Objective:To evaluate the feasibility and efficacy of our self-designed intelligent robot-assisted reduction system for fresh subtrochanteric fractures of the femur.Methods:A retrospective cohort study was conducted to include 10 patients with fresh subtrochanteric fracture of the femur who had been admitted to Department of Orthopedic Trauma, Beijing Jishuitan Hospital from January 2024 to July 2024. There were 7 males and 3 females with an age of (45.0±14.3) years and an interval from injury to surgery of (7.9±3.7) d. All the patients were treated by minimally invasive reduction which was assisted by our self-designed intelligent robot, and internal fixation with intramedullary nails. The operation duration, intraoperative reduction duration, intraoperative blood loss, and intraoperative fluoroscopy frequency were recorded. The reduction effect was evaluated by calculating the differences between preoperative planning and postoperative CT reconstruction (i.e., the differences in femoral shaft length and in rotation angle). The hip functional recovery was assessed by Harris hip function Scoring.Results:The mean operation time was 200.0 (161.3, 217.5) min, the reduction time (83.0±35.5) min, the intraoperative blood loss (290.0±110.1) mL, and the intraoperative fluoroscopy 18.5 (9.0, 19.3) times. In all patients, the difference in femoral shaft length was (2.4±1.4) mm, and the difference in rotation angle 5.1°±3.0°. All patients were followed up for (8.2±2.0)months. All the fractures got united at the last follow-up. Their Harris hip function score was (83.3±4.1) points.Conclusion:Our self-designed intelligent robot-assisted reduction system is feasible and effective in the surgery of fresh subtrochanteric fracture of the femur, because the robot system can complete the autonomous planning of reduction approaches before surgery and assist fracture reduction under real-time monitoring with three-dimensional images, leading to fine outcomes.

This review aimed to provide a comprehensive analysis of the etiology, epidemiology, pathology, and conventional treatment of heterotopic ossification (HO), especially emerging potential therapies. HO is the process of ectopic bone formation at non-skeletal sites. HO can be subdivided into two major forms, acquired and hereditary, with acquired HO predominating. Hereditary HO is a rare and life-threatening genetic disorder, but both acquired and hereditary form can cause severe complications, such as peripheral nerve entrapment, pressure ulcers, and disability if joint ankylosis develops, which heavily contributes to a reduced quality of life. Modalities have been proposed to treat HO, but none have emerged as the gold standard. Surgical excision remains the only effective modality; however, the optimal timing is controversial and may cause HO recurrence. Recently, potential therapeutic strategies have emerged that focus on the signaling pathways involved in HO, and small molecule inhibitors have been shown to be promising. Moreover, additional specific targets, such as small interfering RNAs (siRNAs) and non-coding RNAs, could be used to effectively block HO or develop combinatorial therapies for HO.
Humans ; Ossification, Heterotopic/genetics*

To compare gait parameters during single-task and dual-task walking in older adults, and to examine differences in dual-task costs between individuals with high versus low balance abilities under different task conditions.

Objective:To evaluate the feasibility and efficacy of our self-designed intelligent robot-assisted reduction system for fresh subtrochanteric fractures of the femur.Methods:A retrospective cohort study was conducted to include 10 patients with fresh subtrochanteric fracture of the femur who had been admitted to Department of Orthopedic Trauma, Beijing Jishuitan Hospital from January 2024 to July 2024. There were 7 males and 3 females with an age of (45.0±14.3) years and an interval from injury to surgery of (7.9±3.7) d. All the patients were treated by minimally invasive reduction which was assisted by our self-designed intelligent robot, and internal fixation with intramedullary nails. The operation duration, intraoperative reduction duration, intraoperative blood loss, and intraoperative fluoroscopy frequency were recorded. The reduction effect was evaluated by calculating the differences between preoperative planning and postoperative CT reconstruction (i.e., the differences in femoral shaft length and in rotation angle). The hip functional recovery was assessed by Harris hip function Scoring.Results:The mean operation time was 200.0 (161.3, 217.5) min, the reduction time (83.0±35.5) min, the intraoperative blood loss (290.0±110.1) mL, and the intraoperative fluoroscopy 18.5 (9.0, 19.3) times. In all patients, the difference in femoral shaft length was (2.4±1.4) mm, and the difference in rotation angle 5.1°±3.0°. All patients were followed up for (8.2±2.0)months. All the fractures got united at the last follow-up. Their Harris hip function score was (83.3±4.1) points.Conclusion:Our self-designed intelligent robot-assisted reduction system is feasible and effective in the surgery of fresh subtrochanteric fracture of the femur, because the robot system can complete the autonomous planning of reduction approaches before surgery and assist fracture reduction under real-time monitoring with three-dimensional images, leading to fine outcomes.

