screw, and cortical bone trajectory screw insertion

Background

The superiorities in proximal facet joint protection of robot-assisted (RA) pedicle screw placement and screw implantation via the cortical bone trajectory (CBT) have rarely been compared. Moreover, findings on the screw accuracy of both techniques are inconsistent. Therefore, we analyzed the screw accuracy and incidence of facet joint violation (FJV) of RA and CBT screw insertion in the same study and compared them with those of conventional pedicle screw (PS) insertion. The possible factors affecting screw accuracy and FJV were also analyzed.

Methods

A total of 166 patients with lumbar degenerative diseases requiring posterior L4-5 fusion were retrospectively included and divided into the RA, PS, and CBT groups from March 2019 to December 2021. The grades of intrapedicular accuracy and superior FJV were evaluated according to the Gertzbin–Robbins scale and the Babu scale based on postoperative CT. Univariable and multivariable analyses were conducted to assess the possible risk factors associated with intrapedicular accuracy and superior FJV.

Results

The rates of optimal screw insertion in the RA, PS, and CBT groups were 87.3%, 81.3%, and 76.5%, respectively. The difference between the RA and CBT groups was statistically significant (P = 0.004). Superior FJVs occurred in 28.2% of screws in RA, 45.0% in PS, and 21.6% in CBT. The RA and CBT groups had fewer superior FJVs than the PS group (P = 0.008 and P < 0.001, respectively), and no significant difference was observed between the RA and CBT groups (P = 0.267). Multivariable analysis revealed that the CBT technique was an independent risk factor for intrapedicular accuracy. Furthermore, older age, the conventional PS technique and a smaller facet angle were independently associated with the incidence of superior FJVs.

Conclusions

The RA and CBT techniques were associated with fewer proximal FJVs than the PS technique. The RA technique showed a higher rate of intrapedicular accuracy than the CBT technique. The CBT technique was independently associated with screw inaccuracy. Older age, conventional PS technique and coronal orientation of the facet join were independent risk factors for superior FJV.

Recent Updates on Minimally Invasive Spine Surgery: Techniques, Technologies, and Indications

A number of minimally invasive spine surgeries (MISSs) have been developed to address the drawbacks of open spine surgery. Their advantages include small skin incisions, reduction in tissue damage, quick recovery, and short hospital stay. However, the clinical outcomes are comparable to open surgery. There was a cap on the number of indications that could be set for all spinal illnesses. The indications for MISSs have been expanding owing to mechanical and technological advances in medical equipment. Thus, this review presents the various MISSs developed to date, surgical indications, surgical techniques, and their advantages and disadvantages.

Influence of the facet joint angle on facet joint degeneration following pedicle screw fixation without fusion in thoracolumbar fractures

BACKGROUND

Posterior approach pedicle screw fixation without fusion is widely used in the treatment of neurologically intact type A3 thoracolumbar fractures.

OBJECTIVE

To analyze the influence of the facet joint (FJ) angle on FJ degeneration following posterior approach pedicle screw fixation without fusion in neurologically intact type A3 thoracolumbar fractures.

METHODS

Fifty-eight patients who underwent pedicle screw fixation via the traditional posterior approach (n= 28) or the Wiltse approach (n= 30) were enrolled. A CT scan was performed before fixation and before fixation removal (Within 1.5 to 2 years after fixation) to evaluate the FJs parameters, including FJ inclination (FJI), FJ tropism (FJT), FJ violation, and FJ degeneration grade (FJDG), of three fixed segments and the adjacent segment below the fixed segments.

RESULTS

There was no significant difference in FJ violation rate, FJDG deterioration, or FJ angle between the two groups (P> 0.05). FJDG deterioration showed a weak positive correlation with FJI and FJT before fixation, and the angular change in FJI (P< 0.05); and FJT before fixation and the angular change in FJI were risk factors for FJDG deterioration (P< 0.01).

CONCLUSION

The Wiltse approach did not increase the rate of FJDG deterioration and FJs angle changes. However, the FJT before fixation and the angular change in FJI were risk factors for FJDG deterioration.

