Interpretable Machine Learning Model to Predict Bone Cement Leakage in Percutaneous Vertebral Augmentation for Osteoporotic Vertebral Compression Fracture Based on SHapley Additive exPlanations.

STUDY DESIGN: Retrospective study. OBJECTIVES: Our objective is to create comprehensible machine learning (ML) models that can forecast bone cement leakage in percutaneous vertebral augmentation (PVA) for individuals with osteoporotic vertebral compression fracture (OVCF) while also identifying the associated risk factors. METHODS: We incorporated data from patients (n = 425) which underwent PVA. To predict cement leakage, we devised six models based on a variety of parameters. Evaluate and juxtapose the predictive performances relied on measures of discrimination, calibration, and clinical utility. SHapley Additive exPlanations (SHAP) methodology was used to interpret model and evaluate the risk factors associated with cement leakage. RESULTS: The occurrence rate of cement leakage was established at 50.4%. A binary logistic regression analysis identified cortical disruption (OR 6.880, 95% CI 4.209-11.246), the basivertebral foramen sign (OR 2.142, 95% CI 1.303-3.521), the fracture type (OR 1.683, 95% CI 1.083-2.617), and the volume of bone cement (OR 1.198, 95% CI 1.070-1.341) as independent predictors of cement leakage. The XGBoost model outperformed all others in predicting cement leakage in the testing set, with AUC of .8819, accuracy of .8025, recall score of .7872, F1 score of .8315, and a precision score of .881. Several important factors related to cement leakage were drawn based on the analysis of SHAP values and their clinical significance. CONCLUSION: The ML based predictive model demonstrated significant accuracy in forecasting bone cement leakage for patients with OVCF undergoing PVA. When combined with SHAP, ML facilitated a personalized prediction and offered a visual interpretation of feature importance.

Machine Learning Prediction Model and Risk Factor Analysis of Reoperation in Recurrent Lumbar Disc Herniation Patients After Percutaneous Endoscopic Lumbar Discectomy.

OBJECTIVE: To investigate the risk factors of reoperation after percutaneous endoscopic lumbar discectomy (PELD) due to recurrent lumbar disc herniation (rLDH) and to establish a set of individualized prediction models. METHODS: Patients who underwent PELD successfully from January 2016 to February 2022 in a single institution were enrolled in this study. Six methods of machine learning (ML) were used to establish an individualized prediction model for reoperation in rLDH patients after PELD, and these models were compared with logistics regression model to select optimal model. RESULTS: A total of 2603 patients were enrolled in this study. 57 patients had repeated operation due to rLDH and 114 patients were selected from the remaining 2546 nonrecurrent patients as matched controls. Multivariate logistic regression analysis showed that disc herniation type (P < .001), Modic changes (type II) (P = .003), sagittal range of motion (sROM) (P = .022), facet orientation (FO) (P = .028) and fat infiltration (FI) (P = .001) were independent risk factors for reoperation in rLDH patients after PELD. The XGBoost AUC was of 90.71%, accuracy was approximately 88.87%, sensitivity was 70.81%, specificity was 97.19%. The traditional logistic regression AUC was 77.4%, accuracy was about 77.73%, sensitivity was 47.15%, specificity was 92.12%. CONCLUSION: This study showed that disc herniation type (extrusion, sequestration), Modic changes (type II), a large sROM, a large FO and high FI were independent risk factors for reoperation in LDH patients after PELD. The prediction efficiency of XGBoost model was higher than traditional Logistic regression analysis model.

Development of degradable magnesium-based metal implants and their function in promoting bone metabolism (A review).

