Comparative study of neck pain in relation to increase of cervical epidural pressure during percutaneous endoscopic lumbar discectomy

Noninvasive intracranial pressure profile in 31 patients submitted to fullendoscopic spine surgery

PURPOSE

Full-endoscopic spine surgery (FESS) is associated with specific complications, possibly linked to increased intracranial pressure (ICP) resulting from continuous saline infusion into the epidural space. This study aimed to assess the impact of saline irrigation and its correlation with noninvasively obtained ICP waveform changes.

METHODS

Patients undergoing FESS between January 2019 and November 2020 were included. Noninvasive ICP (n-ICP) monitoring utilized an extracranial strain sensor generating ICP waveforms, from which parameters P2/P1 ratio and time to peak (TTP) values were derived and correlated to irrigation and vital parameters. Documentation occurred at specific surgical intervals (M0-preoperatively; M1 to M4-intraoperatively; M5-postoperatively). Mixed-model analysis of variance and multiple comparisons tests were applied, with M0 as the baseline.

RESULTS

Among 31 enrolled patients, three experienced headaches unrelated to increased ICP at M5. The P2/P1 ratio and TTP decreased during surgery (p < 0.001 and p < 0.004, respectively). Compared to baseline, P2/P1 ratio and vital parameters remained significantly lower at M5. No significant differences were observed for fluid parameters throughout surgery.

CONCLUSIONS

This study demonstrated a decline in the n-ICP parameters after anesthetic induction despite the anticipated increase in ICP due to constant epidural irrigation. The n-ICP parameters behaved independently of fluid parameters, suggesting a potential protective effect of anesthesia.

An Experimental Model for Fluid Dynamics and Pressures During Endoscopic Lumbar Discectomy

OBJECTIVE

Endoscopic spine surgery is an emerging technique of minimally invasive spine surgery. However, headache, seizure, and autonomic dysreflexia are possible irrigation-related complications following full-endoscopic lumbar discectomy (FELD). Pressure elevation through fluid irrigation may contribute to these adverse events. A validated experimental model to investigate parameters for guideline definition is lacking. This study aimed to create an experimental setting for FELD with pressure assessments to prove the concept of repeatable and sensitive measurement of intracranial, intra- and epidural pressures during spine endoscopy.

METHODS

To measure intradural pressure, catheters were introduced through a sacral approach and advanced to lumbar, thoracic, and cervical levels in human cadavers. Similarly, lumbar epidural and intracranial probes were placed. The dural sac was filled with Ringer solution to a physiologic pressure of 15 cmH2O. Lumbar endoscopy was performed on 3 human cadavers at the L3-4 level. Pressure changes were measured continuously at all sites and the effects of backflow-occlusion were monitored.

RESULTS

Reproducibility of the experimental model was validated with catheters at the correct locations and stable compartmental pressure baselines at all levels for 3 specimens (mean±standard deviation: 1.3±2.9 mmHg, 9.0±2.0 mmHg, 6.0±1.2 mmHg, respectively). Pressure increase could be detected sensitively by closing the system with backflow-occlusion.

CONCLUSION

An experimental setup for feasible, repeatable, and precise pressure measurement during FELD in a human cadaveric setup has been developed. This allows investigation of the effects of endoscopic techniques and pump pressures on intra-, epidural and intracranial pressure and enables ranges of safe pump pressures per clinical situations.

Prospective comparative analysis of three types of decompressive surgery for lumbar central stenosis: conventional, full-endoscopic, and biportal endoscopic laminectomy

Conventional open laminectomy has long been considered one of the important surgical options for lumbar central stenosis owing to its positive outcomes. However, newer approaches have emerged as alternatives, including full-endoscopic and biportal endoscopic laminectomy. Therefore, a comparison of the outcomes that are associated with each of these surgical methods is warranted. This prospective multicenter trial, initiated in February 2019, compared the outcomes of three lumbar central stenosis surgical approaches: open laminectomy (OPEN), uniportal endoscopy (UNIPORT), and biportal endoscopy (BIPORT). Among 115 participants from seven centers, one-year follow-ups assessed laboratory, radiological, and clinical outcomes. Despite all groups showing adequate decompression and clinical improvement, the OPEN group exhibited less improvement in Visual analog scale (VAS) for back pain scores (p < 0.05) and significant postoperative increases in most laboratory markers. Furthermore, the OPEN group experienced a significant decrease in multifidus muscle cross-sectional area compared to endoscopic groups (p < 0.001). Each surgical techniques produced similar clinical outcomes and dural space expansion. However, endoscopic surgery was associated with better muscle preservation and better relief of back pain. Endoscopic surgery is a reasonable alternative to conventional laminectomy for treating lumbar central stenosis.This trial was registered on CRIS (Clinical Research Information Service, KCT0004355).

Biportal Endoscopic Spinal Cord Stimulation Paddle Lead Implantation: Technical Note and Preliminary Clinical Results

OBJECTIVE

This study aims to elucidate a novel, minimally invasive surgical technique using a biportal endoscope for the implantation of spinal cord stimulation (SCS) paddle leads and to report the preliminary results of its clinical application.

MATERIALS AND METHODS

The perioperative data of patients who underwent the biportal endoscopic SCS paddle lead implantation in our department were collected; the surgical procedure was delineated, and the clinical outcomes were assessed.

RESULTS

From February 2022 to December 2023, six patients underwent biportal endoscopic SCS paddle lead implantation. The median follow-up time was nine months (range one to three months). The median intraoperative blood loss was 30 mL (range 25-50 mL), and the median operative time was 87.5 minutes (range 75-110 minutes). One patient experienced severe neck pain during the operation, whereas the other five patients experienced no surgical complications. One patient was found to have a slight lead migration three months after surgery, which did not affect the therapeutic effect. The median visual analogue scale (VAS) of the surgical area was 0.5 (range 0-2), 2.5 (range 1-4), and 0.5 (range 0-1) during the operation and one day and one week after the operation, respectively. The median VAS of the six patients' primary disease was 8 (range 7-9) before surgery and 2.5 (range 1-4) at the last postoperative follow-up (pain reduction ≥50%).

CONCLUSION

Paddle lead systems for SCS can be implanted successfully using a biportal endoscopic technique.

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.

Contrast enhancing epidural fluid accumulation after percutaneous endoscopic lumbar discectomy: A case report of recurrent disc herniation within pseudocyst secondary to irrigation fluid

INTRODUCTION

Percutaneous endoscopic lumbar discectomy (PELD) is increasingly being utilized to treat patients with lumbar disc herniation. PELD is unique in that it uses a single working port endoscope with constant irrigation of the surgical field to visualize pathology. The current report is of a case of postoperative epidural irrigation fluid accumulation presenting as peripherally enhancing epidural lesions, masking an underlying re-herniation.

PRESENTATION OF CASE

A patient with a Lumbar 5-Sacral 1 level disc herniation presenting with radiculopathy was treated using PELD. Following the operation, the patient experienced recurrent pain, prompting a repeat MRI of the lumbar spine. Multiple ring-enhancing lesions within the epidural space were observed, creating diagnostic dilemmas. The differential diagnoses included epidural abscess, pseudomeningocele from unintended durotomy, epidural hematoma, or trapped epidural fluid collection presenting as a pseudocyst with or without recurrent disc herniation. A repeat endoscopic discectomy was performed to confirm the diagnosis of pseudocyst, revealing a recurrent disc herniation.

DISCUSSION

Pseudocysts are not an uncommon complication of PELD, typically believed to be due to an inflammatory response to disc fragments. However, in this case, the epidural fluid collection was likely the result of trapped irrigation fluid from continuous irrigation during the procedure, which masked an underlying re-herniation on imaging.

CONCLUSION

With the increasing utilization of PELD, it is important to acknowledge unique complications such as fluid accumulation from irrigation within the epidural space. Fluid accumulation can lead to contrast-enhancing pseudocyst formation, which can theoretically lead to mass effect or increased intracranial and intraspinal pressure and may mask additional underlying pathology.

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.

Awake Unilateral Biportal Endoscopic Decompression Under Local Anesthesia for Degenerative Lumbar Spinal Stenosis in the Elderly: A Feasibility Study with Technique Note

Purpose

Here, we introduce a novel strategy of awake unilateral biportal endoscopic (UBE) decompression, which applies conscious sedation combined with stepwise local anesthesia (LA) as an alternative to general anesthesia (GA). The study aims to evaluate the feasibility of awake UBE decompression for degenerative lumbar spinal stenosis (DLSS) in elderly patients.

