Objective: To evaluate the short-term effectiveness of arthroscopic surgery combined with direct anterior approach for hip diseases. Methods: A retrospective study was performed on 23 cases with hip diseases (23 hips), who were treated with the arthroscopic surgery combined with direct anterior approach, between January 2015 and December 2016. There were 9 males and 14 females, aged from 27 to 49 years (mean, 38.6 years). There were 11 cases of posterior dislocation of the hip associated with femoral head fracture (Pipkin typeⅠ) and 7 cases of femoral neck fracture (Garden type Ⅳ). And the interval between injury and operation was 2-8 days (mean, 4.3 days). Five cases were osteonecrosis of femoral head at precollapse stage which were rated as stageⅡA according to Association Research Circulation Osseous (ARCO) classification system. The disease duration was 3-8 months (mean, 5.9 months). The preoperative Harris hip score, Oxford Hip Score (OHS), Postel score, and visual analogue scale (VAS) were 57.3±8.2, 11.2±3.6, 3.2±1.5, and 7.2±1.3, respectively. Results: All the wounds healed primarily. Lateral femoral nerve injury occurred in 3 cases. All patients were followed up 8-19 months (mean, 15.6 months). Bone union achieved in all patients after 14-19 weeks (mean, 15.8 weeks) and no secondary osteoarthritis or heterotopic ossification occurred. At last follow-up, the Harris hip score (92.5±5.3), OHS (36.5±5.9), and Postel score (14.2±2.6) were significantly higher than preoperative scores ( t=45.274, P=0.000; t=36.586, P=0.000; t=32.486, P=0.000), and VAS score (1.8±0.9) was significantly lower than preoperative score ( t=21.314, P=0.000). Conclusion: Arthroscopic surgery combined with direct anterior approach for hip diseases can effectively relieve pain, improve hip function, and obtain the satisfactory short-term effectiveness.

Objective:To investigate the associations of articular depression depth (ADD) and tibial plateau widening (TPW) by pre-operative CT measurement with incidence of lateral meniscal tear in patients with Schatzker type Ⅱ tibial plateau fracture.Methods:Included in this retrospective study were 131 patients who had been admitted to Emergency Center of Trauma, The Third Hospital Affiliated to Hebei Medical University from January 2016 to January 2020 for Schatzker type Ⅱtibial plateau fractures. They were 88 males and 51 females, aged from 18 to 60 years (average, 41.5 years), with 74 right and 57 left sides injured. All patients were treated with closed reduction and internal fixation assisted by bidirectional traction. Arthroscopy was used to detect the status of lateral meniscus immediately after closed reduction and internal fixation of the fracture fragments. Furthermore, patients were divided into 2 groups according to the integrity of lateral meniscus: meniscal tear group ( n=70) and tear-free group ( n=61). The 2 groups were compared in terms of age, gender, body mass index(BMI), injury side, time interval from injury to surgery, TPW and ADD. The receiver operating curve (ROC) was drafted to calculate the cut-off values of TPW and ADD in complication of lateral meniscal tear in patients with Schatzker type Ⅱ tibial plateau fracture. Results:The overall incidence of lateral meniscal tear in this cohort was 53.4% (70/131). There was no statistically significant difference in terms of age, gender, injury side, BMI or time interval from injury to surgery between the 2 groups ( P>0.05); TPW and ADD were significantly higher in the meniscal tear group than in the tear-free group ( P<0.05). To predict lateral meniscal tear in patients with Schatzker type Ⅱtibial plateau fracture, the area under ROC was 0.656 (95% CI: 0.562 to 0.750, P=0.002) for TPW and 0.709 (95% CI: 0.619 to 0.800, P<0.001) for ADD, respectively; the cut-off values of TPW and ADD were 4.3 mm and 6.1 mm. Conclusion:TPW and ADD may be effective predictors for prediction of lateral meniscal tear in patients with Schatzker type Ⅱ tibial plateau fracture.

