Comparison of the Clinical and Radiological Outcomes of Full-Endoscopic Laminotomy and Conventional Subtotal Laminectomy for Lumbar Spinal Stenosis: A Randomized Controlled Trial.

STUDY DESIGN: Randomized controlled trial. OBJECTIVE: The primary objective of this study was to compare the short-term clinical and radiological outcomes of full-endoscopic lumbar laminotomy (FEL) with those of subtotal lumbar laminectomy (STL) for lumbar spinal stenosis (LSS). METHODS: In this prospective randomized trial a total of 52 patients were enrolled from May 2016 to September 2021 after providing written informed consent. The authors investigated 45 patients who were followed up for more than 6 months. RESULTS: There were significant improvements in visual analogue scale (VAS) and Oswestry Disability Index (ODI) scores after the operation in both groups. The FEL group tended to have significantly shorter hospital stay. Interestingly, a statistically significant increase in postoperative lumbar lordosis and segmental angle was observed in the FEL group and both groups, respectively. Spondylolisthesis was exacerbated or newly developed in five of the 21 patients (24%) in the STL group. In contrast, improvement in spondylolisthesis was observed in two of the 24 patients (8%) in the FEL group. There were no complications that resulted in fatal sequelae and no significant difference in the complication rate. CONCLUSIONS: The clinical results of FEL were similar to those of STL. In addition, the results of FEL were superior to those of STL in terms of a decrease in the postoperative length of stay and radiologic instability, such as iatrogenic spondylolisthesis. The results of this study indicate that FEL is a comparable surgical method to STL for LSS.

Comparative Analysis of 2 Different Types of Titanium Mesh Cage for Single-level Anterior Cervical Corpectomy and Fusion in Terms of Postoperative Subsidence and Sagittal Alignment.

STUDY DESIGN: This was a retrospective observatory analysis study. OBJECTIVE: The objective of this study was to compare the differences in clinical and radiologic outcomes among patients who underwent anterior cervical corpectomy and fusion (ACCF) using titanium mesh cage (TMC) with end-caps and patients who underwent ACCF using TMC without end-cap. SUMMARY OF BACKGROUND DATA: TMC has been widely used as an effective treatment option for ACCF. However, the subsidence of TMC has been observed frequently in the early postoperative period in some cases, resulting in related clinical complications. MATERIALS AND METHODS: Patients who underwent single-level ACCF using TMC from September 2008 to June 2014 at our institute were retrospectively reviewed. Patients treated with TMC with end-cap were classified as an end-cap group, while patients treated with TMC without end-cap classified as a control group. The round press-fit-type end-caps with 2.5-degree angulation were used at both ends of the cage for the end-cap group. Patients were followed postoperatively for a minimum of 36 months with radiologic evaluation. RESULTS: The subsidence was lower in the end-cap group (4.3±3.6 vs. 4.8±3.0, P<0.01), with lower rates of severe subsidence (≥3 mm) than the control group (34.2% vs. 52.1%, P<0.01). Visual analogue scale (VAS) scores for neck pain and Neck Disability Index (NDI) was reported significantly less in the study group, which showed a positive correlation with lesser severe subsidence. Also, the characteristics of subsidence differed between the 2 groups. In the end-cap group, slippage type subsidence occurred, resulting in better sagittal alignment than that in the control group. CONCLUSIONS: For patients undergoing single-level ACCF, using TMC with end-cap provided better clinical results and similar fusion rate, compared with using TMC without end-cap. The end-cap decreased the severity of postoperative subsidence and related neck pain. Also, sagittal alignment was well preserved, suggesting it may contribute to cervical lordosis.

Clinical Characteristics and Outcomes of Patients with Culture-Negative Pyogenic Spondylitis according to Empiric Glycopeptide Use.