Patients and Methods

This retrospective study included 31 consecutive patients who received awake UBE decompression for DLSS in our institution from January 2021 to March 2022. Clinical results were evaluated using patient-reported outcomes measures (PROM) including visual analog scale for leg pain (VAS-LP), Oswestry Disability Index (ODI), and modified MacNab criteria. The anesthesia effectiveness and intraoperative experience were evaluated by intraoperative VAS and satisfaction rating system.

Results

UBE decompression was successfully performed in all patients under LA combined with conscious sedation. 26 (83.9%) patients rated the intraoperative experience as satisfactory (excellent or good) and 5 (16.1%) as fair. The mean intraoperative VAS was 3.41±1.26. The VAS and ODI at each follow-up stage after surgery were significantly improved compared to preoperative scores (p < 0.01). At the last follow-up, 28 patients (90.3%) classified the surgical outcome as good or excellent, and 3 (9.7%) as fair. There were no serious complications or adverse reactions observed in the study.

Conclusion

Our preliminary results suggest that awake UBE decompression is a feasible and promising alternative for elderly patients with DLSS.

Intracranial Pressure Evaluation in Swine During Full-Endoscopic Lumbar Spine Surgery

BACKGROUND

Neurological complications during full-endoscopic spine surgery (FESS) might be attributed to intracranial pressure (ICP) increase due to continuous saline infusion (CSI). Understanding CSI and ICP correlation might modify irrigation pump usage. This study aimed to evaluate invasive ICP during interlaminar FESS; correlate ICP with irrigation pump parameters (IPPs); evaluate ICP during saline outflow occlusion, commonly used to control bleeding and improve the surgeon's view; and, after durotomy, simulate accidental dural tear.

METHODS

Five swine were monitored, submitted to total intravenous anesthesia, and positioned ventrally. A parenchymal catheter was installed through a skull burr for ICP monitoring. Lumbar interlaminar FESS was performed until exposure of neural structures. CSI was used within progressively higher IPPs (A [60 mm Hg, 350 mL/minute] to D [150 mm Hg, 700 mL/minute]), and ICP was documented. During each IPP, different situations were grouped: intact dura with open channels (A1-D1) or occlusion test (A2-D2); dural tear with open channels (Ax1-Dx1) or occlusion test (Ax2-Dx2). ICP <20 mm Hg was defined as safe.

RESULTS

Basal average ICP was 8.1 mm Hg. Adjustment in total intravenous anesthesia or suspension of tests was necessary due to critical ICP or animal discomfort. It was safe to operate with all IPPs with opened drainage channels (A1-D1) even with dural tear (Ax1-Dx1). Several occlusion tests (A2-D2, Ax2-Dx2) caused ICP increase (e.g., 86.1 mm Hg) influenced by anesthetic state and hemodynamics.

CONCLUSIONS

During FESS, CSI might critically raise ICP. Keeping drainage channels open, with ideal anesthetic state, ICP remains safe even with high IPPs, despite dural tear. Drainage occlusions can quickly raise ICP, being even more severe with higher IPPs. Total intravenous anesthesia may protect from ICP increase and may allow longer drainage occlusion or higher IPPs.

Full-endoscopic anterior excision of thoracic disc herniations, including giant and calcified discs with spinal cord compression: surgical technique and outcomes

PURPOSE

Operations on thoracic herniated discs are comparatively rare and often demanding. An individual approach and mastery of different surgical techniques and surgical approaches are necessary. The main factors for the chosen surgical technique and approach are the anatomical localization, consistency of the pathology, the general condition of the patient and the experience of the surgeon. The purpose of this study was to evaluate the technical possibilities and outcomes of the full-endoscopic technique with interlaminar, extraforaminal and transthoracic retropleural approaches in patients with symptomatic herniated discs with anterior neural compression.

METHODS

In 49 patients with thoracic disc herniations, decompression was performed between 2016 and 2020, using a full-endoscopic interlaminar, extraforaminal or transthoracic retropleural approach. Clinical data and imaging were collected during follow-up of 18 months.

RESULTS

Sufficient decompression was achieved in all cases with the full-endoscopic surgical technique. Two patients experienced worsening of myelopathy, one of which was of transient duration, and one patient required reoperation for an epidural hematoma. No other complications were recorded. All other patients experienced a regression or improvement of symptoms.

CONCLUSION

The full-endoscopic technique with interlaminar, extraforaminal or transthoracic retropleural approach is a sufficient and minimally invasive method. All three full-endoscopic approaches of the thoracic spine are required to enable sufficient decompression of the anterior pathologies examined here.

One-hole split endoscope technique for migrated lumbar disc herniation: a single-centre, retrospective study of a novel technique

BACKGROUND

Lumbar disc herniation (LDH) is one of the most common diseases of the spine, and migrated LDH is a more serious type, associated with nerve root function injury or abnormality. Regarding the increasing surgery adoption of treating migrated LDH, we aimed to investigate the clinical efficacy and safety of discectomy with a novel technique-one-hole split endoscope (OSE) technique.

METHODS

This was a retrospective analysis of migrated LDH treated between December 2020 and September 2021. Hospitalization time, operative duration, intraoperative blood loss, number of fluoroscopy exposures, incision length, postoperative facet preservation rate, number of excellent-good cases, lower back and leg visual analogue score (VAS), Oswestry Disability Index (ODI) and surgical complications were compared between high-grade migration group (82 cases) and low-grade migration group (148 cases). The Macnab criteria was used to evaluate the clinical outcome. The Shapiro‒Wilk test was used to test measurement data, and the χ² test was used to test counting data.

RESULTS

There was no significant difference in hospitalization time, operative duration, intraoperative blood loss, number of fluoroscopy exposures, incision length or postoperative facet preservation rate between the two groups by independent sample t test or nonparametric test. At any time point, the lower back and leg VAS and ODI of the two groups were significantly improved compared to those before the operation, but there was no significant difference between the two groups at the same time point by two-way repeated measures ANOVA. There were two cases of postoperative nerve root stimulation symptoms in the high-grade migration group and three cases in the low-grade migration group. There was one patient reoperated in the high-grade migration group. There was no significant difference in number of excellent-good cases between the two groups. The overall excellent-good rate was 89.6%.

CONCLUSION

The OSE technique has the advantages of less trauma, faster recovery, complete removal of the nucleus pulposus and a satisfactory early clinical efficacy in the treatment of migrated LDH.

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.

Comparison of Outcomes between Unilateral Biportal Endoscopic and Percutaneous Posterior Endoscopic Cervical Keyhole Surgeries

Objective: The purpose of this study was to compare the clinical and radiological outcomes of unilateral biportal endoscopic (UBE) and percutaneous posterior endoscopic cervical discectomy (PE) keyhole surgeries. Methods: Patients diagnosed with cervical spondylotic radiculopathy (CSR) treated by UBE or PE keyhole surgery from May 2017 to April 2020 were retrospectively analyzed. The length of incision, fluoroscopic time, postoperative hospital stay, and total cost were compared. The clinical efficacy was assessed using a visual analog scale (VAS), neck disability index (NDI), and modified MacNab criteria. Moreover, the C2-7 Cobb’s angle, range of motion (ROM), intervertebral height, vertebral horizontal displacement, and angular displacement of the surgical segment were measured. Results: A total of 154 patients were enrolled, including 89 patients in the UBE group and 65 patients in the PE group, with a follow-up period of 24–32 months. Compared with PE surgery, UBE surgery required shorter fluoroscopic times (6.76 ± 1.09 vs. 8.31 ± 1.10 s) and operation times (77.48 ± 17.37 vs. 84.92 ± 21.97 min) but led to higher total hospitalization costs and longer incisions. No significant differences were observed in the postoperative hospital stay, bleeding volume, VAS score, NDI score, effective rate, or complication rate between the UBE and PE groups. Both the C2-7 Cobb’s angle and ROM increased significantly after surgery, with no significant differences between groups. There were no significant differences between intervertebral height, vertebral horizontal displacement, and angular displacement of the surgical segment at different times. Conclusions: Both UBE and PE surgeries in the treatment of CSR were effective and similar after 24 months. The fluoroscopic and operation times of UBE were shorter than those of PE.

