[Protective mechanism of salvianolic acid B on blood vessels].

Salvianolic acid B(Sal B) is the main water-soluble component of Salvia miltiorrhiza Bunge. Studies have found that Sal B has a good protective effect on blood vessels. Sal B can protect endothelial cells by anti-oxidative stress, inducing autophagy, inhibiting endoplasmic reticulum stress(ERS), inhibiting endothelial inflammation and adhesion molecule expression, inhibiting endothelial cell permeability, anti-thrombosis, and other ways. In addition, Sal B can alleviate endothelial cell damage caused by high glucose(HG). For vascular smooth muscle cell(VSMC), Sal B can reduce the synthesis and secretion of inflammatory factors by inhibiting cyclooxygenase. It can also play a vasodilatory role by inhibiting Ca~(2+) influx. In addition, Sal B can inhibit VSMC proliferation and migration, thereby alleviating vascular stenosis. Sal B also inhibits lipid deposition in the subendothelium, inhibits macrophage conversion to foam cells, and reduces macrophage apoptosis, thereby reducing the volume of subendothelial lipid plaques. For some atherosclerosis(AS) complications, such as peripheral artery disease(PAD), Sal B can promote angiogenesis, thereby improving ischemia. It should be pointed out that the conclusions obtained from different experiments are not completely consistent, which needs further research. In addition, previous pharmacokinetics showed that Sal B was poorly absorbed by oral administration, and it was unstable in the stomach, with a large first-pass effect in the liver. Sal B had fast distribution and metabolism in vivo and short drug action time. These affect the bioavailability and biological effects of Sal B, and the development of clinically valuable Sal B non-injectable delivery systems remains a great challenge.

[Protective mechanism of tetramethylpyrazine on cardiovascular system].

Tetramethylpyrazine is the main component of Ligusticum chuanxiong. Studies have found that tetramethylpyrazine has a good protective effect against cardiovascular diseases. In the heart, tetramethylpyrazine can reduce myocardial ischemia/reperfusion injury by inhibiting oxidative stress, regulating autophagy, and inhibiting cardiomyocyte apoptosis. Tetramethylpyrazine can also reduce the damage of cardiomyocytes caused by inflammation, relieve the fibrosis and hypertrophy of cardiomyocytes in infarcted myocardium, and inhibit the expansion of the cardiac cavity after myocardial infarction. In addition, tetramethylpyrazine also has a protective effect on the improvement of familial dilated cardiomyopathy. Besides, the mechanisms of tetramethylpyrazine on blood vessels are more abundant. It can inhibit endothelial cell apoptosis by reducing oxidative stress, maintain vascular endothelial function and homeostasis by inhibiting inflammation and glycocalyx degradation, and protect vascular endothelial cells by reducing iron overload. Tetramethylpyrazine also has a certain inhibitory effect on thrombosis. It can play an anti-thrombotic effect by reducing inflammatory factors and adhesion molecules, inhibiting platelet aggregation, and suppressing the expression of fibrinogen and von Willebrand factor. In addition, tetramethylpyrazine can also reduce the level of blood lipid in apolipoprotein E-deficient mice, inhibit the subcutaneous deposition of lipids, inhibit the transformation of macrophages into foam cells, and inhibit the proliferation and migration of vascular smooth muscle cells, thereby reducing the formation of atherosclerotic plaque. In combination with network pharmacology, the protective mechanism of tetramethylpyrazine on the cardiovascular system may be mainly achieved through the regulation of phosphatidylinositol 3 kinase/protein kinase B(PI3K/Akt), hypoxia-inducible factor 1(HIF-1), and mitogen-activated protein kinase(MAPK) pathways. Tetramethylpyrazine hydrochloride and sodium chloride injection has been approved for clinical application, but some adverse reactions have been found in clinical application, which need to be paid attention to.

