A novel preoperative trajectory evaluation method for L5-S1 transforaminal percutaneous endoscopic lumbar discectomy

Impact of computed tomography/magnetic resonance imaging registration on rehabilitation after percutaneous endoscopic decompression for lumbar stenosis: Retrospective study

BACKGROUND

Percutaneous endoscopic lumbar decompression (PELD) shows promise for lumbar spinal stenosis (LSS) treatment, but its use is limited by the disease's complexity and procedural challenges.

AIM

In this study, the effects of preoperative planning and intraoperative guidance with computed tomography (CT)/magnetic resonance imaging (MRI) registration techniques on PELD for LSS and postoperative rehabilitation outcomes were evaluated.

METHODS

This retrospective study was conducted with data from patients who underwent PELD for LSS between January 2021 and December 2023. Patients were assigned to preoperative CT/MRI registration and control groups. Data collected included the operative time, length of hospital stay, visual analog scale (VAS) scores for low back and leg pain, and the Japanese Orthopaedic Association (JOA) lumbar spine score. Differences between groups were assessed using Student’s t test.

RESULTS

Data from 135 patients (71 in the CT/MRI registration group, 64 in the control group) were analyzed. The operative time was significantly shorter in the CT/MRI registration group (P = 0.007). At 2 months postoperatively, both groups showed significant reductions in VAS leg and low back pain scores (all P < 0.001) and improvements in the JOA score (both P < 0.001). No complication or death occurred. Preoperatively, pain and JOA scores were similar between groups (P = 0.830, P = 0.470, and P = 0.287, respectively). At 2 months postoperatively, patients in the CT/MRI registration group reported lower leg and low back pain levels (P < 0.001 and P = 0.001, respectively) and had higher JOA scores (P = 0.004) than did patients in the control group.

CONCLUSION

Preoperative CT/MRI registration for PELD for LSS reduced the operative time and VAS pain scores at 2 months and improved JOA scores, demonstrating enhanced effectiveness and safety.

Different approaches to percutaneous endoscopic lumbar discectomy for L5/S1 lumbar disc herniation: a retrospective study

OBJECTIVE

To observe the surgical procedure and outcome of percutaneous endoscopic lumbar discectomy for L5/S1 lumbar disc herniation (LDH) by the interlaminar and transforaminal approach.

METHODS

A total of 153 patients with L5/S1 LDH who were treated using percutaneous endoscopic transforaminal discectomy (PETD, n = 84) or percutaneous endoscopic interlaminar discectomy (PEID, n = 69) from January 2016 to January 2018 were enrolled in this retrospective study. The time of puncture, operation under the endoscope, total operation and number of fluoroscopy of the two groups were compared. All groups were followed up for two years by using the Oswestry disability index (ODI) and the Visual Analogue Scale (VAS). Additionally, the incidence of complications, reoperation and postoperative low back pain were compared between the two groups.

RESULTS

There were no significant difference in general information between the two groups. Compared to the PEID group, the PETD group had a decreased operation time under the endoscope and an increased puncture time, total operation time, and the number of fluoroscopy (p < 0.05). The preoperative VAS and ODI scores of the PETD and PEID group were decreased at the last follow-up (p < 0.05). There were no difference in the preoperative or last follow-up VAS and ODI scores, as well as complications, reoperation between the two groups (p > 0.05). The incidence of postoperative low back pain in the PETD group was lower than that in the PEID group (p > 0.05).

CONCLUSIONS

The two-year clinical outcome of PETD is equal to that of PEID for L5/S1 LDH. Compared to those with PETD, the puncture time, total operation time and radiation exposure are lower with PEID, but the incidence of postoperative low back pain is higher.

