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

Single Position Prone Lateral Lumbar Interbody Fusion: A Review of the Current Literature

PURPOSE OF REVIEW

Spinal fusion, vital for treating various spinal disorders, has evolved since the introduction of the minimally invasive Lateral Lumbar Interbody Fusion (LLIF) by Pimenta in 2001. Traditionally performed in the lateral decubitus position, LLIF faces challenges such as intraoperative repositioning, neurological complications, and lack of access to lower lumbar levels. These challenges lead to long surgery times, increased rates of perioperative complications, and increased costs. The more recently popularized prone lateral approach mitigates these issues primarily by eliminating patient repositioning, thereby enhancing surgical efficiency, and reducing operative times. This review examines the progression of spinal fusion techniques, focusing on the advantages and recent findings of the prone lateral approach compared to the traditional LLIF.

RECENT FINDINGS

The prone lateral approach has shown improved patient outcomes, including lower blood loss and shorter hospital stays, and has been validated by multiple studies for its safety and efficacy compared to the LLIF approach. Significant enhancements in postoperative metrics, such as the Oswestry Disability Index, Visual Analog Scale, and radiological improvements have been noted. Comparatively, the prone lateral approach offers superior segmental lordosis correction and potentially better subjective outcomes than the lateral decubitus position. Despite these advances, both techniques present similar risks of neurological complications. Overall, the prone lateral approach has emerged as a promising alternative in lumbar interbody fusion, combining efficiency, safety, and improved clinical outcomes.

[Treatment of thoracolumbar tuberculosis with robot-assisted and minimally invasive access via transforaminal expansion approach]

Objective

To investigate the feasibility and effectiveness of robot-assisted posterior minimally invasive access in treatment of thoracolumbar tuberculosis via transforaminal expansion approach.

Methods

A clinical data of 40 patients with thoracolumbar tuberculosis admitted between January 2017 and May 2022 and met the selection criteria was retrospectively analyzed. Among them, 15 cases were treated with robot-assisted and minimally invasive access via transforaminal expansion approach for lesion removal, bone graft, and internal fixation (robotic group), and 25 cases were treated with traditional transforaminal posterior approach for lesion removal and intervertebral bone grafting (traditional group). There was no significant difference in the baseline data between the two groups ( P>0.05) in terms of gender, age, lesion segment, and preoperative American Spinal Injury Association (ASIA) grading, Cobb angle, visual analogue scale (VAS) score, erythrocyte sedimentation rate (ESR), and C reactive protein (CRP). The outcome indicators were recorded and compared between the two groups, including operation time, intraoperative bleeding volume, hospital stay, postoperative bedtime, complications, ESR and CRP before operation and at 1 week after operation, the level of serum albumin at 3 days after operation, VAS score and ASIA grading of neurological function before operation and at 6 months after operation, the implant fusion, fusion time, Cobb angle of the lesion, and the loss of Cobb angle observed by X-ray films and CT. The differences of ESR, CRP, and VAS score (change values) between pre- and post-operation were calculated and compared.

Results

Compared with the traditional group, the operation time and intraoperative bleeding volume in the robotic group were significantly lower and the serum albumin level at 3 days after operation was significantly higher ( P<0.05); the postoperative bedtime and the length of hospital stay were also shorter, but the difference was not significant ( P>0.05). There were 2 cases of poor incision healing in the traditional group, but no complication occurred in the robotic group, and the difference in the incidence of complication between the two groups was not significant ( P>0.05). There were significant differences in the change values of ESR and CRP between the two groups ( P<0.05). All Patients were followed up, and the follow-up time was 12-18 months (mean, 13.0 months) in the traditional group and 12-16 months (mean, 13.0 months) in the robotic group. Imaging review showed that all bone grafts fused, and the difference in fusion time between the two groups was not significant ( P>0.05). The difference in Cobb angle between the pre- and post-operation in the two groups was significant ( P<0.05); and the Cobb angle loss was significant more in the traditional group than in the robotic group ( P<0.05). The VAS scores of the two groups significantly decreased at 6 months after operation when compared with those before operation ( P<0.05); the difference in the change values of VAS scores between the two groups was not significant ( P>0.05). There was no occurrence or aggravation of spinal cord neurological impairment in the two groups after operation. There was a significant difference in ASIA grading between the two groups at 6 months after operation compared to that before operation ( P<0.05), while there was no significant difference between the two groups ( P>0.05).