Protective mechanism of tetramethylpyrazine on cardiovascular system / 中国中药杂志

Tetramethylpyrazine is the main component of Ligusticum chuanxiong. Studies have found that tetramethylpyrazine has a good protective effect against cardiovascular diseases. In the heart, tetramethylpyrazine can reduce myocardial ischemia/reperfusion injury by inhibiting oxidative stress, regulating autophagy, and inhibiting cardiomyocyte apoptosis. Tetramethylpyrazine can also reduce the damage of cardiomyocytes caused by inflammation, relieve the fibrosis and hypertrophy of cardiomyocytes in infarcted myocardium, and inhibit the expansion of the cardiac cavity after myocardial infarction. In addition, tetramethylpyrazine also has a protective effect on the improvement of familial dilated cardiomyopathy. Besides, the mechanisms of tetramethylpyrazine on blood vessels are more abundant. It can inhibit endothelial cell apoptosis by reducing oxidative stress, maintain vascular endothelial function and homeostasis by inhibiting inflammation and glycocalyx degradation, and protect vascular endothelial cells by reducing iron overload. Tetramethylpyrazine also has a certain inhibitory effect on thrombosis. It can play an anti-thrombotic effect by reducing inflammatory factors and adhesion molecules, inhibiting platelet aggregation, and suppressing the expression of fibrinogen and von Willebrand factor. In addition, tetramethylpyrazine can also reduce the level of blood lipid in apolipoprotein E-deficient mice, inhibit the subcutaneous deposition of lipids, inhibit the transformation of macrophages into foam cells, and inhibit the proliferation and migration of vascular smooth muscle cells, thereby reducing the formation of atherosclerotic plaque. In combination with network pharmacology, the protective mechanism of tetramethylpyrazine on the cardiovascular system may be mainly achieved through the regulation of phosphatidylinositol 3 kinase/protein kinase B(PI3K/Akt), hypoxia-inducible factor 1(HIF-1), and mitogen-activated protein kinase(MAPK) pathways. Tetramethylpyrazine hydrochloride and sodium chloride injection has been approved for clinical application, but some adverse reactions have been found in clinical application, which need to be paid attention to.

Protective mechanism of salvianolic acid B on blood vessels / 中国中药杂志

Salvianolic acid B(Sal B) is the main water-soluble component of Salvia miltiorrhiza Bunge. Studies have found that Sal B has a good protective effect on blood vessels. Sal B can protect endothelial cells by anti-oxidative stress, inducing autophagy, inhibiting endoplasmic reticulum stress(ERS), inhibiting endothelial inflammation and adhesion molecule expression, inhibiting endothelial cell permeability, anti-thrombosis, and other ways. In addition, Sal B can alleviate endothelial cell damage caused by high glucose(HG). For vascular smooth muscle cell(VSMC), Sal B can reduce the synthesis and secretion of inflammatory factors by inhibiting cyclooxygenase. It can also play a vasodilatory role by inhibiting Ca~(2+) influx. In addition, Sal B can inhibit VSMC proliferation and migration, thereby alleviating vascular stenosis. Sal B also inhibits lipid deposition in the subendothelium, inhibits macrophage conversion to foam cells, and reduces macrophage apoptosis, thereby reducing the volume of subendothelial lipid plaques. For some atherosclerosis(AS) complications, such as peripheral artery disease(PAD), Sal B can promote angiogenesis, thereby improving ischemia. It should be pointed out that the conclusions obtained from different experiments are not completely consistent, which needs further research. In addition, previous pharmacokinetics showed that Sal B was poorly absorbed by oral administration, and it was unstable in the stomach, with a large first-pass effect in the liver. Sal B had fast distribution and metabolism in vivo and short drug action time. These affect the bioavailability and biological effects of Sal B, and the development of clinically valuable Sal B non-injectable delivery systems remains a great challenge.

ProDisc-C versus anterior cervical discectomy and fusion for the surgical treatment of symptomatic cervical disc disease: two-year outcomes of Asian prospective randomized controlled multicentre study.