Deep Learning-Based Automated Magnetic Resonance Image Segmentation of the Lumbar Structure and Its Adjacent Structures at the L4/5 Level

(1) Background: This study aims to develop a deep learning model based on a 3D Deeplab V3+ network to automatically segment multiple structures from magnetic resonance (MR) images at the L4/5 level. (2) Methods: After data preprocessing, the modified 3D Deeplab V3+ network of the deep learning model was used for the automatic segmentation of multiple structures from MR images at the L4/5 level. We performed five-fold cross-validation to evaluate the performance of the deep learning model. Subsequently, the Dice Similarity Coefficient (DSC), precision, and recall were also used to assess the deep learning model's performance. Pearson's correlation coefficient analysis and the Wilcoxon signed-rank test were employed to compare the morphometric measurements of 3D reconstruction models generated by manual and automatic segmentation. (3) Results: The deep learning model obtained an overall average DSC of 0.886, an average precision of 0.899, and an average recall of 0.881 on the test sets. Furthermore, all morphometry-related measurements of 3D reconstruction models revealed no significant difference between ground truth and automatic segmentation. Strong linear relationships and correlations were also obtained in the morphometry-related measurements of 3D reconstruction models between ground truth and automated segmentation. (4) Conclusions: We found it feasible to perform automated segmentation of multiple structures from MR images, which would facilitate lumbar surgical evaluation by establishing 3D reconstruction models at the L4/5 level.

Usefulness of Source Images of Magnetic Resonance Myelograms and Partial Laminectomy for Interlaminar Endoscopic Lumbar Discectomy at L5-S1: A Technical Note and Preliminary Clinical Results

ABSTRACT

The primary objective of this study was to assess the clinical and radiologic outcomes and introduce the technical notes from 10 patients who underwent interlaminar endoscopic lumbar discectomy (IELD) at L5-S1 using the source images of magnetic resonance (MR) myelograms and performing partial laminectomy. A biportal endoscopic system was used to perform partial laminectomy, followed by fragmentectomy and subtotal discectomy using a uniportal endoscopic system. The source images of MR myelograms were used to identify the anatomical relationship between the herniated disc material, L5 and S1 nerve roots, the thecal sac, and L5 lamina. Preoperative leg and back visual analog scale scores were greatly improved immediately and after 3 months and 6 months postoperatively. Fragmentectomy and subtotal discectomy became easier after performing a partial laminectomy in all IELD cases at L5-S1. The source images of MR myelograms and partial laminectomy is useful for IELD at L5-S1.

LEVEL OF EVIDENCE

Level IV.

Percutaneous Transforaminal Endoscopic Discectomy Versus Microendoscopic Discectomy for Lumbar Disk Herniation: Five-year Results of a Randomized Controlled Trial

STUDY DESIGN

A prospective randomized controlled study.

OBJECTIVE

To compare the efficacy and safety between percutaneous transforaminal endoscopic discectomy (PTED) and microendoscopic discectomy (MED).

SUMMARY OF BACKGROUND DATA

Two kinds of minimally invasive discectomy, PTED and MED, are now widely used for treating lumbar disk herniation (LDH). The long-term comparative results of these two techniques still remained uncertain.

MATERIALS AND METHODS

In this single-center, open-label, randomized controlled trial, patients were included if they had persistent signs and symptoms of radiculopathy with corresponding imaging-confirmed LDH and were randomly allocated to PTED or MED groups. The primary outcome was the score of Oswestry Disability Index (ODI) and the secondary outcomes included the score of Medical Outcomes Study 36-Item Short-Form Health Survey bodily pain (SF36-BP) and physical function (SF36-PF), European Quality of Life-Five Dimensions (EQ-5D), Visual Analog Scales for back pain (VAS-back) and leg pain (VAS-leg).

RESULTS

A total of 241 patients were accepted to enroll in our randomized controlled trial, of which 119 were randomly assigned to the PTED group, and the rest 122 were assigned to the MED group. A total of 194 out of 241 patients (80.5%) completed the five-year follow-up. PTED group was associated with shorter postoperative in-bed time and length of hospital stay. Both primary and secondary outcomes did not differ significantly between the two treatment groups at each follow-up time point. During the five-year follow-up, seven recurrent cases occurred in PTED and MED groups, respectively.

CONCLUSION

Over the five-year follow-up period, PTED and MED were both efficacious in the treatment of LDH. The long-term clinical outcomes and recurrent rates were comparable between the treatment groups. PTED represents a more minimally invasive technique with the advantages of rapid recovery.

