Surgical treatment of thoracolumbar fracture in ankylosing spondylitis: A comparison of percutaneous and open techniques.

BACKGROUND CONTEXT: Posterior percutaneous long-segment internal fixation and open fixation with long-segment screws have been used to treat thoracolumbar fractures in ankylosing spondylitis patients. PURPOSE: To observe the clinical effect of posterior percutaneous long-segment internal fixation in 26 ankylosing spondylitis (AS) patients with thoracolumbar fractures. STUDY DESIGN: Retrospective cohort study. PATIENT SAMPLE: Forty-seven AS patients who were diagnosed with thoracolumbar fractures and treated from December 2014 to December 2018. OUTCOME MEASURES: Visual analog scale score, Cobb angle, American Spinal Injury Association Grade, SF-Qualiveen score, pedicle screw misplacement rate, operative duration, blood loss, complications, bed rest duration and modified MacNab score. METHODS: All patients were divided into the percutaneous group (PG) and the open group. Twenty-six patients were treated with percutaneous long-segment internal fixation, and the remaining 21 underwent open fixation with long-segment screws. The minimum follow-up period was 12 months. RESULTS: The operations were successful in both groups. A patient in the PG showed class C wound healing, while the others showed class A healing, and some patients experienced perioperative complications. All patients were followed up for 12-48 months (mean, 33.81 months), and all patients showed clinical osseous fracture healing. Significant differences were found in operative duration, intraoperative blood loss and postoperative bed rest duration between the two groups (P < 0.05). No significant difference was found in improvement of the visual analog scale score, Cobb angle of spinal kyphosis or neurological function after the operation (P > 0.05). CONCLUSIONS: As a minimally invasive procedure, posterior percutaneous long-segment internal fixation requires less time, results in less blood loss and causes less trauma. This procedure can also improve patients' pain, neurological function and kyphotic deformity and achieve effects similar to those of traditional methods. With this curative clinical effect, this procedure can be used as an ideal surgical treatment for thoracolumbar fractures in AS patients, especially for elderly patients with underlying diseases and high surgical risk.

Naringin protects human nucleus pulposus cells against TNF-α-induced inflammation, oxidative stress, and loss of cellular homeostasis by enhancing autophagic flux via AMPK/SIRT1 activation.

Activation of the proinflammatory-associated cytokine, tumor necrosis factor-α (TNF-α), in nucleus pulposus (NP) cells is essential for the pathogenesis of intervertebral disc degeneration (IDD). Restoring autophagic flux has been shown to effectively protect against IDD and is a potential target for treatment. The goal of this study was to explore particular autophagic signalings responsible for the protective effects of naringin, a known autophagy activator, on human NP cells. The results showed that significantly increased autophagic flux was observed in NP cells treated with naringin, with pronounced decreases in the inflammatory response and oxidative stress, which rescued the disturbed cellular homeostasis induced by TNF-α activation. Autophagic flux inhibition was detectable in NP cells cotreated with 3-methyladenine (3-MA, an autophagy inhibitor), partially offsetting naringin-induced beneficial effects. Naringin promoted the expressions of autophagy-associated markers via SIRT1 (silent information regulator-1) activation by AMPK (AMP-activated protein kinase) phosphorylation. Either AMPK inhibition by BML-275 or SIRT1 silencing partially counteracted naringin-induced autophagic flux enhancement. These findings indicate that naringin boosts autophagic flux through SIRT1 upregulation via AMPK activation, thus protecting NP cells against inflammatory response, oxidative stress, and impaired cellular homeostasis. Naringin can be a promising inducer of restoration autophagic flux restoration for IDD.

Circ_0001721 enhances doxorubicin resistance and promotes tumorigenesis in osteosarcoma through miR-758/TCF4 axis.

BACKGROUND: Osteosarcoma (OS) is a common type of bone malignancy that often occurs in children and adolescents. Chemoresistance is a huge barrier to cancer therapy. This study aimed to investigate the role and potential mechanism of circ_0001721 in doxorubicin (DXR) resistance and OS development. METHODS: The levels of circ_0001721, miR-758 and transcription factor 4 (TCF4) were detected by quantitative real-time polymerase chain reaction or western blot assay. Cell Counting Kit-8 (CCK-8) assay was used to calculate the half inhibition concentration (IC50) of DXR and assess cell viability. Cell migration and invasion were evaluated by transwell assay. Cell apoptosis was monitored by flow cytometry. The levels of multidrug resistance-related and Wnt/ß-catenin pathway-related proteins were measured by western blot assay. The interaction among circ_0001721, miR-758 and TCF4 were confirmed by dual-luciferase reporter assay, RNA immunoprecipitation assay or RNA pull-down assay. The xenograft model was established to analyze tumor growth in vivo. RESULTS: Circ_0001721 and TCF4 were upregulated, whereas miR-758 was down-regulated in DXR-resistant OS tissues and cells. Circ_0001721 silence reduced DXR resistance of KHOS/DXR and MG63/DXR cells. Circ_0001721 regulated DXR resistance via sponging miR-758. Moreover, miR-758 modulated DXR resistance by targeting TCF4. Besides, circ_0001721 knockdown inhibited tumor growth in vivo. CONCLUSION: Circ_0001721 potentiated DXR resistance and facilitated the progression of OS by regulating miR-758/TCF4 axis, which provides promising therapeutic targets for OS treatment.

