Topology Optimization Via Spatially-Varying TPMS.

Structural design with multi-family triply periodic minimal surfaces (TPMS) is a meaningful work that can combine the advantages of different types of TPMS. However, very few methods consider the influence of the blending of different TPMS on structural performance, and the manufacturability of final structure. Therefore, this work proposes a method to design manufacturable microstructures with topology optimization (TO) based on spatially-varying TPMS. In our method, different types of TPMS are simultaneously considered in the optimization to maximize the performance of designed microstructure. The geometric and mechanical properties of the unit cells generated with TPMS, that is minimal surface lattice cell (MSLC), are analyzed to obtain the performance of different types of TPMS. In the designed microstructure, MSLCs of different types are smoothly blended with an interpolation method. To analyze the influence of deformed MSLCs on the performance of the final structure, the blending blocks are introduced to describe the connection cases between different types of MSLCs. The mechanical properties of deformed MSLCs are analyzed and applied in TO process to reduce the influence of deformed MSLCs on the performance of final structure. The infill resolution of MSLC within a given design domain is determined according to the minimal printable wall thickness of MSLC and structural stiffness. Both numerical and physical experimental results demonstrate the effectiveness of the proposed method.

Customizing Anterolateral Thigh Flap With Magnetic Resonance Angiography Differential Subsampling With Cartesian Ordering Imaging for Individualized Reconstruction of Extremity Defects.

INTRODUCTION: Magnetic resonance angiography (MRA) with the differential subsampling with cartesian ordering (DISCO) imaging technique is rarely used in anterolateral thigh (ALT) flap. In our series, MRA DISCO imaging technique is used as a tool to customize ALT flaps. The aim of this study was to report the accuracy of cutaneous perforators identified by the MRA DISCO imaging. METHODS: Nineteen patients underwent the MRA DISCO imaging for perforator mapping before the ALT flap transfer. A total of 38 ALT regions were studied on the MRA DISCO images. Flap thinning was performed under the guidance of MRA DISCO imaging. RESULTS: The lateral circumflex femoral artery (LCFA) most commonly stems from the deep femoral artery (84.2%), followed by the common femoral artery (15.8%). The average number of perforator vessels per LCFA was 10.2 ± 1.7. The distinct oblique branch was observed in 16 out of the 38 ALT regions (42.1%). Among the 19 ALT flaps harvested, 5 were septocutaneous perforator flaps and 14 musculocutaneous perforator flaps. Ten were harvested based on the descending branch, and 3 used the oblique branch as the flap vascular pedicle. In addition, the displayed course and types of perforator vessels on the DISCO images of the 18 skin flaps were consistent with the intraoperative findings, with an accuracy of 94.7%. CONCLUSIONS: The state of the cutaneous perforators of LCFA can be identified on the MRA DISCO images. The 3D-CE-MRA DISCO imaging is a practical method, which can ameliorate the design and customization of ALT flap for an individualized reconstruction.

Effect of percutaneous and arthroscopically assisted osteosynthesis of talar body fractures.

BACKGROUND: Talar fractures are relatively uncommon, and the complex anatomy of the talus impedes their visualization, reduction, and fixation without performing an arthrotomy or osteotomy. To date, few studies have evaluated the complications of arthroscopically assisted percutaneous talar osteosynthesis. This clinical retrospective study aimed to investigate the effectiveness of this procedure according to the complications and functional outcomes. METHODS: Arthroscopically assisted percutaneous talar osteosynthesis was performed in 15 patients (10 men and 5 women) with 16 fractures (one bilateral). The mean patient age was 31 years (range, 14-52 years). The Sneppen classification of the fractures was type II in 14 cases and type III in 2 cases. RESULTS: Fifteen patients were followed up for 36 months on average (range, 18-65 months). No skin infection, osteomyelitis, or skin necrosis was observed in any patient. During the follow-up, no bony non-union or delayed union was found. At the final follow-up, 2 out of the 15 patients (13.3%) had peri-talar osteoarthritis. The ankle-hindfoot pain was absent in 11 patients (12 ankles) and mild in 4 patients. Based on the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale, functional results were excellent in 7 ankles and good in 9 ankles. The mean AOFAS ankle-hindoot score of the patients was 85.7 (range, 79-93). CONCLUSION: Arthroscopically assisted percutaneous talar osteosynthesis is a reliable and feasible technique that yields good clinical outcomes.