Safety and risk factors of TINAVI robot-assisted percutaneous pedicle screw placement in spinal surgery

Objective

To determine the rates and risk factors of pedicle screw placement accuracy and the proximal facet joint violation (FJV) using TINAVI robot-assisted technique.

Methods

Patients with thoracolumbar fractures or degenerative diseases were retrospectively recruited from June 2018 and June 2020. The pedicle penetration and proximal FJV were compared in different instrumental levels to identify the safe and risk segments during insertion. Moreover, the factors were also assessed using univariate and multivariate analyses.

Results

A total of 72 patients with 332 pedicle screws were included in the current study. The optimal and clinically acceptable screw positions were 85.8% and 93.4%. Of the 332 screws concerning the intra-pedicular accuracy, 285 screws (85.8%) were evaluated as Grade A according to the Gertzbein and Robbins scale, with the remaining 25 (7.6%), 10 (3.0%), 6 (1.8%), and 6 screws (1.8%) as Grades B, C, D, and E. Moreover, in terms of the proximal FJV, 255 screws (76.8%) screws were assessed as Grade 0 according to the Babu scale, with the remaining 34 (10.3%), 22 (6.6%), and 21 screws (6.3%) as Grades 1, 2, and 3. Furthermore, the univariate analysis showed significantly higher rate of penetration for patients with age < 61 years old, sex of female, thoracolumbar insertion, shorter distance from skin to insertion point, and smaller facet angle. Meanwhile, the patients with the sex of female, BMI < 25.9, grade I spondylolisthesis, lumbosacral insertion, longer distance from skin to insertion point, and larger facet angle had a significantly higher rate of proximal FJV. The outcomes of multivariate analyses showed that sex of male (adjusted OR 0.320, 95% CI 0.140–0.732; p = 0.007), facet angle ≥ 45° (adjusted OR 0.266, 95% CI 0.090–0.786; p = 0.017), distance from skin to insertion point ≥ 4.5 cm (adjusted OR 0.342, 95% CI 0.134–0.868; p = 0.024), and lumbosacral instrumentation (adjusted OR 0.227, 95% CI 0.091–0.566; p = 0.001) were independently associated with intra-pedicular accuracy; the L5 insertion (adjusted OR 2.020, 95% CI 1.084–3.766; p = 0.027) and facet angle ≥ 45° (adjusted OR 1.839, 95% CI 1.026–3.298; p = 0.041) were independently associated with the proximal FJV.

Conclusion

TINAVI robot-assisted technique was associated with a high rate of pedicle screw placement and a low rate of proximal FJV. This new technique showed a safe and precise performance for pedicle screw placement in spinal surgery. Facet angle ≥ 45° is independently associated with both the intra-pedicular accuracy and proximal FJV.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-022-03271-6.

Rates and risk factors of intrapedicular accuracy and cranial facet joint violation among robot-assisted, fluoroscopy-guided percutaneous, and freehand techniques in pedicle screw fixation of thoracolumbar fractures: a comparative cohort study

Background

Robot-assisted (RA) technique has been increasingly applied in clinical practice, providing promising outcomes of inserting accuracy and cranial facet joint protection. However, studies comparing this novel method with other assisted methods are rare, and the controversy of the superiority between the insertion techniques remains. Thus, we compare the rates and risk factors of intrapedicular accuracy and cranial facet joint violation (FJV) of RA, fluoroscopy-guided percutaneous (FP), and freehand (FH) techniques in the treatment of thoracolumbar fractures.

Methods

A total of 74 patients with thoracolumbar fractures requiring pedicle screw instruments were retrospectively included and divided into RA, FP, and FH groups from June 2016 to May 2020. The primary outcomes were the intrapedicular accuracy and cranial FJV. The factors that affected the intrapedicular accuracy and cranial FJV were assessed using multivariate analyses.