Conclusion

Compared with traditional posterior open operation, the use of robot-assisted minimally invasive access via transforaminal approach for lesion removal and bone grafting internal fixation in the treatment of thoracolumbar tuberculosis can reduce the operation time and intraoperative bleeding, minimizes surgical trauma, and obtain definite effectiveness.

Effects of the Severity of Stenosis on Clinical Outcomes of Indirect Decompression Using Oblique Lumbar Interbody Fusion

Background: No consensus has been reached regarding the efficacy of indirect decompression through oblique lumbar interbody fusion (OLIF) in severe lumbar spinal stenosis (LSS). This study investigated the impact of preoperative magnetic resonance imaging (MRI)-based grading of central and foraminal stenosis on OLIF outcomes in LSS patients and identified risk factors for postoperative clinical dissatisfaction. Methods: We retrospectively reviewed LSS patients who underwent OLIF with a minimum 1-year follow-up. Clinical scores obtained preoperatively and at 3, 6, 12, and 24 months postoperatively were analyzed using the substantial clinical benefit (SCB) framework. The severity of central and foraminal stenosis in the initial MRI was assessed through qualitative grading systems. Results: Among the 145 patients, with a mean follow-up of 33.7 months, those with severe central stenosis showed a significantly higher proportion of patients achieving SCB in the visual analog scale for leg pain (94.5% versus 83.1%; p = 0.044) at one year postoperatively than those without. However, those with severe foraminal stenosis showed significantly higher Oswestry Disability Index (ODI) scores (p = 0.024), and lower walking ability scores in the Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ) (p = 0.004) at one year postoperatively than those without. The presence of a foraminal osteophyte of the superior articular process (SAP) was a significant risk factor responsible for not achieving SCB in ODI and walking ability in JOABPEQ at one year postoperatively (odds ratio: 0.20 and 0.22, respectively). Conclusions: After OLIF, patients with severe central stenosis showed clinical outcomes comparable to those without. The improvement in ODI and walking ability in JOABPEQ was limited in patients with severe foraminal stenosis. Surgeons should consider direct decompression in cases with the presence of foraminal osteophytes of SAP.

In Vivo Comparison of Positive Microbial Culture by Wound Irrigation Methods: Biportal Endoscopic Versus Open Microscopic Transforaminal Lumbar Interbody Fusion

STUDY DESIGN

Prospective cohort study.

OBJECTIVE

This study aimed to evaluate the risk factors and prevalence of intraoperative contamination (IoC) through the microbial culture of superficial and deep samples obtained during surgery.

SUMMARY OF BACKGROUND DATA

Surgical site infection (SSI) in spinal surgery is a serious complication. The prevalence of IoC may differ based on surgical approach and technique, even in the setting of the same procedure.

MATERIALS AND METHODS

In this in vivo study, microbial cultivation was performed with superficial (ligamentum flavum, LF) and deep (nucleus pulposus, NP) surgical specimens to evaluate IoC in 132 patients undergoing single-level transforaminal lumbar interbody fusion (TLIF). Biportal endoscopic -TLIF was performed under continuous wound irrigation (group A, n=66), whereas open microscopic (OM) TLIF was performed under intermittent wound irrigation (group B, n=66). LF and NP specimens were homogenized, gram stained, and cultured in aerobic and anaerobic media for 14 days. Microbial culture results and the occurrence of SSI in the two groups were assessed. The χ 2 test and Fisher exact test were used to determine significant differences among categorical variables. Logistic regression analysis was used to assess the influence of patient characteristics on the prevalence of positive microbial cultures.