Plantar and dorsal approaches for excision of morton's neuroma: a comparison study.

BACKGROUND: Morton's neuroma is a painful enlargement of the plantar digital nerve between the metatarsal heads that causes pain of the forefoot. Several approaches have been used to treat Morton's neuroma, each of them having distinct advantages and disadvantages. OBJECTIVES: The purpose of this study was to investigate and compare the clinical outcomes of neurectomy in the treatment of Morton's neuroma through plantar and dorsal approaches. MATERIALS AND METHODS: A total of 20 patients with a mean age of 48.5 ± 13.0 years (range: 19-66 years) who underwent excision of a Morton's neuroma that did not respond to conservative treatment were retrospectively analysed from June 2014 to June 2021. All the neurectomies were performed using a plantar or dorsal approach. Outcomes were evaluated using visual analogue scale (VAS) scores, American Orthopedic Foot and Ankle Society (AOFAS) scores, the Foot and Ankle Ability Measure (FAAM), and complications. The appearance index (AI) was also used to assess the influence of foot appearance on the quality of life after surgery. RESULTS: Eight patients underwent neurectomy by the dorsal approach, and 12 patients underwent neurectomy by the plantar approach. The average follow-up time was 28.9 ± 12.9 months (range: 15-72 months). No statistically significant difference was found between the dorsal and plantar approach groups with respect to postoperative pain measured by the VAS score. The postoperative AOFAS scores and FAAM outcomes were not significantly different between the groups. The complications reported in the dorsal approach group were significantly less than those of the plantar group, mainly discomfort in wearing shoes. The AI of the plantar group and the dorsal group were significantly different. CONCLUSION: The excision of the Morton's neuroma by both the dorsal and plantar approach resulted in satisfactory outcomes. However, the foot appearance after surgery by the plantar approach had less influence on the quality of life than that using the dorsal approach. Our recommendation is that surgeons should choose the approach they are most familiar with and with which they are most confident in performing. In addition, the plantar approach is recommended if the patient needs a better appearance.

Experimental Realization of Atomic Monolayer Si9 C15.

Monolayer Six Cy constitutes an important family of 2D materials that is predicted to feature a honeycomb structure and appreciable bandgaps. However, due to its binary chemical nature and the lack of bulk polymorphs with a layered structure, the fabrication of such materials has so far been challenging. Here, the synthesis of atomic monolayer Si9 C15 on Ru (0001) and Rh(111) substrates is reported. A combination of scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), scanning transmission electron microscopy (STEM), and density functional theory (DFT) calculations is used to infer that the 2D lattice of Si9 C15 is a buckled honeycomb structure. Monolayer Si9 C15 shows semiconducting behavior with a bandgap of ≈1.9 eV. Remarkably, the Si9 C15 lattice remains intact after exposure to ambient conditions, indicating good air stability. The present work expands the 2D-materials library and provides a promising platform for future studies in nanoelectronics and nanophotonics.

A Novel Anatomic Reconstruction for Posterior Tibialis Tendon in Treatment of Flexible Adult-Acquired Flatfoot Deformity.

OBJECTIVE: To present a novel approach for the anatomic reconstruction of the posterior tibialis tendon (PTT) in restoring plantar insertions and evaluate its efficiency in treating flexible adult-acquired flatfoot deformity (AAFD) caused by PTT dysfunction. METHODS: For AAFD treatment, a novel PTT reconstruction method was presented. The current study involved 16 patients, including three men, and 13 women, from August 2017 to July 2019. The mean age was 43.2 ± 15.1 years (21-64 years). The innovative PTT repair method was used on all patients. The treatment involved performing a traditional Flexor Digitorum Longus (FDL) transfer in the navicular tuberosity and suturing the plantar insertions to FDL as tension was applied to tighten the plantar structures of the foot. The results were retrospectively analyzed. The clinical outcome was assessed using the pain visual analogue scale (VAS), the satisfaction VAS, and the American Orthopedic Foot and Ankle Society ankle-hindfoot scale (AOFAS-AH). Isokinetic testing was performed using a dynamometer at 60°/s and 120°/s for inversion/eversion and plantarflexion/dorsiflexion, respectively, to determine the mean peak torque. Radiographic measurements were employed to assess the outcomes. RESULTS: Bone surgeries combined with the modified anatomic PTT reconstruction were performed on patients with medializing calcaneal osteotomy in 12 (75%) patients and subtalar joint fusion in four (25%) patients. The branch linking to the plantar insertions was detected in every case, with an average width of 3.5 ± 0.8 mm (3.1-4.3 mm). All patients were followed up for the mean of 16.8 ± 1.8 months (range, 15-20 months). The average postoperative functional scores, including pain VAS, satisfaction VAS, total AOFAS-AH, and all AOFAS-AH sub-scales, steadily improved during the follow-up. In the last follow-up, isokinetic testing revealed no loss of plantarflexion strength (p = 0.350 and 0.098) and significant improvement in the inversion strength (p = 0.007 and 0.008) in the operated ankles at 60°/s and 120°/s. Radiographic outcomes, particularly the talar head uncovering, improved significantly after more than a year (p < 0.001 for all). CONCLUSIONS: The novel technique for PTT reconstruction in restoring the plantar insertions serves as an effective procedure in treating AAFD caused by PTT dysfunction in terms of delivering a consistent improvement in ankle inversion strength, medial longitudinal arch restoring, and satisfactory clinical outcomes.