Variation in spatial distance between the lumbar interlaminar window and intervertebral disc space during flexion-extension

PURPOSE

Knowledge of interlaminar space is important for undertaking percutaneous endoscopic discectomy via an interlaminar approach (PED-IL). However, dynamic changes in the lumbar interlaminar space and the spatial relationship between the interlaminar space and intervertebral disc space (IDS) are not clear. The aim of this study was to anatomically clarify the changes in interlaminar space height (ILH) and variation in distance between the two spaces during flexion-extension of the lumbar spine in vitro.

METHODS

First, we used a validated custom-made loading equipment to obtain neutral, flexion, and extension 3D models of eight lumbar specimens through 3D reconstruction software. Changes in ILH (ILH, IL-yH, IL-zH) and distances between the horizontal plane passing through the lowest edge of the lamina of the superior lumbar vertebrae and the horizontal plane passing through the lowest position of the trailing edge of the same-level IDS (DpLID) at L3/4, L4/5 and L5/S1 were examined on 3D lumbar models.

RESULTS

We found that ILH was greater at L4/5 than at L3/4 and L5/S1 in the neutral position, but the difference was not significant. In the flexion position, ILH was significantly more than that in neutral and extension positions at L3/4, L4/5, and L5/S1. There were significantly more DpLID changes from neutral to flexion than that from neutral to extension at all levels (L3/4, L4/5, L5/S1).

CONCLUSION

These findings demonstrated level-specific changes in ILH and DpLID during flexion-extension. The data may provide a better understanding of the spatial relationship between lumbar interlaminar space and IDS, and aid the development of segment-specific treatment for PED-IL.

Magnetic Resonance Neurography for Evaluation of Dorsal Root Ganglion Morphology

BACKGROUND

In this study, the morphologic characteristics and anatomic position of the dorsal root ganglion (DRG) were measured and analyzed in healthy people using magnetic resonance neurography (MRN), which provided an anatomical reference for minimally invasive spinal surgery.

METHODS

From January 2018 to December 2019, 20 healthy adult volunteers (10 male and 10 female volunteers between 20 and 65 years old) were scanned and imaged by 3.0 T magnetic resonance imaging combined with neuroimaging technology. Here, the position of the DRG was located, and the shape and size of the DRG, as well as its distance to the upper pedicle, were measured.

RESULTS

All volunteers provided satisfactory MRN scans of the L1-S1 lumbar DRG. According to the spatial position of the DRG, the morphology of the DRG can be divided into the intervertebral foramen type (81.01%), intraspinal type (16.01%), extraforaminal type (0.8%), and mixed type (2.0%).

CONCLUSIONS

The intervertebral foramen type and Intraspinal type were observed to be the main distribution forms of lumbar DRG. Due to the downward movement of lumbar segments, the position of the DRG was noted to gradually move to the spinal canal while its volume gradually increased. In addition, the distance from the upper pedicle was found to decrease gradually. MRN imaging can clearly show the shape, location, and adjacent relationship of the DRG, providing effective imaging guidance for the minimally invasive lumbar techniques.

Percutaneous endoscopic transforaminal discectomy for the treatment of L5-S1 lumbar disc herniation and the influence of iliac crest height on its clinical effects

The present study aimed to explore the clinical effects of percutaneous endoscopic transforaminal discectomy using a transforaminal endoscopic spine system (TESSYS) technique for the treatment of L5-S1 lumbar disc herniation and to analyse the influence of iliac crest height on these clinical effects. The clinical data of 76 patients with L5-S1 single-segment disc herniation treated with TESSYS at The Second Affiliated Hospital and Third Affiliated Hospital of Xi'an Jiaotong University between January and December 2016 were retrospectively analysed. Patients were divided into the following three groups according to the positional relation between the highest point of the iliac crest and the L4 and L5 pedicles in the lateral lumbar, as determined by X-ray: Group I, iliac crest height below the upper edge horizontal line of the L5 pedicle (n=42); group II, iliac crest height between the lower edge horizontal line of the L4 pedicle and the upper edge horizontal line of the L5 pedicle (n=29) and group III, iliac crest height above the lower edge horizontal line of the L4 pedicle (n=5). Changes in the postoperative visual analogue scale (VAS) pain score and Oswestry disability index (ODI) of the lower back and lower limbs were observed, and the effects were compared among the three groups. The mean operating time was 86.5±13.5 min. A single patient experienced cerebrospinal fluid leakage due to a mild tear of the dura mater during the operation, which improved after symptomatic treatment. The same operation was repeated in one patient due to the recurrence of disc herniation. In all patients, the VAS pain score and ODI of the lower back and lower limbs at 1 week and 1, 3 and 12 months following the operation were significantly lower than those before the operation (all P<0.05). Furthermore, the postoperative VAS pain score and ODI of the lower back and lower limbs were poorer in group III (L5-S1 lumbar disc herniation complicated with high iliac crest) than in groups I and II (P<0.05). These results suggested that TESSYS was effective in treating lumbar disc herniation. Whether the iliac crest is higher than the lower edge horizontal line of the L4 pedicle is suggested to be one of the factors influencing the outcome of the operation.

