Objective: Cervical spine surgery presents unique technical challenges because of the small and complex anatomy of the cervical vertebrae and the high risk of neurovascular complications. Recent advances in 3-dimensional (3D) printing and navigation technologies have been introduced to improve screw placement accuracy, reduce surgical risk, and potentially shorten operative time. In this systematic review, we aimed to summarize currently available evidence and to describe selected studies evaluating 3D-printed navigation templates and intraoperative computer-assisted navigation systems for cervical pedicle screw placement. Methods: This study was conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines. A literature search was performed for publications published between 2019 and 2024 using the following search terms: (“cervical spine” OR “navigation-assisted system”) OR (“3D printing template” OR “computer-assisted system”). A total of 130 articles met the initial screening criteria, of which 8 studies were included in the final analysis after application of predefined inclusion and exclusion criteria. Results: Eight studies were included in the final systematic review and network meta-analysis. The findings indicated that 3D-printed templates demonstrated higher accuracy, reaching up to 95.8% (risk ratio [RR], 1.17), and fewer deviations compared with computer-assisted navigation (RR, 1.05) and traditional techniques (RR, 1.0). Computer-assisted navigation showed greater heterogeneity across studies. However, no statistically significant difference in outcomes was observed between 3D-printed templates and computer-assisted navigation systems. Conclusion Navigation-assisted cervical pedicle screw fixation is effective, and both 3D-printed templates and computer-assisted navigation techniques provide advantages in terms of accuracy and procedural safety.

Methods: The hemodynamic response to postural changes (supine to sitting and standing) was evaluated preoperatively and at 6, 12, 24, and 48 hours postoperatively in 30 patients who underwent single-level OLIF versus MIS-TLIF within an ERAS protocol. The protocols were evaluated sequentially, beginning with a change from supine to sitting, followed immediately by standing, with the patient remaining in the standing position for 3 minutes for evaluation. Results: This study compared OLIF and MIS-TLIF in 60 patients and found no significant differences in baseline characteristics. The OLIF group demonstrated greater hemodynamic stability within 6 hours after surgery, exhibiting smaller decreases in systolic blood pressure and mean arterial pressure, along with reduced fluid responsiveness compared to the MIS-TLIF group. Both groups of patients exhibited comparable heart rates and cardiac output stabilization over time. Clinically, OLIF resulted in greater postoperative back pain relief, lower blood loss (45±7.31 mL vs. 99.33±14.13 mL), and higher postoperative hemoglobin levels compared to MIS-TILF. Operative time, hospital stay, and complication rates were comparable between the OLIF and MIS-TLIF groups. Conclusions OLIF was associated with improved hemodynamic parameters within 6 hours postoperatively, less blood loss, and improved pain relief compared to MIS-TLIF, while both procedures demonstrated similar operative times, hospital stays, and no complications.

Our research examines the learning curves of various minimally invasive lumbar surgeries to determine the benefits and challenges they pose to both surgeons and patients. The advent of microsurgical techniques since the 1960s, including advances in fluoroscopic navigation and intraoperative computed tomography, has significantly shifted spinal surgery from open to minimally invasive methods. This study critically evaluates surgical duration, intraoperative conversions to open surgery, and complications as primary parameters to gauge these learning curves. Through a comprehensive literature search up to March 2024, involving databases PubMed, Cochrane Library, and Web of Science, this paper identifies a steep learning curve associated with these surgeries. Despite their proven advantages in reducing recovery time and surgical trauma, these procedures require surgeons to master advanced technology and equipment, which can directly impact patient outcomes. The study underscores the need for well-defined learning curves to facilitate efficient training and enhance surgical proficiency, especially for novice surgeons. Moreover, it addresses the implications of technology on surgical accuracy and the subsequent effects on complication rates, providing insights into the complex dynamics of adopting new surgical innovations in spinal health care.

Objective: To compare the clinical and radiographic outcomes following lateral lumbar interbody fusion (LLIF) between direct and indirect decompression in the treatment of patients with degenerative lumbar diseases. Methods: Patients who underwent single-level LLIF were randomized into 2 groups: direct decompression (group D) and indirect decompression (group I). Clinical outcomes including the Oswestry Disability index and visual analogue scale of back and leg pain were collected. Radiographic outcomes including cross-sectional area (CSA) of thecal sac, disc height, foraminal height, foraminal area, fusion rate, segmental, and lumbar lordosis were measured. Results: Twenty-eight patients who met the inclusion criteria were eligible for the analysis, with a distribution of 14 subjects in each group. The average age was 66.1 years. Postoperatively, significant improvements were observed in all clinical parameters. However, these improvements did not show significant difference between both groups at all follow-up periods. All radiographic outcomes were not different between both groups, except for the increase in CSA which was significantly greater in group D (77.73 ± 20.26 mm2 vs. 54.32 ± 35.70 mm2, p = 0.042). Group I demonstrated significantly lower blood loss (68.13 ± 32.06 mL vs. 210.00 ± 110.05 mL, p < 0.005), as well as shorter operative time (136.35 ± 28.07 minutes vs. 182.18 ± 42.67 minutes, p = 0.002). Overall complication rate was not different. Conclusion Indirect decompression through LLIF results in comparable clinical improvement to LLIF with additional direct decompression over 1-year follow-up period. These findings suggest that, for an appropriate candidate, direct decompression in LLIF might not be necessary since the ligamentotaxis effect achieved through indirect decompression appears sufficient to relieve symptoms while diminishing blood loss and operative time.