Postoperative Intracranial Hemorrhage after an Endoscopic L5-S1 Laminectomy and Discectomy: A Case Report and Literature Review

BACKGROUND

Postoperative intracranial hemorrhage (PIH) is a fairly rare but catastrophic perioperative complication following lumbar spine surgery. This is a case report of a 54-year-old male patient who experienced PIH 2 h after an endoscopic L5-S1 laminectomy and discectomy.

CASE PRESENTATION

A 54-year-old male patient presented with right L5-S1 radiculopathy that corresponded with the picture revealed in medical imaging and the signs seen upon physical examination. Subsequently, he underwent endoscopic L5-S1 laminectomy and discectomy. The patient presented with idiopathic unconsciousness and limb twitching 2 h after surgery. An emergency cranial CT scan was obtained which demonstrated intracranial hemorrhage. Following an emergency consultation with the Department of Neurology and Neurosurgery, the patient underwent an emergency interventional thrombectomy as per their orders. The surgery was performed successfully. However, the patient's situation did not improve and he died on the second postoperative day.

CONCLUSION

PIH after spinal endoscopic surgery is a rare but horrible complication. Several factors could lead to PIH. However, in this patient, the cause of PIH might be attributed to the long operation time combined with cerebrospinal fluid (CSF) leakage. Great attention should be attached to the issue of PIH development in spinal endoscopic procedures due to constant irrigation. This study aims to highlight the issue of PIH following endoscopic spinal surgery by presenting a case report of a patient who died despite successful surgery.

Clinical Features and Management of Seizure After Percutaneous Endoscopic Spine Surgery: A Retrospective Case Series Analysis

OBJECTIVE

To describe the perioperative clinical features, management, and outcomes of patients with seizure after percutaneous endoscopic spine surgery (PESS).

METHODS

Patients who experienced seizure after PESS in a tertiary orthopedic hospital between January 2016 and June 2022 were retrospectively recruited, and patient charts were reviewed.

RESULTS

Twenty-nine patients were recruited, and the incidence of seizure after PESS was 0.52%. The operation time was 110.0 minutes (interquartile range [IQR], 82.5-235.0 minutes) and the irrigation speed was 109.0 mL/minute (IQR, 86.5-145.5 mL/minute). Definitive dural tears were reported in 15 patients (51.7%). In addition to agitation and myotonia, significant increased respiratory rate (29.9 ± 6.5 breaths/minute), tachycardia (112.1 ± 20.6 beats/minute), and hypertension (systolic, 189.5 ± 21.9 mm Hg; diastolic, 98.3 ± 10.6 mm Hg) were observed. Arterial blood gas analysis showed hypocapnia, metabolic acidosis, and hyperlactatemia. All patients received analgesia and sedation as well as hyperosmolar therapy. The estimated duration of seizure was 3.0 hours (IQR, 2.5-4.0 hours) and the postoperative length of hospital stay was 3.0 (IQR, 3.0-5.5) days. The Japanese Orthopaedic Association score and visual analog scale score improved markedly within 6 months after surgery.

CONCLUSIONS

Despite the low incidence and short duration, seizure after PESS should be considered a critical and urgent syndrome. Management strategies for seizure mainly involve intensive care, securing the airway, analgesia and sedation, hyperosmolar therapy, and negative fluid balance. No significant adverse effects of seizure on clinical outcomes were observed during 6 months of follow-up.

[Comparative analysis of unilateral biportal endoscopic discectomy, percutaneous endoscopic lumbar discectomy, and fenestration discectomy in treatment of lumbar disc herniation]

OBJECTIVE

To investigate the effectiveness of unilateral biportal endoscopic discectomy (UBED), percutaneous endoscopic lumbar discectomy (PELD), and traditional fenestration discectomy (FD) in the treatment of lumbar disc herniation (LDH).

METHODS

The clinical data of 347 LDH patients who met the selection criteria and underwent discectomy between January 2017 and December 2021 were retrospectively analyzed. They were divided into FD group (160 cases), PELD group (86 cases), and UBED group (101 cases) according to operation methods. There was no significant difference in gender, age, surgical level distribution, disease duration, and preoperative visual analogue scale (VAS) score and Oswestry disability index (ODI) between groups ( P>0.05). The operation time, hospitalization stay, treatment cost, and incidence of surgery-related complications were recorded and compared between groups. The patients' pain and functional recovery were evaluated by VAS score and ODI before and after operation.

RESULTS

The operation time of FD group was significantly shorter than that of PELD group and UBED group, and the hospitalization stay was significantly longer than that of PELD group and UBED group ( P<0.05); there was no significant difference between PELD group and UBED group ( P>0.05). The treatment cost in UBED group was significantly higher than that in PELD group, and in PELD group than in FD group ( P<0.05). All the patients were followed up 6-24 months, with an average of 14.6 months. VAS score of lower extremity and ODI in 3 groups significantly improved after operation when compared with that before operation ( P<0.05). At 1 day after operation, VAS score of lower extremity of UBED group was significantly better than that in PELD group and FD group ( P<0.05), but there was no significant difference between PELD group and FD group ( P>0.05). There was no significant difference in VAS scores of lower extremity between the 3 groups at 1 and 3 months after operation ( P>0.05). The difference of ODI before and after operation in FD group and UBED group was slightly better than that in PELD group ( P<0.05), and there was no significant difference between FD group and UBED group ( P>0.05). Incidence of surgery-related complications in FD group (20.0%) was significantly higher than that in PELD group (12.8%) and UBED group (6.9%), and PELD group was significantly higher than UBED group ( P<0.05). All the incision infection occurred in FD group (12 cases), symptomatic disc cyst and myeloid hypertension-like occurred in 1 case each in PELD group.

CONCLUSION

UBED, PELD, and FD have similar effectiveness on lower extremity pain in early LDH. Compared with FD, UBED and PELD have the advantage of shorter hospitalization stay and fewer complications.

Hemodynamic protective effects of epinephrine containing saline irrigation in biportal endoscopic lumbar surgery

During endoscopic orthopedic surgery, epinephrine mixed with irrigation saline is frequently used to improve visualization. By monitoring hemodynamic parameters throughout the procedure, we intended to discover the hemodynamic effect of epinephrine between the normal saline irrigation fluid without epinephrine group (NS) and normal saline irrigation fluid with epinephrine group (EPI). Patients who underwent 1-level lumbar decompression or discectomy surgery without fusion between August 2019 and July 2020 were reviewed retrospectively. The hemodynamic parameters were compared between the NS group and EPI group. As a second endpoint, the incidence of hypotension and hypertension events, expected blood loss, postoperative nausea and vomiting and postoperative epidural hematoma were compared between the 2 groups. The 2 groups were homogeneous in terms of age, sex, weight, height, body mass index (BMI), ASA physical status (ASA PS), and diagnosis. The incidence of hypotension events (67.2 % in the NS group, 45.7 % in the EPI group, P =.015) and severe hypotension events (51.7 % in the NS group, 28.6 % in the EPI group, P = .015) were less frequent in the EPI group. Only epinephrine had a significant protective effect through a multivariable analysis (P = .027, OR = 2.361) and in severe hypotension events, only epinephrine had a significant protective effect through a multivariable analysis (P = .011, OR = 2.818), and EBL was the risk factor through a multivariable analysis (P = .016, OR = 1.002) We believe that the addition of epinephrine to irrigation saline has hemodynamic protective effects in patients who underwent endoscopic lumbar surgery.

Diffuse symptomatic pneumocephalus after biportal endoscopic spinal surgery: illustrative case

BACKGROUND

Percutaneous endoscopic lumbar decompression is gaining attention as a minimally invasive surgery. Here, the authors report a rare complication of pneumocephalus caused by vacuum drain after biportal endoscopic spinal surgery (BESS) for lumbar stenosis.

OBSERVATIONS

A 79-year-old woman with spinal stenosis over the L4-5 level received BESS. No visible dural tear was encountered during surgery, and a vacuum drain was placed after surgery. Approximately 150 mL of cerebrospinal fluid was drained on postoperative day 1. Simultaneously, symptoms of intracranial hypotension were noted. Brain computed tomography (CT) revealed pneumocephalus. The patient was advised to have bed rest and hydration, and her symptoms improved subsequently. Follow-up brain CT indicated the resolution of pneumocephalus.

LESSONS

Pneumocephalus after endoscopic lumbar surgery is rare. Dural tear, high rate of normal saline irrigation, and vacuum drain placement are the associated risk factors.