Background: Use of degradable magnesium (Mg)-based metal implants in orthopaedic surgeries can avoid drawbacks associated with subsequent removal of the non-degradable metallic implants, reducing cost and trauma of patients. Although Mg has been applied in the clinic for orthopaedic treatment, the use of Mg-based metal implants is largely in the research phase. But its application is potentially beneficial in this context as it has been shown that Mg can promote osteogenesis and inhibit osteoclast activity. Methods: A systematic literature search about "degradable magnesium (Mg)-based metal implants" was performed in PubMed and Web of Science. Meanwhile, relevant findings have been reviewed and quoted. Results: In this review, we summarize the latest developments in Mg-based metal implants and their role in bone regeneration. We also review the various molecular mechanisms by which Mg ions regulate bone metabolic processes, including osteogenesis, osteoclast activity, angiogenesis, immunity, and neurology. Finally, we discuss the remaining research challenges and opportunities for Mg-based implants and their applications. Conclusion: Currently, establishment of the in vitro and in vivo biological evaluation systems and phenotypic modification improvement of Mg-based implants are still needed. Clarifying the functions of Mg-based metal implants in promoting bone metabolism is beneficial for their clinical application. The Translational potential of this article: All current reviews on Mg-based implants are mainly concerned with the improvement of Mg alloy properties or the progress of applications. However, there are few reviews that provides a systematic narrative on the effect of Mg on bone metabolism. This review summarized the latest developments in Mg-based metal implants and various molecular mechanisms of Mg ions regulating bone metabolism, which is beneficial to further promote the translation of Mg based implants in the clinic and is able to provide a strong basis for the clinical application of Mg based implants.

Juglone regulates gut microbiota and Th17/Treg balance in DSS-induced ulcerative colitis.

Juglone, mainly isolates from the green walnut husks of Juglans mandshurica, exhibits anti-cancer and anti-inflammaroty activities. But its protection on ulcerative colitis (UC) has never been explored. In this study, we first evaluated whether juglone ameliorated UC, and investigated its effects on gut microbiota and Th17/Treg balance in DSS-induced UC mice model. The model was established by administrating 2.7% DSS for seven days. Juglone was given daily by gavage for ten days, once a day. The disease activity index (DAI) decrease and pathological characteristics improvement demonstrated that the UC in mice was alleviated by juglone. Juglone treatment significantly inhibited the protein levels of IL-6, TNF-α and IL-1ß, improved the protein expression of IL-10. In addition, juglone altered microbial diversity and gut microbiota composition, including the enhancement of the ratio of Firmicutes to Bacteroidota and the abundance of Actinobacteriota, and decrease of the abundance of Verrucomicrobiota. Juglone treatment also inhibited the protein expressions of IL-6, STAT3 and RORγt, meanwhile improved the protein level of FOXP3. Furthermore, juglone inhibited Th17 development and increased Treg generation, beneficial to Th17/Treg balance. Together, we herein provided the first evidence to support that juglone, especially the high dose, possibly protected mice against UC by modulating gut microbiota and restoring Th17/Treg homeostasis.

Comparative analysis of three types of titanium mesh cages for anterior cervical single-level corpectomy and fusion in term of postoperative subsidence.

A titanium mesh cage (TMC) is a common device used for interbody fusion in anterior cervical corpectomy and fusion (ACCF) surgery, with postoperative subsidence being a common complication. Among the many influencing factors, there is a paucity of research on the end-covers of the TMC. A total of 62 patients with cervical spondylotic myelopathy were treated with single-level ACCF. TMC without end-covers (group A), traditional TMC with end-covers (group B) and new TMC with end-covers (group C) were used as the fusion device. We evaluated the surgery time, intraoperative blood loss, postoperative drainage volume, postoperative fusion, falling height of the fused segment, cervical curvature and severe subsidence rate (the number of falling height of the fused segment > 3 mm/total surgical cases in the group). In addition, the Japanese Orthopaedic Association score was used for neurological status assessment and a 10-point Visual Analog Scale for postoperative neck pain. The results showed that the falling height of the fused segment in group A (1.9 ± 0.6 mm) was significantly greater than in group B (0.9 ± 0.2 mm) and group C (0.8 ± 0.3 mm). The area of the end-covers increased gradually in group A, group B and group C, while the severe subsidence rate of group A (8/20, 40%), group B (5/22, 23%) and group C (2/20, 10%) gradually decreased. The surgery time and blood loss in group B (116.4 ± 12.2 min, 183.5 ± 36.4 mL) were higher than those in group A (90.22 ± 5.60 min, 110.4 ± 20.8 mL) and group C (92.8 ± 8.47 min, 114 ± 24.0 mL). These results showed that there was a correlation between the postoperative subsidence and the end-covers of TMC. The larger the end-cover area was, the lower the severe postoperative subsidence rate was. In addition, the design of the end-covers extending inward was more conducive to the operation.

