Comparison of different concentrations of ropivacaine in epidural anesthesia for percutaneous transforaminal endoscopic discectomy: a randomized controlled trial.

BACKGROUND: This study investigated the optimal concentration of ropivacaine epidural anesthesia for clinical use in percutaneous transforaminal endoscopic discectomy (PTED) by comparing the effects of different concentrations. METHODS: Seventy patients scheduled for their first PTED procedure were enrolled in this randomized controlled trial. Patients were randomized to receive ropivacaine at varying concentrations (0.3% or 0.4%). Primary outcome measures included the numeric rating scale (NRS) and hip extension level (HEL). Secondary outcome measures included intraoperative fentanyl dosage and postoperative complications. RESULTS: One patient withdrew due to severe postoperative complications. The remaining 69 patients were allocated to the 0.3% (n = 34) and 0.4% (n = 35) groups, respectively. Baseline characteristics showed no significant differences between the two groups (P > 0.05). The NRS score was significantly lower in the 0.4% group than in the 0.3% group (P < 0.01), whereas the HEL score was significantly higher (P < 0.001). The average fentanyl dose in the 0.4% group was significantly lower than that in the 0.3% group (P < 0.01). Postoperative complications occurred in five and two patients in the 0.3% and 0.4% groups, respectively. CONCLUSION: Although 0.4% ropivacaine (20 mL) impacts muscle strength, it does not impede PTED surgery. Given its effective analgesic properties and few postoperative complications, 0.4% ropivacaine can be considered a preferred dose for PTED. TRIAL REGISTRATION: This study was registered with the Chinese Clinical Trials Registry (Registration number: ChiCTR2200060364; Registration Date: 29/5/2022) and on chictr.org.cn ( https://www.chictr.org.cn/showproj.html?proj=171002 ).

Analysis of the clinical efficacy of visualization of percutaneous endoscopic lumbar discectomy combined with annulus fibrosus suture in lumbar disc herniation.

The objective of this study is to compare the clinical effectiveness of visualization of percutaneous endoscopic lumbar discectomy (VPELD) combined with annulus fibrosus suture technique and simple percutaneous endoscopic lumbar discectomy (PELD) technique in the treatment of lumbar disc herniation. A retrospective analysis was conducted on 106 cases of lumbar disc herniation treated with foraminoscopic technique at our hospital from January 2020 to February 2022. Among them, 33 cases were treated with VPELD combined with annulus fibrosus suture in group A, and 73 cases were treated with PELD in group B. The preoperative and postoperative visual analogue scale (VAS), functional index (Oswestry Disability Index, ODI), healing of the annulus fibrosus, intervertebral space height, and postoperative recurrence were recorded and compared between the two groups. All patients underwent preoperative and postoperative MRI examinations, and the average follow-up period was 12 ± 2 months. Both groups showed significant improvements in postoperative VAS and ODI scores compared to the preoperative scores (P < 0.05), with no statistically significant difference between the groups during the same period (P > 0.05). There was no significant decrease in intervertebral space between the two groups after surgery (P > 0.05). Group A showed significantly lower postoperative recurrence rate and better annulus fibrosus healing compared to group B (P < 0.05). The VPELD combined with annulus fibrosus suture technique is a safe, feasible, and effective procedure for the treatment of lumbar disc herniation. When the indications are strictly adhered to, this technique can effectively reduce the postoperative recurrence rate and reoperation rate. It offers satisfactory clinical efficacy and can be considered as an alternative treatment option for eligible patients.

Vascular loops mimicking herniated lumbar discs: fair warning.

The authors report their experience with twenty-one consecutive patients who presented with symptoms and imaging characteristics of a herniated lumbar disc; of whom, at the time of surgery had a vascular loop instead. The procedure was performed on 14 women and seven men with a mean age of 39 years. Clinical complaints included lumbar aching with one limb overt radiculopathy in all patients; with additional sphincter dysfunction in two cases. Symptoms had developed within a mean period of three months. In all patients, the disc was exposed through an L5-S1 (n = 10); L4-L5 (n = 5) and L3-L4 (n = 6) open minimal laminotomy. In 16 patients, rather than a herniated disc they had a lumbar epidural varix, while an arterio-venous fistula was found in the remaining five cases. In all cases, the vascular disorder was resected and its subjacent disc was left intact. One patient had a postoperative blood transfusion. While the radiculopathy dysfunction improved in all patients, four patients reported lasting lumbar pain following surgery. The postoperative imaging confirmed the resolution of the vascular anomaly and an intact disc. The mean length of the follow-up period was 47 months. Either epidural varix or arterio-venous fistula in the lumbar area may mimic a herniated disc on imaging studies. With the usual technique they can be operated safely. Resection of the anomaly can be sufficient for alleviating radiculopathy symptoms.