BACKGROUND: The optimal choice of antibiotics is challenging in culture-negative pyogenic spondylitis (PS). The empiric use of glycopeptides is suggested depending on various risk factors, although clinical data are sparse. This study aimed to analyze the clinical characteristics and outcomes of patients with culture-negative PS and evaluate the effect of empiric glycopeptide use on clinical outcomes in these patients. MATERIALS AND METHODS: Data on the characteristics, treatment, and outcomes of 175 patients diagnosed with PS were retrospectively obtained from the electronic database of a tertiary referral hospital from 2009 to 2016. Patients with negative culture results were grouped by the duration of glycopeptide treatment: glycopeptide therapy <28 days (Group A) and glycopeptide therapy ≥28 days (Group B). RESULTS: Of 89 patients with negative culture results, 78 were included in the analysis (Group A, n = 66; Group B, n = 12). The mean age of patients with negative culture results was 65.5 years, and 52.6% were male. The median follow-up duration was 573 (interquartile range [IQR], 83 - 1,037) days. The duration of intravenous glycopeptide therapy was 0.0 (IQR, 0.0 - 0.0) days and 55.5 (IQR, 37.0 - 75.7) days for Groups A and B, respectively. Patients who used glycopeptide longer empirically (Group B) had more commonly undergone a previous spinal procedure, including surgery (P = 0.024). The length of hospitalization, erythrocyte sedimentation rate, and C-reactive protein level were significantly higher in Group B compared with those in Group A (P <0.001, P <0.001, and P = 0.006, respectively). Regarding treatment modalities, patients in Group B underwent surgery more frequently (P = 0.017). The duration of parenteral antibiotic treatment was longer in Group B (P <0.001). Recurrence was noted in 7 patients (9.0%), and the recurrence rate was not significantly different between the 2 groups (Group A, 5/66 [7.6%]; Group B, 2/12 [16.7%]; P = 0.293). CONCLUSION: The recurrence rate among patients with culture-negative PS was not different based on the duration of empiric glycopeptide use. However, considering the small sample size and heterogeneity of our study population, we suggest that it is reasonable to administer glycopeptide antibiotics in these patients depending on clinical risk factors. Further large-scale prospective studies are needed to obtain more evidence for appropriate antibiotic treatment.

Accuracy and Safety in Screw Placement in the High Cervical Spine: Retrospective Analysis of O-arm-based Navigation-assisted C1 Lateral Mass and C2 Pedicle Screws.

STUDY DESIGN: This study was a retrospective analysis. OBJECTIVE: The purpose of present study was to evaluate accuracy, efficiency, and safety of intraoperative O-arm-based navigation system for the placement of C1 lateral mass screw (C1LMS) and C2 pedicle screws (C2PSs) in high cervical spine operations. SUMMARY OF BACKGROUND DATA: High screw misplacement rates, various pedicle morphometry and vertebral body size variations have led to a search of image-guided systems to improve the surgical accuracy of screw insertion in high cervical spine. The use of O-arm has been proposed for more accurate and efficient spinal instrumentation. MATERIALS AND METHODS: Between June 2009 and August 2016, a total of 48 patients with atlantoaxial instability were surgically treated using the image-guidance system. To reconstruct atlantoaxial instability, we have been using Harm's technique of C1LMS and C2PS fixations. A frameless, stereotactic O-arm-based image-guidance system was used for correct screw placement. Postoperative computed tomographic scan with multiplanar reconstructions were used to determine the accuracy of the screw placement. RESULTS: A total of 182 screws, including 90 C1LMS and 92 C2PSs were inserted using image-guidance system. In total, 4.4% (4/90) of C1LMS and 7.6% (10/92) of C2PS had cortex violation over 2 mm and considered as "significant." Among the significant cortex violations, "unexpected breech" was 3.3% of all the screws inserted. Two (2.1%) screws inserted had perforated the vertebral artery canal and iatrogenic vertebral artery stenosis was proved with postoperative computed tomography angiography. When divided into time periods, 60% of significant breech occurred during the beginning stage, 40% during adaptation stage and none during expert stage. CONCLUSIONS: In this study, the authors demonstrated that use of image-guidance system seems to be beneficial for high cervical instrumentation which requires much experience and steep learning curves. However, incidence of cortex violation does not disappear completely due to the close proximity to spinal canal and surrounding vessels.

The Clinical Usefulness of Preoperative Imaging Studies to Select Pathologic Level in Cervical Spondylotic Myelopathy: Comparative Analysis of Three-Position MRI and Post-Myelographic CT.