Objective:To study the morphologic features of the fusion site of proximal tibial epiphysis in normal adults and analyze its potential clinical value based on Mimics three-dimensional (3D) reconstruction.Methods:CT images of knee joint of 68 patients without obvious abnormalities of lower limbs were retrospectively analyzed in electronic database of our hospital from June 2020 to June 2021, including 41 males and 27 females. The mean age of the patients was 38.7±8.4 years (range, 25-55 years), and the mean body mass index (BMI) was 25.3±4.0 kg/m 2 (range, 18.75-41.8 kg/m 2). Mimics 3D reconstruction technique was used to reconstruct the 3D model of the proximal tibia and epiphyseal fusion site. The relationship between the surface area of epiphyseal fusion site and age and BMI was studied, and the changes of cortical thickness and density at epiphyseal fusion site were also explored. Results:The fusion site of adult epiphyseal reconstructed by Mimics 3D reconstruction is a complex wavy surface structure in 3D space. The surface area of the epiphyseal fusion site was 2,994.7±645.3 mm 2 (range, 1,704.0-4,650.0 mm 2) obtained by 3-Matic Research 12.0. The fusing area of male epiphysis was 3 269.3±533.9 mm 2 than that of female 2,577.6±578.7 mm 2, the difference was statistically significant ( t=5.06, P<0.001). However, there was no significant correlation between the epiphyseal fusion site surface area and age ( R2=0.02, P=0.268) and BMI ( R2=0.04, P=0.125). Mimics software was used to obtain the CT values of bone cortex at the epiphysis line and the distal end of the epiphysis line at 10 mm and 20 mm levels as 451.059±74.953 Hu, 1,018.412±125.732 Hu and 1,414.162±107.848 Hu, respectively. The thickness of bone cortex was 1.814±0.090 mm, 2.511±0.089 mm and 3.189±0.185 mm at 10 mm and 20 mm layers of epiphysis line and distal epiphysis line, respectively. Conclusion:In this study, Mimics 3D reconstruction technique was used to visualize the fusion site of the proximal tibial epiphysis in normal adults. The epiphyseal fusion site of adult is a undulating plate-like structure, and the cortical bone density of epiphyseal fusion site is low and thin, theoretically, it is easy to fracture under indirect violence.

Objective To learn the present hospital expenditures of medical devices maintenance for improvement recommendations. Methods An investigation was made to the clinical engineering sections of 33 hospitals in 2018, including 11 Beijing hospitals and 22 Zhejiang hospitals. Indicator values of maintenance expenditure were obtained, and the data were subject to descriptive statistics. Results The mean of beds of these hospitals was 1514. 13 ± 710. 99, that of medical devices was 8120. 90 ± 6488. 63, that of original value of these devices was 843 ± 496 million yuan, and that of maintenance cost was 17. 35 ± 11. 92 million yuan. This indicated the cost of service ratio as 2. 02％. Conclusions Training of engineers should be strengthened at the sections, for more in-house maintenance. Informationization should be enhanced for precision maintenance. Multi-channel maintenance model should be introduced to further lower the costs.

Objective:To explore the clinical efficacy of double traction-assisted reduction internal fixation and open reduction internal fixation in treating tibial plateau fractures.Methods:Data of patients with tibial plateau fracture admitted to West China Hospital of Sichuan University from January 2016 to December 2021 were retrospectively analyzed, and patients were divided into two groups according to treatment method: double traction-closed reduction internal fixation group (referred to as double traction group) and open reduction internal fixation group (referred to as open group). The double traction group included 21 patients, with 15 male and 6 female patients, with a mean age of 56.14±9.24 years (range, 45-72 years). Schatzker classification of fractures: 1 type I, 2 type II, 2 type III, 5 type IV, 6 type V, and 5 type VI. The open group included 29 patients, with 20 male and 9 female patients, with a mean age of 58.97±4.84 years (range, 47-70 years). Schatzker classification of fractures: 2 type I, 4 type II, 8 type III, 4 type IV, 5 type V, and 6 type VI. The surgical time, incision length, intraoperative blood loss, length of hospital stays, fracture healing time, postoperative time to full weight bearing, Rasmussen score, Hospital for Special Surgery (HSS) knee score, and complications were compared between the two groups of patients.Results:Both groups were followed up for 24 to 36 months, with an average of 30 months. There were significant differences in the operation time (92.61±6.22 min vs. 47.92±9.53 min), incision length (4.54±0.56 cm vs. 6.26±0.51 cm), and intraoperative blood loss (47.05±9.72 ml vs. 156.82±4.62 ml) between the group treated with closed reduction and double traction and the group treated with open reduction, with statistical significance ( t=18.83, 10.78, 53.24, P<0.001). There were also significant differences in the hospitalization time (5.35±0.41 d vs. 5.84±0.78 d), fracture healing time (3.72±0.74 months vs. 4.22±0.42 months), and time to full weight-bearing after surgery (11.29±1.10 weeks vs. 15.07±1.96 weeks) between the two groups, with statistical significance ( t=2.30, P=0.026; t=3.38, P<0.001; t=7.96, P<0.001). The HSS score at 6 months after surgery in the group treated with closed reduction and double traction was 81.61±2.32 points, which was higher than the score in the group treated with open reduction (77.66±4.01 points), with statistical significance ( t=4.07, P<0.001); at 12 months after surgery, the Rasmussen score in the group treated with closed reduction and double traction was 16.71±1.00 points, which was higher than the score in the group treated with open reduction (13.79±1.42 points), with statistical significance ( t=8.05, P<0.001). There was no fracture malunion or compartment syndrome occurred in both groups. The incidence of complications was 5% (1/21) in the group treated with closed reduction and double traction, and 10% (3/29) in the group treated with open reduction, with statistical significance (χ 2=0.52, P=0.473). Conclusion:The advantages of double traction-assisted reduction and internal fixation for tibial plateau fractures include minimal trauma, minimal bleeding, early mobilization, and shorter fracture healing time. It is a safe and reliable treatment method.