Decellularized tendon matrix (DTM) has shown great potential for inducing tenogenic differentiation and facilitating tendon repair. In which, the retained native tendon-derived matrix in DTM is considered as the main factor for these effects. However, whether preservation of the highly aligned architecture of DTM is also essential for tenogenic differentiation and tendon repair has not been well investigated yet. In this study, we prepared aligned DTM (A-DTM), in which the native aligned architecture was preserved and random DTM (R-DTM), in which the native architecture was disrupted. In vitro study indicated that after decellularization procedures, both A- and R-DTM retained most of the tendon extracellular matrix (ECM). In addition, A-DTM exhibited an inherent aligned architecture, whilst, R-DTM showed a random arranged surface topography. Both DTM materials exhibited good biocompatibility for tendon stem/progenitor cells (TSPCs) and adipose stem cells (ASCs). They were able to adhere and proliferate on the DTM materials and maintain high viability. Interestingly, A-DTM promoted longitudinally oriented growth pattern of TSPCs and ASCs, whereas, cells grown on the R-DTM showed a random spreading. Furthermore, both DTM materials induced tenogenic differentiation of TSPCs and ASCs without the addition of any exotic growth factors. However, A-DTM demonstrated a stronger pro-tendon differentiation compared to R-DTM. In vivo study demonstrated that A-DTM combined with TSPCs or ASCs significantly promoted functional repair of injured Achilles tendon while reducing fibrovascular scar and heterotopic ossification (HO) formation. Taken together, these results indicated that aligned architecture of DTM is essential for stem cell tenogenic differentiation and tendon repair. Thus, for the application of DTM, it is very important to preserve its native aligned architecture. In another scenario, when DTM was used to prepared a composite biomaterial, a tendon-mimic topography should be re-constructed.

Objective: The reported date in the repeat surgical intervention for adolescent lumbar disc herniation (ALDH) after percutaneous endoscopic lumbar discectomy (PELD) was quite scarce. This study aims to introduce cases of repeat surgeries after PELD for ALDH and assess the incidence, chief causes, repeat surgery methods, and surgical outcomes of repeat surgeries after PELD for ALDH. Methods: A retrospective multicenter observational study was conducted on patients undergoing repeat surgeries after PELD for ALDH at four tertiary referral hospitals from January 2014 through August 2022. The incidence of repeat surgeries, chief causes, strategies for repeat surgeries, and timing of repeat surgeries were recorded and analyzed. The clinical outcomes were evaluated by the Numeric Rating Scales (NRS) scores and the modified MacNab criteria. Statistical analyses were performed with the Wilcoxon signed-rank test. Results: A total of 23 patients who underwent repeat surgeries after PELD for ALDH were included. The chief causes were re-herniation (homo-lateral re-herniation at the same level, new disc herniation of adjacent level). The repeat surgery methods were revision PELD, micro-endoscopic discectomy (MED), open discectomy and instrumented lumbar inter-body fusion. The NRS scores decreased significantly in follow-up evaluations and these scores demonstrated significant improvement at the last follow-up (p < 0.002). For the modified MacNab criteria, at the last follow-up, 18 patients (78.26%) had an excellent outcome, and the overall success rate was 86.95%. Conclusion: This study's data suggest that young patients who underwent repeat surgery improved significantly compared to baseline. The chief cause was re-herniation. Revision PELD was the main surgical procedure, which provides satisfactory clinical results in young patients who underwent repeat surgeries.

