Effects of demineralization mode and particle size of allogeneic bone powder on its physical and chemical properties.

At present, the commonly used allogeneic bone powder in the clinic can be divided into nondemineralized bone matrix and demineralized bone matrix (DBM). Commonly used demineralizers include acids and ethylene diamine tetraacetic acid (EDTA). There may be some diversities between them. Also, the size of the bone particle can affects its cell compatibility and osteogenic ability. We produced different particle sizes i.e., < 75, 75-100, 100-315, 315-450, 450-650, and 650-1000 µm, and treated in three ways (nondemineralized, demineralized by EDTA, and demineralized by HCl). Scanning electron microscopy showed that the surface of the samples in each group was relatively smooth without obvious differences. The results of specific surface area and porosity analysis showed that they were significantly higher in demineralized bone powder than in nondemineralized bone powder, however, there was no significant difference between the two decalcification methods. The content of hydroxyproline in nondemineralized bone powder and EDTA-demineralized bone powder had no statistical difference, while HCl-demineralization had statistical significance compared with the former two, and the content increased with the decrease of particle size. The protein and BMP-2 extracted from HCl demineralized bone powder were significantly higher than that from nondemineralized bone powder and EDTA demineralized bone powder, and there were differences among different particle sizes. These results suggested the importance of demineralization mode and particle size of the allogenic bone powder and provided guidance for the choice of the most appropriate particle size and demineralization mode to be used in tissue bioengineering.

Repair of tendons treated with peracetic acid-ethanol and gamma irradiation by EDC combined with NHS: a morphological, biochemical and biomechanical study in vitro.

The purpose of this study was to investigate whether 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) combined with n-hydroxysuccinimide (NHS) can repair tendon damage caused by peracetic acid-ethanol and gamma irradiation sterilization. The semitendinosus tendons of 15 New Zealand white rabbits were selected as experimental materials, and the tendons were sterilized in a solution containing 1% (v/w) peracetic acid and 24% (v/w) ethanol. After 15 kGy gamma irradiation sterilization, the tendons were randomly divided into three groups (n = 10). The tendons were repaired with EDCs of 0, 2.5 and 5 mM combined with 5 mM NHS for 6 h, the tendons were temporarily stored at - 80 ± °C. The arrangement and spatial structure of collagen fibers were observed by light microscopy and scanning electron microscopy, the collagen type and collagen crimp period were observed under a polarizing microscope, and the collagen fibril diameter and its distribution were measured by transmission electron microscopy, from which the collagen fibril index and mass average diameter were calculated. The resistance of collagen to enzymolysis was detected by the free hydroxyproline test, and tensile fracture and cyclic loading tests of each group of tendons were carried out, from which the elastic modulus, maximum stress, maximum strain, strain energy density and cyclic creep strain were calculated. The obtained results showed that the gap between loose collagen fibers in the 0 mM control group was wider, the parallel arrangement of tendons in the 2.5 and 5 mM groups was more uniform and regular and the fiber space decreased, the crimp period in the 5 mM group was lower than that in the 0 mM group (P < 0.05), and the concentration of hydroxyproline in the 5 mM group (711.64 ± 77.95 µg/g) was better than that in the control group (1150.57 ± 158.75 µg/g). The elastic modulus of the 5 mM group (424.73 ± 150.96 MPa) was better than that of the 0 mM group (179.09 ± 37.14 MPa). Our results show that EDC combined with NHS can repair damaged tendons after peracetic acid-ethanol and gamma radiation treatment, and 5 mM EDC has better morphological performance, anti-enzymolysis ability and biomechanical properties than 2.5 mM EDC.

Comparison of demineralized bone matrix with different cycling crushing times in posterolateral fusion model of athymic rats.