PURPOSE: Our study aimed to evaluate non-inferiority of ProDisc-C to anterior cervical discectomy and fusion (ACDF) in terms of clinical outcomes and incidence of adjacent segment disease (ASD) at 24-months post-surgery in Asian patients with symptomatic cervical disc disease (SCDD). METHODS: This multicentre, prospective, randomized controlled trial was initiated after ethics committee approval at nine centres (China/Hong Kong/Korea/Singapore/Taiwan). Patients with single-level SCDD involving C3-C7-vertebral segments were randomized (2:1) into: group-A treated with ProDisc-C and group-B with ACDF. Assessments were conducted at baseline, 6-weeks, 3/6/12/18/24-months post-surgery and annually thereafter till 84-months. Primary endpoint was overall success at 24-months, defined as composite of: (1) ≥ 20% improvement in neck disability index (NDI); (2) maintained/improved neurologic parameters; (3) no implant removal/revision/re-operation at index level; and (4) no adverse/severe/life-threatening events. RESULTS: Of 120 patients (80ProDisc-C,40ACDF), 76 and 37 were treated as per protocol (PP). Overall success (PP) was 76.5% in group-A and 81.8% in group-B at 24-months (p = 0.12), indicating no clear non-inferiority of ProDisc-C to ACDF. Secondary outcomes improved for both groups with no significant inter-group differences. Occurrence of ASD was higher in group-B with no significant between-group differences. Range of motion (ROM) was sustained with ProDisc-C but lost with ACDF at 24-months. CONCLUSION: Cervical TDR with ProDisc-C is feasible, safe, and effective for treatment of SCDD in Asians. No clear non-inferiority was demonstrated between ProDisc-C and ACDF. However, patients treated with ProDisc-C demonstrated significant improvement in NDI, neurologic success, pain scores, and 36-item-short-form survey, along with ROM preservation at 24-months. Enrolment difficulties resulted in inability to achieve pre-planned sample size to prove non-inferiority. Future Asian-focused, large-scale studies are needed to establish unbiased efficacy of ProDisc-C to ACDF.

Expression signature of inflammation-associated long non-coding RNAs in adult-onset Still's disease.

OBJECTIVES: Adult-onset Still's disease (AOSD) is a rare and complex inflammatory disease with unclear immunopathogenesis. This study aims to investigate the expression signature of inflammation-associated long non-coding RNAs (lncRNAs) in AOSD and to evaluate its utility for disease diagnosis and prognostication. METHODS: Expression levels of lncRNAs MIAT, THRIL, NTT, RMRP, PACERR and NEAT1 in peripheral blood mononuclear cells (PBMCs) from treatment-naïve AOSD patients and healthy donors were assessed by quantitative real-time PCR and logistic regression analysis. RESULTS: A diagnostic scoring algorithm was built based on the expression pattern of MIAT, THRIL and RMRP, which could differentiate AOSD from patients with rheumatoid arthritis, systemic lupus erythematosus, or sepsis. Our score could also predict the need of biologics in AOSD treatment. We further followed up ten AOSD patients and found that the expression of NEAT1 was positively correlated with the expression levels of MIAT, THRIL and RMRP after treatment. In poly(I:C)-stimulated THP-1 cell and primary monocytes, MIAT upregulation coupled with THRIL downregulation was similar to the expression pattern observed in AOSD. CONCLUSIONS: Our study provides an AOSD diagnostic scoring system based on the expression signature of MIAT, THRIL and RMRP. Further investigations are needed to uncover the mechanisms of lncRNA dysregulation in AOSD.

Technical Note: Optimization of quantitative susceptibility mapping by streaking artifact detection.

PURPOSE: In quantitative susceptibility mapping (QSM) using magnetic resonance imaging, image reconstruction methods usually aim at suppressing streaking artifacts. In this study, a streaking detection method is proposed for evaluating and optimizing quantitative susceptibility maps. METHODS: Nine healthy subjects participated in this study and underwent three-dimensional multi-echo gradient echo scans. Regularized iterative algorithm was used for reconstruction of tissue susceptibility maps in all subjects. Streaking detection was applied to evaluate streaking artifact in tissue susceptibility maps. In addition, an optimization process for QSM reconstruction by streaking detection was applied and was compared with matching noise level method. RESULTS: It is shown that the proposed streaking detection technique effectively delineates streaking artifact in tissue susceptibility maps. In QSM reconstruction, optimization by streaking detection successfully determines the regularization factor that balances between streaking artifact suppression and tissue texture preservation. ROI analyses of brain tissue susceptibility show that optimization by streaking detection achieves results in good agreement with that from matching noise level method. CONCLUSIONS: Streaking detection enables direct visualization of streaking patterns in tissue susceptibility maps. It can be applied both for evaluating QSM reconstruction quality and for comparing different reconstruction algorithms. Furthermore, streaking detection can be incorporated into an optimization process of QSM reconstruction. Therefore, we conclude that the proposed method will add value to reconstruction of QSM.

