Unilateral Biplanar Screw-Rod Fixation Technique for the Treatment of Odontoid Fractures in Patients with Atlantoaxial Bone or Vascular Abnormalities.

OBJETIVE: This study aims to introduce the unilateral biplanar screw-rod fixation (UBSF) technique (a hybrid fixation technique: 2 sets of atlantoaxial screws were placed on the same side), which serves as a salvage method for traditional posterior atlantoaxial fixation. To summarize the indications of this technique and to assess its safety, feasibility, and clinical effectiveness in the treatment of odontoid fractures. METHODS: Patients with odontoid fractures were enrolled according to special criteria. Surgical duration and intraoperative blood loss were documented. Patients were followed up for a minimum of 12 months. X-ray and computerized tomography scans were conducted and reviewed at 1 day, and patients were asked to return for computerized tomography reviews at 3, 6, 9, and 12 months after surgery until fracture union. Recorded and compared the Neck Visual Analog Scale and Neck Disability Index presurgery and at 1 week and 12 months postsurgery. RESULTS: Between January 2016 and December 2022, our study enrolled 7 patients who were diagnosed with odontoid fractures accompanied by atlantoaxial bone or vascular abnormalities. All 7 patients underwent successful UBSF surgery, and no neurovascular injuries were recorded during surgery. Fracture union was observed in all patients, and the Neck Visual Analog Scale and Neck Disability Index scores improved significantly at 1 week and 12 months postoperative (P < 0.01). CONCLUSIONS: The UBSF technique has been demonstrated to be safe, feasible, and effective in treating odontoid fractures. In cases where the atlantoaxial bone or vascular structure exhibits abnormalities, it can function as a supplementary or alternative approach to the conventional posterior C1-2 fixation.

The SIRT1 activator SRT2104 promotes BMP9-induced osteogenic and angiogenic differentiation in mesenchymal stem cells.

Bone defects resulting from trauma, bone tumors, infections and skeletal abnormalities are a common osteoporotic condition with respect to clinical treatment. Of the known bone morphogenetic proteins (BMPs), BMP9 has the strongest osteogenic differentiation potential, which could be beneficial in the construction of tissue-engineered bone. Silent mating type information regulator 2 homolog-1 (SIRT1) is a highly conserved nicotinamide adenine dinucleotide-dependent deacetylase that deacetylates and modulates histone or non-histone substrates. However, the role of SIRT1 in BMP9-induced osteogenic differentiation of stem cells has not been studied. Furthermore, it is unclear whether SIRT1 interacts with the BMP/Smad and BMP/MAPK pathways in stem cells. We found that SIRT1 expression decreased gradually in a time-dependent manner during BMP9-induced osteogenic differentiation of MSCs. Interactions between SIRT1 and Smad7 promoted degradation of Smad7 and increased Smad1/5/8 phosphorylation. SRT2104, an activator of SIRT, enhanced the expression of osteogenic- and angiogenic-related proteins in BMP9-induced MSCs. In addition, we found that activation of the BMP/MAPK pathway led to osteogenic and angiogenic differentiation of MSCs. Our study demonstrated that SIRT1 expression decreased during BMP9-induced differentiation. The SIRT1 activator SRT2104 promoted BMP9-induced osteogenic and angiogenic differentiation of MSCs through the BMP/Smad and BMP/MAPK signaling pathways.

Intra-articular Injection of Kartogenin-Enhanced Bone Marrow-Derived Mesenchymal Stem Cells in the Treatment of Knee Osteoarthritis in a Rat Model.

