A Deep-Learning Model for Predicting the Efficacy of Non-vascularized Fibular Grafting Using Digital Radiography.

RATIONALE AND OBJECTIVES: To develop a fully automated deep-learning (DL) model using digital radiography (DR) with relatively high accuracy for predicting the efficacy of non-vascularized fibular grafting (NVFG) and identifying suitable patients for this procedure. MATERIALS AND METHODS: A retrospective analysis was conducted on osteonecrosis of femoral head patients who underwent NVFG between June 2009 and June 2021. All patients underwent standard preoperative anteroposterior (AP) and frog-lateral (FL) DR. Subsequently, the radiographs were pre-processed and labeled based on the follow-up results. The dataset was randomly divided into training and testing datasets. The DL-based prediction model was developed in the training dataset and its diagnostic performance was evaluated using the testing dataset. RESULTS: A total of 339 patients with 432 hips were included in this study, with a hip preservation success rate of 71.52% as of June 2023. The hips were randomly divided into a training dataset (n = 324) and a testing dataset (n = 108). The ensemble model in predicting the efficacy of NVFG, reaching an accuracy of 78.9%, a precision of 78.7%, a recall of 96.0%, a F1-score of 86.5%, and an area under the curve (AUC) of 0.780. FL views (AUC, 0.71) exhibited better performance compared to AP views (AUC, 0.66). CONCLUSION: The proposed DL model using DR enables automatic and efficient prediction of NVFG efficacy without additional clinical and financial burden. It can be seamlessly integrated into various clinical scenarios, serving as a practical tool to identify suitable patients for NVFG.

Predicting efficacy and guiding procedure choice in non-vascularized bone grafting: a CT Radiomics and clinical predictor approach.

OBJECTIVES: There is no practical approach for accurately predicting the efficacy of non-vascularized bone grafting (NVBG) and guiding its optimal procedure. MATERIALS AND METHODS: This study enrolled 153 patients with 182 hips that underwent NVBG procedures. The patients were randomly divided into a training cohort (n = 130) and a validation cohort (n = 52). In the training cohort, radiomics model, clinical model, and combined radiomics-clinical (C-R) model were constructed using Rad-scores and clinical predictors to predict the efficacy of NVBG. The optimal model was visualized by a nomogram and assessed by decision curve analysis (DCA). 128 hips that underwent successful NVBG were then randomized into a new training cohort (n = 92) and a new validation cohort (n = 36), and three models were constructed and validated to predict the choice of NVBG procedure. RESULTS: Japanese Investigation Committee (JIC) classification, exposure to risk factors postoperative, and Rad-scores consisting of four radiomics features were independent predictors for the efficacy of NVBG (P < 0.05). The C-R model provided better performance in both the training cohort (AUC: 0.818) and validation cohort (AUC: 0.747). To predict the choice of NVBG procedure, the C-R model built by JIC classification and Rad-scores consisting of five radiomics features showed the finest performance in both cohorts (AUC: 0.860 and 0.800, respectively). DCA showed great benefit using the C-R model for the choice of NVBG procedure. CONCLUSION: The approach integrated by CT radiomics and clinical predictors can be visually and quantitatively applied to predict the efficacy and guide the choice of NVBG procedure with great predictive accuracy.

[Visual and quantitative assessment of the effectiveness of non-vascularized bone grafting in osteonecrosis of the femoral head via CT-based radiomics and clinical data].