Study Design: Intraoperative neurophysiological monitoring (IONM) as a guide to bone layer estimation was examined during posterior cervical spine lamina grinding. Objective: To explore the feasibility of IONM to estimate bone layer thickness. Summary of Background Data: Cervical laminoplasty is a classic operation for cervical spondylosis. To increase safety and accuracy, surgery-assistant robots are currently being studied. It combines the advantages of various program awareness methods to form a feasible security strategy. In the field of spinal surgery, robots have been successfully used to help place pedicle screws. IONM is used to monitor intraoperative nerve conditions in spinal surgery. This study was designed to explore the feasibility of adding IONM to robot safety strategies. Methods: Chinese miniature pig model was used. Electrodes were placed on the lamina, and the minimum stimulation threshold of DNEP for each lamina was measured (Intact lamina, IL). The laminae were ground to measure the DNEP threshold after incomplete grinding (Inner cortical bone preserved, ICP) and complete grinding (Inner cortical bone grinded, ICG). Subsequently, the lateral cervical mass screw canal drilling was performed, and the t-EMG threshold of the intact and perforated screw canals was measured and compared. Result: The threshold was significantly lower than that of the recommended threshold of DENP via percutaneous cervical laminae measurement. The DNEP threshold decreases with the process of laminae grinding. The DNEP threshold of the IL group was significantly higher than ICP and ICG group, while there was no significant difference between the ICP group and the ICG group. There was no significant relationship between the integrity of the cervical spine lateral mass screw path and t-EMG threshold. Conclusions: It is feasible to use DENP threshold to estimate lamina thickness. Cervical lateral mass screw canals by t-EMG showed no help to evaluate the integrity.

Zinc (Zn) is a bioabsorbable metal that shows great potential as an implant material for orthopedic applications. Suitable concentrations of zinc ions promote osteogenesis, while excess zinc ions cause apoptosis. As a result, the conflicting impacts of Zn2+ concentration on osteogenesis could prove to be significant problems for the creation of novel materials. This study thoroughly examined the cell viability, proliferation, and osteogenic differentiation of rat bone marrow mesenchymal stem cells (rBMSCs) cultured in various concentrations of Zn2+ in vitro and validated the osteogenesis effects of zinc implantation in vivo. The effective promotion of cell survival, proliferation, migration, and osteogenic differentiation of bone marrow mesenchymal stem cell (BMSCs) may be achieved at a low concentration of Zn2+ (125 μM). The excessively high concentration of zinc ions (>250 μM) not only reduces BMSCs' viability and proliferation but also causes them to suffer apoptosis due to the disturbed zinc homeostasis and excessive Zn2+. Moreover, transcriptome sequencing was used to examine the underlying mechanisms of zinc-induced osteogenic differentiation with particular attention paid to the PI3K-AKT and TGF-β pathways. The present investigation elucidated the dual impacts of Zn2+ microenvironments on the osteogenic characteristics of rBMSCs and the associated processes and might offer significant insights for refining the blueprint for zinc-based biomaterials.

Objective:To investigate the hidden blood loss (HBL) and risk factors of uniportal full-endoscopic unilateral laminotomy for bilateral decompression (UFE-ULBD) for patients with lumbar spinal stenosis (LSS).Methods:Patients with single-segment LSS who underwent UFE-ULBD from a single orthopedic center were retrospectively analyzed between Aug.2021 and Jun.2023. The general data of patients such as age, gender, body mass index, history of smoking and drinking, medical comorbidities, preoperative anemia, American Society of Anesthesiologists physical status classification; surgical data such as surgical segment, Schizas classification of spinal stenosis, anesthesia method, operation time, intraoperative crystal fluid/colloid infusion volume; and radiological parameters such as paraspinal muscle ratio, angle of facetectomy, decompression ratio of disc-flava ligament space, decompression ratio of osseous lateral recess, superior articular process interval enlargement ratio, lamina interval enlargement ratio, dural sac cross-sectional area and enlargement ratio were also measured.Results:Fifty-six patients (26 males and 30 females) were retrospectively enrolled in this study. The mean operation time was 97.2±45.2 minutes, the mean total blood loss was 235.0±188.5 ml, and the mean HBL was 190.7±184.3 ml, accounting for 66.1% of total blood loss. These patients were divided into HBL positive group (HBL≥470 ml) and HBL negative group (HBL<470 ml). There were significant differences between the two groups in preoperative bilateral lamina interval (P=0.002), postoperative bilateral lamina interval enlargement ratio (P=0.021), preoperative dural sac cross-sectional area (P=0.009) and postoperative dural sac cross-sectional area enlargement ratio (P=0.013) at the surgical level. Logistic regression analysis suggested postoperative dural sac cross-sectional area enlargement ratio at the surgical level (OR=3.889, P=0.042) was the potential risk of HBL.Conclusions:HBL was significant in LSS patients who underwent UFE-ULBD. And postoperative dural sac cross-sectional area enlargement ratio at the surgical level might be potential risk of HBL.