Gradient local anesthesia for percutaneous endoscopic interlaminar discectomy at the L5/S1 level: a feasibility study

BACKGROUND

During the process of shearing the ligamentum flavum, rotating the working channel, and manipulating the annulus fibrosis, the sinuvertebral nerve and the spinal nerve root can be irritated, inducing intolerable back and leg pain. Thus, general anesthesia is recommended and well accepted by most surgeons when performing percutaneous endoscopic lumbar discectomy (PELD) via the interlaminar approach. The aim of our study was to explore the efficacy and safety of percutaneous endoscopy interlaminar lumbar discectomy with gradient local anesthesia (LA) in patients with L5/S1 disc herniation.

METHODS

This retrospective study was conducted between December 2017 and June 2018. The study included 50 consecutive patients who met the study criteria, had single-level L5/S1 disc herniation, and underwent PELD via the interlaminar approach under gradient LA. Different concentrations of local anesthetic compound (LAC) were injected into different tissues inside and outside the ligamentum flavum to complete gradient LA. The evaluation criteria included the intraoperative satisfaction score, visual analog scale (VAS) score, Oswestry Disability Index (ODI), complications, and adverse reactions.

RESULTS

The intraoperative satisfaction score was consistently over 7, with an average score of 9.3 ± 0.7, indicating that LAC can achieve satisfactory pain control throughout the PELD operation without additional anesthesia. The postoperative VAS score and ODI were dramatically improved at each follow-up interval (P < 0.001, respectively). There was no serious complication such as dural rupture caused by puncture, dural laceration caused by manipulation under endoscopy, total spinal anesthesia, iatrogenic nerve root injury, epidural hematoma, infections, or local anesthetic-related adverse reactions. Three patients experienced transient postoperative dysesthesia of the lower limbs that gradually recovered within 24 h.

CONCLUSIONS

Gradient local anesthesia can satisfactorily and safely control intraoperative pain during the PELD via the interlaminar approach. It can not only improve intraoperative satisfaction, but also reduce local anesthesia-related adverse reactions and surgery-related complications.

Preoperative Simulation of the Trajectory for L5/S1 Percutaneous Endoscopic Transforaminal Discectomy: A Novel Approach for Decision-Making

OBJECTIVE

We simulated the trajectory for an L5/S1 percutaneous endoscopic transforaminal discectomy (PETD) to guide decision-making for the surgery approach.

METHODS

Twenty-three patients with L5/S1 lumbar disc herniation were included in the study. The patients all underwent thin-section computed tomography scans, after which data were collected for 3-dimensional reconstruction. Simulations of the trajectory for the L5/S1 PETDs were generated and the hindrance of surrounding anatomic structures was evaluated.

RESULTS

Preoperative simulation showed that 14 patients were considered suitable for lumbar PETD. Nine patients were not considered suitable for PETD surgery according to the simulation. Factors affecting the trajectory included high iliac crest in 5 patients, L5 transverse process in 3 patients, and hypertrophic L5-S1 facet joint in 1 patient.

CONCLUSIONS

Preoperative simulation of the trajectory for L5/S1 PETD was helpful in the decision-making for the surgical approach.