RESULTS

Of the 132 patients, 34 (25.8%) had positive microbial cultures, and positive culture required an incubation period of 72 hours to 2 weeks in all these patients except for three. Overall, positive culture was significantly higher in group B than in group A ( P =0.029). The subgroups of LF- and NP-positive cultures were 18.18% (n=24) and 12.88% (n=17), respectively; the SSI was 0.76% (n=1). Group A had a significantly lower subgroup of NP-positive culture than group B ( P =0.035). OM technique was an independent risk factor associated with overall positive culture ( P <0.05). The most common microorganism was Cutibacterium acnes ( C. acnes ).

CONCLUSIONS

Biportal endoscopic-TLIF with continuous wound irrigation showed significantly lower overall and NP-positive cultures than OM-TLIF with intermittent irrigation. The most common strain of positive culture was C. acnes .

LEVEL OF EVIDENCE

2.

Pushing the Limits of Minimally Invasive Spine Surgery-From Preoperative to Intraoperative to Postoperative Management

The introduction of minimally invasive surgery ushered in a new era of spine surgery by minimizing the undue iatrogenic injury, recovery time, and blood loss, among other complications, of traditional open procedures. Over time, technological advancements have further refined the care of the operative minimally invasive spine patient. Moreover, pre-, and postoperative care have also undergone significant change by way of artificial intelligence risk stratification, advanced imaging for surgical planning and patient selection, postoperative recovery pathways, and digital health solutions. Despite these advancements, challenges persist necessitating ongoing research and collaboration to further optimize patient care in minimally invasive spine surgery.

Treatment Concept and Technical Considerations of Biportal Endoscopic Spine Surgery for Lumbar Spinal Stenosis

Decompression is a major component of surgical procedures for degenerative lumbar spinal stenosis (LSS). In addition to sufficient decompression to guarantee the relief of neurological pain, compensating surgical instability after wider laminectomy and foraminotomy and instrumentation with caging and fusion with grafting are performed to secure or restore the foraminal dimension and correct coronal/sagittal imbalance for longer survival of the adjacent segment. Endoscopic spinal surgery (ESS) has been developed under the flag of successful decompression while preserving structural integrity as much as possible with the help of magnification and illumination. ESS provides a technical possibility and feasibility for solving LSS by decompression alone. Recently, many endoscopic trials have been conducted to overcome conventional surgical treatment that requires wider dissection, escape inevitable complications from surgical damage, and compensate for the fusion technique. However, biportal ESS has some technical limitations, including clinical difficulties in accessibility for more moderate to severe stenosis and challenges for complicated conditions with segmental ventral slip, isthmic defect, stenosis combined with foraminal stenosis or foraminal disk rupture, or degenerative segmental scoliosis with disk height collapsing and endplate fatigue fracture. Because decompression alone is a skill for eliminating pathologies, there is no function of preserving degenerative structure or stopping the recurrence of disk degeneration or subsidence. This review of clinical reports investigated the possibility of biportal ESS for treating degenerative lumbar disorders by sufficient decompression and adequate elimination of various pathologies and decreasing technical complications. The results of this study may help develop better innovative spinal surgical techniques in the near future.

Current Trends in Artificial Intelligence-Assisted Spine Surgery: A Systematic Review

This systematic review summarizes existing evidence and outlines the benefits of artificial intelligence-assisted spine surgery. The popularity of artificial intelligence has grown significantly, demonstrating its benefits in computer-assisted surgery and advancements in spinal treatment. This study adhered to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses), a set of reporting guidelines specifically designed for systematic reviews and meta-analyses. The search strategy used Medical Subject Headings (MeSH) terms, including "MeSH (Artificial intelligence)," "Spine" AND "Spinal" filters, in the last 10 years, and English- from January 1, 2013, to October 31, 2023. In total, 442 articles fulfilled the first screening criteria. A detailed analysis of those articles identified 220 that matched the criteria, of which 11 were considered appropriate for this analysis after applying the complete inclusion and exclusion criteria. In total, 11 studies met the eligibility criteria. Analysis of these studies revealed the types of artificial intelligence-assisted spine surgery. No evidence suggests the superiority of assisted spine surgery with or without artificial intelligence in terms of outcomes. In terms of feasibility, accuracy, safety, and facilitating lower patient radiation exposure compared with standard fluoroscopic guidance, artificial intelligence-assisted spine surgery produced satisfactory and superior outcomes. The incorporation of artificial intelligence with augmented and virtual reality appears promising, with the potential to enhance surgeon proficiency and overall surgical safety.