Objective: To investigate the value of CT-based radiomics and clinical data in predicting the efficacy of non-vascularized bone grafting (NVBG) in hip preservation, and to construct a visual, quantifiable, and effective method for decision-making of hip preservation. Methods: Between June 2009 and June 2019, 153 patients (182 hips) with osteonecrosis of the femoral head (ONFH) who underwent NVBG for hip preservation were included, and the training and testing sets were divided in a 7∶3 ratio to define hip preservation success or failure according to the 3-year postoperative follow-up. The radiomic features of the region of interest in the CT images were extracted, and the radiomics-scores were calculated by the linear weighting and coefficients of the radiomic features after dimensionality reduction. The clinical predictors were screened using univariate and multivariate Cox regression analysis. The radiomics model, clinical model, and clinical-radiomics (C-R) model were constructed respectively. Their predictive performance for the efficacy of hip preservation was compared in the training and testing sets, with evaluation indexes including area under the curve, C-Index, sensitivity, specificity, and calibration curve, etc. The best model was visualised using nomogram, and its clinical utility was assessed by decision curves. Results: At the 3-year postoperative follow-up, the cumulative survival rate of hip preservation was 70.33%. Continued exposure to risk factors postoperative and Japanese Investigation Committee (JIC) staging were clinical predictors of the efficacy of hip preservation, and 13 radiomic features derived from least absolute shrinkage and selection operator downscaling were used to calculate Rad-scores. The C-R model outperformed both the clinical and radiomics models in predicting the efficacy of hip preservation 1, 2, 3 years postoperative in both the training and testing sets ( P<0.05), with good agreement between the predicted and observed values. A nomogram constructed based on the C-R model showed that patients with lower Rad-scores, no further postoperative exposure to risk factors, and B or C1 types of JIC staging had a higher probability of femoral survival at 1, 2, 3 years postoperatively. The decision curve analysis showed that the C-R model had a higher total net benefit than both the clinical and radiomics models with a single predictor, and it could bring more net benefit to patients within a larger probability threshold. Conclusion: The prediction model and nomogram constructed by CT-based radiomics combined with clinical data is a visual, quantifiable, and effective method for decision-making of hip preservation, which can predict the efficacy of NVBG before surgery and has a high value of clinical application.

Prognosis and risk prediction of bone impaction grafting through femoral head-neck fenestration: a retrospective cohort study.

The bone impaction grafting through femoral head-neck fenestration was a favorable hip preservation procedure but without prognosis estimation. This study retrospectively reviewed 79 patients' clinical data (114 hips) with osteonecrosis of the femoral head (ONFH) who underwent this procedure from June 2009 to June 2019. By the end of June 2022, the median survival time of the hip was (74.13 ± 44.88) months, and the success rate of hip preservation was 68.42%. Lateral reserved angle (LPA) and combined reserved angle (CPA) had statistically significant differences (P < 0.001) both in univariate analysis and a multivariate logistic regression model. The multivariate logistic regression model of area under curve (AUC) area of the receiver operating characteristic (ROC) curve was 0.931(sensitivity = 95.00%, specificity = 88.40%, log-rank test: P < 0.01), and the calibration curve indicated good prediction accuracy. The ROC analysis and Cox proportional hazards regression model revealed that the cutoff point of LPA was 50.95° (sensitivity = 95.00%, specificity = 72.09%, log-rank test: P < 0.05) and the cutoff point of CPA was 90.51° (sensitivity = 90.00%, specificity = 90.70%, log-rank test: P < 0.05). A nomogram plot to predict the risk of failure (C-index = 0.873, 95% CI: 0.785 to 0.961) and nomograms for predicting the survival probability at 1, 2 or 3 years whose calibration curves showed excellent prediction accuracy were available for the clinician. Preserved angles (PAs) are valuable in the prediction of prognosis in surgical treatment. The bone impaction grafting through femoral head-neck fenestration can achieve better clinical efficacy, especially for patients with LPA >50.95° and CPA >90.51°.

Mid- to long-term results of modified avascular fibular grafting for ONFH.

Free vascularized fibular grafting was reported a favorable method to prevent the collapse of the femoral head. This study analyzed the mid- to long-term outcomes of avascular fibular grafting (AVFG) for osteonecrosis of the femoral head (ONFH) with 6- to 8-year follow-up. From March 2009 to March 2012, 34 patients (48 hips) were diagnosed with ONFH operated with AVFG in Jiangsu Province Hospital of traditional Chinese Medicine. We retrospectively reviewed the clinic outcomes of these patients and evaluated the differences in outcomes by diverse stages [Association Research Circulation Osseous (ARCO)] and types [China-Japan Friendship Hospital (CJFH) classification] annually. The hip survival rate, Harris hip score (HHS), activity level and imaging stability were calculated. The average follow-up time was 6.7 years. At the last follow-up, 34 of 48 hips survived totally. According to the ARCO stage, the overall clinical success rate for hip preserving were 76.0% (19/25) in II stage, 85.7% (12/14) in IIIA stage and 33.3% (3/9) in IIIB stage. Referring to the CJFH classification system, the hip survival rate were 100% (2/2) in M type, 90.9% (10/11) in C type, 77.8% (14/18) in L1 type, 57.1% (8/14) in L2 type and 0% (0/3) in L3 type. The mean visual analog scale (VAS) score, HHS and Western Ontario McMaster Osteoarthritis index (WOMAC) were significantly improved at the final follow-up compared with pre-operative values (P < 0.001). The AVFG operation can increase the hip function and improve patients' lives quality. The mid- to long-term efficacy can satisfy fundamental life requirements, especially for those early-stage and small-scale patients who suffer ONFH to avoid or put off the time of total hip arthroplasty surgery.