Objective: Oblique lateral interbody fusion (OLIF) is a minimally invasive procedure for stabilizing the spine and indirectly decompressing the neural elements. There is sparse data on unsatisfactory outcomes that require additional interventions (surgery or intervention) after OLIF. This study aimed to identify the causes, and risk factors of these reintervention. Methods: This was a single-center retrospective study of the patients who underwent the OLIF procedure from June 2016 to March 2023. Several clinical and radiographic parameters were studied. We also analyzed associations between several potential risk factors and the reintervention following OLIF. Results: A total of 231 patients were included. Over an average of 2.5 years of follow-up, 28 patients (12.1%) required a reintervention. Adjacent segment disease (ASD) was the most common cause of reintervention. The risk factors associated with reintervention were previous surgery (adjusted odds ratio [aOR], 4.44; 95% confidence interval [CI], 1.21–16.33; p=0.02) and high preoperative Oswestry Disability Index (ODI) scores (aOR, 1.04; 95% CI, 1.00–1.08; p=0.03). Although increasing the duration of follow-up was not statistically significant, the 95% CI was consistent with an increased risk of reintervention with longer follow-up (OR, 1.18; 95% CI, 0.94–1.50). Conclusion This study showed that patients with prior lumbar surgery and high preoperative ODI scores were more likely to require additional intervention after the OLIF procedure. In addition, an increasing duration of follow-up was associated with an increased risk of reintervention. The most common reason for reintervention was ASD after OLIF.

Objective: Oblique lumbar interbody fusion (OLIF), performed using a retroperitoneal approach, can lead to complications related to the approach, such as lumbar sympathetic chain injury (LSCI). Although LSCI is a common complication of OLIF, its reported incidence varies across studies due to an absence of specific diagnostic criteria. Moreover, research on the risk factors of postoperative sympathetic chain injuries after OLIF remains limited. Therefore, this study aimed to describe the incidence, and identify independent risk factors for LSCI, in patients with degenerative lumbar spinal diseases who underwent OLIF. Methods: Between October 2020 and August 2023, a retrospective review was conducted at our institute on 200 patients who underwent OLIF at 1 to 4 consecutive spinal levels (L1–5) for degenerative spinal diseases including spinal stenosis, spondylolisthesis, degenerative scoliosis. We excluded those with infections, trauma, tumors, and lower extremity edema/warmth due to other causes. The patients were categorized into 2 groups: those with and without LSCI symptoms. Demographic data, operative data, and pre- and postoperative parameters were evaluated for their association with LSCI using a univariate logistic regression model. Variables with a p-value <0.1 in the univariate analysis were included in a multivariate model to identify the independent risk factors. Results: Thirty-five of 200 patients (17.5%) developed LSCI symptoms after OLIF. Multivariate logistic regression analysis indicated that prolonged retraction time, particularly exceeding 31.5 miniutes, remained an independent risk factor (adjusted odds ratio, 12.59; p<0.001). Conclusion This study demonstrated that prolonged retraction time was an independent risk factor for LSCI following OLIF, particularly when it exceeded 31.5 minutes. Protecting the lumbar sympathetic chain during surgery and minimizing retraction time are crucial to avoiding LSCI following OLIF.