Inside-Out Approach of Lumbar Endoscopic Unilateral Laminotomy for Bilateral Decompression: A Detailed Technical Description, Rationale and Outcomes.

Although lumbar stenosis was recognized as a contraindication for endoscopic spine surgery in the past, the advancement in endoscopic system design and development of approach techniques and strategies now enabled the endoscopic spine surgeons to manage all types of lumbar stenosis safely and more effectively. A full-endoscopic lumbar technique for surgical management of spinal canal stenosis is now used today in many advanced spine centers around the world as one of their standard procedures which can be done under general, regional, local anesthesia with sedation. In this technical report, we described in detail the inside-out approach of performing lumbar endoscopic unilateral laminotomy with bilateral decompression (LE-ULBD) and retrospectively reviewed hospital records of 127 patients who underwent the approach from December 2018 to March 2019 to address 1 level lumbar spinal stenosis and determined its outcome after 12-month follow-up period. Perioperative outcomes, operation time, length of hospital stay, and surgical complications were recorded and analyzed. The cross-sectional area of the thecal sac at the operated level was measured. The visual analogue scale (VAS) was assessed preoperatively, 1 month, and 12 months as well as the Oswestry Disability Index (ODI). The data were statistically analyzed (using SPSS ver. 17.0). The inside-out approach LE-ULBD was shown to effect statistically significant improvement in the VAS of leg and back pain as well as the ODI. It is a familiar, safe, and effective way of performing spinal stenosis decompression with good reproducible outcomes.

The Turkey Digit: A New Training Model for Digit Replantation.

PURPOSE: Replant survival rates have reportedly declined over the past decade. Although this problem is multifactorial, 1 potential solution may include the development of a relevant teaching model. The development of an in vivo animal model that can be used for surgical training could enhance surgeon and resident experience and potentially improve outcomes. Here, we present a novel training model for digit replantation using turkey digits. METHODS: Six mature male Bourbon Red turkeys were included in this study. With the animal under general anesthesia, the third digit on either the left or the right foot was randomly selected and amputated. The medial and lateral digital neurovascular bundles were dissected on both sides and the digit was replanted. Perfusion was confirmed prior to skin closure. The foot was casted prior to extubating the turkeys. Turkeys were then placed in a non-weight-bearing sling. Digit status was evaluated twice daily. RESULTS: All 6 replanted digits were viable immediately after surgery and for at least 24 hours after surgery. The average digit survival was 6 days with a maximum survival of 15 days. All digits were eventually lost owing to a variety of reasons including infection and arterial thrombosis. CONCLUSIONS: The turkey digit proved to be a successful short-term animal training model for digit replantation. Future studies are needed to determine optimum standard surgical procedure and postoperative care to maximize the educational benefits of this training model. CLINICAL RELEVANCE: To establish an animal model that can simulate digital replantation.

Time Course Observation of Outcomes between Minimally Invasive Transforaminal Lumbar Interbody Fusion and Posterior Lumbar Interbody Fusion.