Educational effects of and satisfaction with mixed-reality-based major trauma care simulator: A preliminary evaluation

Mixed reality (MR) is a hybrid system that projects virtual elements into reality. MR technology provides immersive learning using various real-world tools. However, studies on educational programs using MR are scarce. This study aimed to investigate the educational effects of and satisfaction with an MR-based trauma decision-making simulator. A total 40 of trainees self-selected to participate in this study. All of them participated in the MR trauma simulator for approximately 30 minutes and conducted voluntary learning without any external help. Declarative knowledge, measured using 20 multiple-choice questions, was assessed before and after MR trauma training. To confirm the educational effect, test scores before and after MR trauma training were compared using a paired t-test. Student satisfaction after training was measured using a ten-item questionnaire rated on a five-point Likert scale. A pretest-posttest comparison yielded a significant increase in declarative knowledge. The percentage of correct answers to multiple choice questions increased (from a mean of 42.3, SD 12.4-54.8, SD 13) after the MR-based trauma assessment and treatment training (P < .001). Of the participants, 79.45% were satisfied with the overall experience of using the MR simulator. This study demonstrated a meaningful educational effect of the MR-based trauma training system even after a short training time.

A Randomized Controlled Trial of Vertebral Body Decompression Procedure Versus Conservative Treatment for Painful Vertebral Compression Fracture

Background: Traditional treatment modalities for vertebral compression fractures (VCFs) include bed rest, pain medications, muscle relaxants, back braces, and physical therapy. In cases where conservative treatment proves ineffective, a new procedure called core decompression of the vertebral body is explored. Core decompression of the vertebral body has the potential to lower and stabilize the intraosseous pressure, resulting in enhanced blood circulation, which contributes to pain reduction. In this trial, we evaluated the efficacy of core decompression of the vertebral body in patients with painful VCFs compared with conventional conservative treatment. Methods: This prospective randomized controlled trial was conducted at a tertiary education hospital between June 2017 and May 2020. The participants were randomly assigned in a 1:1 ratio to one of two treatment groups: the core decompression group and the conservative treatment group. The primary outcome measure was the visual analog scale (VAS) pain score of the back 3 months after the procedure. Secondary outcome measures included the Oswestry Disability Index (ODI) for lumbar disabilities, the European Quality of Life-5 Dimensions (EQ-5D) score for quality of life, and radiographic outcomes such as changes in compression rate. Results: All patients underwent the assigned intervention (48 core decompression and 50 conservative treatments). At both 1 month and 3 months, there were no significant differences between the core decompression group and conservative treatment group in VAS pain score (adjusted treatment effect: -0.1 and 2.0; 95% confidence interval [CI]: -7.5 to 7.3 and -5.6 to 9.6; p = 0.970 and p = 0.601, respectively). In addition, there were no significant inter-group differences in ODI and EQ-5D scores throughout the follow-up period (p = 0.917 and 0.704, respectively). Conclusion: Core decompression of the vertebral body did not demonstrate any significant improvement in pain and disability compared to conventional conservative treatment.

A Beginner's Perspective on Biportal Endoscopic Spine Surgery in Single-Level Lumbar Decompression: A Comparative Study with a Microscopic Surgery

Background

The application of biportal endoscopic spinal surgery (BESS) in spine surgery is increasing. However, the clinical results of related studies have been inconsistent. In this study, the perioperative and clinical outcomes of two techniques in single-level lumbar decompression surgery were compared using the perspective of a spine surgeon experienced in microscopic surgery but inexperienced in BESS.