Tailor-made PL-UC-C3 nanoparticles for fluorescence/computed tomography imaging-guided cascade amplified photothermal therapy.

BACKGROUND: Development of the burgeoning number of photothermal therapy (PTT) agents has drawn a huge amount of interest, since PTT treatment is a powerful and effective alternative to traditional treatments. Optimal PTT agents should integrate some essential preconditions including negligible systemic toxicity, deep penetration into tumor tissues, and maximum laser energy absorbance. Unfortunately, only few of the PTT agents reported could meet all of the above mentioned conditions. METHODS: Here, we report a brand new PTT agent through the encapsulation of NaGdF4:Yb,Tm@ NaGdF4:Yb (UCNPs) and an organic compound (C3) into poly-e-caprolactone-polyethylene-polyglycol (PCL-PEG) (PL-UC-C3 NPs). RESULTS: UCNPs as an up-conversion material and C3 as a PTT agent both feature low cytotoxicity, and most importantly, UCNPs with superior conversion efficiency could efficiently absorb the energy of a 980 nm laser, transform the near-infrared laser light into visible light, and translate the palingenetic visible light to C3. The usage of a 980 nm laser ensures a deeper penetration and lower energy, while the highly efficient absorption and transformation process confers a cascade amplified hyperthermia for tumor treatment. CONCLUSION: In this regard, our research provides a powerful and robust breakthrough for florescence/computed tomography imaging-guided PTT treatment, lighting up the clinical application in cancer treatment.

The efficacy and safety of using cooled radiofrequency in treating chronic sacroiliac joint pain: A PRISMA-compliant meta-analysis.

BACKGROUND: Cooled radiofrequency procedure is a novel minimally invasive surgical technique and has been occasionally utilized in managing chronic sacroiliac joint (SIJ) pain. A meta-analysis was conducted to systematically assess the efficacy and safety of using cooled radiofrequency in treating patients with chronic SIJ pain in terms of pain and disability relief, patients' satisfaction degree as well as complications. METHODS: Studies of using cooled radiofrequency procedure in managing SIJ pain were retrieved from Medline and Web of Science according to inclusion and exclusion criteria. Quality evaluation was conducted using Cochrane collaboration tool for randomized controlled trials and MINORS quality assessment for noncomparative trials. Statistics were managed using Review Manager 5.3. RESULTS: Totally 7 studies with 240 eligible patients were enrolled. The overall pooled results demonstrated that pain intensity decreased significantly after cooled radiofrequency procedure compared with that measured before treatment. The mean difference (MD) was 3.81 [95% confidence intervals (95% CIs): 3.29-4.33, P < .001] and 3.78 (95% CIs: 3.31-4.25, P < .001) as measured by the Numerical Rating Scale (NRS) and Visual Analog Scale (VAS), respectively. Disability also relieved significantly after treatment compared with that measured before treatment. The MD was 18.2 (95% CIs: 12.22-24.17, P < .001) as measured by the Oswestry Disability Index (ODI). Seventy-two percent of the patients presented positive results as measured by the Global Perceived Effect (GPE). The OR was 0.01 (95% CIs: 0.00-0.05, P < .001). Only mild complications were observed in the 7 studies, including transient hip pain, soreness, and numbness. CONCLUSION: Cooled radiofrequency procedure can significantly relieve pain and disability with no severe complications, and majority of patients are satisfied with this technique. Thus, it is safe and effective to use this procedure in managing patients with chronic SIJ pain. More high-quality and large-scale randomized controlled trials (RCTs) are required to validate our findings. LIMITATIONS: The sample size of the included studies was small and various heterogeneity existed.

A targeted biocompatible organic nanoprobe for photoacoustic and near-infrared-II fluorescence imaging in living mice.