The importance of preoperative T1 slope for determining proper postoperative C2-7 Cobb's angle in patients undergoing cervical reconstruction.

BACKGROUND: This study aimed to explore the relationship among different cervical sagittal parameters in asymptomatic volunteers and the correlation between surgical efficacy and difference of presumed and actual postoperative C2-7 Cobbs's angle (C2-7COBB), which was calculated based on preoperative T1 slope (T1S) in patients undergoing cervical reconstruction. METHODS: In total, 158 inpatients with cervical spondylosis and 274 asymptomatic volunteers were retrospectively reviewed. Cervical sagittal parameters, such as C2-7COBB, T1S, thoracic inlet angle (TIA), and neck tilt (NT), were compared. Then, the correlation among these parameters was analyzed in asymptomatic volunteers, and a regression equation between T1S and C2-7COBB was established and used to analyze the correlation among the Japanese Orthopaedic Association (JOA) score improvement, the sagittal parameters, and the difference between presumed and actual postoperative C2-7COBB in patients after cervical reconstruction. RESULTS: The mean T1S, C2-7COBB, and TIA were significantly decreased in patients (P < 0.01). T1S and NT had a strong correlation with TIA (P < 0.01). T1S demonstrated a moderate correlation with C2-7COBB in asymptomatic volunteers (r = 0.569, P < 0.01). A regression equation had been established as C2-7COBB = 0.742 × T1S - 0.866. The mean C2-7COBB and JOA score improved significantly (P < 0.05) postoperatively. Moreover, the JOA improvement rate showed a significant negative correlation with the difference in the presumed and actual postoperative C2-7COBB (r = - 0.696, P < 0.01). CONCLUSION: Our study successfully established a regression equation for calculating postsurgical C2-7COBB based on the correlation between T1S and C2-7COBB in asymptomatic volunteers. The regression equation could be used for guiding surgeons to accomplish an ideal postsurgical C2-7COBB for patients with cervical spondylosis.

Worldwide research productivity in fracture surgery: A 10-year survey of publication activity.

Worldwide research contributions have allowed the field of fracture surgery to progress. However, to the best of our knowledge, no studies have documented the main characteristics of publications from different countries. The present study aimed to determine the quantity and quality of worldwide research in fracture surgery. The Web of Science database was searched to identify fracture articles published between 2005 and 2014. The contributions of countries were evaluated based on paper and citation numbers, and the research output of each country was adjusted according to population size. A total of 19,423 papers on the topic of fracture surgery were identified worldwide, and the total number of publications from 2005 to 2014 had significantly increased by 1.82-fold (P<0.001). The majority of papers (86.64%) were published by high-income countries (gross national income per capita ≥$12,736), 13.25% by middle-income countries ($1,046-12,735) and 0.11% by low-income countries (≤$1,045). The United States contributed the highest number of publications (33.34%), followed by the United Kingdom (9.03%), Germany (8.42%), China (5.58%) and Japan (4.18%). Furthermore, the United States ranked first according to total citations (72,640). Articles from Sweden achieved the highest average citations per paper (15.63), followed by Australia (12.84) and Canada (12.44). When the number of publications were adjusted for population size, Switzerland was the first (56.39), followed by Austria (35.43) and the Netherlands (30.68). In conclusion, the number of publications in fracture surgery increased from 2005 to 2014, and the majority of fracture papers were published by high-income countries, while few papers were published by low-income countries. The United States was the most prolific country, but based on population size, a number of smaller countries in Europe may be relatively more prolific.

Treatment of Xanthelasma Palpebrarum With Intralesional Pingyangmycin.