Methods

This is a retrospective study performed with prospectively collected data. From April 2019, 50 consecutive patients who underwent a single-level lumbar decompression surgery with BESS were evaluated. Additionally, the data of 150 consecutive patients who underwent the same microscopic surgery before April 2019 were collected. We performed 1 : 1 ratio propensity score matching for these two groups to adjust for baseline variables. The postoperative patient-reported outcome measures included the Oswestry Disability Index (ODI) and numeric rating scale for the back and leg preoperatively and at 6 months after surgery. The laboratory data (C-reactive protein [CRP, mg/L] and hemoglobin [Hb, g/dL]) were measured preoperatively and 3 times (1, 2, and 3 or 4 days) postoperatively. In these periods, the peak and lowest CRP and Hb concentrations were evaluated. The perioperative outcomes, operation time (from skin incision to dressing), length of hospital stay, drainage (for 24 hours after surgery), and surgery-related complications were also evaluated.

Results

Forty-seven patients (27 men and 20 women) were included in each group. The postoperative 6-month ODI was significantly lower in the BESS group than in the microscope group (6.90 ± 5.98 vs. 11.54 ± 9.70). The peak CRP concentration (16.63 ± 19.41 vs. 42.40 ± 37.73, p < 0.001) and CRP increment (peak CRP minus preoperative CRP, 14.69 ± 19.47 vs. 40.71 ± 37.32, p < 0.001) were significantly higher in the microscope group. Operation time (83.72 ± 35.71 vs. 70.27 ± 23.24, p = 0.047) was significantly longer in the BESS group. Surgery-related complications were found in 6 and 3 cases in the BESS group (3 revisions, 2 dural tears, and 1 conversion to open surgery) and microscope group (2 revisions and 1 hematoma), respectively.

Conclusions

BESS as a new technique resulted in satisfying short-term outcomes. It was a well-tolerated option for surgical treatment of single-level lumbar degenerative disease. The relatively high incidence of recurrence at the index level and incidental dural tears should be considered for surgeons new to BESS; however, these were manageable complications.

Biportal endoscopic discectomy versus tubular microscopic discectomy for treating single-level lumbar disc herniation in obese patients: a multicenter, retrospective analysis

PURPOSE

In microscopic lumbar discectomy in obese patients, a correlation is found between the operation time and increase in estimated blood loss according to the increase in body mass index; however, no studies have investigated the outcomes of biportal endoscopic lumbar discectomy in obese patients. Therefore, this study aimed to compare the clinical and radiographic outcomes of microscopic and endoscopic discectomy in obese patients with lumbar herniated discs.

METHODS

In this multicenter, retrospective study, clinical and radiological data were compared and analyzed in 73 obese patients with a body mass index of > 30 kg/m2 who underwent microscopic or biportal endoscopic lumbar discectomy. Clinical data on the visual analog scale (VAS), Oswestry disability index (ODI), and EuroQol-5D (EQ-5D) scores were measured, and radiological data were obtained using magnetic resonance imaging (MRI).

RESULTS

This study enrolled 43 patients who underwent microscopic discectomy and 30 who underwent biportal endoscopic discectomy. The VAS, ODI, and EQ-5D scores in both groups improved after surgery compared with those before surgery, although there was no difference between the two groups. Although there was a difference in the incidence of recurrent disc herniation confirmed by MRI after surgery, no difference was found in the number of patients requiring surgery between the two groups.

CONCLUSION

In obese patients with lumbar disc herniation that was not improved with conservative treatment, no significant clinical or radiological differences in outcomes were noted between microscopic and biportal endoscopic surgery methods. In contrast, minor complications were less common in the biportal group.

When Should Spinal Surgery Be Considered for Spinal Metastasis from Non-Small Cell Lung Cancer?-Propensity Score Matched Study between Surgery with Radiotherapy and Radiotherapy Alone

(1) Background: Although metastatic spine disease is increasing, the debate on therapeutic modality remains due to the heterogeneity of tumors and patients. This study aims to evaluate the efficacies of surgery and risk factors for patients' survival from potentially unstable spinal metastasis of non-small cell lung cancer; (2) Methods: Twenty-two patients undergoing surgery and radiotherapy (group I) were compared with 22 patients undergoing radiotherapy alone (group II) using propensity score matching in a 1-to-1 format. Clinical outcomes included the performance status and ambulatory status. In addition, independent risk factors for patients' survival were evaluated, including the molecular targeted therapy for mutations; (3) Results: deterioration in neurologic status was only observed in group II compared to group I (22.7% vs. 0%, p-value = 0.018). In addition, five patients in the surgery group showed improved Frankel grades. Regarding the patients' survival, a smoking history of more than ten pack-years (hazard ratio (HR) = 12.18), worse performance status (HR = 6.86), and absence of mutations (HR = 3.39) were the independent risk factors; (4) Conclusions: Spinal surgery with radiotherapy could have advantages for improving the neurologic status including ambulation for potentially unstable spine due to metastasis. Thus, surgery should be considered for patients with a longer life expectancy resulting from better performance status and use of the targeted therapy.