Multimodal molecular imaging probes have attracted much attention, and they possess great potential to accurately diagnose diseases due to the synergistic superiorities of multiple complementary imaging. Herein, a targeted biocompatible organic nanoplatform (IR-PEG-FA) with a strong optical absorption in the near-infrared window (NIR-I) for photoacoustic imaging (PAI) and excellent second near-infrared (NIR-II) fluorescence imaging property for NIR-II imaging is fabricated. The dual-modal nanoprobe is composed of the small organic dye molecule IR-1061, water-soluble poly(ethylene glycol) (PEG) and folic acid (FA) as the targeted ligands. Depending on the strength of high temporal resolution and preeminent spatial resolution, the targeted biocompatible dual-mode nanoprobe for PAI and NIR-II imaging can provide more detailed date of cancers and diseases, and enables us to specifically diagnose them through quite a precise way.

Outcomes of Microendoscopic Discectomy and Percutaneous Transforaminal Endoscopic Discectomy for the Treatment of Lumbar Disc Herniation: A Comparative Retrospective Study.

STUDY DESIGN: Retrospective, case control evaluation of 86 patients who underwent microendoscopic discectomy (MED) and percutaneous transforaminal endoscopic discectomy (PTED) for the treatment of lumbar disc herniation (LDH). PURPOSE: To evaluate the safety and the outcomes of MED and PTED for the treatment of LDH. OVERVIEW OF LITERATURE: MED and PTED are minimally invasive surgical techniques for lower back pain. Studies to date have shown that MED and PTED are safe and effective treatment modalities for LDH. METHODS: A retrospective study was performed in patients with LDH treated with MED (n=50) and transforaminal endoscopic discectomy (PTED; n=36) in our hospital. All patients were followed-up with self-evaluation questionnaires, Oswestry disability index (ODI), medical outcomes study 36-item short form health survey and MacNab criteria. All the patients in both groups were followed up to 12 months after the operation. RESULTS: ODI questionnaire responses were not statistically different between the MED and PTED groups (53.00 vs. 48.72) before treatment. Average scores and minimal disability after 5 days to 12 months of follow-up were 4.96 in the MED group and 3.61 in the PTED group. According to MacNab criteria, 92.0% of the MED group and 94.4% of the PTED group had excellent or good results with no significant difference. CONCLUSIONS: There was no significant difference between MED and PTED outcomes. Further large-scale, randomized studies with long-term follow-up are needed.

Evaluation of intervertebral disc regeneration with implantation of bone marrow mesenchymal stem cells (BMSCs) using quantitative T2 mapping: a study in rabbits.

PURPOSE: The aim of the study was to investigate the curative effects of transplantation of bone marrow mesenchymal stem cells (BMSCs) on intervertebral disc regeneration and to investigate the feasibility of the quantitative T2 mapping method for evaluating repair of the nucleus pulposus after implantation of BMSCs. METHODS: Forty-eight New Zealand white rabbits were used to establish the lumber disc degenerative model by stabbing the annulus fibrosus and then randomly divided into four groups, i.e. two weeks afterwards, BMSCs or phosphate-buffered saline (PBS) were transplanted into degenerative discs (BMSCs group and PBS group), while the operated rabbits without implantation of BMSCs or PBS served as the sham group and the rabbits without operation were used as the control group. At weeks two, six and ten after operation, the T2 values and disc height indices (DHI) were calculated by magnetic resonance imaging (MRI 3.0 T), and the gene expressions of type II collagen (COL2) and aggrecan (ACAN) in degenerative discs were evaluated by real-time reverse transcription polymerase chain reaction (RT-PCR). T2 values for the nucleus pulposus were correlated with ACAN or COL2 expression by regression analysis. RESULTS: Cell clusters, disorganised fibres, interlamellar glycosaminoglycan (GAG) matrix and vascularisation were observed in lumber degenerative discs. BMSCs could be found to survive in intervertebral discs and differentiate into nucleus pulposus-like cells expressing COL2 and ACAN. The gene expression of COL2 and ACAN increased during ten weeks after transplantation as well as the T2 signal intensity and T2 value. The DHI in the BMSCs group decreased more slowly than that in PBS and sham groups. The T2 value correlated significantly with the gene expression of ACAN and COL2 in the nucleus pulposus. CONCLUSIONS: Transplantation of BMSCs was able to promote the regeneration of degenerative discs. Quantitative and non-invasive T2 mapping could be used to evaluate the regeneration of the nucleus pulposus with good sensitivity.