Decalcified bone matrix (DBM) is a widely used alternative material for bone transplantation. In the DBM production process, an effective particle size and the highest utilization rate of raw materials can be achieved only through multiple high-speed circulating comminution. The rat posterolateral lumbar fusion model (PLF) is the most mature small animal model for the initial evaluation of the efficacy of graft materials for bone regeneration and spinal fusion. To evaluate the differences in the in vivo osteogenic effects of DBM pulverization through 1, 5, 9, and 14 high-speed cycles, sixty athymic rats were divided into six groups: single cycling crushing (CC1), 5 cycles of crushing (CC5), 9 cycles of crushing (CC9), 13 cycles of crushing (CC13), autogenous bone graft (ABG) and negative control (NC). Posterolateral lumbar fusion was performed. Six weeks after surgery, the bilateral lumbar fusion of athymic rats was evaluated through manual palpation, X-ray, micro-CT and histological sections. Rank data were tested by the rank-sum test, and nonparametric data were tested by the Kruskal‒Wallis H test. The manual palpation and X-ray results showed that the fusion rate did not significantly differ between the CC1, CC5, CC9, CC13 and ABG groups. However, cavities appeared in CC9 and CC13 on the micro-CT image. The bone mass (BV/TV) of CC1, CC5, CC9 and CC13 was better than that of the ABG group, while almost no osteogenesis was observed in the NC group. Histologically, there was no obvious difference between the four groups except that the CC9 group and CC13 group had more fibrous tissues in the new bone. In conclusion, DMB with different cycling crushing times has no obvious difference in fusion rate of PLF, but it is slightly better than the ABG group.

A novel tool for predicting the survival of endoprosthesis used for reconstruction of the knee following tumor resection: a retrospective cohort study.

BACKGROUND: Prosthesis-related complications, after knee reconstruction with endoprosthesis during operation for tumors around the knee, remain an unresolved problem which necessitate a revision or even an amputational surgery. The purpose of the current study was to identify significant risk factors associated with implant failure, and establish a novel model to predict survival of the prosthesis in patients operated with endoprostheses for tumor around knee. METHODS: We retrospectively reviewed the clinical database of our institution for patients who underwent knee reconstruction due to tumors. A total of 203 patients were included, including 123 males (60.6%) and 80 (39.4%) females, ranging in age from 14 to 77 years (mean: 34.3 ± 17.3 years). The cohort was randomly divided into training (n = 156) and validation (n = 47) samples. Univariable COX analysis was used for initially identifying potential independent predictors of prosthesis survival with the training group (p < 0.150). Multivariate COX proportional hazard model was selected to identify final significant prognostic factors. Using these significant predictors, a graphic nomogram, and an online dynamic nomogram were generated for predicting the prosthetic survival. C-index and calibration curve were used for evaluate the discrimination ability and accuracy of the novel model, both in the training and validation groups. RESULTS: The 1-, 5-, and 10-year prosthetic survival rates were 94.0, 90.8, and 83.0% in training sample, and 96.7, 85.8, and 76.9% in validation sample, respectively. Anatomic sites, length of resection and length of prosthetic stem were independently associated with the prosthetic failure according to multivariate COX regression model (p<0.05). Using these three significant predictors, a graphical nomogram and an online dynamic nomogram model were generated. The C-indexes in training and validation groups were 0.717 and 0.726 respectively, demonstrating favourable discrimination ability of the novel model. And the calibration curve at each time point showed favorable consistency between the predicted and actual survival rates in training and validation samples. CONCLUSIONS: The length of resection, anatomical location of tumor, and length of prosthetic stem were significantly associated with prosthetic survival in patients operated for tumor around knee. A user-friendly novel online model model, with favorable discrimination ability and accuracy, was generated to help surgeons predict the survival of the prosthesis.

Comparative assessment of biomechanics induced by hinge knee prostheses with two different motion axial system.