BACKGROUND: In this study, we investigated the in vitro and in vivo chondrogenic capacity of kartogenin (KGN)-enhanced bone marrow-derived mesenchymal stem cells (BMSCs) for cartilage regeneration. PURPOSE: To determine (1) whether functionalized nanographene oxide (NGO) can effectively deliver KGN into BMSCs and (2) whether KGN would enhance BMSCs during chondrogenesis in vitro and in vivo in an animal model. STUDY DESIGN: Controlled laboratory study. METHODS: Functionalized NGO with line chain amine-terminated polyethylene glycol (PEG) and branched polyethylenimine (BPEI) were used to synthesize biocompatible NGO-PEG-BPEI (PPG) and for loading hydrophobic KGN molecules noncovalently via π-π stacking and hydrophobic interactions (PPG-KGN). Then, PPG-KGN was used for the intracellular delivery of hydrophobic KGN by simple mixing and co-incubation with BMSCs to acquire KGN-enhanced BMSCs. The chondrogenic efficacy of KGN-enhanced BMSCs was evaluated in vitro. In vivo, osteoarthritis (OA) was induced by anterior cruciate ligament transection in rats. A total of 5 groups were established: normal (OA treated with nothing), phosphate-buffered saline (PBS; intra-articular injection of PBS), PPG-KGN (intra-articular injection of PPG-KGN), BMSCs (intra-articular injection of BMSCs), and BMSCs + PPG-KGN (intra-articular injection of PPG-KGN-preconditioned BMSCs). At 6 and 9 weeks after the surgical induction of OA, the rats received intra-articular injections of PPG-KGN, BMSCs, or KGN-enhanced BMSCs. At 14 weeks after the surgical induction of OA, radiographic and behavioral evaluations as well as histological analysis of the knee joints were performed. RESULTS: The in vitro study showed that PPG could be rapidly uptaken in the first 4 hours after incubation, reaching saturation at 12 hours and accumulating in the lysosome and cytoplasm of BMSCs. Thus, PPG-KGN could enhance the efficiency of the intracellular delivery of KGN, which showed a remarkably high chondrogenic differentiation capacity of BMSCs. When applied to an OA model of cartilage injuries in rats, PPG-KGN-preconditioned BMSCs contributed to protection from joint space narrowing, pathological mineralization, OA development, and OA-induced pain, as well as improved tissue regeneration, as evidenced by radiographic, weightbearing, and histological findings. CONCLUSION: Our results demonstrate that KGN-enhanced BMSCs showed markedly improved capacities for chondrogenesis and articular cartilage repair. We believe that this work demonstrates that a multifunctional nanoparticle-based drug delivery system could be beneficial for stem cell therapy. Our results present an opportunity to reverse the symptoms and pathophysiology of OA. CLINICAL RELEVANCE: The intracellular delivery of KGN to produce BMSCs with enhanced chondrogenic potential may offer a new approach for the treatment of OA.

The role of Serpina3n in the reversal effect of ATRA on dexamethasone-inhibited osteogenic differentiation in mesenchymal stem cells.

BACKGROUND: Glucocorticoid-induced osteoporosis (GIOP) is the most common secondary osteoporosis. Patients with GIOP are susceptible to fractures and the subsequent delayed bone union or nonunion. Thus, effective drugs and targets need to be explored. In this regard, the present study aims to reveal the possible mechanism of the anti-GIOP effect of all-trans retinoic acid (ATRA). METHODS: Bone morphogenetic protein 9 (BMP9)-transfected mesenchymal stem cells (MSCs) were used as an in vitro osteogenic model to deduce the relationship between ATRA and dexamethasone (DEX). The osteogenic markers runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), and osteopontin were detected using real-time quantitative polymerase chain reaction, Western blot, and immunofluorescent staining assay. ALP activities and matrix mineralization were evaluated using ALP staining and Alizarin Red S staining assay, respectively. The novel genes associated with ATRA and DEX were detected using RNA sequencing (RNA-seq). The binding of the protein-DNA complex was validated using chromatin immunoprecipitation (ChIP) assay. Rat GIOP models were constructed using intraperitoneal injection of dexamethasone at a dose of 1 mg/kg, while ATRA intragastric administration was applied to prevent and treat GIOP. These effects were evaluated based on the serum detection of the osteogenic markers osteocalcin and tartrate-resistant acid phosphatase 5b, histological staining, and micro-computed tomography analysis. RESULTS: ATRA enhanced BMP9-induced ALP, RUNX2 expressions, ALP activities, and matrix mineralization in mouse embryonic fibroblasts as well as C3H10T1/2 and C2C12 cells, while a high concentration of DEX attenuated these markers. When DEX was combined with ATRA, the latter reversed DEX-inhibited ALP activities and osteogenic markers. In vivo analysis showed that ATRA reversed DEX-inhibited bone volume, bone trabecular number, and thickness. During the reversal process of ATRA, the expression of retinoic acid receptor beta (RARß) was elevated. RARß inhibitor Le135 partly blocked the reversal effect of ATRA. Meanwhile, RNA-seq demonstrated that serine protease inhibitor, clade A, member 3N (Serpina3n) was remarkably upregulated by DEX but downregulated when combined with ATRA. Overexpression of Serpina3n attenuated ATRA-promoted osteogenic differentiation, whereas knockdown of Serpina3n blocked DEX-inhibited osteogenic differentiation. Furthermore, ChIP assay revealed that RARß can regulate the expression of Serpina3n. CONCLUSION: ATRA can reverse DEX-inhibited osteogenic differentiation both in vitro and in vivo, which may be closely related to the downregulation of DEX-promoted Serpina3n. Hence, ATRA may be viewed as a novel therapeutic agent, and Serpina3n may act as a new target for GIOP.