New cage for posterior minimally invasive lumbar interbody fusion: a study in vitro and in vivo.

OBJECTIVE: To design a new type of interbody fusion device made of nickel titanium NiTi shape memory alloy and to compare segmental stiffness after various posterior lumbar interbody fusion (PLIF) procedures in vitro and in vivo. METHODS: Twelve sheep lumbar functional spinal units were randomly allocated to four groups. One acted as controls (N); the other three were treated with autogenous iliac crest bone dowel graft (L), a threaded cylindrical titanium (KC) interbody fusion device (TFC) or a new type of interbody fusion device made of NiTi shape memory alloy (NT) containing autogenous iliac crest graft. In addition, 15 sheep were allocated to three groups; one served as controls and the other two underwent TFC (KC) or NiTi-FC (NT). Nondestructive mechanical tests were performed in pure compression, extension, lateral bending and torsion. The operated spines were photographed regularly to assess changes in interbody height and degree of fusion. The animals were killed at 6 months for histologic testing. RESULTS: Biomechanical tests showed both the strength and axial stiffness of the NT and KC groups were significantly higher than those of the control group and L group (P < 0.05). When the mechanical performance in torque and torsion of each group were compared, the same results could be obtained. The maximal destructive load of the NiTi-TFC was 11 200 N and the safety coefficient was above 1.2. Radiological observations revealed that the bone callus around the interbody fusion device were gradually increased postoperatively (2 months, no obvious; 4 months, poorly define; 6 months, dense). The KC and NT group had lost 16% and 16.5% of their postoperative height but remained well above normal disc height (P < 0.05). Histologic examination showed new trabeculation connected with that of the host. CONCLUSION: The mechanical characteristics of the NiTi-TFC are excellent and it is safe and reliable.

Ex vivo observation of human nucleus pulposus chondrocytes isolated from degenerated intervertebral discs.

STUDY DESIGN: We performed an ex vivo study to observe cell morphology and viability of human nucleus pulposus (NP) chondrocytes isolated from degenerated intervertebral discs (IVD). PURPOSE: To better understand the biological behavior of NP chondrocytes in monolayer cultures. OVERVIEW OF LITERATURE: Biological repair of IVDs by cell-based therapy has been shown to be feasible in clinical trials. As one of the most promising transplanting seeds, how the isolated NP chondrocytes behavior ex vivo has not been fully understood. METHODS: Human NP chondrocytes were harvested from 20 degenerated IVDs and cultured in monolayers. Histological and immunochemistry staining was used to detect cell morphology change. Cell viability was studied by analyzing cell cycle distribution and apoptotic rate in the primary and subculuted cells. RESULTS: The round or polygonal primary NP chondrocytes had an average adherence time of 7 days and took nearly 31 days to reach 95% confluence. The spindle-shaped P1 NP chondrocytes increased growth kinetics and took about 12 hours to adhere and 6.6 days to get 95% confluent. Immunochemistry staining of collagen II was positive in the cell cytoplasm. Nearly 90% of the confluent NP chondrocytes stayed in G1 phase while 16% underwent apoptosis. No significant difference of the collagen II expression, cell cycle distribution or the apoptosis indices were detected between the primary and subcultured NP chondrocytes. CONCLUSIONS: Human NP chondrocytes undergo significant morphological change in monolayer cultures. Cell cycle distribution pattern and apoptosis index of the cutured NP chondrocytes potentially influence their clinical transplantation or laboratory use.

Long-term outcomes of patients with lumbar disc herniation treated with percutaneous discectomy: comparative study with microendoscopic discectomy.