We aimed to evaluate the biomechanical contact characteristics of rotating hinge knee (RHK) prostheses with different motion axial systems. We performed finite element (FE) analyses to investigate and compare the peak contact stress and contact location on tibial insert and bushing during a gait cycle. The biaxial (BA) system and spherical center axial (SA) system RHK prostheses were included in this study. The comparisons between experimental tests and FE analyses were performed to verify the validation of FE models. Decreased ISO loadings were then applied to the validated FE models to investigate the peak contact stress and contact location on tibial insert and bushing. The contact areas obtained from experimental tests and FE analyses were in a good agreement. The peak contact stresses on tibial insert and bushing of BA prosthesis were higher than those of SA prosthesis. The contact locations on the superior surface of tibial insert in SA and BA prostheses were at the middle-posterior and posterior side, while those on the rotating axial surface were at the medial and lateral sides, respectively. This study indicate that the tibial insert and bushing of an SA prosthesis have lower peak contact stresses and better contact locations than those of a BA prosthesis during a gait cycle, which may decrease the risk of long-term complications of RHK prostheses. Future studies should be performed to confirm the relationship between the contact characteristics and wear in RHK prostheses.

Efficacy and safety of bone substitutes in lumbar spinal fusion: a systematic review and network meta-analysis of randomized controlled trials.

PURPOSE: A variety of alternative grafts to autologous iliac crest bone (ICBG) have been developed for lumbar spondylodesis, due to frequent complications following ICBG harvest. The optimal alternative graft to ICBG, however, remains elusive till now. The purpose of this study was to compare the efficacy and safety of fusion materials in lumbar degeneration diseases and to provide a ranking spectrum of the grafts. METHODS: Randomized controlled trials (RCTs) comparing different bone grafts in lumbar arthrodesis were eligible for inclusion. A network meta-analysis was performed for endpoints including fusion rate and incidence of adverse events. RESULTS: Twenty-seven RCTs involving 2488 patients and 13 available interventions were included. rhBMP-2 provided the highest fusion rate, being significantly superior to that of ICBG (OR = 0.21, p < 0.001), autograft local bone (ALB) (OR = 0.18, p = 0.022), rhBMP-7 (OR = 0.15, p < 0.001), allograft (OR = 0.13, p = 0.009), and DBM + ALB (OR = 0.07, p = 0.048). The treatment efficacy of allograft could be significantly enhanced by bone marrow concentrate (BMC) supplying (OR = 0.16, p = 0.010). ICBG ranks second on the frequency of complications, which is significantly higher than that of allograft (OR = 0.14, p = 0.041) and ALB (OR = 0.14, p = 0.030). All of the other comparisons showed similar efficacy and safety profiles between groups. CONCLUSION: Ranking spectrums of the efficacy and safety for various bone grafts were provided graphically. Though rhBMP-2 was of the highest success rate, the application should be taken with proper caution because of the widely proposed life-threatening adverse events. ALB, ALB plus synthetic ceramic materials and allograft mixed with BMC were also proved to be potentially effective alternative graft to ICBG. These slides can be retrieved under Electronic Supplementary Material.

Predictive Value of the Nomogram Model in Patients With Megaprosthetic Failure Around the Knee: A Retrospective Analysis.

BACKGROUND: Megaprosthetic replacement is one of the main methods for reconstructing mega bone defects after tumor resection. However, the incidences of complication associated with tumor prostheses were 5-10 times higher than that of conventional total knee arthroplasty. The objective of this study is to establish and validate a nomogram model which can assist doctors and patients in predicting the prosthetic survival rates. METHODS: Data on cancer patients treated with tumor prosthesis replacements at our institution from November 2001 to November 2017 were collected. The potential risk factors which were well-studied and shown to be associated with megaprosthetic failure were analyzed. A nomogram model was established using independent risk factors screened out by multivariate regression analysis. The concordance index and calibration curve were selected for internal validation of the predictive accuracy of nomogram. RESULTS: The 3-, 5-, 10-, and 15-year prosthetic survival rates were 92.8%, 88.6%, 74.1%, and 48.3%, respectively. The prosthetic motion mode, body mass index, type of reconstruction, type of prosthesis, and length of bone resection were independent risk factors for tumor prosthetic failure. A nomogram model was established using these significant predictors, with a concordance index of 0.77 and a favorable consistency between predicted and actual prosthetic failure rate according to the internal validation, indicating that the nomogram model had acceptable predictive accuracy. CONCLUSION: The prediction model identifies high-risk patients for whom attached preventive measures are required. Future studies regarding reduction in incidence of prosthetic failure should attach importance to these high-risk patients.