Results

The optimal intrapedicular accuracy of pedicle screw placement (Grade A) in the RA, FP, and FH groups was 94.3%, 78.2%, and 88.7%, respectively. This finding indicates no significant differences of RA over FH technique (P = 0.062) and FP technique (P = 0.025), but significantly higher accuracies of RA over FP (P < 0.001). In addition, the rates of proximal FJV in RA, FP, and FH groups were 13.9%, 30.8%, and 22.7%, respectively. RA had a significantly greater proportion of intact facet joints than the FP (P = 0.002). However, FP and FH (P = 0.157), as well as RA and FH (P = 0.035) showed significantly similar outcomes with respect to the proximal FJV. The logistic regression analysis showed that FP technique (OR = 3.056) was independently associated with insertion accuracy. Meanwhile, the age (OR = 0.974), pedicle angle (OR = 0.921), moderate facet joint osteoarthritis (OR = 5.584), and severe facet joint osteoarthritis (OR = 11.956) were independently associated with cranial FJV.

Conclusion

RA technique showed a higher rate of intrapedicular accuracy and a lower rate of cranial FJV than FP technique, and similar outcomes to FH technique in terms of intrapedicular accuracy and cranial FJV. RA technique might be a safe method for pedicle screw placement in thoracolumbar surgery.

Level of evidence

3

Multivariate analysis of pedicle screw invasion of the proximal facet joint after lumbar surgery

BACKGROUND

To analyze the risk factors for pedicle screw invasion of the proximal facet joint after lumbar surgery.

METHODS

From January 2019 to January 2021, 1794 patients with lumbar degenerative disease, such as lumbar disc herniation, lumbar spinal stenosis and lumbar spondylolisthesis, were treated at our hospital. In all, 1221 cases were included. General data (sex, age, BMI), bone mineral density, proximal facet joint angle, degenerative lumbar spondylolisthesis, isthmic lumbar spondylolisthesis and fixed segment in the two groups were recorded. After the operation, vertebral CT of the corresponding surgical segments was performed for three-dimensional reconstruction and evaluation of whether the vertebral arch root screw interfered with the proximal facet joint. The included cases were divided into an invasion group and a noninvasion group. Univariate analysis was used to screen the risk factors for pedicle screw invasion of the proximal facet joint after lumbar surgery, and the selected risk factors were included in the logistic model for multivariate analysis.

RESULTS

The single-factor analysis showed a significant difference in age, BMI, proximal facet joint angle, degenerative lumbar spondylolisthesis, and fixed segment (P < 0.1). Multifactor analysis of the logistic model showed a significant difference for age ≥ 50 years (P < 0.001, OR = 2.291), BMI > 28 kg/m2 (P < 0.001, OR = 2.548), degenerative lumbar spondylolisthesis (P < 0.001, OR = 2.187), gorge cleft lumbar relaxation (P < 0.001, OR = 2.410), proximal facet joint angle (35 ~ 45°: P < 0.001, OR = 3.151; > 45°: P < 0.001, OR = 3.578), and fixed segment (lower lumbar spine: P < 0.001, OR = 2.912).

CONCLUSION

Age (≥ 50 years old), BMI (> 28 kg/m2), proximal facet joint angle (35 ~ 45°, > 45°), degenerative lumbar spondylolisthesis, isthmic lumbar spondylolisthesis and fixed segment (lower lumbar spine) are independent risk factors for pedicle screw invasion of the proximal facet joint after lumbar surgery. Compared with degenerative lumbar spondylolisthesis, facet joint intrusion is more likely in isthmic lumbar spondylolisthesis.

Accuracy of Robot-Assisted Percutaneous Pedicle Screw Placement under Regional Anesthesia: A Retrospective Cohort Study

Background

Robot-assisted pedicle screw placement is usually performed under general anesthesia to keep the body still. The aim of this study was to compare the accuracy of the robot-assisted technique under regional anesthesia with that of conventional fluoroscopy-guided percutaneous pedicle screw placement under general anesthesia in minimally invasive lumbar fusion surgery.

