Comparative study of the efficacy and safety of minimally invasive interlaminar full-endoscopic discectomy versus conventional microscopic discectomy in single-level lumbar herniated intervertebral disc (ENDO-F Trial): a multicenter, prospective, randomized controlled trial protocol

Background

Advances in minimally invasive surgery have expanded the indications for interlaminar full-endoscopic discectomy. Although the clinical outcomes for this approach may be equivalent to those of conventional microscopic discectomy, the supporting evidence is still based on small, single-center, prospective, and retrospective studies. Therefore, a multicenter randomized controlled trial is warranted.

Methods

This will be a prospective, multicenter, randomized controlled trial comparing the efficacy and safety of interlaminar full-endoscopic discectomy to those of conventional microscopic discectomy. The trial will enroll 100 participants with a lumbar disc herniation, 50 in each group. The primary outcome will be the Oswestry Disability Index (ODI) score at 12 months post-surgery. Secondary outcomes will be back and leg pain (visual analog scale); the ODI; the EuroQol-5-dimension score; patient satisfaction; and walking distance/time and time to return to daily activities post-surgery. Surgical outcomes will include postoperative drainage, operative time, duration of hospital stay, postoperative creatine kinase level as an indicator of muscle injury, and postoperative scarring. Postoperative magnetic resonance imaging, computed tomography, and simple radiography will be performed to evaluate radiographic outcomes between the two surgical approaches. Surgery-related complications and adverse effects will be evaluated as safety outcomes. A single assessor at each participating hospital, blinded to group allocation, will assess the enrolled participants at baseline, at 2 weeks, and at 3, 6, and 12 months postoperatively.

Discussion

This trial is designed to determine whether interlaminar full-endoscopic discectomy is clinically comparable to microscopic discectomy to treat lumbar disc herniations. All efforts will be made to reduce bias, including adequate sample size, blinded analyses, and multicenter prospective registration. The outcomes will inform practice, providing the evidence needed for using interlaminar full-endoscopic over microscopic discectomy by confirming the potential of this technique to improve patient satisfaction and clinical outcomes.

Trial registration: Clinical Research Information Service; cris.nih.go.kr. (KCT0006277); protocol version (v1, June 8, 2021).

Endoscopic Spine Surgery of the Cervicothoracic Spine: A Review of Current Applications

BACKGROUND

Endoscopic spine surgery in the cervicothoracic spine is generating continued interest in a rapidly evolving field. The authors present 4 techniques for fully endoscopic cervical spine surgery: (1) posterior cervical unilateral laminectomy and bilateral decompression, (2) posterior cervical foraminotomy, (3) anterior cervical discectomy, and (4) anterior transcorporal discectomy. Two techniques for fully endoscopic thoracic spine surgery are also presented: (1) posterior thoracic unilateral laminectomy and bilateral decompression and (2) transforaminal thoracic endoscopic discectomy and foraminotomy.

METHODS

We describe 6 different surgical approaches and review the relevant literature about each technique.

RESULTS

The clinical application of endoscopic spine surgery techniques has evolved over the past 40 years. Recent data suggest comparable outcomes to other procedures and perhaps fewer complications and quicker recovery when these techniques are used in the cervical and thoracic spine. Significant variability exists in these approaches depending on the goal of canal decompression, root decompression, and the site of the pathology.

CONCLUSIONS

Each endoscopic approach in the cervicothoracic spine has its technical nuances, outcomes, advantages, and disadvantages, making fully endoscopic cervicothoracic spine surgery an exciting and growing field.

Correlation of Paraspinal Muscle Mass With Decompensation of Sagittal Adult Spinal Deformity After Setting of Fatigue Post 10-Minute Walk

OBJECTIVE

The purpose of this study was to investigate the changes in spinopelvic parameters before and after the setting of muscle fatigue along with its correlation with pre-existing paraspinal and psoas muscle mass.

METHODS

Single-center retrospective review of prospectively collected data was conducted on 145-adults with symptomatic loss of lumbar lordosis (LL). Radiographs were taken before and after walking for 10 minutes. Magnetic resonance imaging was used to calculate paraspinal muscle (PSM) cross-sectional area (CSA), mean signal intensity, fatty infiltration (FI), and lean muscle mass at thoracolumbar junction (T12) and lower lumbar level (L4). Psoas CSA was calculated at L3. Patients were divided into 2 groups namely compensated sagittal deformity (CSD) (SVA ≤ 4 cm, PT > 20°) and decompensated sagittal deformity (DSD) (SVA > 4 cm, PT > 20°) based on prewalk measurements.