Objective: To compare clinical and radiographic outcomes between 2 motion preservation surgeries, cervical disc replacement (CDR) and posterior endoscopic cervical decompression (PECD), for unilateral cervical radiculopathy. Methods: Between February 2018 and December 2020, 60 patients with unilateral cervical radiculopathy who underwent either CDR or PECD were retrospectively recruited as matched pairs. Clinical outcomes included visual analogue scale (VAS) scores for neck and arm pain, Neck Disability Index (NDI), and satisfaction rates. The radiographic outcome was index level motion. Intraoperative data, complications, and hospital stay were collected. Preoperative and postoperative outcomes were compared. Results: Patients undergoing CDR or PECD were included, with 30 cases in each group. Matched pairs were compared in terms of demographic data and preoperative measurements. CDR was associated with shorter operative times, whereas PECD resulted in less intraoperative blood loss. The total complication rate was 5%. NDI and VAS for neck and arm were significantly improved in both groups, with no significant differences between the 2 groups. Satisfaction rates of good and excellent exceeded 87% in both groups. CDR was superior to PECD in the restoration of disc height. Early postoperative follow-up showed no significant difference in terms of index level motion. PECD demonstrated significantly shorter hospital stays and quicker return-to-work times (p<0.05). Conclusion PECD achieved equivalent clinical and radiologic outcomes compared with CDR when the certain criteria for surgery were met. Both techniques demonstrated the potential to maintain index level motion. Additionally, PECD resulted in less blood loss, shorter hospital stays, and faster return-to-work times. Conversely, CDR offered shorter operative times and better restoration of disc height.

Methods: This study analyzed 432 open-mouth (odontoid) radiographic views of cervical spine X-ray images obtained from dataset repositories, which were used in developing ANN models based on the convolutional neural network theory. All the images contained diagnostic information, including 216 radiographic images of individuals with normal odontoid processes and 216 images of patients with acute odontoid fractures. The model classified each image as either showing an odontoid fracture or not. Specifically, 70% of the images were training datasets used for model training, and 30% were used for testing. KNIME’s graphic user interface-based programming enabled class label annotation, data preprocessing, model training, and performance evaluation. Results: The graphic user interface program by KNIME was used to report all radiographic X-ray imaging features. The ANN model performed 50 epochs of training. The performance indices in detecting odontoid fractures included sensitivity, specificity, F-measure, and prediction error of 100%, 95.4%, 97.77%, and 2.3%, respectively. The model’s accuracy accounted for 97% of the area under the receiver operating characteristic curve for the diagnosis of odontoid fractures. Conclusions The ANN models with the KNIME Analytics Platform were successfully used in the computer-assisted diagnosis of odontoid fractures using radiographic X-ray images. This approach can help radiologists in the screening, detection, and diagnosis of acute odontoid fractures.

Our research examines the learning curves of various minimally invasive lumbar surgeries to determine the benefits and challenges they pose to both surgeons and patients. The advent of microsurgical techniques since the 1960s, including advances in fluoroscopic navigation and intraoperative computed tomography, has significantly shifted spinal surgery from open to minimally invasive methods. This study critically evaluates surgical duration, intraoperative conversions to open surgery, and complications as primary parameters to gauge these learning curves. Through a comprehensive literature search up to March 2024, involving databases PubMed, Cochrane Library, and Web of Science, this paper identifies a steep learning curve associated with these surgeries. Despite their proven advantages in reducing recovery time and surgical trauma, these procedures require surgeons to master advanced technology and equipment, which can directly impact patient outcomes. The study underscores the need for well-defined learning curves to facilitate efficient training and enhance surgical proficiency, especially for novice surgeons. Moreover, it addresses the implications of technology on surgical accuracy and the subsequent effects on complication rates, providing insights into the complex dynamics of adopting new surgical innovations in spinal health care.

Objective: To compare the clinical and radiographic outcomes following lateral lumbar interbody fusion (LLIF) between direct and indirect decompression in the treatment of patients with degenerative lumbar diseases. Methods: Patients who underwent single-level LLIF were randomized into 2 groups: direct decompression (group D) and indirect decompression (group I). Clinical outcomes including the Oswestry Disability index and visual analogue scale of back and leg pain were collected. Radiographic outcomes including cross-sectional area (CSA) of thecal sac, disc height, foraminal height, foraminal area, fusion rate, segmental, and lumbar lordosis were measured. Results: Twenty-eight patients who met the inclusion criteria were eligible for the analysis, with a distribution of 14 subjects in each group. The average age was 66.1 years. Postoperatively, significant improvements were observed in all clinical parameters. However, these improvements did not show significant difference between both groups at all follow-up periods. All radiographic outcomes were not different between both groups, except for the increase in CSA which was significantly greater in group D (77.73 ± 20.26 mm2 vs. 54.32 ± 35.70 mm2, p = 0.042). Group I demonstrated significantly lower blood loss (68.13 ± 32.06 mL vs. 210.00 ± 110.05 mL, p < 0.005), as well as shorter operative time (136.35 ± 28.07 minutes vs. 182.18 ± 42.67 minutes, p = 0.002). Overall complication rate was not different. Conclusion Indirect decompression through LLIF results in comparable clinical improvement to LLIF with additional direct decompression over 1-year follow-up period. These findings suggest that, for an appropriate candidate, direct decompression in LLIF might not be necessary since the ligamentotaxis effect achieved through indirect decompression appears sufficient to relieve symptoms while diminishing blood loss and operative time.