Prognostic factors for residual symptoms following percutaneous endoscopic lumbar discectomy.

To explore the risk factors for residual symptoms following percutaneous endoscopic lumbar discectomy (PELD). A retrospective case-controlled study. From January 2015 to December 2020, consecutive patients who underwent PELD for lumbar disc herniation (LDH) in our department were retrospectively studied. All the patients were followed-up at least two years. Residual symptoms were analyzed for association with baseline data, clinical feature, physical examination, and radiographic characteristics, which were used to detected the risk factors. A total of 339 patients were included in this study, with a mean follow-up of 28.7 ± 3.6 months. Of the enrolled patients, 90 (26.5%) patients experienced residual low back pain (LBP), and 76 (22.4%) patients experienced leg numbness (LN). Multivariate logistic regression analysis revealed that intervertebral disc calcification on CT scans (odd ratio, 0.480; 95% confidence interval: 0.247 ~ 0.932; P < 0.05) was independent risk factor for postoperative residual LBP with odd ratio and longer symptom duration was risk factor for postoperative residual LN (odd ratio, 2.231; 95% confidence interval:1.066 ~ 4.671; P < 0.05). Residual symptoms following transforaminal endoscopic surgery are quite prevalent. Intervertebral disc calcification is a protective factor for residual low back pain, and a longer symptom duration is a risk factor for residual leg numbness.

Nerve root retraction time during lumbar endoscopic discectomy: association with new onset radiculitis, a post-operative neurologic complication.

PURPOSE: To evaluate the relationship between nerve root retraction time, post-operative radiculitis and patient reported outcomes. METHODS: Patients who underwent single- or multi-level lumbar discectomy between 2020 and 2022 for lumbar disk herniations were prospectively followed with pre-operative, interoperative and post-operative variables including radiculitis and patient reported outcomes including VAS, ODI and CAT domains Pain interference, Pain intensity and Physical function. Intraoperative nerve root retraction time was recorded. Paired sample two-tailed t-test and multivariate regression were utilized with p < 0.05 being significant. RESULTS: A total of 157 patients who underwent single- or multi-level endoscopic lumbar discectomy. Average patient age was 44 years, and 64% were male patients. Nerve retraction time ranged from 4 to 15 min. Eighteen percent reported new radiculitis at 2-weeks post-operatively. In patients with new-onset radiculitis 79.2% reported significantly worse VAS leg at 2 weeks post-operative (4.2 vs. 8.3, p < 0.001) compared to 12.5% who had improved VAS leg (9.3 vs. 7, p = 0.1181). Patients with radiculitis and worse VAS scores had substantially longer nerve retraction time (13.8 ± 7.5 min) than patients with improved VAS leg (6.7 ± 1.2 min). At 6 months, patients with longer nerve retraction time had no significant improvement in the ODI or CAT compared to the baseline. CONCLUSIONS: This is the first study in discectomy literature to show that new onset radiculitis and poorer outcomes in VAS leg correlate with longer nerve retraction time at early and later time points.

Return to sports following discectomy: does a consensus exist?