RESULTS

Initial mean SVA was 1.8 cm and 11 cm for CSD and DSD respectively (p < 0.01). After walking, significant deteriorations in SVA, PT-LL (p < 0.01) were observed in CSD without significant change in thoracic kyphosis (TK). All sagittal parameters in DSD deteriorated significantly. DSD group had significantly poorer PSM quality at T12 and L4 compared to CSD group. In CSD group, sagittal decompensation correlated with muscle quality, i.e. , decreases in LL (ΔLL) correlated with CSA of PSM/vertebral body (VB) at L4 (r = -0.412, p = 0.046) while increases in TK (ΔTK) correlated with CSA of PSM/VB at T12 (r = 0.477, p = 0.018). ΔSVA and ΔPT correlated with FI at L4 (r = 0.577, p = 0.003 and r = -0.407, p = 0.048, respectively). DSD group, had weak correlations (-0.3 < r < -0.1) between changes in sagittal and PSM parameters.

CONCLUSION

PSM quality in adults with spinal deformity correlates with patients' ability to maintain an upright posture and sagittal decompensation after walking for 10 minutes.

Transumbilical Retroperitoneal Lumbar Interbody Fusion: A Technical Note and Preliminary Case Series

OBJECTIVE

Anterior lumbar interbody fusion (ALIF) has advantages over posterior lumbar interbody fusion or transforaminal lumbar interbody fusion techniques in that it minimizes damage to the anatomical structure of the posterior spinal segment and enables indirect decompression of the foramen by insertion of a tall cage. However, the predominant abdominal scar tissue reduces patients' satisfaction after ALIF. Herein, we describe the technique of transumbilical lumbar interbody fusion (TULIF) and its preliminary results in a case series.

METHODS

A retrospective review of 154 consecutive patients who underwent TULIF between the L2-3 and L4-5 levels was performed. After preoperatively selecting patients by evaluating the location of the umbilicus and vessel anatomy, a vertical skin incision was made on the umbilicus to minimize the abdominal scar tissue.

RESULTS

There were 120 single-level (110 L4-5 and 10 L3-4), 31 two-level, and 3 three-level surgeries. All patients were very satisfied with their postoperative abdominal scars, which were noticeably faint compared to those after conventional ALIF.

CONCLUSION

TULIF is a feasible, minimally invasive surgical option that can achieve both the treatment of degenerative spinal disease and satisfactory cosmesis. Although it is technically demanding, patients obtain sufficient benefits.

Spinal subdural hematoma after interlaminar full-endoscopic decompression of lumbar spinal stenosis: a case report and literature review

The use of full-endoscopic decompression for lumbar spinal stenosis has been increasing recently. It is a minimally invasive surgical procedure that has few complications. Spinal subdural hematoma (SSH) following endoscopic surgery has never been reported. Previously described SSHs have occurred spontaneously or due to surgery-related iatrogenic injury. We describe the first case of SSH after endoscopic decompression. A 68-year-old woman presented with bilateral radiating pain and neurological claudication due to lumbar spinal stenosis at the L4-5 level. Full-endoscopic interlaminar decompression was performed without intraoperative complications. Preoperative leg pain improved after endoscopic decompression. However, two days after the index surgery, the patient complained of severe radiating pain in her right leg with urinary retention. The radiologic evaluation showed compressive subdural fluid collection at the index level. Open microscopic decompression was performed. No dural injury was observed. After durotomy, xanthochromic fluid gushed out at a high pressure. We found that the arachnoid was also intact. The patient recovered completely after surgical hematoma evacuation. Although SSH after endoscopic decompression is a very rare event, it is a reminder that suspicion and urgent imaging and intervention are necessary during the postoperative period upon development of unexpected, progressive neurological deterioration regardless of intraoperative problems. Additionally, early surgical decompression is necessary for optimal neurological recovery.

Long-term clinical and radiological follow-up after anterior endoscopic cervical discectomy: a case report

Anterior endoscopic cervical discectomy (AECD) using laser and micro forceps for cervical intervertebral disc herniation has been considered as an effective treatment modality in selected cases. However, several spine surgeons are concerned about the adverse outcomes of discectomy without fusion, such as postoperative instability, disc space narrowing, and segmental kyphosis. We report two cases of AECD that was performed 19 and 21 years ago. First case was a 44-year-old female with C56 cervical soft disc rupture and second case was a 42-year-old male with C67 cervical soft disc rupture. These patients suffered from cervical intervertebral disc herniation and underwent AECD. The surgical method followed the general AECD method that removed selectively-ruptured particle only. In both cases, the symptoms improved after AECD, and these patients did not experience any problems until recently. Good clinical results have been shown over the long-term, as seen in the two cases described here. In the radiological evaluation, it was confirmed that the postoperative level was stable and disc height was preserved. Furthermore, sagittal alignment and segmental motion of the cervical vertebra were both maintained. In these two cases, disc height was insignificantly different before and after surgery over a long period. Thus, AECD provides good results, even in long-term follow-up, without acceleration of disc degeneration.