Lumbar degenerative disease treated by percutaneous endoscopic transforaminal lumbar interbody fusion or minimally invasive surgery-transforaminal lumbar interbody fusion: a case-matched comparative study

Purpose

This study aimed to evaluate the clinical efficacy and imaging results of percutaneous endoscopic transforaminal lumbar interbody fusion (PETLIF) through comparing it with minimally invasive surgery-transforaminal lumbar interbody fusion (MISTLIF).

Materials and methods

We performed a retrospective analysis on patients with lumbar degenerative disease treated by PETLIF or MISTLIF from September 2017 to January 2019, and the patients were divided into two groups: the PETLIF group and the MISTLIF group. The clinical and imaging parameters of the two groups were evaluated.

Results

There was no significant difference between the two groups in complication rate. The operative time in the PETLIF group was significantly less than that in the MISTLIF group. Compared with those before operation, the postoperative VAS-L and VAS-B scores were significantly improved after operation in the both groups. In addition, the postoperative VAS-B score of the PETLIF group was significantly lower than that of the MISTLIF group. At the last follow-up, there was no significant difference between the two groups in the VAS-L score, VAS-B score, ODI score, and bony fusion rate.

Conclusions

Both PETLIF and MISTLIF could achieve satisfactory clinical outcomes in the treatment of lumbar degenerative disease, but our study suggested that PETLIF had less damage, rapid recovery after operation, and short discharge time.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-021-02841-4.

Subarachnoid hemorrhage after full endoscopic transforaminal lumbar interbody fusion: a case report

PURPOSE

Intracranial hemorrhage such as subarachnoid hemorrhage (SAH) is a rare but severe complication of spinal surgery. Current case reports of open lumbar surgery are typically accompanied by intraoperative dural tears and cerebrospinal fluid (CSF) leakage. We report a case of non-aneurysmal SAH without CSF leakage after full endoscopic transforaminal lumbar interbody fusion (FE-TLIF).

DESIGN

Case report and literature review.

RESULTS

A 62-year-old male patient underwent FE-TLIF for L4/5 lumbar spinal stenosis. There was no intraoperative dural tear or postoperative CSF leakage. The patient reported neck pain immediately after the surgery. Around 12 h after the surgery, the patient complained of mild headaches. One day after the surgery, the patient reported severe headaches, accompanied by nausea and vomiting. CT showed a high-density shadow in part of the sulcus and cistern, suggesting SAH. No apparent neurological symptoms were present. The patient's condition improved after conservative treatment including bed rest, fluid infusions, and blood pressure control. Twelve days after the surgery, CT and MRA of the brain showed no hemorrhage and the patient was discharged.

CONCLUSION

This case was among the first that developed SAH without CSF leakage after FE-TLIF. Although the underlying pathologic mechanism is unknown, epidural hypertension may be a possible cause of the hemorrhage. Timely CT or magnetic resonance imaging (MRI) examinations may help to detect this complication and initiate early treatment.

Comparative evaluation of posterior percutaneous endoscopy cervical discectomy using a 3.7 mm endoscope and a 6.9 mm endoscope for cervical disc herniation: a retrospective comparative cohort study

Background

Posterior percutaneous endoscopy cervical discectomy (p-PECD) is an effective strategy for the treatment of cervical diseases, with a working cannula ranging from 3.7 mm to 6.9 mm in diameter. However, to date, no studies have been performed to compare the clinical outcomes of the use of endoscopes with different diameters in cervical disc herniation (CDH) patients. The purpose of this study was to compare the clinical outcomes of patients with unilateral CDH treated with p-PECD using a 3.7 mm endoscope and a 6.9 mm endoscope.

Methods

From January 2016 to June 2018, a total of 28 consecutive patients with single-level CDH who received p-PECD using either the 3.7 mm or the 6.9 mm endoscope were enrolled. The clinical results, including the surgical duration, hospitalization, visual analog scale (VAS) score and modified MacNab criteria, were evaluated. Cervical fluoroscopy, CT, and MRI were also performed during follow-up.

Results

Tthere was a significant difference in regard to the average identification time of the “V” point (18.608 ± 3.7607 min vs. 11.256 ± 2.7161 min, p < 0.001) and the mean removal time of the overlying tissue (16.650 ± 4.1730 min vs. 12.712 ± 3.3079 min, p < 0.05) for the use of the 3.7 mm endoscope and the 6.9 mm endoscope, respectively. The postoperative VAS and MacNab scores of the two endoscopes were significantly improved compared with those the preoperative scores (p < 0.05).

Conclusion

The application of both the 3.7 mm endoscope and 6.9 mm endoscope represent an effective method for the treatment of CDH in selected patients, and no significant difference can be observed in the clinical outcomes of the endoscopes. The 6.9 mm endoscope shows superiority to the 3.7 mm endoscope in terms of the efficiency of “V” point identification, the removal of overlying soft tissue and the prevention of spinal cord injury. However, the 6.9 mm endoscope may be inferior to the 3.7 mm endoscope in regards to anterior foraminal decompression due to its large diameter; this result needs to be further evaluated with the support of a large number of randomized controlled trials.

Assessing changes in cervical epidural pressure during biportal endoscopic lumbar discectomy

OBJECTIVE

Biportal endoscopic spinal surgery has been performed for several years, and its effectiveness is well known; however, no studies on its safety, specifically intracranial pressure, have been conducted to date. The authors sought to evaluate the effect of biportal endoscopic lumbar discectomy on intracranial pressure by monitoring cervical epidural pressure (CEP) changes throughout the procedure.

METHODS

Twenty patients undergoing single-level biportal endoscopic lumbar discectomy were enrolled in this study. CEPs were monitored throughout the procedure, consisting of phase 1, establishing the surgical portal and working space; phase 2, performing decompression and discectomy; and phase 3, turning off the fluid irrigation system. After discectomy was completed, the authors evaluated changes in CEP as the irrigation pressure increased serially by adding phase 4, increasing irrigation pressure with outflow open; and phase 5, increasing irrigation pressure with outflow closed.

RESULTS

The mean baseline CEP was measured as 16.65 mm Hg. In phase 1, the mean CEP was 17.3 mm Hg, which was not significantly different from the baseline CEP. In phase 2, the mean CEP abruptly increased up to 35.1 mm Hg when the epidural space was first connected with the working space, followed by stabilization of the CEP at 31.65 mm Hg. In phase 4, the CEP increased as the inflow pressure increased, showing a linear correlation, but not in phase 5. No patients experienced neurological complications.

CONCLUSIONS

It is important to ensure that irrigation fluid is not stagnant and is maintained continuously. More attention must be paid to keeping pressures low when opening the epidural space.

Seizures after percutaneous endoscopic lumbar discectomy: A case report

RATIONALE

Percutaneous endoscopic lumbar discectomy (PELD) is a minimally invasive technique for removing nucleus pulposus and achieving neural decompression via a posterolateral approach. PELD is known to have a very low rate of complications during the perioperative period. Although quite rare, seizures can occur in patients undergoing PELD.

PATIENT CONCERNS

A 58-year-old man with severe low back pain underwent the PELD procedure under general anesthesia. During the recovery phase after general anesthesia, the patient developed a tonic-clonic seizure. Two additional episodes occurred subsequently.

DIAGNOSES

Bilateral disc swelling indirectly supports the diagnosis of intracranial hypertension.

INTERVENTIONS

Midazolam and propofol were administered to control seizures. 1.0 g phenobarbital sodium was administered by intravenous injection. Ten milligrams of furosemide and 250 mL of mannitol (20%) were prescribed sequentially. Two hundred milligrams of hydrocortisone and an ice bag were used to protect the brain. Urapidil, metoprolol, and nicardipine were intermittently used to control his blood pressure. A sustained release of sodium valproate was administered and continued prophylactically for 4 weeks.

OUTCOMES

No further seizures were recorded and the patient recovered well.

LESSONS

We conclude that total volume of fluid used for irrigation was considered a possible cause of seizure. This case illustrates the fact that irrigation should be performed cautiously in PELD procedure. And anesthesiologists should be familiar with the management strategies of perioperative acute seizures.

Full-endoscopic decompression for thoracic ossification of ligamentum flavum: surgical techniques and clinical outcomes: A retrospective clinical study

BACKGROUND

Many complications are associated with thoracic open decompression surgery, such as dural tears and neurological deficits. The clinical outcomes are also not satisfactory. Full-endoscopic decompression of the lumbar spinal canal has achieved satisfactory results for the treatment of lumbar spinal stenosis. This surgery may be used for the treatment of thoracic ossification of the ligamentum flavum (OLF) under local anesthesia. The aim of our study is to introduce the surgical techniques used for full-endoscopic decompression for thoracic OLF and to evaluate its safety and efficacy.