INTRODUCTION: In the USA, lumbar discectomy is one of the most commonly performed spinal procedures. As certain sports are considered to be major risk factors for disc herniation, the question remains as to when highly active patients should return to their previous level of activity. This study aimed to analyze spine surgeons' opinions on when patients may return to activities following discectomy as well as their underlying rationale for their decision. METHODS: A questionnaire was designed by five different fellowship-trained spine surgeons for the 168 members of the Spine Society of Australia. Questions on the surgeons experience, decision making, preferred surgical technique, the postoperative rehabilitation and the response to patient expectations were included. RESULTS: In total, 83.9% of surgeons discuss the postoperative level of activity with their patients. Sport is considered as an important contributor for good functional outcome by 71.0% of surgeons. Surgeons recommend avoiding, often permanently, weightlifting (35.7%) of the time, rugby (21.4%), horseback riding (17.9%) as well as martial arts (14.3%) postoperatively even with previous training. The return to high levels of activity is considered as a major risk factor for disc herniation recurrence by 25.8% of surgeons. Return to high level of activity is typically recommended after 3 months by 48.4% of surgeons. CONCLUSION: So far no consensus on the rehabilitation protocol and return to level of activity exists. Recommendations depend on personal experience as well as the individuals' training, and typically, a period of avoidance of sport for up to 3 months is recommended. LEVEL OF EVIDENCE: Level III, therapeutic and prognostic study.

Percutaneous endoscopic transforaminal discectomy and unilateral biportal endoscopic discectomy for lumbar disc herniation: a comparative analysis of learning curves.

OBJECTIVE: The purpose of this study was to investigate the learning curve of percutaneous endoscopic transforaminal discectomy (PETD) and interlaminar unilateral biportal endoscopic discectomy (UBED) in the treatment of lumbar disc herniation (LDH). METHODS: Between 2018 and 2023, 120 consecutive patients with lumbar disc herniation (LDH) treated by endoscopic lumbar discectomy were retrospectively included. The PETD group comprised 87 cases, and the UBED group comprised 33 cases. Cumulative sum analysis was used to evaluate the learning curve, with the occurrence of complications or unresolved symptoms defined as surgical failure, and variables of different phases of the learning curve being compared. RESULTS: The learning curve analysis identified the cutoff point at 40 cases in the PETD group and 15 cases in the UBED group. In the mastery phase, both PETD and UBED demonstrated a significant reduction in operation times (approximately 38 min for PTED and 49 min for UBED). In both PETD and UBED groups, the surgical failure rates during the learning and mastery phases showed no statistically significant differences. The visual analogue scale at the last follow-up was significantly lower than before surgery in both the PETD and UBED groups. CONCLUSION: PETD and UBED surgery are effective in the treatment of LDH with a low incidence of complications. However, achieving mastery in PETD necessitates a learning curve of 40 cases, while UBED requires a minimum of 15 cases to reach proficiency.

Surgical techniques and perioperative surgical outcomes after discectomy for calcified lumbar disc herniation: a review and meta-analysis.

INTRODUCTION: Calcified lumbar disc herniation (CLDH) poses surgical challenges due to longstanding disease and adherence of herniated disc to the surrounding neural structures. The data regarding outcomes after surgery for CLDH are limited. This review was conducted to analyse the surgical techniques, perioperative findings and the postoperative clinical outcomes after surgery for CLDH. METHODS: PRISMA guidelines were followed whilst conducting this systematic review and meta-analysis. The literature review was conducted on 3 databases (PubMed, EMBASE, and CINAHL). After thorough screening of all search results, 9 studies were shortlisted from which data were extracted and statistical analysis was done. Pooled analysis was done to ascertain the perioperative and postoperative outcomes after surgery for CLDH. Additional comparative analysis was done compared to CLDH with non-calcified lumbar disc herniation (NCLDH) cases. RESULTS: We included 9 studies published between 2016 and 2022 in our review, 8 of these were retrospective. A total of 356 cases of CLDH were evaluated in these studies with a male preponderance (56.4%). Mean operative time was significantly lower in NCLDH cases compared to CLDH cases. The mean estimated blood loss showed a negative correlation with the percentage of males. Satisfactory clinical outcomes were observed in majority of patients. The risk of bias of the included studies was moderate to high. CONCLUSION: Surgical difficulties in CLDH cases leads to increase in operative time compared to NCLDH. Good clinical outcomes can be obtained with careful planning; the focus of surgery should be on decompression of the neural structures rather than disc removal.

The long-term outcome of revision microdiscectomy for recurrent sciatica.

