Radiographic and clinical outcomes following MIS-TLIF in patients with adult lumbar degenerative scoliosis

Abstract Background Patients suffering from adult lumbar degenerative scoliosis (ALDS) are commonly complicated with advanced age, osteoporosis, cardiopulmonary insufficiency, and some other medical comorbidity. Therefore, the traditional open surgery can lead to high rate of postoperative complications. The purposes of this study were to introduce our experiences and explore the efficacy and feasibility of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) in the treatment of patients with ALDS. Methods From January 2008 to January 2014, a retrospective study of 22 patients with ALDS treated with MIS-TLIF was followed up at least 2 years. All patients suffered from one-level lumbar stenosis, and the nerve root block was performed to make sure the exact level. The clinical and radiographic outcomes were evaluated preoperatively and at the time of 2-year follow-up. Results The mean visual analog scale (VAS) back pain scores decreased from 6.2 ± 1.8 preoperatively to 2.2 ± 0.7 at 2-year follow-up (P < 0.05), and the mean VAS leg pain scores decreased from 8.2 ± 0.7 preoperatively to 1.4 ± 1.4 at 2-year follow-up (P < 0.05). The Oswestry Disability Index score improved from 62.4 ± 16.1% preoperatively to 24.2 ± 9.3% at 2-year follow-up (P < 0.05). The average lumbar curve was 20.7° ± 7.0° preoperatively and 12.7° ± 7.1° at 2-year follow-up (P < 0.05). The lumbar lordosis changed from − 39.5° ± 13.6° to − 43.6° ± 10.6° at 2-year follow-up (P < 0.05). Solid fusion was achieved in all patients. Conclusion The technique of MIS-TLIF can be used to treat the patients with ALDS whose symptom is mainly from one-level lumbar stenosis, achieving favorable clinical outcomes and good fusion, with less blood loss and complications

Modulation of fracture healing by senescence-associated secretory phenotype (SASP): a narrative review of the current literature

The senescence-associated secretory phenotype (SASP) is a generic term for the secretion of cytokines, such as pro-inflammatory factors and proteases. It is a crucial feature of senescent cells. SASP factors induce tissue remodeling and immune cell recruitment. Previous studies have focused on the beneficial role of SASP during embryonic development, wound healing, tissue healing in general, immunoregulation properties, and cancer. However, some recent studies have identified several negative effects of SASP on fracture healing. Senolytics is a drug that selectively eliminates senescent cells. Senolytics can inhibit the function of senescent cells and SASP, which has been found to have positive effects on a variety of aging-related diseases. At the same time, recent data suggest that removing senescent cells may promote fracture healing. Here, we reviewed the latest research progress about SASP and illustrated the inflammatory response and the influence of SASP on fracture healing. This review aims to understand the role of SASP in fracture healing, aiming to provide an important clinical prevention and treatment strategy for fracture. Clinical trials of some senolytics agents are underway and are expected to clarify the effectiveness of their targeted therapy in the clinic in the future. Meanwhile, the adverse effects of this treatment method still need further study

Injectable biocomposites for bone healing in rabbit femoral condyle defects.

A novel biomimetic bone scaffold was successfully prepared in this study, which was composed of calcium sulfate hemihydrate (CSH), collagen and nano-hydroxyapatite (nHAC). CSH/nHAC was prepared and observed with scanning electron microscope and rhBMP-2 was introduced into CSH/nHAC. The released protein content from the scaffold was detected using high performance liquid chromatography at predetermined time interval. In vivo bone formation capacity was investigated by means of implanting the scaffolds with rhBMP-2 or without rhBMP-2 respectively into a critical size defect model in the femoral condyle of rabbit. The releasing character of rhBMP-2 was that an initial burst release (37.5%) was observed in the first day, followed by a sustained release and reached 100% at the end of day 20. The CSH/nHAC showed a gradual decrease in degradation with the content of nHAC increase. The results of X-rays, Micro CT and histological observation indicated that more new bone was formed in rhBMP-2 group. The results implied that this new injectable bone scaffold should be very promising for bone repair and has a great potential in bone tissue engineering

Dual-band valley-protected topological edge states in graphene-like phononic crystals with waveguide

Since valley was introduced into phononic crystals, it has promoted far-reaching developments in topologically protected acoustic transmission. However, in the novel research field of valley-Hall phononic topological insulators, most researchers only focus on valley-protected edge state with a single working frequency band. Here, we demonstrate dual-band valley-protected topological edge states in a graphene-like two-dimensional phononic crystal, which consists of columnar air cavities and rigid scatters. It is demonstrated that energy band inversion happens and a gap can be opened at the two Dirac cones at the K (K') symmetry points of the Brillouin zone by tuning the radius differences between adjacent columnar air cavities. In addition, we demonstrate the presence of dual-band topologically protected edge states with properties like suppressed back-scattering, one-way transmission, and sharp bend resistance. In these contexts, beam splitting with dual-band is achieved by combining valley vortex states with opposite chirality. Our work may provide a practical method for solving high-efficiency and high-capacity multi-channel acoustic communication in fluid media

Biomechanical effect of proximal multifidus injury on adjacent segments during posterior lumbar interbody fusion: a finite element study