METHODS

Fourteen patients with thoracic OLF (4 combined with dural ossification) underwent full-endoscopic decompression surgery. An interlaminar approach was performed. The anchoring method was used to establish the working passage. Spinal cord exposure began at a space between the ossification and the spinal cord, and dorsal and contralateral decompression were performed with the "Over the Top" technique. The modified Japanese Orthopedic Association score (11 points) was used to evaluate the efficacy during follow-up. At the same time, the visual analogue scale score for assessing back pain before and after the operation was evaluated.

RESULTS

The average operation time was 159.73 ± 62.09 minutes, and the hospitalization time was 7.43 ± 1.79 days. The follow-up period ranged from 8 to 22 months. Neurological function was improved. There were no serious complications. Dural tears occurred in 5 patients, intraoperative neurological deterioration occurred in 1 patient, and intraoperative headache and neck pain occurred in 1 patient.

CONCLUSION

Full-endoscopic decompression is an effective, safe surgical technique for thoracic OLF even the cases combined with dural ossification.

Safety Evaluation of Biportal Endoscopic Lumbar Discectomy: Assessment of Cervical Epidural Pressure During Surgery

STUDY DESIGN

A prospective study.

OBJECTIVE

To evaluate the change in cervical epidural pressure (CEP) during biportal endoscopic lumbar discectomy (BELD).

SUMMARY OF BACKGROUND DATA

In percutaneous uniportal endoscopic lumbar discectomy, irrigation fluid (IF) introduced into the spinal canal during surgery can compress the thecal sac, and act as a potential risk for neurological complications by disturbing cerebrospinal fluid (CSF) circulation and increasing intracranial pressure.

METHODS

Thirty consecutive patients, who underwent BELD, which was performed under automated pump system, an infusion pressure of 30 mmHg were enrolled. The change in CEP on C7-T1 level was measured. CEP was measured in each of the five phases of the procedure (1st phase-making surgical portals; 2nd phase-creating a workspace; 3rd phase-performing neural decompression and discectomy; 4th phase-factitious increase of pressure by clogging the outflow; 5th phase-dismission from fluid irrigation system). Neurological complications and independent risk factors were evaluated.

RESULTS

In the final 27 patients, changes in CEP during surgery were similar. The baseline CEP was 14.8 ± 2.8 mmHg, and the mean CEP in the 3rd phase 18.8 ± 5.1 mmHg was not significantly higher. In the 4th phase, however, the CEPs rose with linear correlation as the pressure increased. In the 5th phase, the elevated CEP returned to baseline in 2.5 ± 5.6 minutes. No patient had neurological complications. No statistically significant risk factors were observed.

CONCLUSION

In BELD, which is performed to allow continuous lavage with infusion pressure set to 30 mmHg, CEP does not increase beyond the physiological range. Therefore, BELD may be considered as a potentially safe technique.

LEVEL OF EVIDENCE

4.

Biportal endoscopic technique in the treatment of spinal stenosis: early clinical experiences and results

OBJECTIVE

Minimally invasive procedures in spine surgery have undergone significant development in recent times. A demand emerged from both surgeons and patients to develop and perform these types of surgeries in order to prevent biomechanical and surgical complications. Our study aimed to present early clinical results of a biportal endoscopy technique in the treatment of degenerative spinal stenosis.

METHOD

We created a retrospective database of patients who underwent biportal spinal endoscopic decompression at the National Institute of Clinical Neuroscience, Department of Neurosurgery, Semmelweis University, Budapest, Hungary, in 2019. The surgical steps of technique is discussed in details.

RESULTS

Retrospectively, we identified and collected 21 patients in our retrospective analysis. The early results after endoscopic decompression were excellent, 17 patients (81%) mentioned good general comfort which coincided with small incisions and the preservation of posterior spinal muscles. Three patients (14%) mentioned good condition and minor postoperative pain which could be controlled with analgesics. One patients (5%) mentioned postoperative discomfort. The patients were controlled at 3, 6 and 9 months. The mean follow-up time was 7 months.

DISCUSSION

Biportal endoscopic technique was developed to fulfil the requirements of minimally invasive techniques. Our results indicate this method may be highly effective for the treatment of lumbar spinal stenosis and an alternative to conventional microsurgical decompression; however, our study limited by its retrospective manner and small population size.

Interlaminar Endoscopic Lumbar Discectomy Using a New 8.4-mm Endoscope and Nerve Root Retractor

STUDY DESIGN

Surgical technique.

OBJECTIVE

Using an 8.4-mm endoscope and endoscopic nerve root retractor, the interlaminar endoscopic lumbar discectomy (IELD) technique is introduced for lumbosacral levels.

SUMMARY OF BACKGROUND DATA

Although spine surgeons are familiar with IELD, this technique is only used for L5-S1 disk herniations and requires a wide interlaminar space.

METHODS

Using an 8.4 mm-endoscope, high-speed drill, and endoscopic Kerrison punches, a nerve-root retractor facilitated the simultaneous medial retraction of the nerve root and removal of the disk fragment by the instrument's cannula. Clinical parameters such the visual analog scale scores for back and leg pain, modified Macnab criteria, and Oswestry Disability Index were analyzed.

RESULTS

A total of 101 patients were enrolled. The visual analog scale scores for back and leg pain significantly decreased from 6.8±2.1 and 7.8±1.5 to 2.0±0.6 and 1.78±1.1, respectively, at the 1-year follow up (P<0.01). The Oswestry Disability Index score significantly improved from 28.6±11.7 to 7.4±2.9 (P<0.01). Ninety-nine patients (97.1%) showed good outcomes.

CONCLUSIONS

A new IELD technique and instruments can overcome the drawbacks of existing IELD with adequate bone work and control of the affected nerve root.

Biportal endoscopic spine surgery (BESS): considering merits and pitfalls

The biportal endoscopic spine surgery allow us to use conventional spine surgical instruments in the endoscopic procedure like open surgery. And protection of the neural structures with assistant retractor make this procedure safer than the uniportal endoscopic spine surgery. The authors present a novel technique in treating degenerative spinal diseases in variable access angle different from the conventional uniportal endoscopic spine surgeries. The main objective of this report is presenting two approaches for central and extraforaminal stenosis using an assistant retractor. Both central and foraminal stenosis were well decompressed and a migrated disc fragment was removed successfully with this minimal endoscopic procedure without major complications in these cases.

Seizure After Percutaneous Endoscopic Surgery-Incidence, Risk Factors, Prevention, and Management

BACKGROUND

Percutaneous endoscopic surgery is a popular surgery to treat lumbar spinal disorders. However, seizure after percutaneous endoscopic surgery is an unpredictable complication. The only prodromal sign for seizure currently known is neck pain. We reviewed the incidence of, and risk factors for, seizure during percutaneous endoscopic surgery and present the cases of 3 patients with seizure and our management.

CASE DESCRIPTION

From October 2006 to March 2019, 3 of 816 patients (0.34%) with thoracic lumbar disorders who had undergone percutaneous endoscopic surgery experienced a seizure episode. The cases of those 3 patients were carefully reviewed. Studies of the risk factors for seizure after spinal procedures reported before June 13, 2019 were identified through a PubMed search. We found that infusion fluid containing cefazolin, the infusion rate, a prolonged operative time, the occurrence of a dural tear, and sevoflurane anesthesia might be associated with seizure, both described in the reported data and found in our experience. Three patients who experienced a seizure episode had had general anesthesia with sevoflurane, and the surgical approach used was interlaminar for a herniated disc in L5-S1. We noted a "red flag sign," namely an uncontrollable hypertension episode combined with a decreasing pulse rate, in all 3 patients who had experienced a seizure, which was not observed in the other patients. All 3 patients had received antihypertensive medication (labetalol) ≥3 times without response.

CONCLUSION

Seizure after percutaneous endoscopic surgery is rare, but lethal. Although its cause remains unknown, all risk factors for seizure should be checked and corrected immediately when a red flag sign, uncontrolled hypertension, appears.

Surgical treatment of cervical radiculopathy using an anterior cervical endoscopic decompression

Background

Anterior endoscopic cervical decompression with discectomy and foraminotomy is an alternative to open surgical treatment of unrelenting cervical radiculopathy (CR) in patients who have failed non-operative treatment. The purpose of the study is to present the clinical outcomes of patient with CR treated with an anterior endoscopic approach.