PURPOSE: To study the long-term outcome of revision microdiscectomy after classic microdiscectomy for lumbosacral radicular syndrome (LSRS). METHODS: Eighty-eight of 216 patients (41%) who underwent a revision microdiscectomy between 2007 and 2010 for MRI disc-related LSRS participated in this study. Questionnaires included visual analogue scores (VAS) for leg pain, RDQ, OLBD, RAND-36, and seven-point Likert scores for recovery, leg pain, and back pain. Any further lumbar re-revision operation(s) were recorded. RESULTS: Mean (SD) age was 59.8 (12.8), and median [IQR] time of follow-up was 10.0 years [9.0-11.0]. A favourable general perceived recovery was reported by 35 patients (40%). A favourable outcome with respect to perceived leg pain was present in 39 patients (45%), and 35 patients (41%) reported a favourable outcome concerning back pain. The median VAS for leg and back pain was worse in the unfavourable group (48.0/100 mm (IQR 16.0-71.0) vs. 3.0/100 mm (IQR 2.0-5.0) and 56.0/100 mm (IQR 27.0-74.0) vs. 4.0/100 mm (IQR 2.0-17.0), respectively; both p < 0.001). Re-revision operation occurred in 31 (35%) patients (24% same level same side); there was no significant difference in the rate of favourable outcome between patients with or without a re-revision operation. CONCLUSION: The long-term results after revision microdiscectomy for LSRS show an unfavourable outcome in the majority of patients and a high risk of re-revision microdiscectomy, with similar results. Based on also the disappointing results of alternative treatments, revision microdiscectomy for recurrent LSRS seems to still be a valid treatment. The results of our study may be useful to counsel patients in making appropriate treatment choices.

Minimally invasive far lateral tubular microdiscectomy: surgical technique and case series of 176 patients.

BACKGROUND: Far lateral (extraforaminal) disc herniations comprise approximately 10% of symptomatic lumbar disc herniations. They represent operative challenges due to accessibility and surgical unfamiliarity. Surgical strategies in the past have included open discectomy and posterior lumbar interbody fusion. Tubular microdiscectomies have gained traction due to their minimally invasive advantages, including reduced morbidity, pain and length of hospital stay. METHODS: We report our retrospective single institution consecutive case series of tubular far lateral microdiscectomies. One hundred and seventy-six patients were operated on over an eight-year period. Clinical outcomes were assessed after institutional ethics approval. We additionally describe our surgical technique with an illustrative video case. RESULTS: Over a mean follow-up of 21 weeks, 77% of patients had good or excellent clinical outcomes according to the MacNab criteria. 12% of patients underwent reoperation at the index level for symptom recurrence or persistence. Mean length of hospital stay was 1.3 days. There was a 1% rate of both postoperative haematoma and infection. Mean operation duration was 86 minutes. CONCLUSION: This case series represents the largest currently reported in the literature. Minimally invasive microdiscectomies performed through tubes allow for precise localisation, reduced tissue disruption and favourable clinical outcomes. Our results appear consistent with a review of the literature, demonstrating the safety and efficacy of this approach.

Postoperative recovery scores and pain management: a comparison of modified thoracolumbar interfascial plane block and quadratus lumborum block for lumbar disc herniation.

PURPOSE: In this prospective, randomized study, we aimed to compare the global recovery scores and postoperative pain management between US-guided mTLIP block versus QLB after lumbar spine surgery. METHODS: 60 patients with ASA score I-II planned for microendoscopic discectomy under general anesthesia were included. We allocated the patients into two groups: the QLB group (n = 30) or the mTLIP group (n = 30). QLB and mTLIP was performed with 30 ml 0.25% bupivacaine in the groups. Paracetamol 1 g IV 3 × 1 was ordered to the patients at the postoperative period. If the NRS score was ≥ 4, 1 mg/kg tramadol IV was administered as rescue analgesia. RESULTS: There was a significant between-group difference in the mean global QoR-40 scores 24 h postsurgery. Both the static and dynamic NRS scores were significantly lower in the postoperative 1-16 h period in the mTLIP group. There was no significant between-group difference in the NRS scores 24 h postsurgery. There was no significant between-group difference in postoperative rescue analgesia consumption. However, the need for rescue analgesia was lower in the postoperative first 5 h in the mTLIP group, and survival probability was higher in the mTLIP group according to Kaplan-Meier survival analysis. There was no significant difference between the groups in the rate of adverse events. CONCLUSION: mTLIP provided superior analgesia compared to posterior QLB. The QoR-40 scores in the mTLIP group were higher than those in the QLB group.