Long non-coding RNA (LncRNA) HOTAIR regulates BMP9-induced osteogenic differentiation by targeting the proliferation of mesenchymal stem cells (MSCs).

Long non-coding RNAs are important regulators of biological processes, but their roles in the osteogenic differentiation of mesenchymal stem cells (MSCs) remain unclear. Here we investigated the role of murine HOX transcript antisense RNA (mHotair) in BMP9-induced osteogenic differentiation of MSCs using immortalized mouse adipose-derived cells (iMADs). Touchdown quantitative polymerase chain reaction analysis found increased mHotair expression in bones in comparison with most other tissues. Moreover, the level of mHotair in femurs peaked at the age of week-4, a period of fast skeleton development. BMP9 could induce earlier peak expression of mHotair during in vitro iMAD osteogenesis. Silencing mHotair diminished BMP9-induced ALP activity, matrix mineralization, and expression of osteogenic, chondrogenic and adipogenic markers. Cell implantation experiments further confirmed that knockdown of mHotair attenuated BMP9-induced ectopic bone formation and mineralization of iMADs, leading to more undifferentiated cells. Crystal violet staining and cell cycle analysis revealed that silencing of mHotair promoted the proliferation of iMAD cells regardless of BMP9 induction. Moreover, ectopic bone masses developed from mHotair-knockdown iMAD cells exhibited higher expression of PCNA than the control group. Taken together, our results demonstrated that murine mHotair is an important regulator of BMP9-induced MSC osteogenesis by targeting cell cycle and proliferation.

Posterior Percutaneous Transpedicular Endoscopic Approach for Treating Single-Segment Cervical Myelopathy.

BACKGROUND: Standard posterior percutaneous endoscopic cervical discectomy (PECD) is considered an effective minimally invasive surgery. Although standard PECD can be used to treat radiculopathy with relatively minimal trauma, it is still a challenge to use this approach for treating myelopathy. OBJECTIVE: This report is aimed at first describing a posterior transpedicular approach under endoscopy for myelopathy and evaluating the feasibility and short-term clinical effects of this approach. METHODS: In our retrospective analysis between Feb. 2016 to Mar. 2017, 16 patients managed with PECD using the posterior transpedicular approach for symptomatic single-segment myelopathy. Surgery involved drilling 1/2 to 2/3 of the medial portion of the pedicle under endoscopy to provide sufficient space and an appropriate angle for inserting the endoscope into the spinal canal, followed by ventral decompression of the spinal cord. Computed tomography and magnetic resonance imaging were used to evaluate pedicle healing and spinal cord decompression. The primary outcomes included a visual analog scale (VAS) scores of axial neck pain and Japanese Orthopaedic Association (JOA) scores of neurological conditions. RESULTS: All patients completed a 1-year follow-up examination. The mean duration of surgery was 95.44 ± 19.44 min (52-130 min). The fluoroscopy duration was 5.88 ± 1.05 (4-7). The VAS scores of axial pain significantly improved from 6.94 ± 0.75 preoperatively to 2.88 ± 1.22 postoperatively (P < 0.05). The mean JOA scores improved from 8.50 ± 1.12 preoperatively to 14.50 ± 1.46 at the final follow-up (P < 0.05). The effects were excellent in 8 cases, good in 6 cases, and fair in 2 cases. After partial pedicle excision, the width of the remaining pedicle was 1.70 ± 0.22 mm postoperatively and significantly recovered to 3.38 ± 0.49 mm at the 1-year follow-up. There were no surgery-related complications, such as dural tearing, spinal cord injury, nerve root injury, pedicle fracture, and cervical hematocele or infection. CONCLUSIONS: The posterior transpedicular approach is an effective method for the treatment of myelopathy in select patients and is a supplement to the described surgical approach for PECD.

Niclosamide: drug repurposing for human chondrosarcoma treatment via the caspase-dependent mitochondrial apoptotic pathway.

Poor sensitivity to chemotherapy drugs and high recurrence rates are the bottlenecks to successful chondrosarcoma treatment. Notably, niclosamide has been identified as a potential anti-cancer agent. To investigate the effects and mechanisms of niclosamide in the context of human chondrosarcoma treatment, SW1353 and CAL78 human chondrosarcoma cells were treated with various concentrations of niclosamide. The CKK-8 assay was performed to quantify cell viability. Cell proliferation was determined with crystal violet staining and colony forming assays. TUNEL and annexin V-FITC flow cytometry assays were performed to detect cell apoptosis. Wound healing and Transwell assays were conducted to evaluate migratory and invasive cell behaviors. The effect of niclosamide on the mitochondria was evaluated with the JC-1 and Seahorse Cell Mito Stress Assays. The expression of caspase-3, cleaved caspase-3, caspase-9, cleaved caspase-9, and ß-tubulin levels were investigated by western blotting. Collectively, the data demonstrated that niclosamide inhibited cell growth and proliferation, attenuated migratory and invasive cell behaviors, and promoted apoptosis. Niclosamide is as a potent chondrosarcoma tumor inhibitor that activates the caspase-dependent mitochondrial apoptotic pathway and could be a novel therapeutic approach to treat chondrosarcoma.