目前慢性疼痛(chronic pain)被定义为一种疾病,全球众多病人受其困扰,口服镇痛药等常规治疗效果不佳且不良反应大.通过鞘内给药(intrathecal drug delivery,ITDD)技术可将药物注入蛛网膜下腔,通过脑脊液循环直接作用于脑、脊髓而发挥作用,快速、稳定、高效治疗慢性疼痛,同时低药物剂量减少了药物不良反应,改善了病人生活质量及心理状态.本文就当前鞘内给药治疗慢性疼痛的研究进展作一综述,以期为当下利用ITDD治疗慢性疼痛及后续ITDD的改进提供思路.

Intervertebral disc degeneration (IVDD) presents in a variety of ways and is first manifested by loss of nucleus pulposus (NP) cells, so replenishing NP cells is the key to IVDD treatment. The intensive research into the application of polymer materials and the booming development of decellularization technology offers new hope for patients in relieving pain, replacing damaged nucleus pulposus tissue, reversing degenerative disc cascades, maintaining mechanical properties of the spine and even improving conditions. In this review paper, we first briefly describe the anatomy of intervertebral disc (IVD) and the limitations of traditional therapeutic approaches for IVDD, and then focus on a review of research advances in materials for IVD repair and regeneration including polymeric hydrogels and decellularized nucleus pulposus extracellular matrix (dNP-ECM) technology. Hydrogel material is an ideal polymer material for NP repair, with good mechanical properties. At the same time, dNP-ECM scaffold, as a repair material with low immunogenicity, has attracted increasing attention in the field of IVD regeneration. Although these technologies are not yet widely available for clinical use, these treatment strategies may be a promising alternative approach to IVDD treatment and have great research value.

BackgroundLumbar facet joint cysts (FJCs) are a relatively rare clinical pathology that can result in radiculopathy or neurogenic claudication. Various treatments such as percutaneous aspiration and surgery have been reported to have good clinical outcomes. However, few clinical studies have aimed to treat symptomatic lumbar FJCs by using uniportal full-endoscopic (UFE) surgery. This study aimed to investigate the preliminary clinical outcomes of UFE surgery for the treatment of lumbar FJCs under local anesthesia combined with monitored anesthesia care (MAC).MethodsEight patients (five males and three females) with symptomatic lumbar FJCs who underwent UFE surgery under local and MAC anesthesia were enrolled in this study between January 2018 and April 2022. The clinical characteristics, radiological features, operative information, visual analog scale (VAS) score, Oswestry disability index (ODI), and overall outcome rating based on the modified MacNab criteria were retrospectively analyzed.ResultsOf the eight patients, four underwent a transforaminal approach and four underwent an interlaminar approach. Postoperatively, the mean VAS score for leg pain decreased from 6.1 before surgery to 0.6 after surgery, and the ODI decreased from 74.5% to 14.7%. All patients were followed up for more than 1 year, and the good-to-excellent rate based on the modified MacNab criteria remained 100% at the last follow-up. No complications occurred during the follow-up period.ConclusionLumbar FJCs can cause severe radiating leg pain and/or neurogenic claudication due to the dural sac compression and nerve roots. As an alternative treatment, UFE decompression under local and MAC anesthesia may provide effective clinical outcomes for symptomatic lumbar FJCs.