Kinematic analysis of chewing and swallowing function after cervical spine surgery.

PURPOSE: Although movement of the hyoid bone is different for masticatory swallowing and liquid swallowing in normal subjects, it has not been studied after cervical spine surgery. Therefore, we analyzed the swallowing dynamics of masticatory swallowing in anterior cervical spine disease surgery using foods that require chewing close to actual meals. METHODS: A day before and one week after the surgery, a videofluoroscopic swallow study (VFSS) was performed, and the distance of hyoid bone movement in the anterior and superior directions, amount of opening of the upper esophageal sphincter (UES), time of passage through the pharynx, number of swallows, and amount of pharyngeal residual were measured on the VFSS images during a masticatory swallow of corn flakes. The swallowing function was evaluated by DSS (dysphagia severity scale) and FOIS (functional oral intake scale). Imaging software was used for the measurements. RESULTS: Postoperative hyoid movement during masticatory swallowing was not significantly different for anterior movement but significantly limited in upward movement (p = 0.002); UES opening volume was significantly decreased (p < 0.001), and bolus residue was significantly worse (p < 0.001), compared to preoperative. The pharyngeal transit time was not significantly different; the number of swallows increased (p < 0.001), along with DSS (p < 0.001) and FOIS (p < 0.001), with significant differences before and after surgery, indicating worsened swallowing function. CONCLUSIONS: Swallowing function worsened in masticatory swallowing after surgery for cervical spine disease, mainly due to the restriction of upward movement of the hyoid bone and the resulting increase in pharyngeal residuals after swallowing.

Predictors of failure after primary anterior cervical discectomy and fusion for subaxial traumatic spine injuries.

INTRODUCTION: Traumatic subaxial fractures account for more than half of all cervical spine injuries. The optimal surgical approach is a matter of debate and may include anterior, posterior or a combined anteroposterior (360º) approach. Analyzing a cohort of patients initially treated with anterior cervical discectomy and fusion (ACDF) for traumatic subaxial injuries, the study aimed to identify predictors for treatment failure and the subsequent need for supplementary posterior fusion (PF). METHODS: A retrospective, single center, consecutive cohort study of all adult patients undergoing primary ACDF for traumatic subaxial cervical spine fractures between 2006 and 2018 was undertaken and 341 patients were included. Baseline clinical and radiological data for all included patients were analyzed and 11 cases of supplementary posterior fixation were identified. RESULTS: Patients were operated at a median of 2.0 days from the trauma, undergoing 1-level (78%), 2-levels (16%) and ≥ 3-levels (6.2%) ACDF. A delayed supplementary PF was performed in 11 cases, due to ACDF failure. On univariable regression analysis, older age (p = 0.017), shorter stature (p = 0.031), posterior longitudinal ligament (PLL) injury (p = 0.004), injury to ligamentum flavum (p = 0.005), bilateral facet joint dislocation (p < 0.001) and traumatic cervical spondylolisthesis (p = 0.003) predicted ACDF failure. On the multivariable regression model, older age (p = 0.015), PLL injury (p = 0.048), and bilateral facet joint dislocation (p = 0.010) remained as independent predictors of ACDF failure. CONCLUSIONS: ACDF is safe and effective for the treatment of subaxial cervical spine fractures. High age, bilateral facet joint dislocation and traumatic PLL disruption are independent predictors of failure. We suggest increased vigilance regarding these cases.

Two-step osteotomy/discectomy through cannulated screw (TOCS) technique for en bloc resection of spine tumor: surgical technique and preliminary results.