Methods

We reviewed the medical records of 293 patients diagnosed with CR and treated with an anterior endoscopic cervical decompression between 1997 and 2018. Primary outcome measures were modified Macnab as well as pre- and postoperative visual analog scale (VAS) criteria.

Results

The average surgical time was 65 minutes. At 12 months follow-up, Excellent and Good Macnab outcomes were achieved in 90.1% of patients. The average VAS score reduction was 5.6. Complications occurred in 8 patients and were treated with a second procedure in 10 patients.

Conclusions

The anterior endoscopic cervical decompression is an attractive alternative to open anterior cervical discectomy and fusion (ACDF) with a low complication and reoperations rate.

Surgical treatment of cervical subaxial intraspinal extradural cysts using a full-endoscopic uniportal posterior approach

PURPOSE

Symptomatic intraspinal extradural cysts of the cervical subaxial spine are rare, but usually require surgery. Conventional posterior decompression is the gold standard. However, there is increasing experience with endoscopic surgical techniques. The purpose of the study is to evaluate the technical implementation and outcomes of a full-endoscopic uniportal technique via the posterior approach in patients with symptomatic intraspinal extradural cysts of the cervical subaxial spine.

METHODS

Seven consecutive patients with a subaxial location of symptomatic intraspinal extradural cysts were decompressed in a full-endoscopic uniportal technique via the posterior approach between 2009 and 2015. Imaging and clinical data were collected in follow-up examinations for 18 months.

RESULTS

In all cases, the cyst was completely removed and adequate decompression was achieved using the full-endoscopic uniportal technique. One patient developed a dural leak that was sutured and covered intraoperatively. No other complications requiring treatment were observed. All patients had a good clinical outcome with stable regression of the radicular and central nerve pain or neurological deficits. The imaging follow-up showed sufficient decompression in all cases. No evidence was found of increasing instability during the follow-up period.

CONCLUSION

The full-endoscopic uniportal operation with a posterior approach allows the resection of the cyst and can minimize trauma and destabilization and has technical benefits and a low complication rate. It is an alternative surgical method that can offer advantages and is considered by the authors to be the surgical technique of choice for cervical subaxial intraspinal extradural cysts.

Step-by-Step Sublaminar Approach With a Newly-Designed Spinal Endoscope for Unilateral-Approach Bilateral Decompression in Spinal Stenosis

OBJECTIVE

Spinal stenosis is increasingly common due to population aging. In elderly patients with lumbar central canal stenosis (LCCS), minimizing muscle damage and bone resection is particularly important. We performed a step-by-step operation with a newly designed spinal endoscope to obtain adequate decompression in patients with spinal stenosis.

METHODS

From April 2015 to August 2016, 78 patients (48 males, 30 females) with LCCS (91 segments) underwent endoscopic decompression using a newly designed endoscope system. The inclusion criteria were: (1) neurogenic intermittent claudication with or without radiculopathy, (2) LCCS, and (3) having exhausted conservative treatment (>3 months). The exclusion criteria were: (1) >10° of instability, (2) spondylolisthesis grade II or greater according to the Meyerding criteria, (3) foraminal stenosis, (4) vascular intermittent claudication, (5) infection, and (6) stenosis combined with malignancy. We performed a step-by-step procedure using a newly designed endoscope system for unilateral-approach bilateral decompression. We used the same incision for 2-3 segments, only moving the skin.

RESULTS

The mean follow-up was 2.3±1.3 years. Excellent or good results were found according to the MacNab criteria in 85.9% of cases (67 of 78). The visual analogue scale, Japanese Orthopedic Association score, and Oswestry Disability Index showed significant decreases at 1 month, persisting until the 2-year follow-up. Dural tear occurred in 4 cases (5.1%), and patch repair was performed under endoscopy. No patients experienced aggravated instability requiring surgery.

CONCLUSION

We obtained good results with endoscopic decompression surgery using a newly designed instrument that minimized muscle and bone damage in elderly patients with spinal stenosis.

The full-endoscopic uniportal technique for decompression of the anterior craniocervical junction using the retropharyngeal approach: an anatomical feasibility study in human cadavers and review of the literature

Objective

Acute or progressive myelopathy may necessitate direct anterior decompression of the craniocervical junction and odontoidectomy. Different techniques with individual advantages and disadvantages can be used. In addition to the gold standard-the transoral approach-there is also increasing experience with the endoscopic transnasal technique. Other alternative methods are also being developed to reduce technical and perioperative problems. The aim of this anatomical study was to investigate the feasibility of the full-endoscopic uniportal technique with a retropharyngeal approach for decompression of the craniocervical junction, taking into consideration the specific advantages and disadvantages compared with conventional methods and the currently available data in the literature.

Methods

Five fresh adult cadavers were operated on. The endoscope used has a shaft cross-section of 6.9 × 5.9 mm and a 25° viewing angle. It contains an eccentric intraendoscopic working channel with a diameter of 4.1 mm. An anterior retropharyngeal approach was used. The anatomical structures of the anterior craniocervical junction were dissected and the bulbomedullary junction was decompressed.

Results

The planned steps of the operation were performed in all cadavers. The retropharyngeal approach allowed the target region to be accessed easily. The anatomical structures of the anterior craniocervical junction could be identified and dissected. The bulbomedullary junction could be adequately decompressed. No resections of the anterior arch of the atlas were necessary in the odontoidectomy.

Conclusions

Using the full-endoscopic uniportal technique with an anterior retropharyngeal approach, the craniocervical region can be adequately reached, dissected, and decompressed. This is a minimally invasive technique with the known advantages of an endoscopic procedure under continuous irrigation. The retropharyngeal approach allows direct, sterile access. The instruments are available for clinical use and have been established for years in other operations of the entire spine.

Transforaminal Percutaneous Endoscopic Lumbar Decompression by Using Rigid Bendable Burr for Lumbar Lateral Recess Stenosis: Technique and Clinical Outcome

Background

Open laminectomy has been regarded as the standard surgical procedure for lumbar lateral recess stenosis during the last decades. Although percutaneous endoscopic lumbar decompression has led to successful results comparable with open decompression, its application in LSS with is still challenging and technically demanding. Here, we report the surgical procedure and preliminary clinical outcomes of transforaminal percutaneous endoscopic lumbar decompression (PELD) by using flexible burr for lumbar lateral recess stenosis.

Method

A retrospective study was performed for the patients with lumbar lateral recess stenosis receiving PELD by using flexible burr. The indications of surgery were moderate to severe stenosis, persistent neurological symptoms, and failure of conservative treatment. The patients with mechanical back pain, more than grade I spondylolisthesis, or radiographic signs of instability were not included. Before the operation, the transforaminal epidural lidocaine injections were carried out to make the diagnosis more precise and accurate. Radiologic findings were investigated, and visual analog scale (VAS) for back and leg pain, Oswestry Disability Index, and modified Macnab criteria were analyzed at the different time of preoperation, postoperation, 3 months, 6 months, and 12 months.

Results

The follow-up period was 12 months. The mean VAS scores for back and leg pain immediately improved from 7.9 ± 1.2 to 2.8± 1.3, 2.4 ± 1.0, and 2.3 ± 1.0, respectively. The mean visual analog scale scores (VAS) for back pain and leg pain were significantly improved after PELD. The preoperative ODI dropped from 69.1 ± 7.3 to 25.9 ± 8.7, 25.0± 6.9, and 24.7 ± 6.4, respectively. The final outcome was excellent in 39.6%, good in 47.9%, fair in 8.3%, and poor in 4.17%. 87.5% of excellent-to-good ratio was achieved on the basis of Macnab criteria at postoperative 12 months. The complications were limited to transient postoperative dysesthesia (one case), temporary pain aggravation (six cases), and neck pain during the operation (one case).

Conclusion

This observation suggests that the clinical outcomes of PELD for lateral recess stenosis were excellent or showed good results. This minimally invasive technique would be helpful in choosing a surgical method for lateral recess stenosis.

Feasibility of Endoscopic Inspection of Pedicle Wall Integrity in a Live Surgery Model

Background

Perforations of the pedicle wall during cannulation can occur with experienced surgeons. Direct endoscopic visualization has not been used to inspect pedicles previously due to bone bleeding obscuring the camera visualization. The hypothesis of this study was that endoscopic visualization of pedicle wall integrity was technically feasible and would enable identification of clinically significant pedicle breaches.