AIM: To compare the accuracy of determining pathologic segment between three-position MRI (3P-MRI) and post-myelographic CT (PMCT) in cervical spondylotic myelopathy (CSM) by assessing the degree of inter-observer and intra-observer agreement. MATERIAL AND METHODS: We retrospectively reviewed 3P-MRI and PMCT for the diagnosis of multilevel CSM in 136 patients who underwent surgery. Using an assessment scale, 8 blind observers with various clinical experiences examined 5 parameters: spinal canal narrowing, foraminal stenosis, bony abnormality, intervertebral disc herniation, and nerve root compression. Spinal canal, neural foraminal, spinal cord and disc protrusion diameters were measured. Intra-observer and inter-observer agreement of each image was analyzed. RESULTS: Spinal canal width and foraminal diameter was found to be significantly smaller in 3P-MRI compared to PMCT. No significant differences of cervical cord diameter and the size of disc protrusion measured in 3P-MRI compared to PMCT were observed. Comparing between 3P-MRI and PMCT, disc abnormality and nerve root compression showed better agreement on 3P-MRI, whereas foraminal stenosis and bony lesion showed better agreement on PMCT. CONCLUSION: In the present study, PMCT was still useful in diagnosis of the foraminal stenosis and bony lesion compared to 3P-MRI but showed limitation in disc abnormality and nerve root compression. Even though PMCT may provide valuable additional information in difficult or ambiguous cases, universal standard of 3P-MRI showed higher reliability in detecting pathologic levels in CSM patients.

Strain behavior of malaligned cervical spine implanted with metal-on-polyethylene, metal-on-metal, and elastomeric artificial disc prostheses - A finite element analysis.

BACKGROUND: Postoperative alterations in cervical spine curvature (i.e. loss of lordotic angle) are frequently observed following total disc replacement surgery. However, it remains unclear whether such changes in lordotic angle are due to preoperative spinal deformities and/or prostheses design limitations. The objective of the study is to investigate strain and segmental biomechanics of the malaligned cervical spine following total disc replacement. METHODS: Three disc prostheses were chosen, namely a metal-on-polyethylene, a metal-on-metal, and an elastomeric prosthesis, which feature different geometrical and material design characteristics. All discs were modelled and implanted into multi-segmental cervical spine finite element model (C3-C7) with normal, straight and kyphotic alignments. Comparative analyses were performed by using a hybrid protocol. FINDINGS: The results indicated that as the spine loses lordotic alignment, the prosthesis with elastomeric core tends to produce significantly larger flexion range of motion (difference up to 6.1°) than metal-on-polyethylene and metal-on-metal prostheses. In contrast, when the treated spine had normal lordotic alignment, the range of motion behaviors of different prostheses are rather similar (difference within 1.9°). Large localized strains up to 84.8% were found with the elastomeric prosthesis, causing a collapsed anterior disc space under flexion loads. INTERPRETATION: Changes in cervical spinal alignments could significantly affect the surgical-level range of motion behaviors following disc arthroplasty; the in situ performance was largely dependent on the designs of the artificial disc devices in particular to the material properties.

Time Course of Radiologic Changes After Lumbar Total Disc Replacement: Experience of Single Institute With Minimum 5-Year Follow-up.