PURPOSE: We have developed a novel technique for osteotomy/discectomy during en bloc resection of spine tumors named two-step osteotomy/discectomy through cannulated screw (TOCS). This study aims at describing the procedure of TOCS technique and assessing its efficiency and safety. METHODS: We retrospectively reviewed fourteen patients who underwent en bloc resection for spine tumors using TOCS technique in our center between August 2018 and September 2022. The technique was based on a specially designed "slotted" cannulated screw which was a cannulated screw with a longitudinal slot to provide the accessibility of T-saw. During osteotomy/discectomy, the "slotted" cannulated screw was inserted obliquely along the plane between the dura and the posterior wall of spine in light of the planned osteotomy/discectomy plane under routine fluoroscopic imaging guidance. The T-saw was introduced through the screw, and the osteotomy/discectomy was performed sequentially in two steps under the guidance of the screw by turning the slot away and toward the dura. The intra-/perioperative complication, neurological function (determined by Frankel grading), surgical margin (determined by a pathologist using AJCC R system), follow-up details were documented. RESULTS: The mean duration of surgery was 599.3 (360-890) min with a mean volume of intra-operative hemorrhage of 2021.4 (800-5000) mL. The intra-/perioperative complications were found in four patients (28.6%). R0 and R1 resections were achieved in nine and five patients, respectively. There was no R2 resection. After a mean follow-up period of 30.6 (10-67) months, all patients were alive except one patient died ten months after surgery due to unrelated cause. No recurrence and implant failure were found. Thirteen patients (92.9%) exhibited completely normal neurological function same as their preoperative neurological status. CONCLUSION: Using TOCS technique can facilitate a precise, complete and safe osteotomy/discectomy procedure during en bloc resection for spine tumor without the aid of intra-operative navigation.

Unilateral biportal endoscopic discectomy versus microdiscectomy for lumbar disc herniation: a systematic review and meta-analysis.

PURPOSE: This study aimed to compare unilateral biportal endoscopic discectomy (UBED) with microdiscectomy (MD) for treating lumbar disk herniation (LDH). METHODS: A comprehensive literature search was conducted in the Embase, PubMed, Cochrane Library, CNKI, and Web of Science databases from database inception to April 2023 to identify studies comparing UBED and MD for treating LDH. This study evaluated the visual analog scale (VAS) score, Oswestry disability index (ODI), Macnab scores, operation time, estimated blood loss, hospital stay, and complications, estimated blood loss, visual analog scale (VAS) score, Oswestry disability index (ODI), and Macnab scores at various pre- and post-surgery stages. The meta-analysis was performed using RevMan 5.4 software. RESULTS: The meta-analysis included 9 distinct studies with a total of 1001 patients. The VAS scores for low back pain showed no significant differences between the groups at postoperative 1-3 months (P = 0.09) and final follow-up (P = 0.13); however, the UBED group had lower VAS scores at postoperative 1-3 days (P = 0.02). There were no significant differences in leg pain VAS scores at baseline (P = 0.05), postoperative 1-3 days (P = 0.24), postoperative 1-3 months (P = 0.78), or at the final follow-up (P = 0.43). ODI comparisons revealed no significant differences preoperatively (P = 0.83), at postoperative 1 week (P = 0.47), or postoperative 1-3 months (P = 0.13), and the UBED group demonstrated better ODI at the final follow-up (P = 0.03). The UBED group also exhibited a shorter mean operative time (P = 0.03), significantly shorter hospital stay (P < 0.00001), and less estimated blood loss (P = 0.0002). Complications and modified MacNab scores showed no significant differences between the groups (P = 0.56 and P = 0.05, respectively). CONCLUSION: The evidence revealed no significant differences in efficacy between UBED and MD for LDH treatment. However, UBED may offer potential benefits such as shorter hospital stays, lower estimated blood loss, and comparable complication rates.

Transforaminal endoscopic lumbar discectomy using a 45° puncture angle and foraminotomy versus traditional THESYS for L5/S1 lumbar disc herniation: a prospective randomized controlled trial.

PURPOSE: Prospective comparison of the efficacy and safety of transforaminal endoscopic lumbar discectomy (TELD) with a 45° puncture angle versus traditional Thomas Hoogland endoscopy spine systems (THESYS) for the surgical treatment of L5/S1 lumbar disc herniation (LDH). METHODS: Consecutive patients with L5/S1 LDH who underwent TELD were randomized (1:1) assigned to the 45° TELD group and the THESYS group. Clinical outcomes were assessed at pre-operation, 1-day and 3/6-months post-operation till final follow-up. Surgical-related parameters, visual analogue scale (VAS) score, oswestry disability index (ODI), and modified MacNab criteria, and surgical complications were recorded and analysed. RESULTS: All patients were followed up for at least 24 months. Compared to the THESYS group, the 45° TELD group had a shorter operative time (P < 0.001) and intraoperative radiation time (P < 0.001) and a smaller VAS score for back pain (P < 0.001) and leg pain intraoperatively (P < 0.001). The VAS and ODI in the 45° TELD group were significantly better than those in the THESYS group within 3 months postoperatively. However, from 3 months on, both groups showed comparable VAS and ODI. There was no significant difference between the two groups of modified MacNab criteria. There were two cases of residual disc and two cases of recurrence that required reoperation in the THESYS group. CONCLUSION: For L5/S1 LDH, the 45° TELD technique was superior to traditional THESYS in terms of surgery-related parameters and faster improvement of VAS and ODI, with a lower complication rate.