OBJECTIVE:Full-endoscopic lumbar discectomy (FELD) is a popular operation for the treatment of lumbar disc herniation (LDH) and day surgery mode is increasingly popular. However, only a few studies have reported about day surgery patients undergoing Percutaneous endoscopic lumbar discectomy (PELD). This retrospective study was to evaluate and analyze the clinical outcomes of patients undergoing FELD for LDH as day surgery versus inpatient surgery. METHODS:From January 2020 to January 2022, a retrospective analysis of LDH patients treated with FELD either in day surgery unit (within 8-h hospital stay) or inpatient unit was carried out. All these patients were followed-up for at least 12 months, and were categorized into a FELD-I (inpatient surgery) group or a FELD-D (day surgery) group, according to where the surgical procedures were performed. We assessed and compared the postoperative stand and walk time, postoperative hospitalization stays, time of return to work, modified MacNab criteria, willingness to recommend surgery, complications, revision rate, as well as the visual analogue scale (VAS) and the Oswestry disability index score (ODI). Student t-test was used for continuous variables and chi-square test or Fisher's exact test was used for categorical variables. RESULTS:There was no statistically significant difference in demographic data and baseline characteristics between two groups. And no significant differences were found in MacNab criteria between two groups. Postoperative VAS and ODI scores at one-day postoperation and final follow-up both improved significantly in both groups, as compared to the preoperative data (p < 0.001). However, no significant difference was found between the two groups on the pre, postoperative, or the last follow-up score for VAS and ODI (p > 0.05). The postoperative first ambulation time and postoperative hospital stays was much longer in FELD-I group than FELD-D group (p < 0.001). However, there were no significant differences in the perioperative complications, revision rate as well as satisfaction rate between two groups (p > 0.05). The overall time of return to work of young patients (<60 years-old) in the FELD-D group was significantly shorter than that in the FELD-I group (p = 0.001). Patients in the FELD-D group were more likely to recommend this kind of surgical model. CONCLUSION:These data suggest that FELD-D can be effectively performed as day surgery (within 8 h hospital stay). Early ambulation after FELD-D did not affect the clinical outcomes and the revision rates. Day surgery patients are more likely to recommend this surgery mode to other patients and younger patients may be able to return to work earlier.

Nanofibrous hydrogels are pervasive in load-bearing soft tissues, which are believed to be key to their extraordinary mechanical properties. Enlighted by this phenomenon, a novel reinforcing strategy for polymeric hydrogels is proposed, where polymer segments in the hydrogels are induced to form nanofibers in situ by bolstering their controllable aggregation at the nanoscale level. Poly(vinyl alcohol) hydrogels are chosen to demonstrate the virtue of this strategy. A nonsolvent-quenching step is introduced into the conventional solvent-exchange hydrogel preparation approach, which readily promotes the formation of nanofibrous hydrogels in the following solvent-tempering process. The resultant nanofibrous hydrogels demonstrate significantly improved mechanical properties and swelling resistance, compared to the conventional solvent-exchange hydrogels with identical compositions. This work validates the hypothesis that bundling polymer chains to form nanofibers can lead to nanofibrous hydrogels with remarkably enhanced mechanical performances, which may open a new horizon for single-component hydrogel reinforcement.

OBJECTIVE:To explore the influential factors associated with functional status of those patients who undertook a full-endoscopic lumbar discectomy operation.METHODS:A prospective study was conducted. A total of 96 patients who undertook a full-endoscopic lumbar discectomy operation and met inclusive criteria were enrolled in the study. The postoperative follow-up was held 1 month, 3 months and 6 months after operation. The self-developed record file was used to collect the patient's information and medical history. Visual analogue scale (VAS) score, Oswestry disability index (ODI) score, Gene-ralised anxiety disorder-7 (GAD-7) scale score and patient health questionnaire-9 (PHQ-9) scale score were applied to measure pain intensity, functional status, anxiety status and depression status. Repeated measurement analysis of variance was used to explore the ODI score 1 month, 3 months and 6 months after operation. Multiple linear regression was recruited to illuminate the influential factors associated with functional status after the operation. Logistic regression was employed to explore the independent risk factors related to return to work 6 months after operation.RESULTS:The postoperative functional status of the patients improved gradually. The functional status of the patients 1 month, 3 months and 6 months after operation were highly positively correlated with the current average pain intensity. The factors influencing the postoperative functional status of the patients were different according to the recovery stage. One month and 3 months after operation, the factors influencing the postoperative functional status were the current average pain intensity; 6 months after operation, the factors influencing the postoperative functional status included the current average pain intensity, preoperative average pain intensity, gender and educational level. The risk factors influencing return to work 6 months after operation included women, young age, preoperative depression status and high average pain intensity 3 months after operation.CONCLUSION:It is feasible to treat chronic low back pain with full-endoscopic lumbar discectomy operation. In the process of postoperative functional status recovery, medical staffs should not only take analgesic mea-sures to reduce the pain intensity experienced by the patients, but also pay attention to the impact of psychosocial factors on the recovery. Women, young age, preoperative depression status, and high average pain intensity 3 months after operation may delay return to work after the operation.

