Why and How Often Is Revision Surgery Necessary after First Metatarsophalangeal Joint Arthrodeses? A Cohort of 120 Consecutive Cases

Background: Little is known about the rate and reasons for revision after primary Metatarsophalangeal (MTP1) arthrodesis with the latest implants. While it is commonly assumed that nonunion accounts for most reoperations, we hypothesized that malposition is the leading cause of revision. The aim of this study was to determine the rate and reasons for revision after MTP1 arthrodesis using cup- and cone-reamers and the latest locking plate technology. Method: Between 2015 and 2017, 120 consecutive MTP1 fusions in 114 patients were performed with a low profile, pre-contoured titanium dorsal locking plate and a plantar metatarsophalangeal screw. The rate and reasons for revision within a minimum one-year follow-up period (average 16 months [12 - 26]) after index procedures were documented and analyzed. The revision was defined as any reoperation following the index procedure excluding hardware removal. Results: Seventeen of 120 feet (14%) underwent revision. Four patients developed a nonunion (3.3%) and needed revision, and 11 feet (9%) required revision for painful malposition;insufficient extension and excessive valgus accounted for the majority. Two patients required medial sesamoidectomy. No infection or wound healing problems occurred. Twelve patients requested hardware removal. Conclusions: Nonunion revision rate after MTP1 fusion with the latest locking plate technology is low. The leading cause of revision is malposition followed by nonunion. Excessive valgus and insufficient extension account for most symptomatic malposition. A recommendation of 0 - 10 degrees of valgus in the horizontal plane may contribute to diminishing revision rates;no conclusions could be drawn regarding an optimal position in the sagittal plane.

Atlantoaxial joint fusion using anterior transarticular screw fixation and bone grafting for atlantoaxial joint instability

Objective To evaluate the clinical application of atlantoaxial joint fusion using anterior transarticular screw fixation and bone grafting for atlantoaxial joint instability. Methods Twenty-three cases of atlantoaxial joint instability were

NEW VIEW OF CHARACTERISTIC ZONE CLASSIFICATION OF FUSION WELDING JOINT

A new view of characterstic zone classification of fusion welding joint has been put for-ward on the base of a number of metallograplic observations and researches. TLe characteristiczones of the joint include (1) homogenous mixture region (2)heterogerous mixture zone, (3)partically melting zone and (4) heat-affected zone. (1) and (2) consist of the weld metal. (2) and (3)compose the bond, the boundary betweer (2) and (3) is the fusion line Four kinds of characteristicappearences in the ' heterogenous mixture zone' are induced. The formation process of thecharcteristic zones is distussed in detail. The differences between authors' classification and W. F.Savage's one are compared, to hoping that the formation essence and composition feature of fusionwelding joint can be reasonably reflected.

Blue rubber blister nevus syndrome: A case report

BACKGROUND Blue rubber blister nevus syndrome(BRBNS)is a congenital,rare disease charac-terized by venous malformations of the skin and internal organs,affecting all systems throughout the body.The pathogenesis is unknown.There is no con-sensus on the treatment of BRBNS.Most of the previously reported cases were mild to moderate with a good prognosis,and this case was a critically ill patient with severe gastrointestinal hemorrhage,disseminated intravascular coagulation(DIC),and severe joint fusion that was different from previously reported cases.CASE SUMMARY An 18-year-old man with early onset of BRBNS in early childhood is reported.He presented with recurrent melena and underwent malformed phlebectomy and partial jejunectomy and ileal resection.The patient had melena before and after surgery.After active treatment,the patient's gastrointestinal bleeding improved.This was a case of atypical BRBNS with severe gastrointestinal bleeding and severe joint fusion,which should be differentiated from other serious joint lesions and provide clinicians with better understanding of this rare disease.CONCLUSION This case of critical BRBNS with gastrointestinal hemorrhage,DIC and severe joint fusion provides further understanding of this rare disease.

Multi-Model Fusion Framework Using Deep Learning for Visual-Textual Sentiment Classification

Multimodal Sentiment Analysis(SA)is gaining popularity due to its broad application potential.The existing studies have focused on the SA of single modalities,such as texts or photos,posing challenges in effectively handling social media data with multiple modalities.Moreover,most multimodal research has concentrated on merely combining the two modalities rather than exploring their complex correlations,leading to unsatisfactory sentiment classification results.Motivated by this,we propose a new visualtextual sentiment classification model named Multi-Model Fusion(MMF),which uses a mixed fusion framework for SA to effectively capture the essential information and the intrinsic relationship between the visual and textual content.The proposed model comprises three deep neural networks.Two different neural networks are proposed to extract the most emotionally relevant aspects of image and text data.Thus,more discriminative features are gathered for accurate sentiment classification.Then,a multichannel joint fusion modelwith a self-attention technique is proposed to exploit the intrinsic correlation between visual and textual characteristics and obtain emotionally rich information for joint sentiment classification.Finally,the results of the three classifiers are integrated using a decision fusion scheme to improve the robustness and generalizability of the proposed model.An interpretable visual-textual sentiment classification model is further developed using the Local Interpretable Model-agnostic Explanation model(LIME)to ensure the model’s explainability and resilience.The proposed MMF model has been tested on four real-world sentiment datasets,achieving(99.78%)accuracy on Binary_Getty(BG),(99.12%)on Binary_iStock(BIS),(95.70%)on Twitter,and(79.06%)on the Multi-View Sentiment Analysis(MVSA)dataset.These results demonstrate the superior performance of our MMF model compared to single-model approaches and current state-of-the-art techniques based on model evaluation criteria.

Study on fracture characteristic of welded high-density polyethylene pipe

Crack opening displacement(COD) was applied to characterize the fracture initiation of the tough high density polyethylene. Normal single side notched three point bend specimens and silica rubber replica techniques were used to study the characteristic COD of high density polyethylene pipe and its butt fusion joints including the weld fusion zone and heat affected zone at different temperature from -78 ℃ to 20 ℃ . Testing results show that the characteristic COD appears to depend on the structural features that are determined by welding process and the testing temperature. As the temperature is lowered, the characteristic COD of all zones studied decreases. Because the welding process significantly changes some structural feature of the material, characteristic COD of the weld fusion zone is the smallest one among those of the three zones. The results can be used for the engineering design and failure analysis of HDPE pipe.

Microstructure Characterization of the Fusion Zone of an Alloy 600-82 Weld Joint

Characterization of the microstructure of the fusion zone of an Alloy 600-82 weld joint was conducted, with focus on the weld residual strain distribution and the comparison of the microstructure of heat affected zone （HAZ） with that of cold worked alloy. Peak of the residual strain was observed to approach to the fusion boundary in HAZ while the strain increased from the top of the weld to the root. Strain distribution in the HAZ was found to be concentrated adjacent to grain boundaries （GBs）, with a peak of approximately three times of that in grain. Further, triple junctions of the GB appear to cause a higher strain concentration than single GBs. The microstructure of HAZ consists of partially tangled dislocations, which is different from slip bands of high density dislocations in cold worked alloy. This may cause a relatively higher intergranular cracking resistance of HAZ due to the difficulty in transferring tangled dislocations to GB in HAZ under deformation.