Predicting and analysing of the unfavourable outcomes of early applicated percutaneous endoscopic interlaminar discectomy for lumbar disc herniation: development and validation based nomogram.

OBJECTIVE: To predict and analyse the unfavourable outcomes of early applicated percutaneous endoscopic interlaminar discectomy for lumbar disc herniation. METHODS: Information of 426 patients treated by early applicated percutaneous endoscopic interlaminar discectomy (PEID) for lumbar disc herniation (LDH) at our hospital from June 2017 to October 2021 in addition to 17 other features was collected. The risk factors were selected by the least absolute shrinkage and selection operator method (LASSO) regression. Then, a prediction model (nomogram) was established to predict the unfavourable outcomes of using the risk factors selected from LASSO regression. Bootstrap (n = 1000) was used to perform the internal validation, and the performance of the model was assessed by the concordance index (C-index), receiver operating characteristic curve, and calibration curve. The decision curve analysis (DCA) and clinical impact curve (CIC) were used to assess the clinical utility of the model, respectively. RESULTS: Finally, 53 of 426 patients showed unfavourable outcomes. Five potential factors, Modic change, Calcification, Lumbar epidural steroid injection preoperative, Articular process hyperplasia and cohesion, and Laminoplasty technique, were selected according to the LASSO regression, that identified the predictors to establish nomogram model. Meanwhile, the C-index of the prediction nomogram was 0.847, the area under the receiver operating characteristic curve value was 0.847, and the interval bootstrapping (n = 1000) validation C-index was 0.809. The model has good practicability for clinics according to the DCA and CIC. CONCLUSION: This nomogram model has good predictive performance and clinical practicability, which could provide a certain basis for predicting unfavourable outcomes of early applicated PEID for LDH.

Cervical vertebral Hounsfield units are a better predictor of Zero-P subsidence than the T-score of DXA in patients following single-level anterior cervical discectomy and fusion with zero-profile anchored spacer.

OBJECTIVES: To determine the predictive effect of Hounsfield unit (HU) values in the cervical vertebral body measured by computed tomography (CT) and T-scores measured by dual-energy X-ray absorptiometry (DXA) on Zero-P subsidence after anterior cervical discectomy and fusion (ACDF)with Zero-P. In addition, we evaluated the most reliable measurement of cervical HU values. METHODS: We reviewed 76 patients who underwent single-level Zero-P fusion for cervical spondylosis. HU values were measured on CT images according to previous studies. Univariate analysis was used to screen the influencing factors of Zero-P subsidence, and then, logistic regression was used to determine the independent risk factors. The area under the receiver operating characteristic curve (AUC) was used to evaluate the ability to predict Zero-P subsidence. RESULTS: Twelve patients (15.8%) developed Zero-P subsidence. There were significant differences between subsidence group and non-subsidence group in terms of age, axial HU value, and HU value of midsagittal, midcoronal, and midaxial (MSCD), but there were no significant differences in lowest T-score and lowest BMD. The axial HU value (OR = 0.925) and HU value of MSCD (OR = 0.892) were independent risk factors for Zero-P subsidence, and the lowest T-score was not (OR = 1.186). The AUC of predicting Zero-P subsidence was 0.798 for axial HU value, 0.861 for HU value of MSCD, and 0.656 for T-score. CONCLUSIONS: Lower cervical HU value indicates a higher risk of subsidence in patients following Zero-P fusion for single-level cervical spondylosis. HU values were better predictors of Zero-P subsidence than DXA T-scores. In addition, the measurement of HU value in the midsagittal, midcoronal, and midaxial planes of the cervical vertebral body provides an effective method for predicting Zero-P subsidence.