Objective:To explore the clinical efficacy of operative treatment of geriatric pelvic fractures.Methods:A retrospective study was conducted to analyze the clinical data of 55 geriatric patients with pelvic fracture who had been operatively treated at Department of Orthopaedic Trauma, Beijing Jishuitan Hospital from January 2020 to October 2023. There were 13 males and 42 females with an age of 72.0 (68.0, 83.3) years. By the AO/OTA classification, there were 47 cases of type B and 8 cases of type C; by the classification for fragility fractures of pelvis, there were 5 cases of type Ⅱ, 44 cases of type Ⅲ, and 6 cases of type Ⅳ. The patients received operative treatment 4.0 (3.0, 6.3) days after injury. Of the 10 patients treated by open reduction and closed reduction, the posterior ring was fixated by a plate in 7 and by screws in 3, and the anterior ring was fixated by either a plate, an external fixator or a minimally invasive anterior pelvic ring internal fixator except in the 2 cases receiving no fixation. Of the other 45 patients treated by closed reduction and fixation, the posterior ring was all fixated by screws except in the 2 cases receiving no fixation, and the anterior ring was fixated by either screws, an external fixator or a minimally invasive anterior pelvic ring internal fixator except in the 10 cases receiving no fixation. The major peri-operative complications, quality of fracture reduction, mortality, and functional recovery of the pelvis at the last follow-up were recorded.Results:There were no major peri-operative complications. According to the Matta criteria, the quality of fracture reduction was excellent in 31, good in 14, fair in 8 and poor in 2 cases, giving a good to excellent rate of 81.8% (45/55). Fifty-four cases were followed up for (15.4±9.1) months and 1 case was lost to the follow-up. Four cases died within 1 year after operation, giving a mortality of 7.4% (4/54). The modified Majeed score at the last follow-up was 69 (54, 76) for the 46 cases who had been followed up for longer than 4 months; the functional recovery of the pelvis at the last follow-up was rated as excellent in 27 cases, as good in 8 cases and as fair in 11 cases, giving a good to excellent rate of 76.1% (35/46) according to the criteria proposed by the faculty of the writers. The internal fixation failed in 3 cases during the follow-up.Conclusion:For the geriatric pelvic fractures, operative treatment can lead to satisfactory clinical outcomes.

BACKGROUND:Scaffold materials serve as platforms that provide space and structure,playing a crucial role in the regeneration of cartilage tissue.Scholars from around the world are exploring different approaches to fabricate more ideal scaffold materials. OBJECTIVE:To review the design principles and preparation methods of cartilage scaffolds,and to further explore the advantages and limitations of various preparation methods. METHODS:Literature searches were conducted on the databases of CNKI,WanFang Data,PubMed,and FMRS from 1998 to 2023.The search terms were"cartilage repair,cartilage tissue engineering,cartilage scaffold materials,preparation"in Chinese and English.A total of 57 articles were ultimately reviewed. RESULTS AND CONCLUSION:(1)The articular cartilage has a unique structure and limited self-repair capacity after injury.Even if self-repair occurs,the newly formed cartilage is typically fibrocartilage,which is far inferior to normal articular cartilage in terms of structure and mechanical properties.It is difficult to maintain normal function and often leads to degenerative changes.Currently,the design and fabrication of scaffold materials for cartilage repair need to consider the following aspects:biocompatibility and biodegradability,suitable pore structure and porosity,appropriate mechanical properties,and bioactivity.(2)Research on the preparation of cartilage scaffolds has made significant progress,continuously introducing new preparation methods and optimization strategies.These methods have their advantages and disadvantages,providing more possibilities for customized preparation and functional design of cartilage scaffolds according to specific requirements.