BACKGROUND: Xanthelasma palpebrarum (xanthelasma) is the most common type of cutaneous xanthoma, and many patients tend to seek medical treatments for cosmetic reasons. Many methods treating xanthelasma have been proposed, but none of these options can be regarded as a perfect solution. OBJECTIVE: To study and evaluate the intralesional injection treatment of xanthelasma with pingyangmycin, which has been widely used as a broad-spectrum antitumor antibiotic. MATERIALS AND METHODS: 21 lesions in 12 patients were treated by intralesional pingyangmycin. Photographs were taken before and after each treatment session. Patients were followed up for 7 to 36 months. RESULTS: All patients except one received satisfactory results after up to 2 sessions. Only 1 patient had a local recurrence 1 year after the treatment. No severe complications such as infection, atrophy, ulceration, or scar were noticed. CONCLUSION: Intralesional pingyangmycin is a cheap, effective, and safe treatment for xanthelasma, which has been well accepted by patients.

New Posterior Atlantoaxial Restricted Non-Fusion Fixation for Atlantoaxial Instability: A Biomechanical Study.

BACKGROUND: Loss of axial rotation and lateral bending after atlantoaxial fusion reduces a patient's quality of life. Therefore, effective, nonfusion fixation alternatives are needed for atlantoaxial instability. OBJECTIVE: To evaluate the initial stability and function of posterior atlantoaxial restricted nonfusion fixation (PAARNF), a new protocol, using cadaveric cervical spines compared with the intact state, destabilization, and posterior C1-C2 rod fixation. METHODS: Cervical areas C0 through C3 were used from 6 cadaveric spines to test flexion-extension, lateral bending, and axial rotation range of motion (ROM). With the use of a machine, 1.5-Nm torque at a rate of 0.1 Nm/s was used and held for 10 seconds. The specimens were loaded 3 times, and data were collected in the third cycle and tested in the following sequence: (1) intact, (2) destabilization (using a type II odontoid fracture model), (3) destabilization with PAARNF (PAARNF group), and (4) rod implantation (rod group). The order of tests for the PAARNF and rod groups was randomly assigned. RESULTS: The average flexion-extension ROM in the PAARNF group was 7.44 ± 2.05°, which was significantly less than in the intact (P = .00) and destabilization (P = .00) groups but not significantly different from that of the rod group (P = .07). The average lateral bending ROM (10.59 ± 2.33°; P = .00) and axial rotation ROM (38.79 ± 13.41°; P = .00) of the PAARNF group were significantly greater than in the rod group. However, the values of the PAARNF group showed no significant differences compared with those of the intact group. CONCLUSION: PAARNF restricted atlantoaxial flexion-extension but preserved axial rotation and lateral bending at the atlantoaxial joint in a type II odontoid fracture model. However, it should not be used clinically until further studies have been performed to test the long-term effects of this procedure.

Subaxial Cervical Intradiscal Pressure and Segmental Kinematics Following Atlantoaxial Fixation in Different Angles.

OBJECTIVE: To evaluate in a comprehensive biomechanical study the influences of fixed C1-C2 and different C1-C2 angles on the range of motion (ROM) and the intradiscal pressure (IDP) of subaxial cervical spine. METHODS: We simulated three-dimensional cervical motions on 8 human specimens with C1-C2 fixed in 3 different angles (neutral position, neutral position -10°, neutral position +10°) following intact analysis in the material test system. The ROM changes of each motion segment and the IDP changes of 4 subaxial motion segments (C2-C3, C3-C4, C4-C5, and C5-C6) were monitored. RESULTS: ROM change patterns at all subaxial segments were similar. Fixed C1-C2 led to a significant ROM increase relative to the intact condition during flexion/extension testing. A larger C1-C2 angle (neutral position +10°) caused an additional ROM increase during flexion, whereas a smaller C1-C2 angle (neutral position -10°) induced a further ROM increase during extension. Axial rotation testing revealed the most striking and similar ROM increases in the instrumented groups relative to the intact group. Lateral bending testing did not reveal significant ROM change between the instrumented groups and the intact group. For IDP analysis, C1-C2 fixed in a larger angle (neutral position +10°) caused significant IDP increases at the C2-C3, C3-C4, and C4-C5 levels during flexion. CONCLUSIONS: To maintain a physiologic sagittal alignment of subaxial cervical spine, C1-C2 should be fixed in the neutral position or a relatively smaller angle instead of a more lordotic position.

Effects of RNA interference-mediated knockdown of livin and survivin using monomethoxypolyethylene glycol-chitosan nanoparticles in MG-63 osteosarcoma cells.