Cost-effectiveness of posterior versus anterior surgery for cervical radiculopathy: results from a multicentre randomised non-inferiority trial (FACET).

PURPOSE: For cervical nerve root compression, anterior cervical discectomy with fusion (anterior surgery) or posterior foraminotomy (posterior surgery) are safe and effective options. Posterior surgery might have a more beneficial economic profile compared to anterior surgery. The purpose of this study was to analyse if posterior surgery is cost-effective compared to anterior surgery. METHODS: An economic evaluation was performed as part of a multicentre, noninferiority randomised clinical trial (Foraminotomy ACDF Cost-effectiveness Trial) with a follow-up of 2 years. Primary outcomes were cost-effectiveness based on arm pain (Visual Analogue Scale (VAS; 0-100)) and cost-utility (quality adjusted life years (QALYs)). Missing values were estimated with multiple imputations and bootstrap simulations were used to obtain confidence intervals (CIs). RESULTS: In total, 265 patients were randomised and 243 included in the analyses. The pooled mean decrease in VAS arm at 2-year follow-up was 44.2 in the posterior and 40.0 in the anterior group (mean difference, 4.2; 95% CI, - 4.7 to 12.9). Pooled mean QALYs were 1.58 (posterior) and 1.56 (anterior) (mean difference, 0.02; 95% CI, - 0.05 to 0.08). Societal costs were €28,046 for posterior and €30,086 for the anterior group, with lower health care costs for posterior (€12,248) versus anterior (€16,055). Bootstrapped results demonstrated similar effectiveness between groups with in general lower costs associated with posterior surgery. CONCLUSION: In patients with cervical radiculopathy, arm pain and QALYs were similar between posterior and anterior surgery. Posterior surgery was associated with lower costs and is therefore likely to be cost-effective compared with anterior surgery.

A novel MRI-based Cervical-Endplate Bone Quality score independently predicts cage subsidence after Anterior Cervical Discectomy and Fusion.

INTRODUCTION: Postoperative cage subsidence after Anterior Cervical Discectomy and Fusion (ACDF) often has adverse clinical consequences and is closely related to Bone Mineral Density (BMD). Previous studies have shown that cage subsidence can be better predicted by measuring site-specific bone density. MRI-based Endplate Bone Quality (EBQ) scoring effectively predicts cage subsidence after lumbar interbody fusion. However, there is still a lack of studies on the practical application of EBQ scoring in the cervical spine. PURPOSE: To create a similar MRI-based scoring system for Cervical-EBQ (C-EBQ) and to assess the correlation of the C-EBQ with endplate Computed Tomography (CT)-Hounsfield Units (HU) and the ability of this scoring system to independently predict cage subsidence after ACDF, comparing the predictive ability of the C-EBQ with the Cervical-Vertebral Bone Quality (C-VBQ) score. METHODS: A total of 161 patients who underwent single-level ACDF for degenerative cervical spondylosis at our institution from 2012 to 2022 were included. Demographics, procedure-related data, and radiological data were collected, and Pearson correlation test was used to determine the correlation between C-EBQ and endplate HU values. Cage subsidence was defined as fusion segment height loss of ≥ 3 mm. Receiver operating characteristic analysis and area-under-the-curve values were used to assess the predictive ability of C-EBQ and C-VBQ. A multivariate logistic regression model was developed to identify potential risk factors associated with subsidence. RESULTS: Cage subsidence was present in 65 (40.4%) of 161 patients. The mean C-EBQ score was 1.81 ± 0.35 in the group without subsidence and 2.59 ± 0.58 in the group with subsidence (P < 0.001). Multivariate analysis showed that a higher C-EBQ score was significantly associated with subsidence (OR = 5.700; 95%CI = 3.435-8.193; P < 0.001), was the only independent predictor of cage subsidence after ACDF, had a predictive accuracy of 93.7%, which was superior to the C-VBQ score (89.2%), and was significantly negatively correlated with the endplate HU value (r = -0.58, P < 0.001). CONCLUSIONS: Higher C-EBQ scores were significantly associated with postoperative cage subsidence after ACDF. There was a significant negative correlation between C-EBQ and endplate HU values. The C-EBQ score may be a promising tool for assessing preoperative bone quality and postoperative cage subsidence and is superior to the C-VBQ.