Plantar approach for treatment of brachymetatarsia: A novel approach with an aesthetic consideration.

In the past, open osteotomy was always performed through a dorsal approach in the surgical treatment of brachymetatarsia, which created scar formation on the dorsal skin, subsequently resulting in dissatisfaction with cosmetic results. In this study, we provided a plantar approach to avoid forming scars on the dorsal side. A retrospective review was conducted in nine patients (13 feet) with brachymetatarsia treated with an open osteotomy and gradual bone lengthening through a plantar approach. Visual analogue scale (VAS) was used to evaluate the satisfaction of foot appearance, and we designed a questionnaire called appearance index (AI) to assess the influence of foot appearance on quality of life after surgery. The complications were also recorded during the follow-up. The patients were followed up for 34.8 ± 23.7 months. All cases were healed with a time of 64.4 ± 7.1 days and a healing index of 44.1 ± 7.8 d/cm. Satisfaction VAS for foot appearance improved from a preoperative score of 1.7 ± 1.3 points to a postoperative score of 9.3 ± 0.5 points. The AI improved from a preoperative score of 9.2 ± 0.8 points to a postoperative score of 0.6 ± 0.7 points. Complications were observed in three feet (23.1%), but none was related to the plantar approach. In conclusion, the plantar approach for metatarsal osteotomy and pins fixation was a safe and efficient technique with a satisfactory cosmetic result for the patients. No complications related to the novel approach, such as neurovascular injury, were reported.

A Support-Free Infill Structure Based on Layer Construction for 3D Printing.

The design of the light-weight infill structure is a hot research topic in additive manufacturing. In recent years, various infill structures have been proposed to reduce the amount of printing material. However, 3D models filled with them may have very different structural performances under different loading conditions. In addition, most of them are not self-supporting. To mitigate these issues, a novel light-weight infill structure based on the layer construction is proposed in this article. The layers of the proposed infill structure continuously and periodically transform between triangles and hexagons. The geometries of two adjacent layers are controlled to be self-supporting for different 3D printing technologies. The machine code (Gcode) of the filled 3D model is generated in the construction of the infill structure for 3D printers. That means 3D models filled with the proposed infill structure do not need an extra slicing process before printing, which is time consuming in some cases. Structural simulations and physical experiments demonstrate that our infill structure has comparable structural performance under different loading conditions. Furthermore, the relationship between the structural stiffness and the parameters of the infill structure is investigated, which will be helpful for non-professional users.

Profile Evolution and Cross-Process Collaboration Strategy of Bearing Raceway by Centerless Grinding and Electrochemical Mechanical Machining.

Roundness is one of the most important evaluation indexes of rotary parts. The formation and change of roundness in the machining of parts is essentially the formation and genetic process of profile. Centerless positioning machining is one of the main surface finishing methods of rotary parts. The rounding mechanism of centerless positioning machining determines its unique roundness profile formation and genetic characteristics. How to eliminate the roundness error of centerless positioning machining has become one of the important issues in the research of high-precision rotary part machining. This paper explores the influence of process parameters on the roundness error from the perspective of profile evolution during centerless grinding and electrochemical mechanical machining, with the aim of providing a cross-process collaboration strategy for improving bearing raceway accuracy. Through an experiment of centerless grinding, the influence law and mechanism of process parameters on the profile are discussed. On this basis, electrochemical mechanical machining experiments are designed to explore the variation rules and mechanisms of different profile shapes in the machining process. The cross-process collaboration strategy is studied, and reasonable parameters of centerless grinding and electrochemical mechanical machining are determined. The results show that in the centerless grinding stage, increasing the support plate angle can form a multiple-lobe profile with high frequency within a wide range of process parameters. Electrochemical mechanical machining can effectively smooth the high-frequency profile and appropriately expanding the cathode coverage can improve the roundness error and reduce the requirement of initial accuracy of a multiple-lobe profile workpiece to a certain extent. Therefore, the combined machining technology of "centerless grinding + electrochemical mechanical machining" provides an efficient technical means to realize the precision machining of rotary parts such as bearing raceways.