Underweight and risk of fractures in adults over 40 years using the nationwide claims database

We aimed to investigate how underweight affects the incidence of fractures, as well as the influence of cumulative, longitudinal periods of low body mass index (BMI) and changes in body weight on fracture development. Data on adults aged 40-year and over who had three health screenings between January 1, 2007, and December 31, 2009 were used to determine the incidence of new fractures. The hazard ratios (HRs) for new fractures depending on BMI, total cumulative number of underweight, and weight change over time were calculated using Cox proportional hazard analysis. In this study, 15,955 (2.8%) of the 561,779 adults were diagnosed with fractures more than once over three health examinations. The fully adjusted HR for fractures in underweight individuals was 1.173 (95% Confidence interval [CI] 1.093-1.259). Underweight individuals diagnosed only once, twice, or three times had an adjusted HR of 1.227 (95%CI 1.130-1.332), 1.174 (95%CI 1.045-1.319), and 1.255 (95%CI 1.143-1.379), respectively. Although the adjusted HR was higher in adults who consistently had underweight (HR; 1.250 [95%CI 1.146-1.363]), those with underweight had an increased risk of fractures regardless of weight change (HR; 1.171 [95%CI 1.045-1.312], and 1.203[95%CI 1.075-1.346]). Underweight is a risk factor for fractures in adults over the age of 40 years, even if they returned to normal weight.

Biportal endoscopic extraforaminal lumbar interbody fusion using a 3D-printed porous titanium cage with large footprints: technical note and preliminary results

PURPOSE

The aim of this study was to introduce biportal endoscopic extraforaminal lumbar interbody fusion (BE-EFLIF), which involves insertion of a cage through a more lateral side as compared to the conventional corridor of transforaminal lumbar interbody fusion. We described the advantages and surgical steps of 3D-printed porous titanium cage with large footprints insertion through multi-portal approach, and preliminary results of this technique.

METHODS

This retrospective study included 12 consecutive patients who underwent BE-EFLIF for symptomatic single-level lumbar degenerative disease. Clinical outcomes, including a visual analog scale (VAS) for back and leg pain and the Oswestry disability index (ODI), were collected at preoperative months 1 and 3, and 6 months postoperatively. In addition, perioperative data and radiographic parameters were analyzed.

RESULTS

The mean patient age, follow-up period, operation time, and volume of surgical drainage were 68.3 ± 8.4 years, 7.6 ± 2.8 months, 188.3 ± 42.4 min, 92.5 ± 49.6 mL, respectively. There were no transfusion cases. All patients showed significant improvement in VAS and ODI postoperatively, and these were maintained for 6 months after surgery (P < 0.001). The anterior and posterior disc heights significantly increased after surgery (P < 0.001), and the cage was ideally positioned in all patients. There were no incidences of early cage subsidence or other complications.

CONCLUSIONS

BE-EFLIF using a 3D-printed porous titanium cage with large footprints is a feasible option for minimally invasive lumbar interbody fusion. This technique is expected to reduce the risk of cage subsidence and improve the fusion rate.