The combinations of multiple factors to improve the diagnostic sensitivity and specificity after artificial joint infection.

OBJECTIVE: To discuss the sensitivity and specificity of the combinations of multiple factors that work on bone infection after artificial joint, and provide evidence-based medical basis for the early diagnosis of infection after artificial joint. METHODS: A retrospective review was conducted on 35 patients diagnosed with periprosthetic joint infections (PJI) or aseptic loosening (AL) who both received revision operation from January 2011 to January 2015. Analyzing and comparing their epidemiology indexes and expounded a series of auxiliary examinations corresponding positive diagnosis ratio. RESULTS: Thirty-five patients were divided into two groups. One is called group PJI which includes 16 patients, and the other is called group AL which contains 19 patients. There was no statistical difference between in age (p = 0.536), gender ratio (p = 0.094), and the time of catching infection or getting loose (p = 0.055). Swelling was statistical significant (p = 0.0435 < 0.05). AUC of CRP = 0.947, ESR = 0.893, IL-6 = 0.893, PCT = 0.781, WBC = 0.839, and PMN = 0.755, respectively, CRP has a high diagnostic value to PJI, ESR, IL-6, PCT, WBC, and PMN% possess a moderate diagnostic value. There were 3 cases of PJI whose pathological paraffin section showed infectious inflammatory cells (100%). three PJI patients and one AL patient whose 99mTc-MDP examination presented 100% infection or looseness rate. CONCLUSION: CRP has a high diagnostic value to PJI. Histopathology HE staining, Gram staining, and 99mTc-MDP provide a highly accurate diagnosis for PJI. Therefore, the results suggest combining the unique clinical symptoms of PJI patients with relevant laboratory indexes, histopathologic characteristics, and imageological examinations that can improve diagnostic sensitivity and specificity of PJI in its early stage.

Endoscopically-Assisted Percutaneous Unilateral Atlantoaxial Screw-Rod Nonfusion Fixation Treatment for Type II Odontoid Fractures in Geriatric Patients: Case Series and Technical Note.

BACKGROUND: Considerable controversy exists regarding the optimal treatment for type II odontoid fractures in geriatric patients. Surgical intervention can help patients return to their prior level of function as rapidly as possible while avoiding the morbidity and mortality associated with prolonged and bedbound hospitalization. However, the optimal treatment is still a difficult choice for patients with increased risk from anesthesia. OBJECTIVES: The objective of our study was to describe an innovative method of endoscopically-assisted percutaneous unilateral C1 lateral mass screw and C2 pedicle screw-rod nonfusion fixation for type II odontoid fractures in geriatric patients. STUDY DESIGN: A case series design and technical notes. SETTING: This study took place at Second Affiliated Hospital of Chongqing Medical University. METHODS: Seven geriatric patients (> 65 years) with type II odontoid fractures and an American Society of Anesthesiologists (ASA) score of 2 or higher received endoscopically-assisted percutaneous unilateral atlantoaxial screw-rod nonfusion fixation. After surgery, all patients were required to wear a rigid collar full-time for 12 weeks. Intraoperative data, the bone union time, American Spinal Injury Association (ASIA) scale scores, Neck Disability Index (NDI) scores, and postoperative complications were collected for assessment.RESULTS The surgical goal was successfully achieved in all patients, 3 of whom had high ASA scores (>= 3) and underwent surgery under local anesthesia. The operative time ranged from 112 to 169 minutes (mean, 131.1 minutes). No neurovascular complications were observed intraoperatively or postoperatively. All patients rapidly returned to their prior level of function and were followed up for 12 to 24 months (average: 16.9 months). Bone union was achieved in all patients. LIMITATIONS: This study is limited by being a retrospective study. CONCLUSIONS: Endoscopically-assisted percutaneous unilateral atlantoaxial screw-rod nonfusion fixation is a feasible technique for type II odontoid fractures in geriatric patients. This method offers a compromise between non-operative and operative treatment and allows geriatric patients to rapidly return to their prior level of function. KEY WORDS: Endoscopically-assisted surgery; geriatric patient; percutaneous atlantoaxial fixation; type II odontoid fracture; unilateral nonfusion fixation.

LSD1 negatively regulates autophagy in myoblast cells by driving PTEN degradation.