Transthoracic microsurgical anterior decompression without fusion for ossification of the posterior longitudinal ligament in the thoracic spine

OBJECTIVE

The authors aimed to analyze outcomes following transthoracic microsurgical anterior decompression of thoracic ossification of the posterior longitudinal ligament (T-OPLL), which was causing myelopathy, and determine the predictive factors for surgical outcomes.

METHODS

Patients who underwent transthoracic microsurgical anterior decompression without fusion for the treatment of T-OPLL from December 2014 to May 2019 were included. Demographic, radiological, and perioperative data and clinical outcomes of 35 patients were analyzed. The modified Japanese Orthopaedic Association (mJOA) score and recovery rate were used to evaluate functional outcomes.

RESULTS

A total of 35 consecutive patients (8 men and 27 women; mean age 52.2 ± 10.8 years) were enrolled in this study, and the mean follow-up period was 65.5 ± 51.9 months. The mean mJOA score significantly improved after surgery (5.9 ± 1.8 vs 8.3 ± 1.5, p < 0.001), with a mean recovery rate of 47.7% ± 24.5%. The visual analog scale (VAS) score significantly improved after surgery (7.3 ± 1.3 vs 4.3 ± 0.7, p < 0.001). The outcome was excellent in 4 patients (11.4%), good in 21 patients (60.0%), fair in 4 patients (11.4%), unchanged in 5 patients (14.3%), and worsened in 1 patient (2.9%). There were 12 cases of CSF leakage, 1 case of epidural hematoma, 1 case of pleural effusion, and 1 case of pneumothorax. Age, preoperative kyphotic angle, anteroposterior length of T-OPLL at the maximally affected level, and mass occupying rate were identified as predictors associated with postoperative outcome. A multivariate regression analysis revealed that age and preoperative kyphotic angle were independent risk factors for postoperative outcomes.

CONCLUSIONS

Transthoracic microsurgical anterior decompression without fusion achieved favorable clinical and radiological outcomes for treating T-OPLL with myelopathy. Patient age and preoperative kyphotic angle were independent risk factors for lower recovery rate.

Transforaminal endoscopic thoracic discectomy with foraminoplasty for the treatment of thoracic disc herniation

Background

Symptomatic thoracic disc herniation (TDH) is a rare clinical entity and surgical intervention for it is even more uncommon. Despite several surgical techniques being described for thoracic discectomy, considering the unique surgical challenges, none of them have been accepted universally. Minimally invasive techniques have brought in a paradigm shift in the management of cervical/lumbar spinal disorders and similar techniques have been extrapolated to the thoracic region too. The purpose of this paper is to describe our technique, surgical experience, and the clinical results of transforaminal endoscopic thoracic discectomy (TETD).

Methods

Consecutive patients who underwent TETD (2001-2018) were reviewed. Patients who had a minimum of 6 months of follow-up, and without cervical and lumbar spine surgery or trauma during the follow-up period were included in the study. TETD was performed in patients who presented with symptomatic disc herniation of the thoracic spine and did not respond to conservative treatments. Patients with calcified disc herniation or concomitant ossification of the posterior longitudinal ligament (OPLL) were excluded. Under local anesthesia and intravenous sedation, a 4.7-mm endoscope (TESSYS, Joimax GmbH, Germany) was introduced via transforaminal approach with foraminoplasty using reamer. Patient outcome was evaluated using visual analogue scale (VAS) and Oswestry disability index (ODI) scores. Patient satisfaction was measured using Macnab's criteria.

Results

Ninety-two consecutive patients (mean age was 48.9 years, 57 males) who underwent TETD from 2001 to 2018 met the inclusion criteria. Patients underwent surgery at different levels: 16 patients for T2-3 to T5-6 level, 41 cases for T6-7 to T8-9, and 35 patients for T9-10 to T12-L1. During follow-up for an average of 38.4 months, all patients showed a significant improvement of pain (7.6 to 1.6 in VAS and 68.2 vs. 13.2 for ODI, P<0.05 for both). There was one patient who had transient motor weakness.

Conclusions

TETD for soft, paramedian or lateral symptomatic TDH is a feasible and effective minimally invasive treatment option with favorable clinical results.