Mimical reconstruction and aesthetic repair of the nail after resection of subungual melanocytic nevus.

BACKGROUND: This study aimed to report the outcomes of mimical reconstruction and aesthetic repair of the nail. METHODS: When the pigmented bands were more than 1/2 the width of the whole nail, mimical reconstruction of the nail was performed, with a lateral toe pulp island flap covering the wound via the subcutaneous channel. If the pigmented bands were 1/4 to 2/5 the width of the entire nail, aesthetic repair of the nail was carried out by split-thickness excision under a microscope. RESULTS: The average age of patients at the time of surgery was 14.5 years. Five patients had lesions on their toes, while three had lesions on their fingers. There were no post-operative complications. All toenails of the five patients who had undergone mimical reconstruction exhibited a well-settled flap. The nails of the three patients who underwent aesthetic repair displayed no nail malnutrition or deformity, and all nails had an aesthetic appearance. CONCLUSIONS: Both mimical reconstruction and aesthetic repair of the nail following resection of subungual melanocytic nevus are reliable and feasible. The "like tissue" repairs of complex nail defects appear to be satisfactory. All patients had excellent aesthetic outcomes. LEVEL OF EVIDENCE: V.

Efficacy and safety of Shenfu injection combined with sodium nitroprusside in the treatment of chronic heart failure in patients with coronary heart disease: A protocol of randomized controlled trial.

BACKGROUND: Coronary heart disease is a serious cardiovascular disease. There is coronary atherosclerosis, resulting in lumen stenosis, blockage, and then the symptoms of insufficient blood supply and hypoxia in the myocardium. Chronic heart failure is a kind of syndrome with abnormal ventricular filling and ejection function, which is the final stage of the development of coronary heart disease. At present, the treatment plan of Western medicine can significantly reduce the hospitalization rate, but it is still not satisfactory for the prognosis and mortality of patients. Shenfu injection has advantages in the treatment of heart failure in patients with coronary heart disease, but there is a lack of standard clinical studies to verify it, so the purpose of this randomized controlled study is to evaluate the efficacy and safety of Shenfu injection combined with sodium nitroprusside in the treatment of chronic heart failure in patients with coronary heart disease. METHODS: This is a prospective randomized controlled trial to study the efficacy and safety of Shenfu injection combined with sodium nitroprusside in the treatment of chronic heart failure in patients with coronary heart disease. The patients will be randomly divided into a treatment group and the control group according to 1:1, in which the treatment group is treated with Shenfu injection combined with sodium nitroprusside, and the control group is treated with sodium nitroprusside alone. Both groups will be treated with standard treatment for 7 days and followed up for 30 days to pay attention to their efficacy and safety indexes. The observation indexes include TCM syndrome score, N-terminal pro-brain natriuretic peptide, left ventricular ejection fraction, brain natriuretic peptide, left ventricular end-systolic diameter, left ventricular end-diastolic diameter, stroke volume, adverse reactions and so on. We will use SPSS 25.0 software for data analysis. DISCUSSION: This study will evaluate the efficacy and safety of Shenfu injection combined with sodium nitroprusside in the treatment of chronic heart failure in patients with coronary heart disease. The results of this experiment will provide a clinical basis for Shenfu injection combined with sodium nitroprusside in the treatment of chronic heart failure in coronary heart disease. TRIAL REGISTRATION: DOI 10.17605/OSF.IO/4KNG3.

[Significance of the ratio of C-reactive protein to prealbumin in patients with traumatic brain injury].