Clinical reports of surgical dislocation of the hip with sequestrum clearance and impacting bone graft for grade IIIA-IIIB aseptic necrosis of femoral head (ANFH) patients.

OBJECTIVE: To analyze the treatment effect of surgical dislocation of the hip with sequestrum clearance and impacting bone graft in grade IIIA-IIIB aseptic necrosis of femoral head (ANFH) patients. METHODS: From June 2012 to December 2014, 6 patients (total 8 hips) with grade IIIA-IIIB ANFH were retrospectively followed. All the patients were operated with surgical dislocation of the hip with sequestrum clearance and impacting bone graft. Collapse of the femoral head, healing of the osteotomy, along with Harris hip scores were observed after surgeries. RESULTS: All the patients were followed up, the osteotomies were all healed. Only 1 of the 8 hips (12.5%) was collapsed by the last follow-up. Harris hip scores were improved from 54.52 ± 8.16 to 80.53 ± 7.62 (P <0.001). The excellent rate was 87.5%. CONCLUSION: For grade IIIA-IIIB ANFH patients, surgical dislocation with sequestrum clearance and impacting bone graft could possibly achieve satisfactory clinical benefit, particularly for the young patients.

Abnormal Skeletal Growth in Adolescent Idiopathic Scoliosis Is Associated with Abnormal Quantitative Expression of Melatonin Receptor, MT2.

The defect of the melatonin signaling pathway has been proposed to be one of the key etiopathogenic factors in adolescent idiopathic scoliosis (AIS). A previous report showed that melatonin receptor, MT2, was undetectable in some AIS girls. The present study aimed to investigate whether the abnormal MT2 expression in AIS is quantitative or qualitative. Cultured osteoblasts were obtained from 41 AIS girls and nine normal controls. Semi-quantification of protein expression by Western blot and mRNA expression by TaqMan real-time PCR for both MT1 and MT2 were performed. Anthropometric parameters were also compared and correlated with the protein expression and mRNA expression of the receptors. The results showed significantly lower protein and mRNA expression of MT2 in AIS girls compared with that in normal controls (p = 0.02 and p = 0.019, respectively). No differences were found in the expression of MT1. When dichotomizing the AIS girls according to their MT2 expression, the group with low expression was found to have a significantly longer arm span (p = 0.036). The results of this study showed for the first time a quantitative change of MT2 in AIS that was also correlated with abnormal arm span as part of abnormal systemic skeletal growth.

Abnormal leptin bioavailability in adolescent idiopathic scoliosis: an important new finding.

STUDY DESIGN: This was a cross-sectional study. OBJECTIVE: The present study aimed to explore the differences in leptin bioavailability between adolescent idiopathic scoliosis (AIS) and healthy age-matched girls in a Chinese Han population. SUMMARY OF BACKGROUND DATA: AIS is a common spinal deformity mainly occurring in girls during the peripubertal period. The development of scoliosis is related to relative anterior spinal overgrowth. AIS girls also have associated lower body mass index (BMI) and lower bone mineral status. Leptin, together with soluble leptin receptor (sOB-R), was shown to play an important role in the regulation of bone and energy metabolism in children. It was hypothesized that leptin and sOB-R are abnormal and associated with deranged growth and anthropometric phenotypes in AIS girls. METHODS: Serum leptin and sOB-R were measured together with documentation of anthropometric parameters and clinical data in 95 AIS girls and 46 healthy matched controls (age 11-16 years). Serum leptin and sOB-R concentrations were measured by enzyme-linked immunosorbent assay and correlated with the different measured parameters. RESULTS: AIS girls had significantly lower BMI and longer arm span than healthy controls. AIS girls were found to have significantly higher sOB-R levels and lower free leptin index (FLI) after adjusting for age and body weight in multivariate regression analysis. Significant correlation was found between sOB-R, FLI, and curve severity in AIS girls. CONCLUSION: This is the first study demonstrating the presence of abnormal leptin bioavailability in AIS girls that might play an important role in the etiopathogenesis of AIS. Further investigation is required to provide a better understanding of the underlying mechanisms, with the aim to explore the potential clinical application as a biomarker for predicting curve initiation or progression in AIS.