The effects of length of femoral stem on aseptic loosening following cemented distal femoral endoprosthetic replacement in tumour surgery.

PURPOSE: Aseptic loosening is a common prosthetic failure mode. The purpose of this study was to identify dose-response relationship between length of femoral stem and aseptic loosening. METHODS: We collected data of patients who underwent distal femoral prosthetic replacements at our institution from 2001 to 2017. Cox regression and two-piecewise regression model were used to analyze the associations between stem length and aseptic loosening. RESULTS: Significant association of length of femoral stem with aseptic loosening was observed in multivariate model and a non-linear relationship could be found from the smoothed curve. In two-piecewise model, an inflection point was calculated to be 143 mm. On the left of the inflection point, every 1 mm increase in the length of stem indicated that the risk of aseptic loosening could be reduced by 6%. CONCLUSION: There was a significant non-linear relationship between the length of femoral stem and aseptic loosening, and the inflection point was 143 mm.

Network meta-analysis of knee outcomes following anterior cruciate ligament reconstruction with various types of tendon grafts.

PURPOSE: Various grafts were selected for restoring knee stability and regaining pre-injury activity levels after anterior cruciate ligament (ACL) rupture. This review aimed to compare the short-term knee outcomes of different tendon grafts for primary ACL reconstruction (ACLR). METHODS: Databases of PubMed, Embase, and CENTRAL were retrieved for identifying the published RCT comparing the short-term (≤ 2 years) knee outcomes of different tendon grafts for ACLR. The main outcomes include the International Knee Documentation Committee (IKDC) subjective and objective scores, side-to-side difference on knee laxity, Lachman test, pivot-shift test, Lysholm score, Tegner score, all recorded complications and graft re-ruptures. RESULTS: A total of 32 trials involving 2962 patients and 17 grafts were included. Superior IKDC subjective score was found for quadriceps tendon autograft (QTB) when compared with autografts including bone-patellar tendon-bone (BPTB), four-strand hamstring tendon (4S-HT), and double-bundle HT. The 4S-HT autograft was associated with poorer anteroposterior and rotational knee stability than the BPTB autograft. Artificial ligament also was found to provide lower knee stability compared with the autografts including the BPTB, patellar tendon, 4S-HT, 4S-HT with preserved tibial insertion, 6S-HT, and four-strand semitendinosus tendon. Additionally, the BPTB allograft showed a statistically higher knee laxity than 6S-HT allograft, while no difference was found between the genuine autografts and non-irradiated allografts. CONCLUSIONS: QTB was recommended to be used even over the BPTB and 4S-HT autografts. BPTB autograft was more effective on restoring the knee stability than 4S-HT autograft. Non-irradiated allografts could be safely used as alternatives to autografts. However, artificial ligaments were not recommended for primary ACLR for significantly increased risk of knee laxity.

Outcome of segmental prosthesis reconstruction for diaphyseal bone tumors: a multi-center retrospective study.

