DFR-U-Net: Dual residual and feature fusion network for ulna and radius segmentation on dual-energy X-ray absorptiometry images.

BACKGROUND: Ulna and radius segmentation of dual-energy X-ray absorptiometry (DXA) images is essential for measuring bone mineral density (BMD). OBJECTIVE: To develop and test a novel deep learning network architecture for robust and efficient ulna and radius segmentation on DXA images. METHODS: This study used two datasets including 360 cases. The first dataset included 300 cases that were randomly divided into five groups for five-fold cross-validation. The second dataset including 60 cases was used for independent testing. A deep learning network architecture with dual residual dilated convolution module and feature fusion block based on residual U-Net (DFR-U-Net) to enhance segmentation accuracy of ulna and radius regions on DXA images was developed. The Dice similarity coefficient (DSC), Jaccard, and Hausdorff distance (HD) were used to evaluate the segmentation performance. A one-tailed paired t-test was used to assert the statistical significance of our method and the other deep learning-based methods (P < 0.05 indicates a statistical significance). RESULTS: The results demonstrated our method achieved the promising segmentation performance, with DSC of 98.56±0.40% and 98.86±0.25%, Jaccard of 97.14±0.75% and 97.73±0.48%, and HD of 6.41±11.67 pixels and 8.23±7.82 pixels for segmentation of ulna and radius, respectively. According to statistics data analysis results, our method yielded significantly higher performance than other deep learning-based methods. CONCLUSIONS: The proposed DFR-U-Net achieved higher segmentation performance for ulna and radius on DXA images than the previous work and other deep learning approaches. This methodology has potential to be applied to ulna and radius segmentation to help doctors measure BMD more accurately in the future.

Deep learning approach for automatic segmentation of ulna and radius in dual-energy X-ray imaging.

BACKGROUND: Segmentation of the ulna and radius is a crucial step for the measurement of bone mineral density (BMD) in dual-energy X-ray imaging in patients suspected of having osteoporosis. PURPOSE: This work aimed to propose a deep learning approach for the accurate automatic segmentation of the ulna and radius in dual-energy X-ray imaging. METHODS AND MATERIALS: We developed a deep learning model with residual block (Resblock) for the segmentation of the ulna and radius. Three hundred and sixty subjects were included in the study, and five-fold cross-validation was used to evaluate the performance of the proposed network. The Dice coefficient and Jaccard index were calculated to evaluate the results of segmentation in this study. RESULTS: The proposed network model had a better segmentation performance than the previous deep learning-based methods with respect to the automatic segmentation of the ulna and radius. The evaluation results suggested that the average Dice coefficients of the ulna and radius were 0.9835 and 0.9874, with average Jaccard indexes of 0.9680 and 0.9751, respectively. CONCLUSION: The deep learning-based method developed in this study improved the segmentation performance of the ulna and radius in dual-energy X-ray imaging.

[Closed folding apex manipulation combined with splinting for the treatment of double fractures of distal ulna and radius in children].

OBJECTIVE: To investigate specific technique and clinical effects of closed folding top consolidation maneuver combined with splint fixation maneuver for consolidation and cedar bark external fixation splint for the treatment of double fractures of distal ulna and radius in children. METHODS: From January 2017 to December 2019, 17 children with double fractures of distal ulna and radius were treated with closed folded apex consolidation maneuver, including 13 males and 4 females, aged from 4 to 11 years old with an average of (7.29±2.34) years old. The fractures were fixed with cedar bark splint and followed up for 6 months, and alignment of fracture was evaluated according to the latest X-rays by follow up, and function of the affected limbs was evaluated by Anderson forearm function evaluation criteria. RESULTS: Fifteen of 17 children were successfully reset immediately, and 2 children were successfully reset again. The average fixed time was (25.00±3.35) days. At 6 months of follow up, 12 patients got excellent results, 3 good, 2 fair, and 0 poor according to Anderson forearm function evaluation criteria. The position of all children were larger than 3/4, and 10 children were received anatomical reduction, alignment of 4 children was less than 10°, 3 children was less than 15°. No complications such as fracture displacement, nonunion, compartment syndrome, and forearm rotation dysfunction occurred. CONCLUSION: Restoration of distal radius double fracture in children with the combination of the closed folding and top fixation maneuver and splint fixation maneuver has advantages of higher success rate, lower complications, which could reduce operating difficultyand pain of patients.