STUDY DESIGN: This was a retrospective observatory analysis study. OBJECTIVE: The purpose of this study was to evaluate long-term safety and therapeutic effectiveness of the lumbar total disc replacement (TDR) using ProDisc-L by analyzing the radiologic changes at the index and adjacent levels in minimum 5-year follow-up. SUMMARY OF BACKGROUND DATA: Early successful clinical results of lumbar TDR have been reported. However, few reports have published its therapeutic effectiveness and radiologic degenerative changes at the index and adjacent segments in the long term. MATERIALS AND METHODS: Forty-three patients were followed-up for at least 60 months. Radiologic changes were assessed by segmental range of motion (ROM) at the index and adjacent levels, global lumbar lordosis, and disc space height (DSH). The magnetic resonance imaging and computed tomographic scans were used to determine the facet arthrosis and intervertebral disc degeneration at the index and adjacent levels. RESULTS: Gradual decrements of DSH restoration were observed until the last follow-up. Mean global and segmental ROM of index segments were significantly reduced (P=0.044, 0.00) at the last visit. There were 21 patients (48.8%) with no motion at index segment (ROM<0.5 degrees) at the last visit. Among the 56 segments operated on, progression of facet arthrosis was observed in 30.3% of index segments and 10.9% of adjacent segments. None of the postoperative radiologic parameters included in the present study presented significant correlation with clinical outcome. CONCLUSIONS: The study demonstrates that only half of the lumbar TDR patients can maintain segmental motion at the index level >5-year after surgery and TDR provides a good clinical outcome postoperatively regardless of motion preservation or DSH height preservation at the last follow-up. After TDR, the degenerative changes in the index and adjacent segments advanced as compared with our previous report of 2-year follow-up, however, these changes did not appear to exert negative influence upon clinical outcomes.

Correction to: Outcomes of oblique lateral interbody fusion for degenerative lumbar disease in patients under or over 65 years of age.

In the original publication of this article [1] is an error in the Results section in the first paragraph in regards to a patient value introduced.

Are Controversial Issues in Cervical Total Disc Replacement Resolved or Unresolved?: A Review of Literature and Recent Updates.

Since the launch of cervical total disc replacement (CTDR) in the early 2000s, many clinical studies have reported better outcomes of CTDR compared to those of anterior cervical discectomy and fusion. However, CTDR is still a new and innovative procedure with limited indications for clinical application in spinal surgery, particularly, for young patients presenting with soft disc herniation with radiculopathy and/or myelopathy. In addition, some controversial issues related to the assessment of clinical outcomes of CTDR remain unresolved. These issues, including surgical outcomes, adjacent segment degeneration (ASD), heterotopic ossification (HO), wear debris and tissue reaction, and multilevel total disc replacement (TDR) and hybrid surgeries are a common concern of spine surgeons and need to be resolved. Among them, the effect of CTDR on patient outcomes and ASD is theoretically and clinically important; however, this issue remains disputable. Additionally, HO, wear debris, multilevel TDR, and hybrid surgery tend to favor CTDR in terms of their effects on outcomes, but the potential of these factors for jeopardizing patients' safety postoperatively and/or to exert harmful effects on surgical outcomes in longer-term follow-up cannot be ignored. Consequently, it is too early to determine the therapeutic efficacy and cost-effectiveness of CTDR and will require considerable time and studies to provide appropriate answers regarding the same. For these reasons, CTDR requires longer-term follow-up data.

Outcomes of oblique lateral interbody fusion for degenerative lumbar disease in patients under or over 65 years of age.

BACKGROUND: Oblique lateral interbody fusion (OLIF) offers the solution to problems of anterior lumbar interbody fusion (ALIF) and lateral lumbar interbody fusion (LLIF). However, OLIF technique for degenerative spinal diseases of elderly patients has been rarely reported. The objective of this study was to determine the clinical and radiological results of OLIF technique for degenerative spinal diseases in patients under or over 65 years of age. METHODS: Sixty-three patients who underwent OLIF procedure were enrolled, including 29 patients who were less than 65 years of age and 34 patients who were over 65 years of age. Fusion rate, change of disc height and lumbar lordotic angle, Numeric Rating Scale (NRS), return to daily activity, patient's satisfaction rate (PSR), and Oswestry disability index (ODI) were used to assess clinical and functional outcomes. RESULTS: The mean NRS scores for back and leg pain decreased, respectively, from 4.6 and 5.9 to 2.3 and 1.8 in the group A (less than 65 years) and from 4.5 and 6.8 to 2.6 and 2.2 in the group B (over 65 years) at the final follow-up period. The mean ODI scores improved from 48.4 to 24.0% in the group A and from 46.5 to 25.2% in the group B at the final follow-up period. In both groups, the NRS and ODI scores significantly changed preoperatively to postoperatively (p <  0.001). However, statistical analysis yielded no significant difference in postoperative NRS/ODI scores between two groups. In both groups, the changes in the disc height, segmental lordosis, and fusion rate between the preoperative and postoperative periods were significant. The amount of change between preoperative and postoperative disc height, segmental lordosis, and whole lumbar lordosis demonstrated significant intergroup differences (p <  0.05). Overall perioperative complications occurred in 8 of 29 (27.6%) patients in the group A and in 10 of 34 (29.4%) patients in the group B. In both groups, the major complication incidence was 0 and 3%, respectively. CONCLUSION: Although there was the slightly high incidence of complication associated with high rate of co-morbidities in elderly patients, OLIF for degenerative lumbar diseases in elderly patients showed favorable clinical and radiological outcomes.