Probiotic effects of mixture of Groenewaldozyma salmanticensis and Gluconacetobacter liquefaciens on growth and immune responses in Paralichthys olivaceus

This study was performed to evaluate the effects of dietary probiotics on growth, non-specific immune responses and disease resistance in olive flounder, Paralichthys olivaceus. During 8 weeks, the fish were fed the five experimental diets such as a basal commercial diet (CON), oxytetracycline (OTC) and three basal diets containing Bacillus subtilis (BS), a commercial microbial product (CES) and a mixture of yeast and bacterium (PI), respectively. Fish fed all the probiotics diets and OTC showed a significantly higher growth than fish-fed CON (P < 0·05). Fish-fed PI had a significantly higher nitroblue tetrazolium activity, whereas fish-fed CES showed a higher lysozyme level (P < 0·05). A 7-day challenge test also showed that fish-fed PI had a cumulative survival rate equivalent to that of fish-fed OTC (P < 0·05). Moreover, the diet (PI) appeared to increase the diversity of microbial community in the fish. All these results suggest that the probiotics diet could function as a potential antibiotic replacer in the olive flounder. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is unique in revealing that a diet mixture of yeast, Groenewaldozyma salmanticensis and bacterium Gluconacetobacter liquefaciens can enhance growth, innate immunity and diversity of microbial community including dominant species in the olive flounder. All these indicate that the diet mixture could function as a potential antibiotic replacer in one of the most commercially important fisheries in South Korea.

Interspinous endoscopic lumbar decompression: technical note

Lumbar stenosis is a very common degenerative spine condition that can result in radicular and claudication symptoms. Here we describe our experience with a novel midline interspinous process endoscopic decompression procedure that can be performed in awake patients as an outpatient procedure. An interspinous endoscopic lumbar laminectomy and bilateral foraminotomy technique is presented here. A step-by-step technique for accessing the lumbar central canal and bilateral foramina from a midline interspinous approach is presented. A Jamshidi needle, reamers, and side shaving manual drill are used to create an access channel for a 11.5 mm outer diameter tubular retractor. The Joimax rigid laminoscope with a 10 mm diameter and 6 mm working channel was then used to visualize the decompression procedure. The unique technical steps presented here make it possible to safely insert a 11.5 mm outer diameter tubular retractor for a "large" working channel endoscope. The procedure is so minimally invasive, it can be performed with the patient awake.

Brown-Séquard Syndrome Caused by Acute Traumatic Cervical Disc Herniation

Brown-Séquard syndrome (BSS) is an incomplete spinal cord injury caused by damage to one-half of the spinal cord. Most cases of BSS result from penetrating trauma or tumors, and acute cervical disc herniation is a relatively rare cause of BSS. In this case, a 34-year-old man with a sudden onset posterior neck pain and left side motor weakness was admitted to the local spine hospital. Pain and temperature sensation of pain was decreased below the right C4 dermatome. The left arm and leg motor grade was 0. Magnetic resonance imaging (MRI) showed a huge trans-ligamentous herniated disc rupture from the center to the left at the level of C3-4, and anterior cervical discectomy and fusion were performed. After emergency surgery, left arm and leg motor grade recovered to 2, and normal voiding function returned. MRI verified complete removal of the cervical herniated disc. This case describes the approach to rapid diagnosis in a patient with characteristic clinical symptoms of BSS and radiological findings of a herniated cervical disc. Rapid and accurate diagnosis and immediate decompressive surgery increased the possibility of a good surgical outcome, even if the neurologic deficits are grave at the time of admission.

Percutaneous Endoscopic Thoracic Discectomy in the Upper and Midthoracic Spine: A Technical Note

Despite the successful application of percutaneous endoscopic thoracic discectomy (PETD), its technical feasibility and outcomes for symptomatic upper and midthoracic disc herniation have not been reported yet. The purpose of this article was to evaluate the feasibility of the percutaneous transforaminal endoscopic approach to remove disc herniations in the upper and midthoracic spine. Fourteen consecutive patients (mean age, 42.4 years; 12 males, 2 females) who underwent PETD were included in the analysis. The procedure was performed under local anesthesia and intravenous sedation using the standard endoscopy instrument set. The transforaminal approach combined with foraminoplasty was used to access the herniated areas. Treatment outcomes were evaluated using visual analogue scale (VAS) scores, Oswestry Disability Index (ODI) scores, and the modified MacNab criteria. Four discectomies were performed at T2–3, 5 at T3–4, and 5 at T5–6. The mean follow-up period was 43.4 months, and all patients showed statistically significant postoperative improvement (VAS: 7.3 to 2.3, ODI: 53.5 to 16.9, p<0.05 for all). No serious complications were reported during follow-up. PETD for upper and midthoracic disc herniation is a feasible and effective minimally invasive treatment option with favorable clinical results.