OBJECTIVE: To investigate the value of serum C-reactive protein/prealbumin ratio (CRP/PA) in predicting the disease progression of adult patients with traumatic brain injury. METHODS: A prospective study was conducted. Patients with traumatic brain injury who were over 18 years old and were followed up for more than 72 hours admitted to the department of emergency of Huashan North Hospital Affiliated to Fudan University from May 2018 to December 2019 were enrolled. The levels of serum CRP, PA were measured immediately after injury and at 6, 24, 48 and 72 hours after injury, and the CRP/PA ratio was calculated. Glasgow coma score (GCS) was dynamically measured and head CT was reviewed regularly. If the GCS decreased by more than 3 and/or the intracranial injury was aggravated by CT scan within 72 hours after injury, the patients were included in the aggravating group. If there were no above changes, they were included in the stable group. The differences of each index between the two groups were compared, and the receiver operating characteristic (ROC) curve was drawn to evaluate the predictive value of each index at different time points on the patient's disease progress. RESULTS: A total of 106 patients were selected, including 89 patients in the stable group and 17 patients in the aggravating group, and the baseline data of the two groups were balanced. CRP, CRP/PA increased and PA decreased in brain trauma patients 6 hours after injury, and reached the peak value or valley value at 48 hours. Compared with the stable group, CRP/PA significantly increased at 24, 48 and 72 hours in the aggravating group [24 hours: 34.18 (20.19, 67.10) vs. 13.98 (4.36, 38.30), 48 hours: 71.10 (45.55, 96.97) vs. 16.02 (5.05, 41.76), 72 hours: 23.25 (4.46, 38.61) vs. 4.72 (2.38, 12.95), all P < 0.05]. ROC curve analysis showed that CRP/PA ratio at 24 hours and 48 hours after injury could be used as a predictor of disease progression. The area under the ROC curve (AUC) of 24 hours CRP/PA was 0.71, 95% confidence interval (95%CI) was 0.58-0.84, the cut-off value was 28.29, the sensitivity was 76.5%, and the specificity was 73.0%. The AUC of 48 hours CRP/PA was 0.76, 95%CI was 0.62-0.90, and the cut-off value was 37.18, the sensitivity was 88.2%, and the specificity was 70.8%. CONCLUSIONS: The dynamic monitoring of CRP/PA ratio in adult after traumatic brain injury can evaluate the disease condition, and the CRP/PA ratio of 24 hours and 48 hours can predict the progress of the disease.

[Design and implementation of an integrated information platform for emergency interconnection].

OBJECTIVE: To establish a "patient-centered" integrated information platform for emergency interconnection. METHODS: Based on the existing software, hardware and network systems of the hospital, design ideas of the modularization, process and standardized were used to reshape the process of emergency diagnosis and treatment in department of emergency-critical care medicine of Huashan North Hospital, Fudan University, and develop integrated information platform for emergency interconnection, including triage, emergency physician workstation, electronic medical records, clinical pathways of key diseases, medical integration, electronic handover classes, imaging, testing, ultrasound, drug counseling and medication safety, performance appraisal and management systems of scientific research, etc. RESULTS: The information platform for emergency interconnection was successfully developed. The functional logic of each system was clear and concise. It had strong compatibility, stable performance and powerful processing capability. It could quickly query the target content and support free and fast switching of each window. At present, daily diagnosis and treatment of emergency patients were realized by informationization, which completely liberated the manual labor of medical staff, shortened the processing time of unit patient, and significantly improved efficiency of the work. At the peak of the patients' visit, the overall operation of the emergency department was stable, and all the work was carried out in an orderly manner. There was no delay of the diagnosis and treatment for critically ill patients in the emergency department. Emergency access to patients with key diseases was smooth, and waiting time was significantly shortened. Clinical decision-making of medical staff had been effectively regulated. The success rates of the patients with acute trauma or acute respiratory failure were significantly improved, the time of the critical treatment were significantly shortened in patients with emergency respiratory cardiac arrest or acute ST-segment elevation myocardial, and compliance rate of the door-to-balloon time met the requirements of the Emergency Room to Balloon Expansion Time (DTB) Alliance. CONCLUSIONS: The integrated information platform for emergency interconnection ran through the whole process of emergency diagnosis and treatment, based on emergency clinical practice, which could meet the needs of daily work in emergency department and help improve the quality of emergency medical and department management.

Poly(lactide-co-glycolide)/Hydroxyapatite Porous Scaffold with Microchannels for Bone Regeneration.