Comparative Study of the Difference of Perioperative Complication and Radiologic Results: MIS-DLIF (Minimally Invasive Direct Lateral Lumbar Interbody Fusion) Versus MIS-OLIF (Minimally Invasive Oblique Lateral Lumbar Interbody Fusion).

STUDY DESIGN: Retrospective observatory analysis. OBJECTIVE: The purpose of this study was to compare the incidence of perioperative complication, difference of cage location, and sagittal alignment between minimally invasive oblique lateral lumbar interbody fusion (MIS-OLIF) and MIS-direct lateral lumbar interbody fusion (DLIF) in the cases of single-level surgery at L4-L5. SUMMARY OF BACKGROUND DATA: MIS-DLIF using tubular retractor has been used for the treatment of lumbar degenerative diseases; however, blunt transpsoas dissection poses a risk of injury to the lumbar plexus. As an alternative, MIS-OLIF uses a window between the prevertebral venous structures and psoas muscle. MATERIALS AND METHODS: A total of 43 consecutive patients who underwent MIS-DLIF or MIS-OLIF for various L4/L5 level pathologies between November 2011 and April 2014 by a single surgeon were retrospectively reviewed. A complication classification based on the relation to surgical procedure and effect duration was used. Perioperative complications until 3-month postoperatively were reviewed for the patients. Radiologic results including the cage location and sagittal alignment were also assessed with plain radiography. RESULTS: There were no significant statistical differences in perioperative parameters and early clinical outcome between 2 groups. Overall, there were 13 (59.1%) approach-related complications in the DLIF group and 3 (14.3%) in the OLIF group. In the DLIF group, 3 (45.6%) were classified as persistent, however, there was no persistent complication in the OLIF group. In the OLIF group, cage is located mostly in the middle 1/3 of vertebral body, significantly increasing posterior disk space height and foraminal height compared with the DLIF group. Global and segmental lumbar lordosis was greater in the DLIF group due to anterior cage position without statistical significance. CONCLUSIONS: In our report of L4/L5 level diseases, the OLIF technique may decrease approach-related perioperative morbidities by eliminating the risk of unwanted muscle and nerve manipulations. Using orthogonal maneuver, cage could be safely placed more posteriorly, resulting in better disk and foraminal height restoration.

Safety of Lateral Interbody Fusion Surgery without Intraoperative Monitoring.

AIM: Oblique lateral interbody fusion (OLIF) is a minimally invasive surgical method that can provide an access to the lumbar spine without direct dissection of psoas muscle and the need for intraoperative neuromonitoring (IOM) is questionable. The aim of this study was to examine and document the transient and persistent perioperative complications in patients who underwent OLIF for degenerative lumbar disease without IOM. MATERIAL AND METHODS: A total of 129 consecutive patients who were diagnosed as degenerative spinal disease from L1 to S1 and underwent mini-open OLIF were identified and retrospectively reviewed. All patients were classified as two groups; non-IOM group and IOM group. According to the relation to surgical procedure, the complications were divided into two groups; "procedurerelated" and "procedure-unrelated". Based on the effect of duration, the complications were defined as "transient" where the symptom is relieved within 30 days postoperatively, and "persistent" where the symptom remains for more than 30 days postoperatively. RESULTS: The study groups comprised 57 cases in the IOM group and 72 in the non-IOM group. The complication rate was 24.6% (transient; 17.6%, persistent; 7.0%) in the IOM group and 29.2% (transient; 25.0%, persistent; 4.2%) in the non-IOM group. The incidence of postoperative leg symptoms related to lumbar plexus and/or psoas muscle injury was 6 transient and 3 persistent in the IOM group (overall 15.3%), and 12 transient and 3 persistent in the non-IOM group (overall 20.9%). CONCLUSION: Mini-open OLIF can be safely carried out without the aid of IOM.