BACKGROUND: The optimal reconstructive method after diaphyseal malignant bone tumor resection remains controversial. This multicenter clinical study was designed to investigate the clinical value and complications of segmental prosthesis in the repair of diaphyseal defects. METHODS: We present 49 patients from three clinical centers treated with wide resection for primary or metastatic bone tumors involving the diaphysis of the femur, tibia, humerus, or ulna, followed by reconstruction using a modular intramedullary segmental prosthesis. RESULTS: Enrolled patients included 23 men and 26 women with a mean age of 63.3 years. Of these, seven patients had primary bone tumors and 42 patients had metastatic lesions. At the mean follow-up of 13.7 months, 17 patients were alive, 31 patients were deceased due to tumor progression, and one patient was dead of another reason. There were eight nononcologic complications (two with radial nerve injury, three with delayed incision healing, two with aseptic loosening in the proximal humerus prosthetic stem and one with structural failure) and three oncologic complications (three with primary tumor recurrence) among all patients. The incidence of complications in primary tumor patients (4/7, 57.1%) was higher than that in patients with metastatic tumors (7/42, 16.7%) (p = 0.036). Aseptic loosening and mechanical complications were not common for patients with primary tumors, although the reconstruction length difference was statistically significant (p = 0.023). No statistically significant differences were observed in limb function, while the mean musculoskeletal tumor society score was 21.2 in femora, 19.6 in humeri, and 17.8 in tibiae (p = 0.134). CONCLUSIONS: Segmental prostheses represent an optional method for the reconstruction of diaphyseal defects in patients with limited life expectancy. Segmental prostheses in the humerus experienced more complications than those used to treat lesions in the femur.

Development and validation of a prognostic nomogram for the overall survival of patients living with spinal metastases.

INTRODUCTION: The primary goal of treatment in spinal metastasis is typically to extend patients' lifespan as much as possible, and optimally to relieve the symptoms and so improve quality of life. It is crucial to avoid over- or under-treatment, according to each patient's individual situation. Thus, this study aimed to identify significant prognostic factors for patients living with metastatic spine disease, and create a new nomogram for the prediction of survival rates. METHODS: Data from patients who had undergone operations for spinal metastasis between 2005 and 2016 were retrieved retrospectively, and randomized into training (70%) and validation groups (30%). A selection of pre-operative factors was analyzed using univariable and multivariable COX model for the training group. A nomogram was then developed using significant predictors in multivariable analysis. Accuracy was validated using a concordance index (C-index) and calibration curve for the training and validation groups, respectively. RESULTS: A total of 244 participants were enrolled, including 171 in the training group and 73 in the validation group. Primary tumor, Frankel Grade, Karnofsky Performance Score (KPS) and adjuvant therapy were found to be significant for predicting survival rates. A nomogram was developed by utilizing these predictors. The C-indexes for the two groups were 0.711 and 0.703 respectively. Moreover, a favorable consistency between the predicted and actual survival probabilities was demonstrated using calibration curves. CONCLUSIONS: A user-friendly nomogram model for facilitating medical procedures during clinical encounters was established to aid clinical decision making for individual patients.

Comparison of outcomes of 2 surgical treatments for proximal humerus giant cell tumors: a multicenter retrospective study.

BACKGROUND: The incidence of giant cell tumors in the proximal humerus is low. We evaluated 2 surgical treatments for giant cell tumors of the proximal humerus and postoperative upper-extremity function. METHODS: This study retrospectively analyzed the clinical data of 27 cases of giant cell tumors of the proximal humerus at 4 Chinese medical centers specializing in bone oncology collected between January 2002 and June 2015. All patients were followed up for more than 2 years. The surgical procedures performed for treatment included curettage in 14 patients and segmental resection in 13. The Campanacci grade, occurrence of pathologic fracture, surgical method, complications, and Musculoskeletal Tumor Society score were recorded for each cohort. RESULTS: The recurrence rate was 7.1% in the curettage group and 15.4% in the segmental resection group. Other postoperative complications occurred in 4 patients with segmental resection, including resorption of the osteoarticular allograft in 2, subluxation of the glenohumeral joint in 1, and prosthetic loosening and exposure in 1. A significant difference in postoperative upper-extremity function was noted between the 2 groups (P < .001). CONCLUSIONS: Postoperative upper-extremity function in the curettage group was significantly better than that in the segmental resection group. Segmental resection and reconstruction with a large segmental osteoarticular allograft were considered unadvisable. We suggest that extensive curettage should be selected to treat proximal humerus giant cell tumors as much as possible.