The purpose of this study is to compare the long-term patient-outcomes, spinal fusion, and incidence of adjacent segment degeneration (ASD) between minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and open posterior lumbar interbody fusion (O-PLIF). We retrospectively reviewed 70 consecutive cases who underwent single-level MIS-TLIF or O-PLIF from March 2010 to July 2013. All the patients achieved a minimum of 5-year follow-up. Data collected for each patient included demographic data, perioperative data, and complications. Clinical outcomes were evaluated with Oswestry disability index and visual analogue scale (VAS). Radiological outcomes included fusion rate and ASD. About 34 patients of MIS-TLIF and 36 patients of O-PLIF were enrolled. Higher Charlson comorbidity index scores were noted in MIS-TLIF than in O-PLIF. Blood loss was significantly lower in MIS-TLIF than O-PLIF. There were significant improvements in clinical and radiological outcomes in both groups. At 6 months, in MIS-TLIF group had significantly lower VAS for back pain and disc height compared with in O-PLIF group. The fusion rate was similar between the two groups at 5-year follow-up. Although the total complication rates were similar between the two groups, both the incidence of ASD was significantly higher in O-PLIF group than MIS-TLIF group (P = 0.032). In conclusion, this study indicates that MIS-TLIF is comparable to O-PLIF in terms of fusion rates and clinical outcomes in single-segment degenerative lumbar diseases. In addition, compared with O-PLIF, MIS-TLIF has the advantages of lesser blood loss, faster recovery, and lower incidence of ASD.

Percutaneous Stenoscopic Lumbar Decompression with Paramedian Approach for Foraminal/Extraforaminal Lesions.

The lumbar foramen is affected by different degenerative diseases, including extraforaminal disc herniation, foraminal stenosis (FS), and degenerative or spondylolytic spondylolisthesis. The purpose of this study was to describe percutaneous stenoscopic lumbar decompression with a paramedian approach (para-PSLD) for foraminal/extraforaminal lesions. All operative procedures were performed using a complete uniportal endoscopic instrument system. The para-PSLD can be easily applied to patients with FS and narrow disc space or facet joint hypertrophy. The anatomical view of a para-PSLD is similar to that of a conventional open surgery and allows for good visualization of the foraminal/extraforaminal areas. We suggest that para-PSLD is an alternative and minimally invasive procedure to treat degenerative lumbar foraminal/extraforaminal stenoses.

Endoscopic Rescue Technique for Iatrogenic Sacroiliac Joint Syndrome Caused by Sextant Percutaneous Pedicle Screw Fixation System.

BACKGROUND: The Sextant percutaneous pedicle screw fixation system is a commonly used technique. In this system, the pedicle screw and the sharp rod are placed through stab incisions. The unique mechanism of action of this system may cause unprecedented adverse effects, such as iatrogenic sacroiliac (SI) joint syndrome. CASE DESCRIPTION: A patient presented with iatrogenic SI joint syndrome caused by the rod of the Sextant system at the L4-L6 level causing ilium irritation and dynamic SI joint instability. The patient was treated with an endoscopy-based technique. This is the first report of endoscopic treatment for iatrogenic SI joint syndrome as an adverse effect resulting from use of the Sextant system. CONCLUSIONS: Surgeons need to be aware of iatrogenic SI joint syndrome using the Sextant system when performing percutaneous pedicle screw fixation. An endoscopy-based technique may be an effective alternative to conventional corrective surgery when treating iatrogenic SI joint syndrome using the Sextant system.

Therapeutic Feasibility of Full Endoscopic Decompression in One- to Three-Level Lumbar Canal Stenosis via a Single Skin Port Using a New Endoscopic System, Percutaneous Stenoscopic Lumbar Decompression.

STUDY DESIGN: This retrospective study involved 450 consecutive cases of degenerative lumbar stenosis treated with percutaneous stenoscopic lumbar decompression (PSLD). PURPOSE: We determined the feasibility of PSLD for lumbar stenosis at single and multiple levels (minimum 1-year follow-up) by image analysis to observe postoperative widening of the vertebral canal in the area. OVERVIEW OF LITERATURE: The decision not to perform an endoscopic decompression might be due to the surgeon being uncomfortable with conventional microscopic decompression or unfamiliar with endoscopic techniques or the unavailability of relevant surgical tools to completely decompress the spinal stenosis. METHODS: The decompressed canal was compared between preoperative controls and postoperative treated cases. Data on operative results, including length of stay, operative time, and surgical complications, were analyzed. Patients were assessed clinically on the basis of the Visual Analog Scale (VAS) score for the back and legs and using the Oswestry Disability Index (ODI). RESULTS: Postoperative magnetic resonance imaging revealed that PSLD increased the canal cross-sectional area by 52.0% compared with the preoperative area at the index segment (p<0.001) and demonstrated minimal damage to the normal soft tissues including muscles and the extent of removed normal bony tissues. Mean improvements in VAS score and ODI were 4.0 (p<0.001) and 40% (p<0.001), respectively. CONCLUSIONS: PSLD could be an alternative to microscopic or microendoscopic decompression with various advantages in the surgical management of lumbar stenosis.