Abnormal melatonin receptor 1B expression in osteoblasts from girls with adolescent idiopathic scoliosis.

Melatonin signaling dysfunction has been associated with the etiology of adolescent idiopathic scoliosis (AIS). Genetic analysis has also associated the occurrence of AIS with the MT2 gene. Thus, we determined whether there is abnormality in the protein expression of melatonin receptors (MT) in AIS osteoblasts. In this study, we recruited 11 girls with severe AIS and eight normal subjects for intraoperative bone biopsies. MT1 and MT2 receptor protein expressions in the isolated osteoblasts were detected. Also, cell proliferation assay using different melatonin concentrations (0, 10(-9), 10(-5), 10(-4) m) was carried out. The results showed that both MT1 and MT2 receptors are expressed in osteoblasts of the controls. While MT1 receptors were expressed in osteoblasts of all AIS subjects, osteoblasts of only 7 of 11 AIS showed expression of MT2 receptors. Melatonin stimulated control osteoblasts to proliferate. However, proliferation of AIS osteoblasts without expression of MT2 receptor, after treatment with melatonin, was minimal when compared with control and AIS osteoblasts with MT2 receptor expression. The proliferation of AIS osteoblasts with MT2 receptor was greater than those without. This is the first report demonstrating a difference between AIS and normal osteoblasts in the protein expression of MT2 receptor. The results suggest that there is a possible functional effect of MT2 receptor on osteoblast proliferation. AIS osteoblasts without expression of MT2 receptor showed the lowest percentage of viable cells after melatonin treatment. This possibly indicates the modulating role of melatonin through MT2 receptor on the proliferation of osteoblasts.

Rib length asymmetry in thoracic adolescent idiopathic scoliosis: is it primary or secondary?

The development of scoliosis in animal models after inducing asymmetric rib growth suggests the possible role of asymmetric rib growth in the etiopathogenesis of adolescent idiopathic scoliosis (AIS). Asymmetric rib length is well recognized in idiopathic scoliosis; however, whether this rib asymmetry is primary or secondary has not been clearly documented. The objectives of this study were to investigate any rib length asymmetry in patients with AIS and compare those with scoliosis with syringomyelia (SS) with the intention of elucidating any relationship between rib growth and pathogenesis of AIS. Forty-eight AIS and 29 SS with apical vertebrae located between T7 and T9 were recruited. The average age was 13.5 ± 2.3 versus 12.5 ± 3.4 years, and the average Cobb angle of thoracic curve was 43.3° ± 16.4° versus 45.6° ± 22.6° in patients with AIS or SS, respectively. The length of all ribs was measured from the tip of costal head to the end of the same rib by built-in software on spiral computed tomography. At the levels of the apical vertebrae, the vertebrae above and below the apex, the mean discrepancy in rib length (concave minus convex rib) was 7, 4 and 7 mm, respectively, in AIS group (p < 0.01), and 6, 5 and 7 mm in SS group, respectively (p < 0.01). The rib length discrepancy between concave and convex sides was significantly correlated with the magnitude of the Cobb angle of thoracic curve in both AIS and SS groups (p < 0.01). Similar findings of the asymmetry of rib length in both AIS and SS patients pointed strongly to the fact that the rib length asymmetry in apical region is most likely secondary to the scoliosis deformity rather than playing a primary role in the etiopathogenesis.

Rib length discrepancy in patients with adolescent idiopathic scoliosis.