MG-63 human osteosarcoma cells were transfected with short hairpin RNA (shRNA) against livin and survivin using monomethoxypolyethylene glycol­chitosan (mPEG­CS) nanoparticles (NPs) as carriers, with the aim of evaluating the effect on cell proliferation and apoptosis. mPEG­CS NPs sized ~100 nm were prepared by ionic crosslinking. mPEG­CS­livin shRNA, mPEG­CS­survivin shRNA and mPEG­CS­(livin shRNA + survivin shRNA) NPs were constructed by electrostatic adsorption at NP suspension/gene solution ratios of 3:1 to transfect MG­63 cells. The expression levels of livin and survivin mRNA and protein were measured by reverse transcription­polymerase chain reaction and western blotting, respectively. The inhibitory effects of downregulated livin and survivin expression on cell proliferation were measured using an MTT assay. The apoptosis­inducing effects of livin and surivin knockdown were investigated using a Hoechst staining kit. All shRNA groups resulted in reduced expression of livin and survivin mRNA and protein in MG­63 cells. The MTT assay and Hoechst staining indicated that simultaneous knockdown of livin and survivin genes inhibited the proliferation of MG­63 cells and promoted their apoptosis, to a greater extent than knocking down either gene individually. The simultaneous interference mediated by mPEG­CS NPs significantly reduced livin and survivin expression in MG­63 cells, suppressed proliferation and facilitated apoptosis, to a greater extent than knockdown of either livin or survivin alone were. Thus the results indicate a synergistic effect of livin and survivin.

Glucocorticoid induced osteoblast apoptosis by increasing E4BP4 expression via up-regulation of Bim.

It is well known that glucocorticoid (GC)-induced bone loss is caused primarily by hypofunction and apoptosis of osteoblasts. However, the precise molecular events underlying the effect of GC on osteoblast apoptosis are not fully understood. Recent studies implicated an important role of E4BP4 in the regulation of osteoblast apoptosis and differentiation. Furthermore, E4BP4 is a GC-regulated gene required for GC-induced apoptosis in many cells. Therefore, we hypothesize that E4BP4 may be implicated in the process of GC-induced osteoblast apoptosis. Western blot, reverse-transcription-PCR, flow cytometry, and Hoechst 33258 staining were employed to investigate the role of E4BP4 in dexamethasone (DEX)-induced osteoblast apoptosis. We found that the expression of E4BP4 is significantly up-regulated in osteoblasts exposed to DEX. Furthermore, the depletion of E4BP4 significantly decreased DEX-induced osteoblast apoptosis. In addition, E4BP4 plays a crucial role in GC-evoked apoptosis of osteoblasts by enabling induction of Bim. On the basis of these results above, we can draw the conclusion that E4BP4 may contribute to the process of DEX-induced osteoblast apoptosis.

Can intermuscular cleavage planes provide proper transverse screw angle? Comparison of two paraspinal approaches.

PURPOSE: The goal of this study was to determine which paraspinal approach provided a better transverse screw angle (TSA) for each vertebral level in lower lumbar surgery. METHODS: Axial computed tomography (CT) images of 100 patients, from L3 to S1, were used to measure the angulation parameters, including transverse pedicle angle (TPA) and transverse cleavage plane angle (TCPA) of entry from the two approaches. The difference value between TCPA and TPA, defined as difference angle (DA), was calculated. Statistical differences of DA obtained by the two approaches and the angulation parameters between sexes, and the correlation between each angulation parameter and age or body mass index (BMI) were analyzed. RESULTS: TPA ranged from about 16° at L3 to 30° at S1. TCPA through the Wiltse's and Weaver's approach ranged from about -10° and 25° at L3 to 12° and 32° at S1, respectively. The absolute values of DA through the Weaver's approach were significantly lower than those through the Wiltse's approach at each level. The angulation parameters showed no significant difference with sex and no significant correlation with age or BMI. CONCLUSIONS: In the lower lumbar vertebrae (L3-L5) and S1, pedicle screw placement through the Weaver's approach may more easily yield the preferred TSA consistent with TPA than that through the Wiltse's approach. The reference values obtained in this paper may be applied regardless of sex, age or BMI and the descriptive statistical results may be used as references for applying the two paraspinal approaches.

Clinical and radiological outcomes of spinal cord injury without radiologic evidence of trauma with cervical disc herniation.