Pulmonary thromboembolism after distal ulna and radius fractures surgery: A case report and a literature review.

BACKGROUND: Pulmonary thromboembolism (PTE) is a serious postoperative complication that can occur after a fracture. Generally, PTE is caused by the falling off of lower extremity deep vein thrombosis (LEDVT) after lower limb fracture surgery. LEDVT and PTE after upper extremity fracture surgery are very rare. PTE is one of the most common clinical causes of sudden death. Venous thromboembolism includes PTE and DVT. We experienced one case of LEDVT and PTE after distal ulna and radius fracture surgery. The purpose of our report is to raise awareness for orthopedic surgeons that PTE can occur after distal ulna and radius fracture surgery, and patients with high risk factors should be considered for prevention and treatment of thrombosis in a timely manner. CASE SUMMARY: We report a 51-year-old Chinese male who had severe fractures of the left distal ulna, radius and little finger after a motorcycle accident. The patient underwent external fixation, open reduction and internal fixation. On the third post-operative day, computed tomographic pulmonary angiography showed PTE. Doppler ultrasonography showed thrombus formation in the bilateral posterior tibial veins. After a period of anticoagulation therapy, on the 25th d after the PTE, computed tomographic pulmonary angiography showed that thrombus in both sides of the pulmonary artery disappeared. Furthermore, about 4 mo after the PTE, thrombosis in the deep veins of the lower limbs disappeared. About 1 year after the surgery, X-rays showed good fracture healing, and the function of the wrist joint recovered well. CONCLUSION: Though rare, PTE can occur after distal ulna and radius fracture surgery and patients with high risk factors should be considered for prevention and treatment of thrombosis in a timely manner.

Closed folding apex manipulation combined with splinting for the treatment of double fractures of distal ulna and radius in children / 中国骨伤

OBJECTIVE@#To investigate specific technique and clinical effects of closed folding top consolidation maneuver combined with splint fixation maneuver for consolidation and cedar bark external fixation splint for the treatment of double fractures of distal ulna and radius in children.@*METHODS@#From January 2017 to December 2019, 17 children with double fractures of distal ulna and radius were treated with closed folded apex consolidation maneuver, including 13 males and 4 females, aged from 4 to 11 years old with an average of (7.29±2.34) years old. The fractures were fixed with cedar bark splint and followed up for 6 months, and alignment of fracture was evaluated according to the latest X-rays by follow up, and function of the affected limbs was evaluated by Anderson forearm function evaluation criteria.@*RESULTS@#Fifteen of 17 children were successfully reset immediately, and 2 children were successfully reset again. The average fixed time was (25.00±3.35) days. At 6 months of follow up, 12 patients got excellent results, 3 good, 2 fair, and 0 poor according to Anderson forearm function evaluation criteria. The position of all children were larger than 3/4, and 10 children were received anatomical reduction, alignment of 4 children was less than 10°, 3 children was less than 15°. No complications such as fracture displacement, nonunion, compartment syndrome, and forearm rotation dysfunction occurred.@*CONCLUSION@#Restoration of distal radius double fracture in children with the combination of the closed folding and top fixation maneuver and splint fixation maneuver has advantages of higher success rate, lower complications, which could reduce operating difficultyand pain of patients.