Comparison of Root Images between Post-Myelographic Computed Tomography and Magnetic Resonance Imaging in Patients with Lumbar Radiculopathy.

OBJECTIVE: To evaluate the diagnostic value of computed tomography-myelography (CTM) compared to that of magnetic resonance imaging (MRI) in patients with lumbar radiculopathy. METHODS: The study included 91 patients presenting with radicular leg pain caused by herniated nucleus pulposus or lateral recess stenosis in the lumbar spine. The degree of nerve root compression on MRI and CTM was classified into four grades. The results of each imaging modality as assessed by two different observers were compared. Visual analog scale score for pain and electromyography result were the clinical parameters used to evaluate the relationships between clinical features and nerve root compression grades on both MRI and CTM. These relationships were quantified by calculating the receiver-operating characteristic curves, and the degree of relationship was compared between MRI and CTM. RESULTS: McNemar's test revealed that the two diagnostic modalities did not show diagnostic concurrence (p<0.0001). Electromyography results did not correlate with grades on either MRI or CTM. The visual analog pain scale score results were correlated better with changes of the grades on CTM than those on MRI (p=0.0007). CONCLUSION: The present study demonstrates that CTM could better define the pathology of degenerative lumbar spine diseases with radiculopathy than MRI. CTM can be considered as a useful confirmative diagnostic tool when the exact cause of radicular pain in a patient with lumbar radiculopathy cannot be identified by using MRI. However, the invasiveness and potential complications of CTM are still considered to be pending questions to settle.

Ureter Injury as a Complication of Oblique Lumbar Interbody Fusion.

BACKGROUND: Oblique lumbar interbody fusion is a commonly used surgical method of achieving lumbar interbody fusion. There have been some reports about complications of oblique lumbar interbody fusion at the L2-L3 level. However, to our knowledge, there have been no reports about ureter injury during oblique lumbar interbody fusion. We report a case of ureter injury during oblique lumbar interbody fusion to share our experience. CASE DESCRIPTION: A 78-year-old male patient presented with a history of lower back pain and neurogenic intermittent claudication. He was diagnosed with spinal stenosis at L2-L3, L4-L5 level and spondylolisthesis at L4-L5 level. Symptoms were not improved after several months of medical treatments. Then, oblique lumbar interbody fusion was performed at L2-L3, L4-L5 level. During the surgery, anesthesiologist noticed hematuria. A retrourethrogram was performed immediately by urologist, and ureter injury was found. Ureteroureterostomy and double-J catheter insertion were performed. The patient was discharged 2 weeks after surgery without urologic or neurologic complications. At 2 months after surgery, an intravenous pyelogram was performed, which showed an intact ureter. CONCLUSIONS: Our study shows that a low threshold of suspicion of ureter injury and careful manipulation of retroperitoneal fat can be helpful to prevent ureter injury during oblique lumbar interbody fusion at the upper level.

MRI-based determination of convex or concave surgical approach for lateral lumbar interbody fusion in lumbar degenerative scoliosis: a retrospective radiographic comparative analysis.