Deep learning-based lumbosacral reconstruction for difficulty prediction of percutaneous endoscopic transforaminal discectomy at L5/S1 level: A retrospective cohort study

BACKGROUND

Deep learning has been validated as a promising technique for automatic segmentation and rapid three-dimensional (3D) reconstruction of lumbosacral structures on CT. Simulated foraminoplasty of percutaneous endoscopic transforaminal discectomy (PETD) through the Kambin triangle may benefit viability assessment of PETD at L5/S1 level.

MATERIAL AND METHODS

Medical records and radiographic data of patients with L5/S1 lumbar disc herniation (LDH) who received a single-level PETD from March 2013 to February 2018 were retrospectively collected and analyzed. Deep learning was adopted to achieve semantic segmentation of lumbosacral structures (nerve, bone, disc) on CT, and the segmented masks on reconstructed 3D models. Two observers measured the area of the Kambin triangle on 6 selected deep learning-derived 3D (DL-3D) models and ground truth-derived 3D (GT-3D) models, and intraclass correlation coefficient (ICC) was calculated to assess the test-retest and interobserver reliability. Foraminoplasty of PETD was simulated on L5/S1 lumbosacral 3D models. Patients with extended foraminoplasty or stuck canula occurs on simulations were predicted as PETD-difficult cases (Group A). The remaining patients were regarded as PETD-normal cases (Group B). Clinical information and outcomes were compared between the two groups.

RESULTS

Deep learning-derived 3D models of lumbosacral structures (nerves, bones, and disc) from thin-layer CT were reliable. The area of the Kambin triangle was 161.27 ± 40.10 mm² on DL-3D models and 153.57 ± 32.37 mm² on GT-3D models (p = 0.206). Reliability test revealed strong test-retest reliability (ICC between 0.947 and 0.971) and interobserver reliability of multiple measurements (ICC between 0.866 and 0.961). The average operation time was 99.62 ± 17.39 min in Group A and 88.93 ± 21.87 min in Group B (P = 0.025). No significant differences in patient-reported outcomes or complications were observed between the two groups (P > 0.05).

CONCLUSION

Deep learning achieved accurate and rapid segmentations of lumbosacral structures on CT, and deep learning-based 3D reconstructions were efficacious and reliable. Foraminoplasty simulation with deep learning-based lumbosacral reconstructions may benefit surgical difficulty prediction of PETD at L5/S1 level.

Treatment of high-iliac-crest L5-S1 lumbar disc herniation via a transverse process endoscopic transforaminal approach

OBJECTIVE

To investigate the clinical efficacy of transverse process endoscopic transforaminal discectomy for the treatment of high-iliac-crest L5-S1 lumbar disc herniation.

METHODS

Seventeen patients with high-iliac-crest L5-S1 lumbar disc herniation who were treated with transforaminal endoscopy from April 2016 to January 2019 in the Department of Neurosurgery of Xuanwu Hospital were selected. The visual analog scale (VAS) and Oswestry disability index (ODI) were used to evaluate the efficacy of the procedure.

RESULTS

All of the patients successfully underwent the surgical treatment. Sixteen patients (94.1 %) completed effective follow-up for more than 12 months. The VAS was 7.8 ± 1.9, 2.9 ± 1.6, 2.3 ± 1.5 and 2.2 ± 1.6 before surgery and at one day, 3 months, and the last follow-up after surgery, respectively. The ODI scores were 52.8 ± 15.2 and 16.9 ± 9.7 before surgery and 3 months after surgery, respectively, both of which were lower than before surgery (both P < 0.01).

EFFICACY EVALUATION

An excellent outcome was achieved in 13 (81.3 %) patients, a good outcome in 1 patient (6.3 %), an acceptable outcome in 1 patient (6.3 %), and a poor outcome in 1 patient (6.3 %).

CONCLUSIONS

The transverse process endoscopic transforaminal discectomy is a safe and effective surgical method for the treatment of high-iliac-crest L5-S1 lumbar disc herniation.

Does anxiety influence the prognosis of percutaneous transforaminal endoscopic discectomy in the treatment of lumbar disc herniation? A preliminary propensity score matching analysis

PURPOSE

Previous reports revealed a correlation between psychological problems and spinal surgery. There is a lack of knowledge on the effect of anxiety on the percutaneous transforaminal endoscopic discectomy (PTED) outcome at the two year follow-up. The purpose of this study is to investigate changes in anxiety after PTED among patients with lumbar disc herniation (LDH), to compare the effect of anxiety on the prognosis using propensity score matching analysis, and to identify the related parameters of anxiety.