Lysine-specific demethylase 1 (LSD1) is a well characterized transcriptional regulator functioning on the chromatin to remove mono- and di-methyl groups from lysine 4 or lysine 9 of histone 3 (H3K4 or H3K9). LSD1 also has non-transcriptional activities via targeting non-histone substrates that participate in diverse biological processes. In this report, we determined that LSD1 negatively regulates autophagy in skeletal muscle cells by promoting PTEN degradation in a transcription-independent mechanism. In C2C12 cells, LSD1 inhibition or depletion significantly induced the initiation of autophagy; and autophagy resulted from LSD1 inhibition is associated with AKT/mTORC1 inactivation. Notably, the proteins of PTEN, a prominent repressive AKT modulator, are stabilized by LSD1 inhibition despite a decrease of its mRNA levels. Further data demonstrated that LSD1 interacts with PTEN protein and enhances its ubiquitination and degradation. Together, our findings identify a novel biological function of LSD1 in autophagy, mediated by regulating the stability of PTEN and the activity of AKT/mTORC1.

Modified K-Hole Percutaneous Endoscopic Surgery for Cervical Foraminal Stenosis: Partial Pediculectomy Approach.

BACKGROUND: Percutaneous endoscopic cervical discectomy has evolved as an efficient, minimally invasive spine surgery for radiculopathy caused by soft and/or osseous foraminal stenosis. Although interlaminar access can be used to resect lateral herniated lesions or osteophytes located in the foramina, with limited operative space, nerve retraction may be unavoidable. This procedure may injure the nerve root and cause postoperative arm pain, numbness, and muscle weakness, especially when the herniation is located in the ventral nerve root or when there is a massive osteophyte in the foramina. However, posterior partial cervical pediculectomy under endoscopy provides a new approach to effectively reduce or even avoid nerve retraction and reduce the potential risk of nerve injury. OBJECTIVES: This report presents a partial pediculectomy approach and compares the clinical outcomes of different surgical methods, including posterior percutaneous endoscopic cervical discectomy (P-PECD) and P-PECD combined with partial pediculectomySTUDY DESIGN: This study used a retrospective comparative study design. SETTING: This study took place at the Second Affiliated Hospital of Chongqing Medical University. METHODS: From February 2015 to March 2017, 84 patients with single-level and unilateral soft and/or osseous cervical foraminal stenosis were recruited. Patients were treated with P-PECD (40 patients) and P-PECD combined with partial pediculectomy (44 patients). Postoperative clinical outcomes were assessed using the modified MacNab grading criteria and the Visual Analog Scale (VAS) at different times after surgery. The surgery duration, dosage of postoperative analgesic medication, duration of hospital stay, and postoperative complications were recorded. RESULTS: The mean duration of the conventional P-PECD surgery was 74.48 ± 7.08 minutes, which was significantly longer (P = 0.002) than that observed for the P-PECD with partial pediculectomy (66.00 ± 9.62 minutes). The analgesic dosage in the conventional P-PECD group was significantly higher than that in the partial pediculectomy group (9.14 ± 3.07 units vs. 5.71 ± 3.41 units; P = 0.001). The hospital stay in the conventional P-PECD group was significantly longer than that in the partial pediculectomy group (3.86 ± 0.85 days vs. 3.24 ± 0.83 days; P = 0.022). The VAS scores at 1 day, 3 days, and 7 days after surgery in the conventional P-PECD group were significantly higher than those in the partial pediculectomy group (all P < 0.001). The modified MacNab grading criteria showed no significant difference at each follow-up (P = 1). The incidence of complications in the P-PECD with partial pediculectomy group (2/44, 4.55%) was significantly lower than that in the conventional P-PECD group (4/40, 10.0%), including complications of increased pain, increased numbness, and worsening of muscle weakness. LIMITATIONS: This study is limited by being a retrospective study, and by having a small sample size and a short follow-up period. CONCLUSIONS: As an alternative to the P-PECD surgical technique, P-PECD with partial pediculectomy effectively reduced the postoperative complications and may be preferable when considering the surgery duration, postoperative hospital stay, analgesic dosage, and postoperative VAS score. KEY WORDS: Cervical disc herniation, foraminal stenosis, percutaneous endoscopic cervical discectomy, PECD, P-PECD, partial pediculectomy.

IGF-1 reverses the osteogenic inhibitory effect of dexamethasone on BMP9-induced osteogenic differentiation in mouse embryonic fibroblasts via PI3K/AKT/COX-2 pathway.