Rare variants of Bosworth fracture-dislocation: Bosworth fracture-dislocation with medial malleolus adduction type fracture.

Bosworth ankle fracture-dislocation is rare, known to be an irreducible type of ankle injury, with a high incidence of complication. We present two cases of even rarer variants of Bosworth ankle fracture-dislocation. The first case is a type of supination external rotation adduction, and the second case is a type of supination external rotation adduction. These types have not been described before. In both of the cases we failed to achieve close reduction, and therefore proceeded with emergency surgeries, with open reduction and internal fixation. Both of the cases were performed with a postero-lateral approach to reduce the dislocations, and fix the fractures successfully. Unfortunately in one of the cases, acute compartment syndrome developed post-surgically. However, both cases showed good functional outcomes.

Undisplaced subtle ligamentous Lisfranc injuries, conservative or surgical treatment with percutaneous position screws?

PURPOSE: Undisplaced subtle ligamentous Lisfranc injuries are easy to miss or underestimate, and many cases are treated without surgical fixation. It has not yet widely known whether conservative treatment for undisplaced subtle ligamentous Lisfranc injuries may lead to a poor outcome. The purpose of this study is to compare the outcomes of conservative versus surgical management (percutaneous position screw) of undisplaced subtle ligamentous Lisfranc injury. METHODS: We analysed 61 cases in this retrospective study, including 38 males and 23 females. Forty-one patients were managed conservatively, while 20 patients received surgical treatment involving minimal invasive percutaneous position screw. American orthopaedic foot &ankle society (AOFAS), foot function index (FFI, including FFI disability, FFI pain score and activity limitation scale) scores, Maryland foot score and short form-36 (SF-36) were recorded and compared after a follow-up of 10-16 months (average 12.3). RESULTS: Patients in the surgical management group had higher scores in all evaluation methods (p < 0.05). The complications in the conservative management group had higher incidence, mainly including secondary diastasis (34.1% vs. 5.0%), joint stiffness after 3 months (82.9% vs. 0%), and secondary arthrodesis (12.2% vs. 0%). The highest rate of complication in surgical management group was temporary forefoot pain (55.0%). CONCLUSION: The results of this study suggest that the outcomes of the surgical management with percutaneous position screw fixation are better than the conservative management to treat undisplaced subtle ligamentous Lisfranc injuries. This study can serve as a resource for orthopaedic surgeons in recognizing and managing such injuries.

Prognostic effect of factors involved in revised Tokuhashi score system for patients with spinal metastases: a systematic review and Meta-analysis.

BACKGROUND: Cancer patients' survival time has obviously improved, with the development of systemic treatment techniques. However, the probability of metastases to the vertebrae has also been increased which makes some adverse effects on patients' quality of life. The prediction of survival plays a key role in choosing therapeutic modality, and Tokuhashi Score was established as one of the most commonly used predictive systems for spinal metastases. Thus, this study was conducted to identify the prognostic effect of factors involved in revised Tokuhashi Score (RTS). METHODS: Two investigators independently retrieved relevant literature on platforms of PubMed, Embase and Cochrane Library. We identified eligible studies through title/abstract and full-text perusing. Data was extracted including general information of studies, participants' characteristics, therapeutic modality, overall survival and prognostic effect of factors. Hazard ratio (HR) for each factor was synthesized if available through fixed- or random-effect models as appropriate. RESULTS: A total of 63 eligible studies with 10,411 participants were identified. Overall, cases with thyroid cancer had the highest survival rate, while the ones with non-small cell lung cancer and hepatocellular carcinoma lived for the shorted survival time. Performance status, bone metastasis, number of involved vertebrae, visceral metastasis, primary tumor and neurological status were regarded as significant predictors in 71.4, 40.0, 18.2, 63.4, 73.1 and 44.7% of the involved studies respectively. Thirty-eight articles were included in meta-analysis, and prognostic effects of five factors (apart from primary tumor) were analyzed. Factors were all proved to be significant except comparisons between KPS (Karnofsky Performance Status) 10-40 VS. 50-70 and single VS. multiple spinal metastases. CONCLUSION: All factors of RTS were significant on prognosis predicting and should be considered when choosing therapeutic modality for spinal metastases. What's more, we believe that more accurate prognosis may be obtained after removal of the cut-offs for KPS 10-40 VS. 50-70 and single VS. multiple involved vertebrae.