Effect of Lumbar Spinal Stenosis on Treatment of Osteoporosis: Comparison of Three Oral Bisphosphonate Therapies

(1) Background: Lumbar spinal stenosis (LSS) causes uncomfortable neuropathic symptoms, which can negatively affect osteoporosis. The aim of this study was to investigate the effect of LSS on bone mineral density (BMD) in patients treated with one of three oral bisphosphonates (ibandronate, alendronate and risedronate) for initially diagnosed osteoporosis. (2) Methods: We included 346 patients treated with oral bisphosphonates for three years. We compared annual BMD T-scores and BMD increases between the two groups according to symptomatic LSS. The therapeutic efficacies of the three oral bisphosphonates in each group were also evaluated. (3) Results: Annual and total increases in BMD were significantly greater in group I (osteoporosis) compared to group II (osteoporosis + LSS). The total increase in BMD for three years was significantly greater in the ibandronate and alendronate subgroups than that in the risedronate subgroup (0.49 vs. 0.45 vs. 0.25, p < 0.001). Ibandronate showed a significantly greater increase in BMD than that of risedronate in group II (0.36 vs. 0.13, p = 0.018). (4) Conclusions: Symptomatic LSS may interfere with the increase in BMD. Ibandronate and alendronate were more effective in treating osteoporosis than risedronate. In particular, ibandronate was more effective than risedronate in patients with both osteoporosis and LSS.

Learning curve for biportal endoscopic posterior cervical foraminotomy determined using the cumulative summation test

BACKGROUND

Learning curves describe the rate of performance improvements corresponding to the surgeon's caseload, followed by a plateau where limited further improvements are observed. This study aimed to determine the learning curve for biportal full-endoscopic posterior cervical foraminotomy (BE-PCF) for the unilateral cervical foraminal disc.

METHODS

The learning curve was evaluated using a learning curve cumulative summation test (LC-CUSUM). The goal for the operation time was set to 78 min, which is the mean operation time (mOT) of percutaneous full-endoscopic posterior cervical foraminotomy (PE-PCF) performed by a senior surgeon. Moreover, clinical outcomes and post-operative complications were compared between the early and late learning periods 1 year post-operatively.

RESULTS

This study enrolled the first 50 patients who underwent single-level BE-PCF, performed by a single surgeon. The LC-CUSUM signalled competency for surgery at the 20th operation, indicating that sufficient evidence was obtained to prove that the surgeon was competent. The mOT was 71.29 ± 11.69 min in BE-PCF, 71.84 ± 12.61 min in the early learning period, and 67.83 ± 10.31 min in the late learning period (p = 0.254). There was no statistical difference in clinical outcomes, visual analogue scale scores, and neck disability index between both periods (p > 0.05). Four complications were recorded throughout the whole period, with three in the early period and one in the late period (p = 0.285).

CONCLUSION

Our study shows that BE-PCF has a learning curve of 20 caseloads to achieve 90% proficiency, and it significantly reduces the operation time based on the performance of a senior surgeon proficient in PE-PCF.

Development and Validation of a Risk-Prediction Nomogram for Chronic Low Back Pain Using a National Health Examination Survey: A Cross-Sectional Study

BACKGROUND

Several prognostic factors have been reported for chronic low back pain (CLBP). However, there are no studies on the prediction of CLBP development in the general population using a risk prediction model. This cross-sectional study aimed to develop and validate a risk prediction model for CLBP development in the general population, and to create a nomogram that can help a person at risk of developing CLBP to receive appropriate counseling on risk modification.

METHODS

Data on CLBP development, demographics, socioeconomic history, and comorbid health conditions of the participants were obtained through a nationally representative health examination and survey from 2007 to 2009. Prediction models for CLBP development were derived from a health survey on a random sample of 80% of the data and validated in the remaining 20%. After developing the risk prediction model for CLBP, the model was incorporated into a nomogram.

RESULTS

Data for 17,038 participants were analyzed, including 2693 with CLBP and 14,345 without CLBP. The selected risk factors included age, sex, occupation, education level, mid-intensity physical activity, depressive symptoms, and comorbidities. This model had good predictive performance in the validation dataset (concordance statistic = 0.7569, Hosmer-Lemeshow chi-square statistic = 12.10, p = 0.278). Based on our model, the findings indicated no significant differences between the observed and predicted probabilities.

CONCLUSIONS

The risk prediction model presented by a nomogram, which is a score-based prediction system, can be incorporated into the clinical setting. Thus, our prediction model can help individuals at risk of developing CLBP to receive appropriate counseling on risk modification from primary physicians.