Abstract Background Adjacent segment degeneration (ASD) is a common complication of lumbar interbody fusion; the paraspinal muscles significantly maintain spinal biomechanical stability. This study aims to investigate the biomechanical effects of proximal multifidus injury on adjacent segments during posterior lumbar interbody fusion (PLIF). Methods Data from a lumbosacral vertebral computed tomography scan of a healthy adult male volunteer were used to establish a normal lumbosacral vertebral finite element model and load the muscle force of the multifidus. A normal model, an L4/5 PLIF model (PFM) based on a preserved proximal multifidus, a total laminectomy PLIF model (TLPFM), and a hemi-laminectomy PLIF model based on a severed proximal multifidus were established, respectively. The range of motion (ROM) and maximum von Mises stress of the upper and lower adjacent segments were analyzed along with the total work of the multifidus muscle force. Results This model verified that the ROMs of all segments with four degrees of freedom were similar to those obtained in previous research data, which validated the model. PLIF resulted in an increased ROM and maximum von Mises stress in the upper and lower adjacent segments. The ROM and maximum von Mises stress in the TLPFM were most evident in the upper adjacent segment, except for lateral bending. The ROM of the lower adjacent segment increased most significantly in the PFM in flexion and extension and increased most significantly in the TLPFM in lateral bending and axial rotation, whereas the maximum von Mises stress of the lower adjacent segment increased the most in the TLPFM, except in flexion. The muscle force and work of the multifidus were the greatest in the TLPFM. Conclusions PLIF increased the ROM and maximum von Mises stress in adjacent cranial segments. The preservation of the proximal multifidus muscle contributes to the maintenance of the physiological mechanical behavior of adjacent segments, thus preventing the occurrence and development of ASD

Minimally invasive unilateral pedicle screws and a translaminar facet screw fixation and interbody fusion for treatment of single-segment lower lumbar vertebral disease: surgical technique and preliminary clinical results

Abstract Background Conventional open transforaminal lumbar interbody fusion (TLIF) using unilateral pedicle screws and a translaminar facet screw has been performed for many years with good results. The outcomes of minimally invasive TLIF (MIS TLIF) are similar to the good outcomes of open TLIF, with the additional benefits of reducing iatrogenic injury, shortening hospital stays, and reducing the recovery duration. Instead of using small cuts on both sides, we performed MIS TLIF through a single cut using unilateral pedicle screws and a translaminar facet screw. The operative feasibility, efficacy safety, and benefits of single-level MIS TLIF of such techniques require further clarification. Methods A total of 60 patients with various single-segment lower lumbar vertebral diseases were treated in our department from January 2010 to March 2013. All the patients were initially performed single-level MIS TLIF using a hybrid construction of unilateral pedicle screws and a translaminar facet screw. Patient demographics and operative data were collected. The clinical outcomes were assessed before surgery and 3, 6, 12, and 24 months after surgery using the visual analog scale (VAS) for back and leg pain and the Oswestry Disability Index (ODI). Radiologic assessment of the lumbar spine with static and dynamic plain radiographs was performed 3, 6, 12, and 24 months after surgery. The fusion rates were assessed by an independent radiologist 2 years after surgery according to the Bridwell interbody fusion grading system. Results No patients experienced significant postoperative complications. Excepting two cases, 58 cases were followed up for 24–38 months, averaged 29.9 ± 4.1 months. The patients’ average age was 46.6 ± 11.5 years, operative time 109.7 ± 17.8 min, intraoperative blood loss 67.3 ± 29.7 ml, length of incision 29.0 ± 3.2 mm, fluoroscopy time 31.1 ± 7.2 s, time to ambulation 20.3 ± 7.0 h, length of hospital stay 5.1 ± 1.1 days, and length of the translaminar facet screw 51.7 ± 3.4 mm. Screw position results: type I, 54 cases with 54 segments; type II, four cases with four segments. There were two (3.4%) translaminar facet screw failures, which were intraoperatively converted to a bilateral pedicle screw fixation procedure and excluded from the research. The postoperative images showed good positioning of the hybrid internal fixation, and all of the translaminar facet screws penetrated the facet joint. Two (3.6%) translaminar facet screws penetrated the lateral lamina and two (3.6%) translaminar facet screws penetrated the medial lamina without any serious neural complications. During the follow-up, there was no screw loosening or pedicle fracture observed. The VAS and ODI scores were significantly improved compared with the preoperative scores (P < 0.05), and the symptoms disappeared gradually. Fifty-one patients (87.9%) achieved grade I fusion radiographically at the final follow-up. Conclusions MIS TLIF using a hybrid construction of unilateral pedicle screws and a translaminar facet screw is safe and effective in the treatment of single-segment lower lumbar vertebral disease, and it can be used as an optimal choice for fixation and fusion of some single-segment lower lumbar vertebral diseases

Macroscopic appearance of femoral condyle bone defect (A); Defects were implanted with bone scaffolds (B); the appearance of the surgery site after operation (C).

<p>Macroscopic appearance of femoral condyle bone defect (A); Defects were implanted with bone scaffolds (B); the appearance of the surgery site after operation (C).</p