Glucocorticoid-Induced Osteoporosis (GIOP) is a prevalent clinical complication caused by large dose administration of glucocorticoids, such as Dexamethasone (Dex) and Prednisone. GIOP may lead to fractures and even Osteonecrosis of the Femoral Head (ONFH). It has been reported that glucocorticoids inhibit osteogenesis via the suppression of osteogenic differentiation in Mesenchymal Stem Cells (MSCs), but the precise mechanism underlying this suppression awaits further investigation. Meanwhile, novel and efficacious therapies are recommended to cope with GIOP. In this study, we demonstrated that Dex had the inhibitory effect on Bone Morphogenetic Protein 9 (BMP9)-induced ALP activities and matrix mineralization in Mouse Embryonic Fibroblasts (MEFs). In addition, the study confirmed that Dex decreased the expression of osteogenic markers such as Runx2 and OPN. However, the inhibitory effect of Dex on these osteogenic markers can be reversed when combined with insulin-like growth factor 1 (IGF-1). Regarding the inhibitory mechanism, we found that the level of AKT and p-AKT can be decreased by Dex and that Ly294002, the PI3K inhibitor, can block the reversal effect of IGF-1. Moreover, the knockdown or inhibition of COX-2 produced similar results to those of Ly294002. Our findings indicated that IGF-1 may reverse the osteogenic inhibitory effect of Dex via PI3K/AKT pathway, which may be associated with the up-regulation of COX-2. This study may provide new clinical management strategy for GIOP cases.

A Novel Posterior Trench Approach Involving Percutaneous Endoscopic Cervical Discectomy for Central Cervical Intervertebral Disc Herniation.

OBJECTIVE: This report describes a novel posterior trench approach involving percutaneous endoscopic cervical discectomy (PECD) for central cervical intervertebral disc herniation (CIVDH) and an evaluation of the feasibility, safety, and short-term clinical effect of this approach. BACKGROUND CONTEXT: Central CIVDH is considered the contraindication for posterior PECD. MATERIALS AND METHODS: A single-center retrospective observational study was performed with 30 patients managed with posterior PECD using the trench approach for symptomatic single-level central CIVDH. Primary outcomes included the measures of bodily pain and physical function based on the SF-36 and modified MacNab criteria. Radiographical follow-up included the static and dynamic cervical plain radiographs, computed tomographic scans, and magnetic resonance images. RESULTS: A positive clinical response for symptom relief was achieved in all patients. The postoperative MRI showed total removal of the herniated disc. CONCLUSIONS: As a supplement to the described surgical techniques of PECD, this trench approach provides novel access for the treatment of CIVDH, especially for the central type. The advantages of this technique include the provision of access to decompress the ventral region of the thecal sac and the ability to avoid damage to the facet joint. The steep learning curve might be a major disadvantage, and the sample volume is a limitation of the study; the effectiveness and reliability of the trench approach should be further verified in a comparative cohort study with a large volume of patients.

Anterior Transcorporeal Approach to Percutaneous Endoscopic Cervical Diskectomy for Single-Level Cervical Intervertebral Disk Herniation: Case Series with 2-Year Follow-Up.

OBJECTIVE: To examine the effects of anterior transcorporeal percutaneous endoscopic cervical diskectomy (ATPECD) for the treatment of single-level cervical intervertebral disk herniation (CIDH) with a focus on its safety, feasibility, clinical efficacy, and specific possible complications. METHODS: A series of 35 patients with symptomatic single-level CIDH were enrolled to be treated with ATPECD. Neck and arm pain was measured using the visual analog scale. Quality of life was measured using the bodily pain and physical function on the SF-36. The average disk height and vertical vertebral body height were recorded. Bone healing was evaluated on the basis of postoperative computed tomography. RESULTS: Successful removal of the herniated disk was confirmed in all 35 cases. At 2 years, the patients showed a significant treatment effect in the visual analog scale and body pain and physical function portions of the SF-36 (1.14 ± 0.60 vs. 7.62 ± 0.61, 63.92 ± 6.74 vs. 32.55 ± 6.80, and 82.14 ± 6.22 vs. 34.43 ± 4.50, respectively, P < 0.01). Mean preoperative disk height was 6.79 ± 0.37 mm, which decreased to 6.34 ± 0.46 mm 2 years post operation (6.6% decrease). Preoperative surgical vertebral body height also decreased from preoperation (15.79 ± 0.52 mm) to 2 years post operation (15.12 ± 0.38 mm) (4.2% decrease). Three surgery-related complications were observed (8.6%). CONCLUSIONS: Preliminary clinical experience with ATPECD shows that it is safe, effective, feasible, and minimally invasive. Although it has some disadvantages, such as the need for repeated fluoroscopy, some minor complications, and nonsymptomatic disk height decreases, ATPECD can supplement minimally invasive surgeries in selected cases of CIDH.