BACKGROUND:Bone formation is the process by which osteoblasts synthesize and secrete osteoid and promote its mineralization,which generally involves mechanical signal transduction.Osteoblasts are primarily regulated by mechanical factors such as gravity,compressive stress,tensile stress,fluid shear stress,and hydrostatic pressure in vivo,and different mechanical stimuli modulate the proliferation,differentiation,and apoptosis of osteoblasts through various mechanisms,including hormones,cytoskeletal proteins,and microRNAs.By clarifying the effects of biomechanical forces on osteoblasts,it provides ideas and a reference basis for the treatment of osteometabolic diseases involving osteoblasts. OBJECTIVE:To review the effects of different biomechanical forces on the biological characteristics of osteoblasts. METHODS:We conducted a literature search using PubMed,Web of Science,FMRS,CNKI,and WanFang databases for relevant publications published from 2000 to 2023,covering basic research and tissue engineering studies related to the effects of biomechanical forces on osteoblasts.Ultimately,a total of 70 articles were reviewed. RESULTS AND CONCLUSION:Different biomechanical forces have an impact on the biological characteristics of osteoblasts,including proliferation,differentiation,and apoptosis,and these effects are dependent on the intensity and duration of the applied force.Specifically,the effects are as follows:(1)Under microgravity conditions,osteoblast proliferation and differentiation are inhibited,resulting in a decrease in bone density and the development of osteoporosis.(2)Compared to microgravity,hypergravity has a promoting effect on osteoblast proliferation.(3)The effects of compressive stress on osteoblasts are dependent on the loading intensity and time.Appropriate compressive stress can promote osteoblast proliferation and differentiation,which is beneficial for bone tissue formation and repair,while excessive compressive stress can cause osteoblast apoptosis and bone tissue destruction.(4)The biological effects of different types of tensile stress on osteoblasts differ.Studies have shown that a strain rate within the range of 0-12%has a promoting effect on osteoblast proliferation.(5)Fluid shear stress can promote osteoblast proliferation and differentiation and enhance the bone-inducing effect of biomaterials.(6)Static hydrostatic pressure can affect the biological behavior of osteoblasts,including proliferation,differentiation,and apoptosis,and these effects are closely related to the time and intensity of the pressure.Understanding the effects of different biomechanical forces on osteoblasts is of great significance for a deeper understanding of bone growth and maintenance mechanisms.

Objective:To assess the rationality of the maximum lesion diameter of 15 mm in prostate imaging reporting and data system(PI-RADS)as a criterion for upgrading a lesion from category 4 to 5 and improve it to enhance the prediction of clinically significant prostate cancer(csPCa).Methods:In this study,the patients who underwent prostate magnetic resonance imaging(MRI)and prostate biopsy at Peking University First Hospital from 2019 to 2022 as a development cohort,and the patients in 2023 as a validation cohort were reviewed.The localization and maximum diameter of the lesion were fully evalua-ted.The area under the curve(AUC)and the cut-off value of the maximum diameter of the lesion to pre-dict the detection of csPCa were calculated from the receiver operating characteristics(ROC)curve.Confounding factors were reduced by propensity score matching(PSM).Diagnostic efficacy was com-pared in the validation cohort.Results:Of the 589 patients in the development cohort,358(60.8％)lesions were located in the peripheral zone and 231(39.2％)were located in the transition zone,and 496(84.2％)patients detected csPCa.The median diameter of the lesions in the peripheral zone was smaller than that in the transition zone(14 mm vs.19 mm,P＜0.001).In the ROC analysis of the maximal diameter on the csPCa prediction,there was no statistically significant difference between the peri-pheral zone(AUC=0.709)and the transition zone(AUC=0.673,P=0.585),and the cut-off values were calculated to be 11.5 mm for the peripheral zone and 16.5 mm for the migrating zone.By calcula-ting the Youden index for the cut-off values in the validation cohort,we found that the categorisation by lesion location led to better predictive results.Finally,the net reclassification index(NRI)was 0.170.Conclusion:15 mm as a criterion for upgrading the PI-RADS score from 4 to 5 is reasonable but too general.The cut-off value for peripheral zone lesions is smaller than that in transitional zone.In the future consideration could be given to setting separate cut-off values for lesions in different locations.