Intercalary prosthetic reconstruction for pathologic diaphyseal humeral fractures due to metastatic tumors: outcomes and improvements.

BACKGROUND: There is a high aseptic loosening rate for intercalary prosthetic reconstruction for malignant tumors. We evaluated outcomes and complications of intercalary prosthetic reconstruction for pathologic diaphyseal humeral fractures and report the application of an extracortical plate that can prevent early loosening. METHODS: We retrospectively analyzed 9 patients who underwent intercalary prosthetic reconstruction for pathologic diaphyseal humeral fractures secondary to metastatic diseases between March 2011 and September 2017. Procedures were intercalary prosthetic reconstruction in 4 patients (group A) and an implanted intercalary prosthesis with a plate in 5 patients (group B). Operative time, blood loss, complications, and functional score were noted. RESULTS: Mean operative time for group A and B was 80 ± 14 and 94 ± 5 minutes, respectively; blood loss was 115 ± 26 and 120 ± 31 mL respectively; and follow-up was 11.5 ± 10.1 and 6.2 ± 4.4 months, respectively. At final follow-up, all patients in group A had died, and 3 patients in group B had died; mean survival was 11.5 ± 10.1 and 9.3 ± 1.2 months, respectively. The mean postoperative Musculoskeletal Tumor Society score was 24.5 ± 2.4 and 26.2 ± 0.8, respectively. The mean postoperative American Shoulder and Elbow Surgeons score was 85.5 ± 4.20 and 87 ± 2.6, respectively. There were no significant differences between the 2 groups (P > .05). There was 1 aseptic loosening and 1 radial nerve injury in group A; there were no complications in group B. CONCLUSIONS: The intercalary prosthesis yielded satisfactory outcomes in patients with pathologic diaphyseal humeral fractures, and an extracortical plate can prevent early aseptic loosening.

Bibliometric study of the orthopaedic publications from China.

PURPOSE: We aimed to investigate the status quo of orthopaedic publications from China and characterize the most-cited articles to provide valuable insights for orthopaedists. METHODS: PubMed and Embase databases were used to search for Chinese orthopaedic publications from 1997 to 2017 to determine the growing pattern of Chinese research globally. Then Web of Science database was searched for articles with most citations in all journals included in the Journal Citation Report 2016 under the category of "orthopaedics" for the last five years, and the total numbers of articles in the last three respective years were also analyzed. RESULTS: The number of publications published in PubMed and Embase during the last 20 years ranged from 218 to 6836, and year 2002 had the biggest growth rate of 59.15% and 2014 had the biggest growth value of 1203, comparing with previous years. Fifty-three articles were selected as the most-cited ones for the last five years. European Spine Journal and West China Hospital are the journal and institution that published the most high-impact articles. Majority of the articles (47%) were meta-analysis, and 6 RCTs were identified in a total of 11 clinical articles. Most high-cited clinical articles or meta-analyses were classified as level of evidence of I (41.67%).A total of 1238 articles, 1264 articles, and 1225 articles in the field of orthopedics from China were included in SCI for the last three years. CONCLUSION: The Chinese orthopaedic research grew rapidly in terms of number of publications in the last decades, and the quality of publications also improved in recent years.