Biomechanical characteristics of the distal radius fracture based on three-dimensional finite element model of ulna and radius / 中国组织工程研究

BACKGROUND: In recent years, most qualitative studies on the mechanism of distal radius fracture are limited to two-dimensional analysis, which is susceptible to many factors, resulting in unsatisfactory results The use of CT data to establish a three-dimensional finite element model can better evaluate human skeletal variation. OBJECTIVE: To establish a three-dimensional finite element model of the radius and ulna, to test the biomechanics of distal radius fracture and to study the mechanism of distal radius fracture. METHODS: Left upper limb of one 50-year-old healthy female was selected to obtain CT imaging data from distal humerus to middle carpal joint. The three-dimensional finite element model of radius and ulna was established by using three-dimensional finite element analysis software Ansys 16.0. The force load of wrist back extension, palm flexion, ulnar deviation, and radial deviation were simulated. The stress of each part ofthe model under different loads was observed and recorded. The fracture formation and crack direction of distal radius at different model angles were analyzed. RESULTS AND CONCLUSION: (1) When the wrist joint was in dorsal extension position, the compressive stress at the midpoint of the dorsal radial margin ofthe forearm pronation and forearm supination increased with the increase ofthe dorsal extension angle, the tension stress on the volar radius of the forearm pronation and forearm supination increased with the increase of the dorsal extension angle. (2) When the wrist joint was in the metacarpal flexion position, the tension stress at the midpoint of the dorsal radius of the forearm pronation and the forearm supination increased with the increase of the metacarpal flexion angle. The compressive stress on the volar radius of the forearm pronation and forearm supination increased with the increase of the palmar flexion angle. (3) When the forearm was pronated dorsiflexion and supinated metacarpal flexion, the radial crack first appeared on the side of the maximum tension on the surface of the distal radius at the junction of cancellous bone and dense bone, the fracture crack developed along the distal metacarpal to the proximal dorsal end and at an angle of 45 degrees to the bone axis. (4) When the forearm was pronated metacarpal flexion and supinated dorsiflexion, the radial crack first appeared on the side of the maximum tension on the surface of the distal radius at the junction of cancellous bone and dense bone, the fracture crack developed along the far back end to the proximal palmar side and at an angle of 45 degrees to the bone axis. (5) To conclude, with the force load on wrist dorsal extension, metacarpal flexion, ulnar deviation, and radial deviation, the fracture first occurs on the maximum surface tension side of the distal radius at the junction of cancellous bone and dense bone, the direction of the crack is related to the directions of shear stress and tension stress.

Mongolian osteopathy in the treatment of ulna-radius fractures: Finite element analysis of mechanical principle / 中国组织工程研究

BACKGROUND: Mongolian osteopathy is famous for the complicated manipulation and theoretical complexity. Combined with the finite element model of ulna-radius fractures, the analysis on the manipulation of osteopathy has not been reported at home and abroad. OBJECTIVE: To simulate the force of various ulna-radius fractures and establish the model of ulna-radius fractures, to analyze the effect, and to analyze the manipulation mechanism of Mongolian osteopathy on the corresponding fractures. METHODS: One 35-year-old volunteer was selected to obtain the CT image data of the right forelimb after signed the informed consent. The geometric model of the radius and ulna was established based on the parameters of bone tissue. The material mesh was divided, and the load parameters were assigned for analysis and calculation. Based on the common causes of Colles and Smith fractures, the osteopathy manipulation was evaluated by combined with “force to force” of Mongolian osteopathy. RESULTS AND CONCLUSION: (1) The stress distribution of the model of ulna-radius fractures is highly consistent with previous studies of the forearm. The mechanical models of Colles and Smith fractures were obtained in the direction of stress. After adjusting the mechanical parameters of bone, the fracture models of four different ages could be simulated. (2) These results indicate that the finite fracture model is feasible. Meta-analysis could simulate the ulna-radius fractures, and provide a manual reference for treating ulna-radius fractures with “force-to-force” theory in Mongolian osteopathy.