We assessed the long-term outcomes of patients with lumbar disc herniation treated with percutaneous lumbar discectomy (PLD) or microendoscopic discectomy (MED). A retrospective study was performed in consecutive patients with lumbar disc herniation treated with PLD (n = 129) or MED (n = 101) in a single hospital from January 2000 to March 2002. All patients were followed up with MacNab criteria and self-evaluation questionnaires comprising the Oswestry Disability Index and Medical Outcomes Study 36-Item Short-Form Health Survey. Several statistical methods were used for analyses of the data, and a p value of <0.05 was considered to be statistically significant. A total of 104 patients (80.62%) with PLD and 82 patients (81.19%) with MED were eligible for analyses, with a mean follow-up period of 6.64 +/- 0.67 years and 6.42 +/- 0.51 years, respectively. There were no significant differences between the two groups in age, number of lesions, major symptoms and physical signs, and radiological findings. According to the MacNab criteria, 75.96% in the PLD group and 84.15% in the MED group achieved excellent or good results, respectively, this was statistically significant (p = 0.0402). With the Oswestry Disability Index questionnaires, the average scores and minimal disability, respectively, were 6.97 and 71.15% in the PLD group and 4.89 and 79.27% in the MED group. Total average scores of Medical Outcomes Study 36-Item Short-Form Health Survey were 75.88 vs. 81.86 in PLD group vs. MED group (p = 0.0582). The cost and length of hospitalization were higher or longer in MED group, a statistically significant difference (both p < 0.0001). Long-term complications were observed in two patients (2.44%) in the MED group, no such complications were observed in the PLD group. Both PLD and MED show an acceptable long-term efficacy for treatment of lumbar disc herniation. Compared with MED patients, long-term satisfaction is slightly lower in the PLD patients; complications, hospitalization duration, and costs in PLD group are also lower.

[Long-term outcomes of percutaneous lumbar discectomy and microendoscopic discectomy for lumbar disc herniation].

OBJECTIVE: To evaluate the long-term effects of percutaneous lumbar discectomy (PLD) and microendoscopic discectomy (MED) in treatment of lumbar disc herniation. METHODS: A questionnaire survey by letter and telephone was conducted among 104 patients undergoing PLD and 82 patients undergoing MED during January 2000 to March 2002, to investigate the Oswestry disability index (ODI), Short Form-36 (SF-36) score, and Japanese Orthopedic Association (JOA) score. RESULTS: The excellent/good rate (ODI score=0-20%) of the MED group was 79.27%, significantly higher than that of the PLD group (71.15%, P=0.0397). However, longer The hospitalization duration of the MED group was 11, 6 d, significantly longer than that of the PLD group (7.9 d, P<0.01), and the mean cost of the MED group was, significantly higher than that of the PLD group (P<0.01). Long-term complications were observed in 3 patients of the MED group (3.49%) while none in the PLD group. CONCLUSION: Both PLD and MED are minimally-invasive-technique with a long-term efficacy and safety on lumbar disc herniation. Although the long-term outcome of the MED group is better than PLD, the complication rate, hospitalization duration, and cost of the MED group are higher.

Microendoscopic discectomy for lumbar disc herniation: surgical technique and outcome in 873 consecutive cases.

STUDY DESIGN: A retrospective review involving 873 consecutive cases of lumbar disc herniation treated by microendoscopic discectomy (MED) was conducted and a mean 28-month follow-up was performed. OBJECTIVE: The purpose of this study was to describe the MED technique for lumbar disc herniation and report long-time outcome and complications. SUMMARY OF BACKGROUND DATA: The conception of MED was introduced in 1997. Long-time outcome has not been described. METHOD: A total of 873 consecutive patients with lumbar disc herniation were treated with the METRx system. Oswestry Disability Index (ODI) was used to quantify pain relief. The degree of pain and disability was also measured by visual analog scale (VAS) and modified MacNab criteria. A control group of 358 patients treated with standard open discectomy was used for comparison. RESULTS: There was significant improvement in the mean preoperative and postoperative VAS and ODI score for the MED and open groups, and there was no statistical difference of the pain improvement between the two groups. For the MED group, average length of hospital stay was 4.8 days; mean time to return to work or normal activities was 15 days; average operative blood loss per level was 44 mL. These were significantly less than open group. CONCLUSIONS: MED is an effective microendoscopic system with fine long-term outcome in treating lumbar disc herniation. The endoscopic approach allows smaller incisions and less tissue trauma, compared with standard open microdiscectomy. Strict adherence to well-defined preoperative selection criteria could ensure optimal postoperative outcome.