Development and proposal of a scoring system for giant cell tumour of the bone around the knee.

PURPOSE: The purpose of this study was to provide the surgeons with effective and reliable guidelines for surgical decision-making by establishing a scoring system for giant cell tumour (GCTSS) based on evidence and expert opinion. METHODS: The modified Delphi technique and analytic hierarchy process were used to establish the GCTSS. The GCTSS was defined and classified based on different surgical methods using data from 207 patients collected retrospectively between October 2003 and December 2014. Finally, prospective data of 40 patients between December 2014 and October 2015 were used to analyze concordance between score categorization and experts' consensus on surgical procedure. RESULTS: A novel GCTSS included pathological fracture, cortical bone destruction, tumour size, and articular surface involved. The total scores ranged from 1 to 12 points. The strategy for each patient was decided: a total score of 1-4 suggested intralesional curettage alone for excellent post-operative function; 5-9 points indicated intralesional curettage with internal fixation for less surgery-related complications; and 10-12 points indicated prosthesis replacement for long-term local control. The κ-statistic for the predictive validity of total score was 0.611. The κ coefficient of each group represented moderate or substantial agreement, which was acceptable. The intraclass correlation coefficient for inter- and intra-observer reliability of total score was 0.831 and 0.740, respectively. CONCLUSIONS: The novel GCTSS is a comprehensive scoring system with content validity that can aid surgeons in assessing the aggressiveness or severity of giant cell tumour and might become a prognostic tool for surgical decision-making.

The prognostic value of elevated ezrin in patients with osteosarcoma.

Published studies researching the prognostic significance of ezrin expression in patients with osteosarcoma are inconclusive and heterogeneous. We conducted a meta-analysis to assess its prognostic value more precisely. The hazard ratios with corresponding 95 % confidence intervals were calculated to evaluate the effects. Five studies with 318 osteosarcoma patients were included to estimate the relationship between ezrin and disease-free survival, and ezrin and overall survival. Compared with osteosarcoma patients with low or negative ezrin expression, patients with high ezrin expression tended to be associated with lower disease-free survival, but the difference was not significant. However, patients with high ezrin expression were obviously associated with lower overall survival. Therefore, the findings from this systematic review suggest that ezrin expression is an effective biomarker of prognosis in patients with osteosarcoma.

Limitations and modifications in the clinical application of calcium sulfate.

Calcium sulfate and calcium sulfate-based biomaterials have been widely used in non-load-bearing bone defects for hundreds of years due to their superior biocompatibility, biodegradability, and non-toxicity. However, lower compressive strength and rapid degradation rate are the main limitations in clinical applications. Excessive absorption causes a sharp increase in sulfate ion and calcium ion concentrations around the bone defect site, resulting in delayed wound healing and hypercalcemia. In addition, the space between calcium sulfate and the host bone, resulting from excessively rapid absorption, has adverse effects on bone healing or fusion techniques. This issue has been recognized and addressed. The lack of sufficient mechanical strength makes it challenging to use calcium sulfate and calcium sulfate-based biomaterials in load-bearing areas. To overcome these defects, the introduction of various inorganic additives, such as calcium carbonate, calcium phosphate, and calcium silicate, into calcium sulfate is an effective measure. Inorganic materials with different physical and chemical properties can greatly improve the properties of calcium sulfate composites. For example, the hydrolysis products of calcium carbonate are alkaline substances that can buffer the acidic environment caused by the degradation of calcium sulfate; calcium phosphate has poor degradation, which can effectively avoid the excessive absorption of calcium sulfate; and calcium silicate can promote the compressive strength and stimulate new bone formation. The purpose of this review is to review the poor properties of calcium sulfate and its complications in clinical application and to explore the effect of various inorganic additives on the physicochemical properties and biological properties of calcium sulfate.