Methods

This study recruited patients who underwent robot-assisted percutaneous endoscopic lumbar interbody fusion (PELIF) or fluoroscopy-guided minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) between December 2017 and February 2020 at a single center. Based on the method of percutaneous pedicle screw placement used, patients were divided into the robot-assisted under regional anesthesia (group RE-RO) and fluoroscopy-guided under general anesthesia (group GE-FLU) groups. The primary outcome measures were screw accuracy and the incidence of facet joint violation (FJV). Secondary outcome measures included X-ray and visual analogue scale (VAS) scores which were used to evaluate the degree of the postoperative pain at 4 hours and on postoperative days 1, 2, and 3. Intraoperative adverse events were also recorded.

Results

Eighteen patients were included in group RE-RO, and 23 patients were included in group GE-FLU. The percentages of clinically acceptable screws (Gertzbein and Robbins grades A and B) were 94.4% and 91.5%, respectively. There was no significant difference in the percentages of clinically acceptable screws (p=0.44) or overall Gertzbein and Robbins screw accuracy grades (p=0.35). Only the top screws were included in the analysis of FJVs. The percentages of FJV (Babu grades 1, 2, and 3) were 5.6% and 28.3%, respectively. This difference was statistically significant (p=0.01). Overall, the FJV grades in group RE-RO were significantly better than those in group GE-FLU (p=0.009). The mean fluoroscopy time for each screw in group RE-RO was significantly shorter than that in group GE-FLU (group RE-RO: 5.4 ± 1.9 seconds and group GE-FLU: 6.8 ± 2.0 seconds; p=0.03). The postoperative pain between the RE-RO and GE-FLU groups was not statistically significant. The intraoperative adverse events included 1 case of registration failure and 1 case of guide-wire dislodgment in group RE-RO, as well as 2 cases of screw misplacement in group GE-FLU. No complications related to anesthesia were observed.

Conclusion

Robot-assisted pedicle screw placement under regional anesthesia can be performed effectively and safely. The accuracy is comparable to the conventional technique. Moreover, this technique has the advantage of fewer FJVs and a lower radiation time.

The Rates and Risk Factors of Intra-Pedicular Accuracy and Proximal Facet Joint Violation for Single-Level Degenerative Lumbar Diseases: Cortical Bone Trajectory Versus Traditional Trajectory Pedicle Screw

STUDY DESIGN

A retrospective study.

OBJECTIVE

To compare the accuracy of pedicle screw placement and proximal facet joint violation (FJV) in single-level degenerative lumbar diseases using cortical bone trajectory (CBT) and traditional trajectory (TT) techniques, and analyze their possible risk factors.

SUMMARY OF BACKGROUND DATA

CBT screws have been utilized increasingly to improve cortical bone contact to prevent screw pullout and reduce approach-related morbidity. However, the studies on intra-pedicular accuracy and proximal FJV between the two methods are rare.

METHODS

A total of 40 patients who required single-level instruments were included in the retrospective study treated with the CBT-TLIF and the TT-TLIF at a 1:1 ratio from March 2019 to August 2020. The radiographic outcomes were the intra-pedicular accuracy and proximal FJV. Moreover, the possible risk factors were assessed using bivariate and multivariate analyses.

RESULTS

As for the intra-pedicular accuracy, 73 screws (91.3%) were classified as grade A, 7 screws (8.7%) classified as grade B in the CBT group. A total of 71 screws (88.8%) were graded A with remaining 8 screws (10.0%) graded B and 1 screw (1.2%) graded C in the TT group. The proportion of optimal and clinically acceptable screw positions in the two groups were not significantly different (P > 0.05). In addition, the rate of proximal FJV in CBT approach (8.3%) was significantly lower than that in the TT approach (35.0%) (P < 0.001). Multivariate analysis showed the TT insertion approach and facet angle ≥45° were the independent risk factors for proximal FJV, but no factors above affected intra-pedicular accuracy.

CONCLUSION

Compared with the TT approach in TLIF, the CBT approach showed similar intra-pedicular accuracy and remarkable superiority in proximal facet joint protection. Facet angle ≥45° is the independent risk factors for proximal FJV.Level of Evidence: 2.