Objective:To explore the short-term efficacy of fixation with a 3D printed individualized custom-made plate in the treatment of elderly patients with periprosthetic femoral fracture.Methods:Retrospectively analyzed were the 5 elderly patients with periprosthetic femoral fracture who had been treated by fixation with a 3D printed individualized custom-made plate from January 2022 to July 2022 at Department of Orthopaedics and Traumatology, Beijing Jishuitan Hospital. There were 3 males and 2 females, aged 81, 86, 77, 91 and 87 years, respectively. One left and 4 right limbs were affected. Vancouver classification: type B1 ( n=3), type B2 ( n=1), and type C ( n=1). The time from operation to injury was 5, 6, 10, 5 and 7 days, respectively. Preoperatively, the femur affected, prosthesis and individualized plate with a greater trochanteric hook, loop cable channel and bone-like trabecular microporous structure were custom-made by 3D printing according to 1:1 models. Virtual operations were simulated to formulate surgical protocols. The operation time, length of surgical incision, intraoperative blood loss and transfusion, hospital stay, hip function and complications at the last follow-up were recorded. Results:The 5 patients were followed up for 12, 7, 10, 3 and 6 months, respectively. There were no events of superficial incision or deep prosthesis infection. Respectively, the operation time was 1.8, 1.7, 2.3, 2.0 and 3.3 h; the length of surgical incision 31, 30, 38, 27 and 30 cm; the intraoperative bleeding volume 400, 300, 300, 500 and 600 mL; the length of hospital stay 8, 9, 15, 14 and 11 d. Four patients received intraoperative blood transfusion of 300, 900, 150 and 1, 050 mL, respectively. One patient died of a heart attack 3 months after discharge; another patient developed dyskinesia at the contralateral limb 3 months after discharge due to cerebral infarction and died of recurrent cerebral infarction 7 months after discharge. At the last follow-up, the Harris hip scores of 3 patients were 86, 77 and 69 points, respectively. None of the patients had complications like breakage or loosening of implants.Conclusion:In the treatment of elderly patients with periprosthetic femoral fracture, fixation with a 3D printed individualized custom-made plate may lead to fine limb function and good short-term curative efficacy.

Objective:To investigate the early clinical effectiveness of using customized 3D printed acetabular augment to repair large acetabular bone defects in delayed total hip arthroplasty after failed treatment of acetabular fractures.Methods:A retrospective study was conducted to analyze the 6 patients who had undergone 3D printed acetabular augment to reconstruct acetabular bone defects in delayed total hip replacement from July 2021 to January 2023 after failed treatment of acetabular fractures. They were all males, with an age of (51.3±15.0) years. Paprosky classification: 2 cases of type ⅡB, 1 case of type ⅡC, and 3 cases of type ⅢA. Recorded were surgical time, intraoperative bleeding, hospitalization time, and visual analogue scale (VAS), and modified Merle d'Aubigné & Postel score, Harris hip score, and leg length discrepancy at the last follow-up.Results:For the 6 patients, the mean surgical time was (222.5±46.9) min, the mean intraoperative bleeding 1,100 (1,000, 2,625) mL, the mean hospitalization time (9.0±4.5) d, and the mean follow-up time (11.8±7.9) months. At the last follow-up, the VAS [(2.5±1.0) points] significantly decreased compared with the preoperative value [(6.2±0.8) points], the modified Merle d'Aubigné & Postel score [(13.2±2.1) points] and Harris hip score [(67.8±15.3) points] significantly increased compared with the preoperative values [(6.7±0.8) and (34.2±8.4) points], the vertical position of center of rotation [(22.5±5.2) mm] and the horizontal position of center of rotation [(40.7±2.6) mm] were significantly reduced compared with the preoperative values [(38.1±14.2) and (53.1±10.0) mm] ( P<0.05). At the last follow-up, the leg length discrepancy was (6.2±3.6) mm, showing no statistically significant difference from the preoperative value [(18.7±1.7) mm] ( P>0.05). At the last follow-up, no clear line at the cup-bone or augment-bone interface, or no possible prosthetic loosening or displacement was observed on the X-ray films. Conclusion:In delayed total hip arthroplasty after failed treatment of acetabular fractures, the customized 3D printed augment for repair of large bone defects in the acetabulum can reconstruct the normal rotation center of the hip joint, provide reliable stability for the cup prosthesis, and enable patients to obtain significant improvements in hip function.