BACKGROUND: We determined the optimal approach to perform lateral lumbar interbody fusion (LLIF) to treat lumbar degenerative scoliosis (LDS) by comparing the safe zone and psoas muscle on the concave and convex sides. METHODS: Patients without scoliosis (N.=52) and those with levoscoliosis (N.=55) and dextroscoliosis (N.=53) were included. Vertebral anteroposterior diameter, overlap between the retroperitoneal vessels and the anterior edge of the vertebra, and overlap between the ventral nerve roots and the posterior edge of the vertebra were measured, and safe zones were calculated. The cross-sectional area (CSA) and fatty infiltration (FI) rate of the bilateral psoas muscle were measured, and the convex and concave sides were compared. RESULTS: The ventral overlap on the convex side decreased at the L3-4 and L4-5 levels in the levoscoliosis group (P=0.05 and P=0.01, respectively) and at the L2-3 and L3-4 levels in the dextroscoliosis group (P=0.01 and P=0.03, respectively). The convex side at the L3-4 and L4-5 levels presented a greater safe zone in the levoscoliosis group (76.11% vs. 74.00% at L3-4, P=0.02; 69.37% vs. 63.16% at L4-5, P=0.00). The convex side at the L2-3, L3-4, and L4-5 levels in the dextroscoliosis group showed greater safe zones compared to those in the group without scoliosis (77.78% vs. 74.40% at L2-3, P=0.02; 72.15% vs. 69.87% at L3-4, P=0.03; and 58.45% vs. 54.39% L4-5 level, P=0.01). CSA of the psoas muscle on the concave side was significantly higher at the L2-3 and L3-4 levels (P=0.02 and 0.01, respectively). The psoas muscle on the concave side was significantly thicker (P=0.00 at all levels) with a higher FI rate. CONCLUSIONS: The convex retroperitoneal vessels were positioned more anteriorly, whereas the ventral nerve roots lacked significant positional alterations, increasing the convex safe zone and providing optimal disc space access and less psoas muscle injury.

Transforaminal Percutaneous Endoscopic Lumbar Diskectomy with Percutaneous Epidural Neuroplasty in Lumbar Disk Herniation: Technical Note.

OBJECTIVE: Percutaneous endoscopic lumbar diskectomy and percutaneous epidural neuroplasty is a commonly used minimally invasive spinal surgery in lumbar disk herniation. But to our knowledge, there is no report about the results of percutaneous endoscopic lumbar diskectomy with percutaneous epidural neuroplasty. We did this study to evaluate the effect of percutaneous endoscopic lumbar diskectomy with percutaneous epidural neuroplasty in lumbar disk herniation. METHODS: We report a series of cases about techniques and results of percutaneous endoscopic lumbar diskectomy with percutaneous epidural neuroplasty in lumbar disk herniation, as well as introduce technical procedures and advantages. RESULTS: Seven patients improved axial back pain with percutaneous endoscopic lumbar diskectomy with percutaneous epidural neuroplasty and had no complications. The percutaneous endoscopic lumbar diskectomy with percutaneous epidural neuroplasty has many advantages with removing lumbar disk herniation in procedures. CONCLUSIONS: Percutaneous endoscopic lumbar diskectomy with percutaneous epidural neuroplasty is a safe and effective surgical method in lumbar disk herniation.

Surgical Outcomes of Anterior Cervical Fusion Using Deminaralized Bone Matrix as Stand-Alone Graft Material: Single Arm, Pilot Study.

OBJECTIVE: To investigate the safety and efficacy of demineralized bone matrix (DBM) as a bone graft substitute for anterior cervical discectomy and fusion (ACDF) surgery. METHODS: Twenty consecutive patients treated with ACDF using stand-alone polyestheretherketone (PEEK) cages (Zero-P) with DBM(CGDBM100) were prospectively evaluated with a minimum of 6 months of follow-up. Radiologic efficacy was evaluated with a 6-point scoring method for osseous fusion using plain radiograph and computed tomogrpahy scans. Clinical efficacy was evaluated using the visual analogue scale (VAS), Owestry disability index (ODI), and short-form health questionnaire-36. The safety of the bone graft substitute was assessed with vital sign monitoring and a survey measuring complications at each follow-up visit. RESULTS: There were significant improvements in VAS and ODI scores at a mean 6-month follow-up. Six months after surgery, solid fusion was achieved in all patients. Mean score on the 6-point scoring system was 5.1, and bony formation was found to score at least 4 points in all patients. There was no case with implant-related complications such as cage failure or migration, and no complications associated with the use of CGDBM100. CONCLUSION: ACDF using CGDBM100 demonstrated good clinical and radiologic outcomes. The fusion rate was comparable with the published results of traditional ACDF. Therefore, the results of this study suggest that the use of a PEEK cage packed with DBM for ACDF is a safe and effective alternative to the gold standard of autologous iliac bone graft.