Treatment of Single-Level Thoracic Tuberculosis by Percutaneous Endoscopic Débridement and Allograft via the Transforaminal Approach Combined with Percutaneous Pedicle Screw Fixation: A Multicenter Study with a Median Follow-Up of 36 Months.

OBJECTIVE: To examine effects of percutaneous endoscopic débridement and allograft via the transforaminal approach combined with percutaneous pedicle screw fixation as treatment for single-level thoracic tuberculosis. METHODS: This multicenter retrospective analysis included 75 patients with single-level thoracic tuberculosis who underwent percutaneous endoscopic débridement and allograft via the transforaminal approach combined with percutaneous pedicle screw fixation and were followed for >36 months between January 2012 and December 2014. RESULTS: Follow-up was 36-48 months (average 41.1 ± 2.2 months). Intraoperative blood loss was low (average 30.5 ± 7.9 mL), and bed rest time was short (average 1.5 ± 0.3 days). No recurrence was observed in all 75 patients. Except for 3 patients, almost all patients (96%) achieved grade I or II fusion in interbody bone grafting. Segmental Cobb angle was 13.5° ± 4.1° before surgery, 10.5° ± 3.7° immediately after surgery, and 11.7° ± 3.9° at 36 months of follow-up. All patients achieved complete recovery of neurologic function (American Spinal Injury Association grade E), including 15 patients with spinal cord injury (American Spinal Injury Association grade D) before surgery. The visual analog scale and 36-Item Short-Form Health Survey scores significantly improved at 1, 3, 12, and 36 months of follow-up. No complications related to internal fixation occurred within the follow-up period; complication rate was 9.0%. CONCLUSIONS: Median follow-up clinical experience with percutaneous endoscopic débridement and allograft via the transforaminal approach combined with percutaneous pedicle screw fixation indicates that the technique is safe, effective, feasible, and minimally invasive.

Usage of Bone Wax to Facilitate Percutaneous Endoscopic Cervical Discectomy Via Anterior Transcorporeal Approach for Cervical Intervertebral Disc Herniation.

BACKGROUND: Currently, anterior transdiscal access and posterior interlaminar approach are the main approaches for percutaneous endoscopic cervical discectomy (PECD). To overcome access shortcomings, we previously described a novel anterior endoscopic transcorporeal approach on a migrated cervical disc. We innovatively introduced bone wax into endoscopic surgery to aid hemostasis and facilitate the process of drilling an intracorporeal tunnel. METHODS: Five patients with cervical intervertebral disc herniation (CIDH) were treated by PECD via the anterior transcorporeal approach. During the operation, we marked the punctured tunnel with bone wax containing indigo carmine as a guide and smeared bone wax on the endoscopic burr to aid hemostasis. RESULTS: A satisfactory clinical outcome was observed in all 5 patients postoperatively; pain and neurologic condition were dramatically improved. Surgery-related complications, such as esophageal injury, vascular rupture, hematoma, intervertebral disc infection, or postoperative headache, were not encountered. A computed tomography scan was used to observe the process of bone healing. At 3-month postoperative follow-up, the bone defect within the drilling tunnel had partially shrank and was completely healed at 6 months postoperatively. CONCLUSIONS: The anterior endoscopic transcorporeal approach for PECD is a novel, valuable alternative for the treatment of CIDH. Bone wax could indeed facilitate the operation by guiding the drilling process and instantly controlling the bleeding without obvious interference with bone healing. Long-term follow-up is warranted in further clinical studies.

Percutaneous Endoscopic Retrieval of Intraspinal Cement Leakage: Technical Note.

OBJECTIVE: We sought to preliminarily explore the efficacy and safety of percutaneous endoscopic spinal surgery for epidural cement leakage. We report a case series of patients who underwent percutaneous retrieval of leaked epidural cement and achieved spinal decompression under endoscopy. METHODS: Five patients with neurologic impairment due to epidural cement leakage after percutaneous vertebroplasty were treated with percutaneous endoscopic spinal decompression. Computed tomography reconstruction and 3-dimensional imaging were used to evaluate the extruded material. During follow-up at 3, 6, and 12 months postoperatively, all patients were advised to undergo plain radiograph and computed tomography examinations. RESULTS: The leaked epidural cement was successfully removed in all patients under percutaneous endoscopy through a unilateral or bilateral approach. At the 12-month follow-up, the visual analog scale score of all patients improved. In addition, the neurologic function of each patient improved to at least 1 grade level, as evaluated using the American Spinal Injury Association. According to the modified MacNab criteria, 2 patients had excellent recovery, whereas the other 3 patients had good recovery. CONCLUSIONS: We described a novel and minimally invasive procedure to ameliorate intractable epidural cement extrusion. As an alternative to conventional laminectomy, percutaneous endoscopic retrieval achieved the targeted decompression without damaging the posterior lamina. Moreover, the whole operation was performed under regional anesthesia accompanied with dexmedetomidine sedation, allowed real-time neural function evaluation, and had lower risks of anesthesia-related complications, compared with general anesthesia.