Percutaneous Stenoscopic Lumbar Decompression with Paramedian Approach for Foraminal/Extraforaminal Lesions

The lumbar foramen is affected by different degenerative diseases, including extraforaminal disc herniation, foraminal stenosis (FS), and degenerative or spondylolytic spondylolisthesis. The purpose of this study was to describe percutaneous stenoscopic lumbar decompression with a paramedian approach (para-PSLD) for foraminal/extraforaminal lesions. All operative procedures were performed using a complete uniportal endoscopic instrument system. The para-PSLD can be easily applied to patients with FS and narrow disc space or facet joint hypertrophy. The anatomical view of a para-PSLD is similar to that of a conventional open surgery and allows for good visualization of the foraminal/extraforaminal areas. We suggest that para-PSLD is an alternative and minimally invasive procedure to treat degenerative lumbar foraminal/extraforaminal stenoses.

Therapeutic Feasibility of Full Endoscopic Decompression in One- to Three-Level Lumbar Canal Stenosis via a Single Skin Port Using a New Endoscopic System, Percutaneous Stenoscopic Lumbar Decompression

STUDY DESIGN: This retrospective study involved 450 consecutive cases of degenerative lumbar stenosis treated with percutaneous stenoscopic lumbar decompression (PSLD). PURPOSE: We determined the feasibility of PSLD for lumbar stenosis at single and multiple levels (minimum 1-year follow-up) by image analysis to observe postoperative widening of the vertebral canal in the area. OVERVIEW OF LITERATURE: The decision not to perform an endoscopic decompression might be due to the surgeon being uncomfortable with conventional microscopic decompression or unfamiliar with endoscopic techniques or the unavailability of relevant surgical tools to completely decompress the spinal stenosis. METHODS: The decompressed canal was compared between preoperative controls and postoperative treated cases. Data on operative results, including length of stay, operative time, and surgical complications, were analyzed. Patients were assessed clinically on the basis of the Visual Analog Scale (VAS) score for the back and legs and using the Oswestry Disability Index (ODI). RESULTS: Postoperative magnetic resonance imaging revealed that PSLD increased the canal cross-sectional area by 52.0% compared with the preoperative area at the index segment (p<0.001) and demonstrated minimal damage to the normal soft tissues including muscles and the extent of removed normal bony tissues. Mean improvements in VAS score and ODI were 4.0 (p<0.001) and 40% (p<0.001), respectively. CONCLUSIONS: PSLD could be an alternative to microscopic or microendoscopic decompression with various advantages in the surgical management of lumbar stenosis.

Double-Layer TachoSil Packing for Management of Incidental Durotomy During Percutaneous Stenoscopic Lumbar Decompression.

BACKGROUND: Incidental durotomy (ID) during surgery for lumbar herniated disks or lumbar spinal stenosis is a serious complication that requires immediate recognition and repair. The incidence of ID during percutaneous endoscopic lumbar decompression has increased along with the demand for endoscopic spinal surgery. The management of ID during endoscopic surgery is more complicated and difficult than management during open surgery. A hemostatic agent, TachoSil (Nycomed, Linz, Austria), is used for control of local bleeding in several types of surgery, but its use in dural repair in endoscopic spinal surgery has not been described. CASE DESCRIPTION: We present 3 cases in which the double-layer TachoSil packing technique was used in the management of ID during percutaneous stenoscopic lumbar decompression. CONCLUSIONS: This case report reconfirms the efficacy and utility of TachoSil for IDs that occur during endoscopic spinal surgery and minimally invasive surgery. To our knowledge, this is the first report on the use and effectiveness of TachoSil for managing IDs during endoscopic spinal surgery. We hope that other surgeons will find this technique helpful in managing IDs.

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.

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.