Minimally Invasive Transforaminal Lumbar Interbody Fusion at L5-S1 through a Unilateral Approach: Technical Feasibility and Outcomes.

Background. Minimally invasive spinal transforaminal lumbar interbody fusion (MIS-TLIF) at L5-S1 is technically more demanding than it is at other levels because of the anatomical and biomechanical traits. Objective. To determine the clinical and radiological outcomes of MIS-TLIF for treatment of single-level spinal stenosis low-grade isthmic or degenerative spondylolisthesis at L5-S1. Methods. Radiological data and electronic medical records of patients who underwent MIS-TLIF between May 2012 and December 2014 were reviewed. Fusion rate, cage position, disc height (DH), disc angle (DA), disc slope angle, segmental lordotic angle (SLA), lumbar lordotic angle (LLA), and pelvic parameters were assessed. For functional assessment, the visual analogue scale (VAS), Oswestry disability index (ODI), and patient satisfaction rate (PSR) were utilized. Results. A total of 21 levels in 21 patients were studied. DH, DA, SLA, and LLA had increased from their preoperative measures at the final follow-up. Fusion rate was 86.7% (18/21) at 12 months' follow-up. The most common cage position was anteromedial (15/21). The mean VAS scores for back and leg pain mean ODI scores improved significantly at the final follow-up. PSR was 88%. Cage subsidence was observed in 33.3% (7/21). Conclusions. The clinical and radiologic outcomes after MIS-TLIF at L5-S1 in patients with spinal stenosis or spondylolisthesis are generally favorable.

Minimally Invasive TLIF Using Unilateral Approach and Single Cage at Single Level in Patients over 65.

Background. Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) is a widely accepted surgical procedure. But there are only a few reports of MIS-TLIF using the unilateral approach and single cage in elderly patients. Objective. The study investigated the clinical and radiological outcomes of MIS-TLIF using the unilateral approach and single cage in the patients over 65 years of age. Methods. Thirty-eight patients were followed for a mean of 15.5 ± 11.61 months. Radiological data include fusion rate, change of disc height, and central canal area. The numeric rating scale (NRS) and Oswestry disability index (ODI) were used to assess clinical outcomes. Results. The mean age of these patients at operation was 71.82 ± 4.71 years (range, 65-82 years). Evidence of fusion was observed radiologically in 64.71% at 6 months and 87.5% at 12 months after surgery, giving a final fusion rate of 100%. The mean NRS scores for back and leg pain and ODI scores improved significantly at the final follow-up. Conclusions. Clinical and radiologic outcomes of MIS-TLIF using unilateral approach and single cage in elderly patients indicate an acceptable method for the treatment of various kinds of lumbar spinal diseases.

Endoscopic Radiofrequency Ablation of the Sacroiliac Joint Complex in the Treatment of Chronic Low Back Pain: A Preliminary Study of Feasibility and Efficacy of a Novel Technique.

Background. Radiofrequency ablation (RFA) is a less invasive technique for treatment of sacroiliac joint (SIJ) pain. Objective. To evaluate the feasibility and efficacy of endoscope-guided RFA for the treatment of CLBP from the SIJ complex. Methods. In this retrospective study, the medical records of 17 patients who underwent endoscope-guided RFA of the SIJ complex were reviewed. A bipolar radiofrequency probe was used to lesion the posterior capsule of the SIJ as well as the lateral branches of S1, S2, S3, and the L5 dorsal ramus in multiple locations. We visualized the ablation area using endoscope. We assessed visual analogue scale (VAS) and the Oswestry disability index (ODI) preoperatively, immediately postop, and at 1-, 3-, and 6-month postop outpatient clinic visits. Patient satisfaction of the procedure was assessed in percentages. Results. The mean duration of operation was 20 to 50 minutes. The mean VAS and the ODI scores decreased significantly immediately after the procedure and were kept significantly lower than baseline levels during the follow-up periods. No complications occurred perioperatively and during the follow-up periods. 88.6% of patients were satisfied with the procedure. Conclusions. Our preliminary results suggest that endoscope-guided RFA may be alternative option to treat CLBP secondary to SIJ complex.