Comparison of adjacent segment disease after minimally invasive versus open lumbar fusion: a minimum 10-year follow-up

OBJECTIVE

The object of this study was to compare, after a long-term follow-up, the incidence and features of adjacent segment disease (ASDis) following lumbar fusion surgery performed via an open technique using conventional interbody fusion plus transpedicular screw fixation or a minimally invasive surgery (MIS) using a tubular retractor together with percutaneous pedicle screw fixation.

METHODS

The authors conducted a retrospective chart review of patients with a follow-up period > 10 years who had undergone instrumented lumbar fusion at the L4-5 level between January 2004 and December 2010. The patients were divided into an open surgery group and MIS group based on the surgical method performed. Baseline characteristics and radiological findings, including factors related to ASDis, were compared between the two groups. Additionally, the incidence of ASDis and related details, including diagnosis, time to diagnosis, and treatment, were analyzed.

RESULTS

Among 119 patients who had undergone lumbar fusion at the L4-5 level in the study period, 32 were excluded according to the exclusion criteria. The remaining 87 patients were included as the final study cohort and were divided into an open group (n = 44) and MIS group (n = 43). The mean follow-up period was 10.50 (range 10.0-14.0) years in the open group and 10.16 (range 10.0-13.0) years in the MIS group. The overall facet joint violation rate was significantly higher in the open group than in the MIS group (54.5% vs 30.2%, p = 0.022). However, in terms of adjacent segment degeneration, there were no significant differences in corrected disc height, segmental angle, range of motion, or degree of listhesis of the adjacent segments between the two groups during follow-up. The overall incidence of ASDis was 33.3%, with incidences of 31.8% in the open group and 34.9% in the MIS group, showing no significant difference between the two groups (p = 0.822). Additionally, detailed diagnosis and treatment factors were not different between the two groups.

CONCLUSIONS

After a minimum 10-year follow-up, the incidence of ASDis did not differ significantly between patients who had undergone open fusion and those who had undergone MIS fusion at the L4-5 level.

Clinical and Radiographic Comparison Between Open Versus Minimally Invasive Transforaminal Lumbar Interbody Fusion With Bilateral Facetectomies

STUDY DESIGN

Age- and sex-matched cohort study.

OBJECTIVES

To compare outcomes after open versus minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) with bilateral facetectomies.

METHODS

We retrospectively compared patients who underwent single- or 2-level MIS-TLIF with an age- and sex-matched open-TLIF cohort. Surgical data was collected for operative time, estimated blood loss (EBL), and drain use. Clinical outcomes included the Visual Analog Scale (VAS), Oswestry Disability Index (ODI), length of stay (LOS), complications, and reoperations. Lumbar radiographs were measured for changes in global lumbar lordosis (LL) and segmental lordosis (SL).

RESULTS

Between 2016 and 2020, 38 MIS-TLIF patients were compared with 38 open-TLIF patients. No subfascial drain was used in the MIS-TLIF group (P < .001). The MIS-TLIF group had longer operative time (310.8 vs 276.5 minutes; P = .046) but less EBL (282.4 vs 420.8 mL; P = .007). LOS (P = .15), complication rates (P = .50), and revision rates (P = .17) were equivalent. VAS and ODI improved but did not differ between groups. In the open-TLIF group, LL and SL were restored or improved in 81.6% and 86.9% of cases, respectively. In the MIS-TLIF group, LL and SL were restored or improved in 86.8% and 97.4% of cases, respectively. There were no differences in changes in LL and SL between groups.

CONCLUSIONS

Compared with the age- and sex-matched open-TLIF cohort, patients undergoing MIS-TLIF had reduced EBL and subfascial drain use but increased operative time. There were no differences in complications, reoperations, or LOS. Both groups demonstrated improvement in VAS and ODI. MIS-TLIF with bilateral facetectomies provided equivalent improvements in global and segmental LL.