Knockdown of Bone Morphogenetic Proteins Type 1a Receptor (BMPR1a) in Breast Cancer Cells Protects Bone from Breast Cancer-Induced Osteolysis by Suppressing RANKL Expression.

BACKGROUND/AIMS: Bone morphogenetic proteins (BMPs) and BMP receptors widely participate in osteolytic metastasis of breast cancer, while their role in tumor-stromal interaction is largely unknown. In this study, we investigated whether BMP receptor type 1a (BMPR1a) can alter the interaction between metastatic cancer cells and osteoclast precursors. METHODS: Adenovirus-mediated RNA interference was used to interrupt target genes of human breast cancer cell lines and nude mice were injected intratibially with the cancer cells. Tumor-bearing mice were examined by bioluminescence imaging and microCT. Sections of metastatic legs were measured by a series of staining methods. Murine bone marrow mononuclear cells or RAW264.7 cells were cultured with conditioned media of breast cancer cells. RT-PCR, Western blotting and ELISA were used to test mRNA and protein expressions of target molecules. RESULTS: Expression of BMPR1a of MDA-MB-231-luc cells at tumor-bone interface was apparently stronger than that of cancer cells distant from the interface. Mice injected with BMPR1a-knockdown MDA-MB-231-luc cells showed reduced tumor growth and bone destruction compared with control groups. Knockdown (KD) of BMPR1a of MDA-MB-231-luc cells or MCF-7 cells decreased the level of receptor activator for NF-κB ligand (RANKL). Level of RANKL in MDA-MB-231-luc cells or MCF-7 cells was reduced by p38 inhibitor. Compared with control group, knockdown of p38 of breast cancer cells decreased cancer-induced osteoclastogenesis. CONCLUSION: Knockdown of BMPR1a of breast cancer cells suppresses their production of RANKL via p38 pathway and inhibits cancer-induced osteoclastogenesis, which indicates that BMPR1a might be a possible target in breast cancer-induced osteolytic metastasis.

Foraminoplasty at the Tip or Base of the Superior Articular Process for Lateral Recess Stenosis in Percutaneous Endoscopic Lumbar Discectomy: A Multicenter, Retrospective, Controlled Study with 2-Year Follow-Up.

OBJECTIVE: To compare the clinical efficacy and complications which obtained foraminoplasty at the tip or base of the superior articular process (SAP) for the patients with lateral recess stenosis treated by percutaneous endoscopic lumbar discectomy (PELD). METHODS: Between January 2015 and January 2016, 156 patients of lumbar disc herniation accompanying with lateral recess stenosis were treated with PELD in five tertiary hospitals and fulfilled the 2-year follow-up. Among them, 78 patients obtained a foraminoplasty at the tip of SAP (group A), and foraminoplasty at the base of SAP was performed in the other 78 cases (group B). Clinical efficacy was evaluated using the visual analog scale (VAS) score for back and leg pain, Oswestry Disability Index (ODI), and 36-item Short-Form Health Survey (SF-36) score. The intervals of follow-up were scheduled at 1 month, 3 months, 6 months, 1 year, and 2 years after surgery. RESULTS: Mean operative duration is shorter in group B (55 versus 61 min, P = 0.047). Only one case belonged to group A could not tolerate the neural irritation and required conversion to an open procedure. During the surgery, no dura tears, cauda equina syndrome, or infections were observed. 5 patients experienced transient dysesthesia located at the exiting nerve in group A, while no cases complained dysesthesia in group B. 2 cases who suffered temporary motor weakness all belonged to group A. A total of 5 cases obtained a revision surgery after recurrence in the follow-up, in which 3 patients belonged to group A. Compared to the preoperative data, significant improvements in VAS scores of low back pain and sciatica, ODI, and SF-36 PCS and MC were observed in the follow-up, respectively (P < 0.05, respectively). However, no statistical difference was observed at all time-points after surgery between these two groups (P > 0.05, respectively). CONCLUSIONS: For the patients of LDH accompanying with lateral recess stenosis, compared with the routine foraminoplasty at the tip of SAP, our modified foraminoplastic technique does not only change place of foraminoplasty to the base of SAP but also simplified puncture process in transforaminal PELD. Although there was no significant difference in symptom relief, the modified foraminoplasty showed the advantages in decreasing the incidence of postoperative neural dysfunction and reducing operation time.