目的 分析单通道经皮腰椎脊柱内镜手术治疗腰椎间盘突出症和腰椎管狭窄症术后短期疗效.方法 回顾性分析2020年7月至2021年8月期间在首都医科大学附属北京友谊医院骨科中心接受单通道经皮腰椎脊柱内镜手术共276例患者的资料,其中腰椎间盘突出症患者228例,腰椎管狭窄症患者48例;经椎间孔入路手术患者234例,经椎板间入路手术患者42例.记录手术一般情况,并随访患者的疼痛视觉模拟评分法(VAS)评分,Oswestry腰椎功能障碍指数(ODI)评分,通过改良MacNab评价标准计算术后恢复优良率.结果 276例患者均获随访,随访时间大于6个月.手术时间(60.2±13.2)min,手术出血量(10.5±4.5)mL,住院时间(1.9±1.1)d,未出现神经损伤、血管损伤、感染等严重并发症.手术当天及术后6个月下肢VAS评分为(1.7±0.6)、(1.0±0.7)分,较术前[(4.7±1.5)分]均有显著性降低,差异均有统计学意义(P<0.05).手术当天及术后6个月腰部VAS评分为(1.9±0.7)、(0.9±0.7)分,较术前[(3.8±1.0)分]均有显著性降低,差异均有统计学意义(P<0.05).术后6个月的腰椎ODI评分为(11.1±6.6)％,明显低于术前[(42.2±17.3)％],差异有统计学意义(P<0.05).术后6个月时改良MacNub评分优良率为92.0％,大多数患者均获得满意的疗效.结论 应用单通道经皮腰椎脊柱内镜技术治疗腰椎间盘突出症和腰椎管狭窄症,手术安全、创伤小、住院时间短、恢复快,短期内可以获得满意的临床疗效,值得推广和应用.

Objective:To explore the establishment, optimization and application effect of PELD in the management of lumbar disc herniation under day surgery.Methods:To improve the management process in the day surgery management process according to the management experience of day surgery in our hospital and also the problems of the PELD operation process. We try to formulate the management system and the treatment process of PELD day surgery for lumbar disc herniation and to improve the work norms. Since Jul. 2021, 100 patients in the day surgery were included in this study and followed up more than 30 days. We compared 10 indexes (operation time, wound infection rate, complication rate, stand up rate, day cancellation rate, unpunctuality rate, waiting time before admission, readmission rate within 30 days, delayed discharge rate and patient satisfaction) before and after the application of treatment process. Including.Results:From Mar. to Dec. 2021, a total of 200 PELD surgeries were performed in the day surgery. 100 PELD patients admitted to the day surgery ward from Mar. to Jul. 2021 were the control group. From Jul. to Dec. 2021, another 100 PELD patients were admitted to the day surgery as the observation group. There were no significant differences in age, gender, surgical level, type of protrusion and surgical approach between two groups. After the day surgery management process was established and optimized, the waiting time before admission, complication rate, stand up rate and unpunctuality rate of patients were significantly decreased. The patient satisfaction of observation group was significantly higher than that of control group. However, no significant differences between operation time, wound infection, day cancellation rate, 30-day readmission rate and delayed discharge rate.Conclusions:In the early stage of PELD day surgery, we can establish PELD day surgery procedures suitable for own hospital, referring to the traditional day surgery model. Our diagnosis and treatment process can reduce waiting time before admission, stand up rate and also increase punctuality rate. It can be used by relevant medical units.