METHODS

A total of 145 patients with LDH requiring PTED surgery were included. Twenty-six LDH patients with anxiety were matched with 26 control patients utilizing propensity score matching analysis. The demographic and peri-operative data were collected and analyzed. A correlation analysis was utilized.

RESULTS

Both groups achieved significant improvements in visual analogue scale (VAS) scores for pain, Japanese Orthopedic Association (JOA) scores for neurological deficit, and 36-item Short-Form Health Survey (SF-36) scores and Oswestry Disability Index (ODI) scores for quality of life. A statistical difference was detected between the pre-operative and the post-operative Zung Self-Rating Anxiety Scale scores in the anxiety cohort. However, the difference between the anxiety group and the control group was statistically significant in the aforementioned parameters. The VAS, JOA, ODI and the SF-36 scores, and the disease duration were associated with pre-operative anxiety.

CONCLUSION

PTED may provide significant improvements in clinical outcomes and symptoms of anxiety. A negative impact on the patient's prognosis may be caused by the presence of anxiety. Pain severity, neurological deficit, disease duration, and quality of life were associated with anxiety.

Using Visual Trepan to Treat Single Segment Ossification of the Ligamentum Flavum Under Endoscopy

This article describes the trepan technique for treating single segment ossification of the ligamentum flavum (OLF) using an endoscope. OLF is the most common cause of thoracic spinal stenosis. The most common surgical procedures involve semi‐lamina or full‐lamina resection and decompression. However, considering the anatomical structure of the thoracic spinal canal and the combination of OLF, traditional surgery has higher risks, more complications, and greater technical requirements. In the past ten years, with the development of endoscopic technology, spinal endoscopy has been increasingly applied for the treatment of intervertebral disc herniation and spinal canal stenosis. The present study demonstrated the effectiveness of visual trepan decompression under spinal endoscopy used for patients with single segment OLF. This surgical procedure had many advantages, including a shorter operation time, minimal trauma, less expenditure, and better functional recovery over the conventional open surgery.

The Effect of Using Visual Trepan to Treat Single-Segment Ossification of Ligamentum Flavum Under the Endoscope

OBJECTIVES

To evaluate the surgical outcome of using a trepan to treat single-segment ossification of ligamentum flavum under endoscopy and the clinical value of the new surgical treatment.

MATERIALS AND METHODS

Patients who underwent surgery for single-segment ossification of ligamentum flavum from January 2015 to June 2018 were included in a retrospective analysis. Endoscopic visual trepan decompression was performed in 26 patients and posterior spinal canal resection and decompression was performed in 11 patients. Japanese Orthopaedic Association scores, Japanese Orthopaedic Association improvement rate, and visual analog scale scores of both groups were recorded during follow-up. Computed tomography was used to evaluate patients' residual area ratio of the vertebral canal. Operative time, length of stay, amount of bleeding, and hospital cost in both groups were recorded.

RESULTS

Average follow-up time was 8.9 ± 2.7 months. Average operative time was 100.6 ± 35.0 minutes in the experimental group and 140.5 ± 28.3 minutes in the control group. At the final follow-up, the average improvement rate of Japanese Orthopaedic Association score was 78.3% in the experimental group and 84.2% in the control group. The average residual area ratio of the vertebral canal, which was <50% before the operation in both groups, recovered to 100% in both groups after the operation. Visual analog scale score of all patients was significantly (P < 0.05) reduced at the final follow-up.

CONCLUSIONS

The visual trepan technique using a spinal endoscope can be used to treat single-segment ossification of ligamentum flavum. Advantages include less trauma, faster recovery, and lower cost. However, more cases and long-term follow-up are required to further evaluate the clinical effectiveness and safety of this surgical method.

A Cost-utility Analysis of Percutaneous Endoscopic Lumbar Discectomy for L5-S1 Lumbar Disc Herniation: Transforaminal versus Interlaminar

STUDY DESIGN

A cost-utility analysis (CUA).