Methods

A live porcine model was used. Eight lumbar pedicles were cannulated. Clinically significant breaches were created. An endoscope was introduced and was used to inspect the pedicles.

Results

All lumbar pedicles were endoscopically visible at a systolic pressure of 100 mm Hg. Clinically relevant anatomic structures and iatrogenic pathology, such as medial, lateral, and anterior breaches, were identified. There were no untoward events resulting from endoscopic inspection of the pedicle endosteal canal.

Conclusions

Endoscopic inspection of lumbar pedicles was safe and effective. The findings on endoscopic inspection corresponded with the ball-tip probe palpation techniques. Additional techniques, such as selection between 2 tracts, was possible with the endoscopic technique.

Percutaneous Endoscopic Lumbar Discectomy Versus Posterior Open Lumbar Microdiscectomy for the Treatment of Symptomatic Lumbar Disc Herniation: A Systemic Review and Meta-Analysis

OBJECTIVE

The purpose of this systematic review and meta-analysis was to compare the clinical efficacy between percutaneous endoscopic lumbar discectomy (PELD) versus posterior open lumbar microdiscectomy (OLMD) for the treatment of symptomatic lumbar disc herniation.

METHODS

We performed a comprehensive retrieval of related studies in 4 electronic databases (PubMed, Embase, Web of Science, and the Cochrane Library). Randomized or nonrandomized controlled trials reported from January 1990 to December 2017 that compared PELD versus OLMD for the treatment of symptomatic lumbar disc herniation were acquired. The quality of randomized controlled trials was evaluated by the criteria of the Cochrane Back Review Group, and the quality of cohort studies was assessed according to the Newcastle-Ottawa Scale. The primary outcome measurements included preoperative and postoperative visual analog scale (VAS) score of sciatica; the Oswestry Disability Index (ODI) before and after surgery; the Excellent and Good outcome rate based on Macnab criteria. The secondary outcome measurements included the incidence of complication, residual disk, recurrence, and reoperation; operation time; hospital stay; and time to return to work. Two authors independently extracted data and assessed each study for quality.

RESULTS

Nine studies with 1585 patients were included in our meta-analysis. Two were randomized controlled trials and the remaining 7 were retrospective cohort studies. The forest plots showed that no statistically significant difference was observed between the 2 groups in terms of preoperative and postoperative VAS score of sciatica, ODI before and after surgery, the Excellent and Good outcome rate, the complication rate, and the incidence of recurrence and reoperation. However, the PELD group had a higher incidence of residual disk or incomplete decompression than did the OLMD group. In addition, no significant difference was detected in the operation time between the 2 groups, but the PELD group was associated with shorter hospital stay and time of return to work.

CONCLUSIONS

Based on the present meta-analysis, no significant difference existed in VAS and ODI scores between the 2 surgical procedures, and they were also similar in terms of operation time, complication rate, and incidence of recurrence and reoperation, but PELD showed shorter hospital stay and time of return to work. Thus, under the premise of careful manipulation and complete decompression, we consider that PELD is a relatively more minimally invasive technique, which could be an alternative to OLMD.

Full-endoscopic uniportal retropharyngeal odontoidectomy for anterior craniocervical infection

BACKGROUND

Infections of the anterior craniocervical junction may require surgery. There are various techniques with individual advantages and disadvantages. This study evaluates the full-endoscopic uniportal technique via the anterior retropharyngeal approach for odontoidectomy, decompression, and debridement.

MATERIAL AND METHODS

Three patients with an infection of the anterior craniocervical junction with retrodental involvement were operated on between 2014 and 2016 using the full-endoscopic uniportal technique. Posterior stabilization was also performed with the same procedure for all patients.

RESULTS

The operation was technically satisfactory in all cases. No problems due to swelling of the pharyngeal soft tissue occurred. No other complications were observed. All patients had a satisfactory outcome with stable regression of the myelopathy symptoms and/or complete healing of the infection. The follow-up images showed sufficient decompression of bone and soft tissues in all cases.

CONCLUSIONS

The full-endoscopic uniportal technique with an anterior retropharyngeal approach can be an adequate and minimally invasive surgical technique for odontoidectomy, decompression, and debridement in infections of the craniocervical junction and can reduce access-related problems. The transoral, transnasal, and retropharyngeal approaches have different surgical fields due to the access trajectories, which must be taken into consideration depending on the anatomy and pathology when selecting a suitable technique.

Full-endoscopic Uniportal Odontoidectomy and Decompression of the Anterior Cervicomedullary Junction Using the Retropharyngeal Approach

STUDY DESIGN

A study of a series of consecutive full-endoscopic uniportal decompressions of the anterior craniocervical junction with retropharyngeal approach.

OBJECTIVE

The aim of this study was to evaluate the direct anterior decompression of the craniocervical junction in patients with bulbomedullary compression using a full-endoscopic uniportal technique via an anterolateral retropharyngeal approach.

SUMMARY OF BACKGROUND DATA

Acute or progressive myelopathy may necessitate direct anterior decompression of the craniocervical junction and odontoidectomy. Different techniques with individual advantages and disadvantages can be used. In addition to the gold standard - the transoral approach - there is increasing experience with the endoscopic transnasal technique. Other alternative procedures are also being developed.

METHODS

Between 2013 and 2016, eight patients with basilar impression, retrodental pannus, or retrodental infection were operated in the full-endoscopic uniportal technique with a retropharyngeal approach. Anterior decompression of the bulbomedullary junction with odontoidectomy was performed. All patients additionally underwent posterior stabilization. Imaging and clinical data were collected in follow-up examinations for 1 year.

RESULTS

The bulbomedullary junction was adequately decompressed. No problems due to swelling of pharyngeal soft tissue occurred. One patient required revision due to secondary bleeding. No other complications were observed. All patients had a good clinical outcome with stable regression of the myelopathy symptoms and/or healing of the infection. The imaging follow-up showed sufficient decompression of bone and soft tissue in all cases. No evidence was found of increasing instability or failure of posterior fusion.

CONCLUSION

In the operated patients, the full-endoscopic uniportal surgical technique with anterior retropharyngeal approach was found to be a sufficient and minimally invasive method with the known advantages of an endoscopic procedure under continuous irrigation. It should not be viewed only as competition for other surgical techniques - due to its individual technical parameters, it can also be considered to be an alternative or complementary procedure.

LEVEL OF EVIDENCE

4.

Full-endoscopic uniportal decompression in disc herniations and stenosis of the thoracic spine using the interlaminar, extraforaminal, or transthoracic retropleural approach

OBJECTIVE Surgery for thoracic disc herniation and spinal canal stenosis is comparatively rare and often challenging. Individual planning and various surgical techniques and approaches are required. The key factors for selecting the technique and approach are anatomical location, consistency of the pathology, general condition of the patient, and the surgeon's experience. The objective of the study was to evaluate the technical implementation and outcomes of a full-endoscopic uniportal technique via the interlaminar, extraforaminal, or transthoracic retropleural approach in patients with symptomatic disc herniation and stenosis of the thoracic spine, taking specific advantages and disadvantages and literature into consideration. METHODS Between 2009 and 2015, decompression was performed in 55 patients with thoracic disc herniation or stenosis using a full-endoscopic uniportal technique via an interlaminar, extraforaminal, or transthoracic retropleural approach. Imaging and clinical data were collected during follow-up examinations for 18 months. RESULTS Sufficient decompression was achieved in the full-endoscopic uniportal technique. One patient required revision due to secondary bleeding, and another exhibited persistent deterioration on myelopathy. No other serious complications were observed. All but one patient experienced regression or improvement of their symptoms. CONCLUSIONS The full-endoscopic uniportal technique with an interlaminar, extraforaminal, or transthoracic retropleural approach was found to be a sufficient and minimally invasive method. To cover the entire range of thoracic disc herniations and stenosis within the criteria named, all full-endoscopic approaches are required.