The development of scoliosis in animal models with induced asymmetric rib growth suggested the possible role of asymmetric rib growth in the etiopathogenesis of adolescent idiopathic scoliosis (AIS). Asymmetric rib length is well recognized in idiopathic scoliosis, however, whether this rib asymmetry was primary or secondary has not been clearly documented. We measured the lengths of all ribs in 48 patients with AIS and 29 patients with scoliosis associated with syringomyelia and Chiari I malformation (SS). In both groups, ribs on the concave side were significantly longer than those on the convex side in apical area. The rib length difference was significantly associated with magnitude of the Cobb angle of thoracic curve. However, the rib length discrepancy showed no difference between AIS and SS group. The finding of similar asymmetry of rib length in both AIS and SS patients with thoracic curve indicated the discrepancy found in AIS might be secondary to the spinal deformity rather than its etiological factor.

[Classification of thoracic pedicle according to the transverse diameters in thoracic idiopathic scoliosis patients and its clinical significance].

OBJECTIVES: To explore the clinical significance of the transverse thoracic pedicle diameters measurement and thoracic pedicles classification in thoracic adolescent idiopathic scoliosis patients. METHODS: Thirty thoracic idiopathic scoliosis patients who were hospitalized during October 2008 and July 2009 and 20 non-scoliosis adolescents who were adopted during August 2008 and July 2009 were included in this study. Successive CT thoracic vertebrae scanning of all subjects were obtained. All participants' transverse pedicle diameters of the thoracic vertebrae were measured with the software of PACS Client. Classified the pedicle into 4 types according to the transverse pedicle diameters. In control group, the transverse pedicle diameters of bilateral thoracic vertebrae were compared using paired-t test. In AIS group, the transverse pedicle diameters of concave and convex side thoracic vertebrae were compared using paired-t test. The distribution of pedicle types were compared using Chi-Square test between the control group and AIS group. RESULTS: The transverse pedicle diameters showed a decreasing trend from T(1) to T(4) followed by an increasing trend from T(5) to T(12) in both groups. The bilateral transverse pedicle diameters had no significant difference in the control group. The transverse pedicle diameters of the concave side at the apex of thoracic curve were found to be significantly thinner than those of convex side. The ratio of Type 4 was higher in thoracic adolescent idiopathic scoliosis patients than the controls, and the ratio of Type 1 was smaller in thoracic adolescent idiopathic scoliosis patients than the controls. CONCLUSIONS: The thoracic pedicles in thoracic adolescent idiopathic scoliosis patients are often rather thinner. Preoperative CT measurement of thoracic pedicle in the treatment of idiopathic scoliosis is suggested helpful in deciding the correct strategy of pedicle screw insertion and decreasing the risk of clinically relevant neurovascular complications.

[A preliminary study of melatonin signaling transduction pathway in BMSCs from adolescent idiopathic scoliosis patients].

OBJECTIVE: To investigate the melatonin signaling transduction pathway in BMSCs from adolescent idiopathic scoliosis patients. METHODS: Twenty-four volunteers aged 12 - 18 years were divided into two groups: AIS group was 15 and control group was 9. The human bone marrow anticoagulated by heparin was obtained from anterior superior iliac spine, and the BMSCs were isolated by density gradient centrifuge from the mononuclear cells, and then were cultivated and serial subcultivated in vitro. P3 cultures were analyzed by the flow cytometry to determine the surface antigens. P3 BMSCs were used to detect the melatonin signaling transduction pathway. The cellular cAMP was elevated using forskolin, and then the BMSCs were treated with melatonin to inhibit the cellular cAMP levels. RESULTS: Mononuclear cells were cultivated and subcultivated to P3 culture in vitro, which were analyzed by the flow cytometry, and demonstrated that the expanded mononuclear cells expressed mesenchymal cell markers. The basal cAMP levels of the two groups were very low, after the stimulation of forskolin, cellular cAMP levels increased rapidly in all the patients, but after the stimulation of melatonin at physiological dose or even at pharmacological dose, there was no statistical difference of the inhibition of cAMP between AIS group and control (P > 0.05). CONCLUSION: Melatonin signaling transduction pathway may be normal in BMSCs from AIS patients.