Mass transfer restrictions of scaffolds are currently hindering the development of three-dimensional (3D), clinically viable, and tissue-engineered constructs. For this situation, a 3D poly(lactide-co-glycolide)/hydroxyapatite porous scaffold, which was very favorable for the transfer of nutrients to and waste products from the cells in the pores, was developed in this study. The 3D scaffold had an innovative structure, including macropores with diameters of 300⁻450 µm for cell ingrowth and microchannels with diameters of 2⁻4 µm for nutrition and waste exchange. The mechanical strength in wet state was strong enough to offer structural support. The typical structure was more beneficial for the attachment, proliferation, and differentiation of rabbit bone marrow mesenchymal stem cells (rBMSCs). The alkaline phosphatase (ALP) activity and calcium (Ca) deposition were evaluated on the differentiation of rBMSCs, and the results indicated that the microchannel structure was very favorable for differentiating rBMSCs into maturing osteoblasts. For repairing rabbit radius defects in vivo, there was rapid healing in the defects treated with the 3D porous scaffold with microchannels, where the bridging by a large bony callus was observed at 12 weeks post-surgery. Based on the results, the 3D porous scaffold with microchannels was a promising candidate for bone defect repair.

S-osteotomy with lengthening and then nailing compared with traditional Ilizarov method.

PURPOSE: The purpose of this study was to explore the clinical effect of the novel method combined longitudinal S-osteotomy and Lengthen And Then Nail (LATN) technique for leg lengthening and compare with the classic Ilizarov method. METHODS: This retrospective study was performed from March 2008 to April 2012. A total of 176 leg lengthenings (88 consecutive patients) were performed at our institution. The mean duration of follow-up was 2.2 years (range, one to four years). In group A, 78 tibial lengthenings were performed with longitudinal S-osteotomy and LATN technique. In group B, 98 tibial lengthenings were performed with the classic method. The final gain in length, mean surgical time for bilateral tibial osteotomy, the external fixation index and the radiographic consolidation index were calculated and compared. The complications encountered during operation and follow-up were documented. RESULTS: There was no significant difference in the final gain in length between the two groups. Mean surgical time in group A (130.05 ± 6.60 min) was significantly longer than that in group B (91.4 ± 6.61 min; P < 0.05). External fixation index in group A (21.02 ± 3.16 days/cm) was significantly lower than that in group B (76.19 ± 8.32 days/cm; P < 0.05). Consolidation index was significantly lower (more rapid healing) in group A (43.38 ± 5.35 days/cm) than that in group B (76.19 ± 8.32 days/cm; P < 0.05). There was a significant difference in pin-tract problems and axial deviation between the two groups. CONCLUSION: The novel method combined longitudinal S-corticotomy and LATN technique safely reduces the consolidation time, rate of pin-tract problems and axial deviation during leg lengthening, compared with the classic Ilizarov method.

Comparative study of perpendicular versus parallel double plating methods for type C distal humeral fractures.

BACKGROUND: Double plate osteosynthesis is the standard treatment for intra-articular fractures of the distal humerus. However, there is still controversy concerning dual plate positions in terms of providing optimal stability. The purpose of this retrospective study was to compare the clinical outcomes in patients with type C intra-articular distal humeral fractures using perpendicular and parallel plating methods. METHODS: Between March 2008 and June 2011, a total of 45 patients with type C distal humerus fractures were treated using two different dual plating methods. Of them, 24 patients were treated by perpendicular plating (group I) and 21 patients were treated by parallel plating (group II). The surgical time, blood loss, and union time were compared between the two groups. The flexion-extension arc, the total range of flexion and extension at the end of follow-up were compared between the two groups. The Mayo Elbow Performance Score (MEPS) was used to determine the elbow functional results. RESULTS: All patients were followed up. The mean duration of follow-up was 16 months (range 12 - 25 months) in group I and 15.5 months in group II (range 12 - 25 months). There were no significant differences in the surgical time, blood loss, and the bone union time between the two groups. In group I, the mean elbow flexion-extension arc was 101° and the mean MEPS was 85 points. The rate of excellent and good results was 87.5%. In group II, the mean flexion-extension arc was 100° and the mean MEPS was 86.1 points. The rate of excellent and good results was 90.5%. There were no significant differences in the MEPS, flexion-extension arc, and the total range of flexion and extension between the two groups. CONCLUSIONS: Perpendicular and parallel plate configurations with the appropriate surgical techniques can provide anatomical reconstruction and stable fixation of type C intra-articular distal humeral fractures and allow early mobilization of the elbow after an operation. The occurrence of post-operative elbow stiffness can be reduced and good outcomes can be obtained.