PURPOSE: To verify the relationship between neurologic deficit after spinal cord injury without radiologic evidence of trauma (SCIWORET) and coexisting cervical disc herniation (CDH). METHODS: A retrospective review was made to compare the neurologic and radiological outcomes in SCIWORET patients with and without CDH. The neurologic deficit was evaluated by the American Spinal Injury Association (ASIA) scale at admission and last follow-up. The radiological evaluation was performed with magnetic resonance imaging to determine the maximum canal compromise (MCC) and maximum spinal cord compression (MSCC). RESULTS: Prevalence of CDH was 37.1 % among all 70 SCIWORET cases. There was no significant difference between the CDH and non-CDH group in the ASIA grade at admission and last follow-up and the improvement. Patients with CDH had more substantial MSCC (P < 0.05) but not MCC than those without CDH. No significant correlation was noted between the extent of MSCC or MCC and the initial and final neurologic functions. 12 of 26 patients with CDH underwent anterior cervical discectomy fusion, while the remaining 14 received anterior cervical corpectomy fusion. No significant difference was noted in the neurologic outcomes between the two techniques. CONCLUSIONS: CDH in most patients with SCIWORET likely occurred before rather than after trauma. CDH caused more severe cord compression but did not aggravate the neurologic injury. The extent of MSCC had no association with the initial neurologic deficit or final recovery.

[Treatment and short-term effect analysis of Pipkin fracture].

OBJECTIVE: To summarize the treatment method and to analyze short-term therapeutic effect of Pipkin fracture. METHODS: From January 2002 to January 2007, 14 cases of Pipkin fracture were treated. There were 10 males and 4 females with an average of 33.5 years (ranged from 28 to 52 years). Fractures were caused by traffic accident. According to Pipkin's classification, there were 4 cases of type I, 6 cases of type II, 2 cases of type III and 2 cases of type IV. The time from injury to operation was 24 hours to 8 weeks. All patients received open reduction under Kocher-Langenbeck approach, ameliorative posterior-lateral approach or combined approaches. Absorbable screws and suture line internal fixation were performed in fracture of the femoral head, titanium cannulated screws were used to fix the femoral intertrochanteric fracture in type III, and acetabular tridimensional memory fixation systems were used to fix the posterior acetabular fracture in type IV. RESULTS: All cases had one-stage wound healing, no complications of deep infection and thrombosis of deep vein of lower limb occurred. All the patients were followed up for 12-48 months (mean 26 months). One case of type III fracture for Pipkin had necrosis of femoral head after 1 year of reduction and fixation, and received total hip replacement; other patients achieved bony healing after 6-10 months (mean 8 months). According to D'Aubigne-Postel score, the results were excellent in 5 cases, good in 6 cases, fair in 2 cases and poor in 1 case; the excellent and good rate was 78.6%. CONCLUSION: It is important for the patients with Pipkin fracture to early diagnose, to select proper operation approach, to stably fix fracture and to manage after operation in reducing complication and recovering hip joint function.

[Reconstruction of condyle in treatment of refractory condylar nonunion and defect of humerus].

OBJECTIVE: To discuss the strategy of condylar reconstruction in the treatment of refractory condylar nonunion and defect of humerus. METHODS: From September 1998 to September 2005, 18 patients with refractory condylar nonunion concomitant withdefect of humerus were treated. The series included 12 males and 6 females, aged 18 to 60 years. According to AO/ASIF system, primal fractures were classified, including 5 cases of type A3, 2 cases of type B1, 4 cases of type C2 and 7 cases of type C3 fractures. Condylar nonunion and defect of humerus were confirmed by preoperative X-ray. Defective bone mass was 1-4 cm2. The mean extension and flexion of elbow joint was 21.5 degrees (5-65 degrees) and 95.8 degrees (85.0-123.5 degrees) respectively. According to Cassebaum scoring system, the excellent and good rate was 27.8% (excellent in 1 case and good in 4 cases). Time from injury to operation averaged 22.8 months (7-52 months). All patients were operated with approach of olecranon osteotomy. Bone defect was reconstructed with iliac autograft. Shape memory compressive connector, Kirschner wire, cannulated nail, anatomic plates and reconstruction plates were used to fix. RESULTS: Eighteen patients were followed up 12-86 months (mean 27.6 months). All the incisions healed by first intention. No bone block displacement,loosening or breakage of internal fixation occurred. The time of bone union averaged 5.7 months (4-8 months). The mean extension and flexion of elbow joint were 11.4 degrees (0-44.5 degrees) and 128.6 degrees (105.5-144.5 degrees) 1 year after operation. Ectopicossification formed in 1 case at anterior part of elbow 4 months after operation. According to Cassebaum scoring system,the results were excellent in 8 cases, good in 6 cases, fair in 3 cases and poor in 1 case. The excellent and good rate was 77.8%. CONCLUSION: The shape of humeral condyle can be reconstructed with iliac autograft. Compressive internal fixation of bone block can promote bone union. Anatomical reconstruction, rigid internal fixation and early function exercise can improve the function of elbow joint evidently.