OBJECTIVE

The aim of this study was to evaluate the cost-effectiveness of percutaneous endoscopic transforaminal discectomy (PETD) and percutaneous endoscopic interlaminar discectomy (PEID) techniques for the treatment of L5-S1 lumbar disc herniation (LDH).

SUMMARY OF BACKGROUND DATA

The annual cost of treatment for lumbar disc herniation is staggering. As the two major approaches of percutaneous endoscopic lumbar discectomy (PELD): percutaneous endoscopic transforaminal discectomy (PETD) and percutaneous endoscopic interlaminar discectomy (PEID) have gained recognition for the treatment of L5-S1 lumbar disc herniation (LDH) and showed similar clinical outcome. ost-utility analysis (CUA) can help clinicians make appropriate decisions about optimal health care for L5-S1 LDH.

METHODS

Fifty and 25 patients were included in the PETD and PEID groups of the study. Patients' basic characteristics, health care costs, and clinical outcome of PETD and PEID group were collected and analyzed. Quality-adjusted life-years (QALYs) were calculated and validated by EuroQol five-dimensional (EQ-5D) questionnaire. Cost-effectiveness was determined by the incremental cost per QALY gained.

RESULTS

The mean total cost of the PETD group was $5275.58 ± 292.98 and the PEID group was $5494.45 ± 749.24. No significant differences were observed in hospitalization expenses, laboratory and radiographic evaluations expenses, surgical expenses, and drug costs. Surgical equipment and materials costs, and anesthesia expense in the PEID group were significantly higher than in the PETD group (P < 0.001). Clinical outcomes, including Oswestry Disability Index (ODI), Visual Analogue Scale (VAS) scores, and Japanese Orthopaedic Association (JOA), also showed no significant differences between the two groups. The cost-effectiveness ratio of PETD and PEID were $6816.05 ± 717.90/QALY and $7073.30 ± 1081.44/QALY, respectively. The incremental cost-effectiveness ratios (ICERs) of PEID over PETD was $21887.00/QALY.

CONCLUSION

Observed costs per QALY gained for L5-S1 LDH with PETD or PEID were similar for patients, demonstrating that the two different approaches of PELD are equally cost-effective and valuable interventions.

LEVEL OF EVIDENCE

5.

Radiation Exposure and Operation Time in Percutaneous Endoscopic Lumbar Discectomy Using Fluoroscopy-Based Navigation System

OBJECTIVE

This study evaluated radiation exposure and operation time of percutaneous endoscopic lumbar discectomy (PELD) by using a fluoroscopy-based navigation system for access and localization.

METHODS

Eighty-six PELDs performed by a single surgeon were retrospectively analyzed. Patients were separated into 2 groups: group A (using a three-dimensional [3D]-printed navigation instrument and fluoroscopy-based navigation system) and group B (with conventional fluoroscopy and standard instrumentation). The operation, fluoroscopy, and total access time were collected, as well as fluoroscopy and access times.

RESULTS

The operative time for group A was 59 minutes (standard deviation [SD], 6 minutes) and 106 minutes (SD, 15 minutes) in group B (P < 0.001). In group A, fluoroscopy was used an average of 5 times (SD, 0.7) and 29 times (SD, 8) in group B (P < 0.001). The fluoroscopy time was 9 minutes (SD, 2 minutes) in group A and 40 minutes (SD, 8 minutes) in group B (P < 0.001). The number of access attempts was 1.3 (SD, 0.5) in group A and 8 (SD, 2 times) in group B (P < 0.001). The total access time was 11 minutes (SD, 2 minutes) in group A and 28 minutes (SD, 5 minutes) in group B (P < 0.001).

CONCLUSIONS

PELD using the fluoroscopy-based navigation system showed lower operative, fluoroscopy, and access time compared with conventional techniques. In addition, fewer fluoroscopy images and access attempts were made in the navigation group. These data suggest that this novel technique reduces fluoroscopy and operation time and may reduce risks of repeated surgical access attempts.