Percutaneous endoscopic cervical discectomy: a technical review

The treatment of cervical disc herniations has evolved in the last 2 decades. While the anterior cervical discectomy and fusion continues being the gold standard for the treatment of radicular pain triggered by cervical disc herniation, other surgical approaches have been developed. Percutaneous endoscopic cervical discectomy has demonstrated the ability to decompress the exiting nerve root and dural sac correctly and encouraging clinical outcomes has been reported in the literature. One of the most important advantages offered by the endoscopic technique is the capability to resolve the patient's symptoms without the need for interbody fusion. Also, a specific and selective decompression under continuous visualization with minimal surgery-related trauma can be achieved. There are two percutaneous endoscopic cervical discectomy approaches: anterior and posterior. The decision to perform each other depends on pathology site. However, the endoscopic technique requires previous surgical training, a steep learning curve, and proper patient selection. The development of new hardware such as endoscopes with better optics, lighting systems, and endoscopic surgical tools have allowed using endoscopic techniques in more complex cases. The objective of this review is the technical description of the anterior and posterior percutaneous endoscopic cervical discectomy.

Comparison of percutaneous endoscopic lumbar discectomy versus open lumbar microdiscectomy for lumbar disc herniation: A meta-analysis

PURPOSE

The purpose of the study is to perform a systematic review and meta-analysis to evaluate the clinical results of percutaneous endoscopic lumbar discectomy (PELD) and open lumbar microdiscectomy (OLM) for the treatment of lumbar disc herniation (LDH).

METHODS

Randomized controlled trials or non-randomized controlled trials published from the time when databases were built to March 2016 that compared the clinical effectiveness of PELD and OLM surgical approaches for the treatment of LDH were acquired by a comprehensive search in four electronic databases (PubMed, EMBASE, Web of Science and Cochrane library). A total of 7 studies (1389 patients) were included in this systematic review and meta-analysis. Pooled mean differences (MD) and odds ratios (OR) and with 95% CIs were calculated for the outcomes.

RESULT

The results showed that there were no statistically between the PELD group and OLM group in terms of preoperative VAS-BP score (WMD = 0.03; 95% CI: -0.99 to 1.05; P = 0.95), postoperative VAS-BP score (WMD = -0.56; 95% CI: -1.43 to 0.31; P = 0.21), postoperative ODI (WMD = -0.98; 95% CI: -4.96 to 3.00; P = 0.63), complication rate (OR = 1.79; 95% CI: 0.95 to 3.37; P = 0.07) or reoperation rate (OR = 1.44; 95% CI: 0.94 to 2.20; P = 0.09). PELD group was associated with shorter operation time (WMD = -12.83; 95% CI: -24.79 to -0.87; P = 0.04) and hospital stay (WMD = -5.49; 95% CI: -8.63 to -2.35; P = 0.0006).

CONCLUSION

The existing evidence indicate that no superiority exists between the two surgical approaches for the treatment of LDH in terms of functional outcome, complication rate and reoperation rate, in spite of that PELD surgical group can achieve shorter operation time and hospital stay than OLM surgical group.

Surgery related complications in percutaneous endoscopic lumbar discectomy under local anesthesia

The minimally invasive percutaneous endoscopic discectomy (PED) as the postero-lateral approach with the local anesthesia was started in the late 20th century. The procedure only requires 8 mm of skin incision; thus, it is the least invasive disc surgery presently. The surgery related complications were reviewed in the initial 100 cases from the single surgeon (K. S., first author). Two cases showed exiting nerve irritation, and complained of leg paresthetic pain for 6 to 12 weeks after the surgery (2.0%). The symptoms got better with medicines. One showed post-surgical epidural hematoma, and required surgical removal of the mass (1.0%). Two cases complained neck pain during surgery (2.0%). Surgeons would be aware of the specific complications for the postero-lateral approach of PED procedure.

State-of-the-art management of low back pain in athletes: Instructional lecture

In this paper, we describe "state of the art" on the diagnosis and treatment for low back pain in athletes. Lumbar motion that induces specific pain would be a clue to the exact diagnosis. In the flexion pain group, lumbar herniated nucleus pulposus is the most common disorder. Discogenic pain and type 1 Modic endplate inflammation may also cause flexion pain; however, the diagnosis is sometimes difficult. In children and adolescents, apophyseal ring fracture is prevalent. In the extension pain group, lumbar spondylolysis is very common, especially in pediatric athletes. In adults, facet pain due to overloading would be the pathology, while low back pain with trunk rotation is not common. However, throwing athletes, such as pitchers and hammer throwers, may experience this kind of pain; facet arthritis contralateral to the throwing arm would be the origin of the pain. Low back pain on lumbar lateral bending is rare, but we experienced some cases in golfers in whom type 1 Modic change at the lateral corner was the source of pain. In this article, we explained strategies for state-of-the-art diagnosis and minimally invasive treatment.

Percutaneous biportal endoscopic decompression for lumbar spinal stenosis: a technical note and preliminary clinical results

OBJECTIVE

The use of conventional uniportal spinal endoscopic decompression surgery for lumbar spinal stenosis can be limited by technical difficulties and a restricted field of vision. The purpose of this study is to describe the technique for percutaneous biportal endoscopic decompression (PBED) for lumbar spinal stenosis and analysis of clinical postoperative results.

METHODS

The authors performed a unilateral laminotomy with bilateral foraminal decompression using a unilateral biportal endoscopic system in patients with single-level lumbar stenosis. The authors enrolled only patients who underwent follow-up for longer than 12 months after PBED. Fifty-eight patients were enrolled in this study. This approach was based on 2 portals: one portal was used for continuous irrigation and endoscopic viewing and the other portal was used to manipulate the instruments used in the decompression procedures. Clinical parameters such as the Oswestry Disability Index (ODI), Macnab criteria, and postoperative complications were analyzed.

RESULTS

Neural decompression was effectively performed in all enrolled patients. The mean ODI was significantly lower after PBED. Of 58 patients, 47 (81.0%) had a good or excellent result according to the Macnab criteria. Postoperative ODI and visual analog scale scores were significantly improved compared with preoperative values.

CONCLUSIONS

From a surgical point of view, percutaneous biportal endoscopy is very similar to microscopic spinal surgery, permitting good visualization of the contralateral sublaminar and medial foraminal areas. The authors suggest that the PBED, which is a minimally invasive procedure, is an alternative treatment option for degenerative lumbar stenosis.

Learning Curve of Percutaneous Endoscopic Lumbar Discectomy Based on the Period (Early vs. Late) and Technique (in-and-out vs. in-and-out-and-in): A Retrospective Comparative Study

Objective

To report the learning curve of percutaneous endoscopic lumbar discectomy (PELD) for a surgeon who had not been previously exposed to this procedure based on the period and detailed technique with a retrospective matched comparative design.

Methods

Of 213 patients with lumbar disc herniation encountered during the reference period, 35 patients who were followed up for 1 year after PELD were enrolled in this study. The patients were categorized by the period and technique of operation : group A, the first 15 cases, who underwent by the 'in-and-out' technique; group B, the next 20 cases, who underwent by the 'in-and-out-and-in' technique. The operation time, failure rate, blood loss, complication rate, re-herniation rate, the Visual Analogue Scale (VAS) for back and leg were checked. The alteration of dural sac cross-sectional area (DSCSA) between the preoperative and the postoperative MRI was checked.

Results

Operative time was rapidly reduced in the early phase, and then tapered to a steady state for the 35 cases receiving the PELD. After surgery, VAS scores for the back and leg were decreased significantly in both groups. Complications occurred in 2 patients in group A and 2 patients in group B. Between the two groups, there were significant differences in operative time, improvement of leg VAS, and expansion of DSCSA.

Conclusion

PELD learning curve seems to be acceptable with sufficient preparation. However, because of their high tendency to delayed operation time, operation failure, and re-herniation, caution should be exercised at the early phase of the procedure.

Learning curve of full-endoscopic lumbar discectomy

PURPOSE

To report the learning curve of full-endoscopic lumbar discectomy for a surgeon naive to endoscopic surgery but trained in open microdiscectomy.

METHODS

From July 2006 to July 2009, 57 patients underwent full-endoscopic lumbar discectomy and 66 underwent open microdiscectomy. The clinical results were evaluated with a visual analog scale (VAS) and the Oswestry Disability Index (ODI). Spearman's coefficient of rank correlation (rho) was used to assess the learning curves for the transforaminal and interlaminar procedures of full-endoscopic lumbar discectomy.

RESULTS

After full-endoscopic lumbar discectomy, the VAS and ODI results of the patients followed up were comparable with those of open microdiscectomy. A steep learning curve was observed for the transforaminal procedure, but not the interlaminar procedure.

CONCLUSIONS

The learning curve of the transforaminal approach was steep and easy to learn, while the learning curve of the interlaminar approach was flat and hard to master.