OBJECTIVE: To compare and analyze efficacy and safety of percutaneous endoscopic lumbar discectomy (PELD) and open lumbar discectomy (OLD) for adolescent lumbar disc herniation. METHODS: Clinical data of 257 patients with single segment adolescent lumbar disc herniation who underwent surgical treatment from January 2015 to December 2019 were retrospectively collected. The patients were divided into PELD and OLD groups based on the surgical method used. Propensity score matching was performed using preoperative baseline data of patients in both groups, and some patients in both groups were selected for comparative study. Clinical and follow-up data were assessed and compared. RESULTS: There was no statistically significant difference in preoperative baseline data between the 2 groups of patients after propensity score matching. Visual analog scale and Oswestry Disability Index scores improved in both groups postoperatively and at each follow-up time point (P < 0.05). However, visual analog scale scores on the first postoperative day and Oswestry Disability Index scores at 3 months postoperatively were lower in the PELD group than in the OLD group (P < 0.05). Duration of surgery, intraoperative blood loss, and duration of postoperative hospitalization were lower in the PELD group than in the OLD group (P < 0.05). There was no statistically significant & nbsp;difference between the 2 groups when comparing complication and recurrence rates (P >0.05). CONCLUSIONS: Both PELD and OLD are effective and safe surgical techniques for treatment of adolescent lumbar disc herniation. However, compared with OLD, PELD is more advantageous for rapid symptom relief and improving postoperative quality of life with a low rate of complications and recurrence.

Background : Symptomatic lumbar disc herniation is rarely seen among adolescents. Adolescent lumbar disc herniation (ALDH) accounts for 0.5% to 6.8% of all those treated. Evidently, to our knowledge, no studies have emphasized the operative technique to treat two contiguous level adolescent lumbar disc herniation simultaneously. In this study, we aim to investigate the feasibility and advantages of one-stage full-endoscopic lumbar discectomy（FELD）for two contiguous level ALDH. This is the first paper, to my knowledge, dealing with two contiguous level ALDH simultaneously with one-stage full-endoscopic lumbar discectomy. Methods : Between January 2014 and December 2019, patients received FELD surgery for lumbar disc herniation (LDH) in 2 main minimally invasive spine center of China were selected for screening of this study. Data of 5877 cases were retrospectively analyzed (2780 cases and 3097 cases, respectively). The inclusion criteria were patient under 21-year old, two contiguous level symptomatic lumbar disc herniation received one-stage 2 level PELD surgery. Visual analog scale (VAS) scores and modified Macnab criteria were used to assess the preoperative and postoperative clinical results. Results : 11 patients were enrolled in this study (0.19%,11/5877), 8 patients were male and 3 were female. 9 patients with LDH in the same side underwent single-incision 2 level FELD surgery via transforaminal approach. 2 patients with LDH in different side underwent FELD surgery via combined transforaminal and interlaminar approach. There were no immediate perioperative complications. The visual analog scale (VAS) decreased significantly in both early and late follow-up evaluations and these score demonstrated significant improvement in late follow-up (P <0.01). For the modified MacNab criteria, the final outcome results were excellent in 9 patients (81.8%), good in 1 patients (0.9%), fair in1 patients (0.9%), and the overall success rate was 90.9% . Conclusion : One-stage full-endoscopic lumbar discectomy for 2 level symptomatic ALDH is an effective and less invasive method, which can be considered as an alternative good technique for selected adolescent patients.

Study design: A retrospective clinical review.Purpose: To explore the type, morbidity, risk factors and treatment strategies of postoperative complication following percutaneous endoscopic lumbar discectomy (PELD) surgery.Overview of literature: PELD became one of the main operation methods for degenerative lumbar diseases, including disc herniation, stenosis and discogenic low back pain. However, complications following PELD surgery are a considerable challenge for spinal surgeons and seldom addressed publicly.Methods: 10120 patients after PELD surgery were studied. These surgeries were finished by 6 surgeons from 3 main minimal invasive spine centers from January 2012 to June 2017. Most of patients are regularly followed up to explore the type, morbidity, risk factors and treatment strategies of postoperative complication following PELD surgery.Results: There are 2 patients died in the perioperative period and 2 patients with permanent impairment of neural function after surgery, which should be the severest complication of PELD surgery. Transient paresthesia, intraoperative bleeding and dura sac tear are the most common complications reported by 6 surgeons. There are 2 suspected cases of postoperative hematoma, several cases of surgical instruments broken during the surgery and 20 cases of infection in 10120 patients, regarded as rare complications of PELD. Recurrence rate of PELD surgery is 4.7% to 6% reported by 3 surgeons. However, recurrence defined as complications of PELD surgery remain controversial.Conclusion: Excellent clinical outcome of large case series after PELD surgery is reported. However, we need to face the limitations and complications of the surgery. The complication rate should be reduced by caring about the treatment, surgical indications strictly selected and the guidance of experienced surgeons.