Comparison of Transforaminal Percutaneous Endoscopic Lumbar Discectomy with and without Foraminoplasty for Lumbar Disc Herniation: A 2-Year Follow-Up

Background

Both transforaminal percutaneous endoscopic lumbar discectomy with foraminoplasty (TF PELF) and transforaminal percutaneous endoscopic lumbar discectomy without foraminoplasty (TF PELD) were developed for lumbar disc herniation (LDH) patients. However, the safety and effectiveness between the TF PELF and TF PELD have not been investigated.

Methods

Of the included 140 LDH patients, 62 patients received TF PELF (PELF group) and 78 patients received TF PELD (PELD group). The operation time, the duration of staying at the hospital, and complication incidences were recorded. All patients were followed up for 2 years, where low back and leg visual analogue scale (VAS) pain ratings and Oswestry Disability Index (ODI) were compared between the 2 groups before and after surgery. Modified Macnab criterion was estimated for all patients at postoperative 2 years.

Results

There were no significant difference of the operation time, number of days staying at the hospital, and the incidence of complications between the 2 groups (P > 0.05). Two cases in the PELF group and 1 case in the PELD group received a second surgery due to unrelieved symptoms postoperatively. Low back and leg VAS and ODI scores decreased in both groups after operation (P < 0.01), respectively, but were not significant between the 2 groups over time (P > 0.05). Six patients in the PELF group and 3 patients in the PELD group did not continue the follow-up; thus, only 131 patients completed Macnab evaluation. The satisfactory rate was reported as 80.4% in the PELF group and 90.7% in the PELD group (P > 0.05).

Conclusions

This study suggested that the safety and effectiveness of TF PELF are comparable to TF PELD for LDH patients.

Concentric Stereotactic Technique of Percutaneous Endoscopic Transforaminal Discectomy and Radiation Exposure to Surgeons

OBJECTIVE

In percutaneous endoscopic transforaminal discectomy (PETD), surgeons are exposed to intraoperative radiographic radiation over a long-term career, which may be correlated with high risk of iatrogenic radiation hazards. The purpose of this prospective cohort study was to assess the impact of concentric stereotactic technique on radiation exposure to surgeons in PETD.

METHODS

Patients who underwent conventional PETD were regarded as group A, whereas those undergoing PETD with concentric stereotactic technique were considered as group B. The primary outcomes were cumulative radiation dose to the surgeon's eye, thyroid gland, and breast.

RESULTS

A total of 34 patients were treated in group A and 30 patients were treated in group B. The cumulative radiation dose of the eye per operation was 0.017 (0.58/34) mSv in group A and 0.010 (0.31/30) mSv in group B, which meant a reduction of 41.18%. The cumulative radiation dose of the thyroid gland per operation was 0.018 (0.60/34) mSv in group A and 0.011 (0.33/30) mSv in group B, which meant a reduction of 38.89%. The cumulative radiation dose of the chest per operation was 0.039 (1.33/34) mSv in group A and 0.023 (0.70/30) mSv in group B, which meant a reduction of 41.03%. There were no significant differences in hospital stay, visual analog scale score of waist and leg pain, Oswestry Disability Index score, MacNab satisfaction, and complications between the 2 groups (P > 0.05).

CONCLUSIONS

The concentric stereotactic technique can effectively reduce radiation exposure to surgeons by about 40%.

Isocentric Navigation for the Training of Percutaneous Endoscopic Transforaminal Discectomy: A Feasibility Study

Background

Percutaneous endoscopic transforaminal discectomy (PETD) is usually chosen for lumbar disc herniation due to its obvious advantages such as small incision and absence of nerve or muscular traction. However, learning PETD is a great challenge for inexperienced surgeons.

Objective

The study aimed to investigate whether isocentric navigation would be beneficial in PETD training.

Methods

A total of 117 inexperienced surgeons were trained with PETD at L2/3, L3/4, L4/5, and L5/S1 on the cadavers without (Group A n=58) or with (Group B n=59) isocentric navigation. Puncture times, fluoroscopy times, exposure time, and radiation dose were recorded and analyzed. Questionnaires were conducted before and after the training program.

Result

Isocentric navigation could improve young surgeons' satisfaction with the training program and decrease the puncture times, fluoroscopy times, exposure time, and radiation dose significantly (P<0.001).

Conclusion

Isocentric navigation contributes to the training of PETD and may improve its standardization, homogenization, and generalization.