[Real-time traking and virtual reality technology-assisted trauma orthopaedic surgery robot for femoral neck fractures].

OBJECTIVE: To investigate the effectiveness of real-time tracking and virtual reality technology（RTVI） used to assist the intraoperative alignment of the trauma orthopaedic surgery robot for the treatment of femoral neck fractures and its impact on the treatment outcome. METHODS: A retrospective analysis was conducted on 60 patients with femoral neck fractures treated with trauma orthopedic robotic surgery from September 2020 to September 2022. Patients were divided into two groups according to whether RTVI technology was used during surgery to assist robotic surgery. There were 28 patients in the RTVI group （12 males and 16 females）, with an average age of （46.2±9.3） years old ranging from 28 to 60 years old. There were 32 patients in the simple Tianji surgical robot group, including 15 males and 17 females, aged （48.2±7.8） years old ranging from 32 to 58. The number of registered fluoroscopy, operation time, total number of intraoperative fluoroscopy, intraoperative blood loss, and hospitalization time of the two groups of patients were observed and recorded. All patients received regular follow-up after surgery, and hip X-rays were routinely reviewed to record Garden alignment index, fracture healing time, postoperative complications, and Harris score. RESULTS: All 60 patients were followed up. The RTVI group was followed up for 9 to 16 months with an average of （13.0±1.2） months, and the Tianji surgical robot group alone was followed up for 10 to 14 months with an average of （12.0±1.3） months. During the follow-up period, the femoral neck fractures of both groups of patients healed well, and no complications such as internal fixation loosening and incision infection occurred. The number of registered fluoroscopy, operation time, and number of intraoperative fluoroscopy of patients in the RTVI group were significantly better than those in the simple Tianji surgical robot group（P<0.01）. There was no statistically significant difference in intraoperative blood loss, hospital stay, Garden alignment index, fracture healing time, and hip Harris score between two groups（P>0.05）. CONCLUSION: Although RTVI technology assisted by the surgical robot for femoral neck fracture surgery has little impact on its postoperative outcome, it can effectively reduce the operating time, the number of intraoperative X-ray projections, and the risk of intraoperative radiation exposure to patients. It also shortened the learning curve of the operator and better reflected the precision and efficiency of the trauma orthopaedic surgery robot.

Biomechanical insights into ankle instability: a finite element analysis of posterior malleolus fractures.

BACKGROUND: Posterior malleolus fractures are known to be associated with ankle instability. The complexities involved in obtaining precise laboratory-based spatial pressure measurements of the ankle highlight the significance of exploring the biomechanical implications of these fractures. METHODS: Finite element analysis was utilized to examine the stress distribution across the contact surface of the ankle joint, both in its natural state and under varied sagittal fracture line angles. The study aimed to identify stress concentration zones and understand the influence of sagittal angles on stress distribution. RESULTS: Three distinct stress concentration zones were identified on the ankle's contact surface: the anterolateral tibia, the anteromedial tibia, and the fracture line. The most significant stress was observed at the fracture line when a fracture occurs. Stress at the fracture line notably spikes as the sagittal angle decreases, which can potentially compromise ankle stability. Larger sagittal angles exhibited only minor stress variations at the contact surface's three vertices. It was inferred that sagittal angles below 60° might pose risks to ankle stability. CONCLUSIONS: The research underscores the potential implications of fractures on the stress profile of the ankle joint, emphasizing the role of the contact surface in ensuring stability. The identification of three zones of stress concentration and the influence of sagittal angles on stress distribution offers a valuable reference for therapeutic decision-making. Further, the study reinforces the importance of evaluating sagittal fracture angles, suggesting that angles below 60° may compromise ankle stability.

A novel anatomical self-locking plate fixation for both-column acetabular fractures.

PURPOSE: To compare the stability of the posterior anatomic self-locking plate (PASP) with two types of popular reconstruction plate fixation, i.e. double reconstruction plate (DRP) and cross reconstruction plate (CRP), and to explore the influence of sitting and turning right/left on implants. METHODS: PASP, DRP and CRP were assembled on a finite element model of both-column fractures of the left acetabulum. A load of 600 N and a torque of 8 N·m were loaded on the S1 vertebral body to detect the change of stress and displacement when sitting and turning right/left. RESULTS: The peak stress and displacement of the three kinds of fixation methods under all loading conditions were CRP > DRP > PASP. The peak stress and displacement of PASP are 313.5 MPa and 1.15 mm respectively when turning right; and the minimal was 234.0 Mpa and 0.619 mm when turning left. CONCLUSION: PASP can provide higher stability than DRP and CRP for both-column acetabular fractures. The rational movement after posterior DRP and PASP fixation for acetabular fracture is to turn to the ipsilateral side, which can avoid implant failure.

ACY­1215, a HDAC6 inhibitor, decreases the dexamethasone­induced suppression of osteogenesis in MC3T3­E1 cells.

Glucocorticoid­induced osteoporosis is the commonest form of drug­induced osteoporosis. Histone deacetylase 6 (HDAC6) is involved in the differentiation from mesenchymal stem cells to osteoblasts. However, the role of ricolinostat (ACY­1215, HDAC6 inhibitor) in the dexamethasone (Dex)­induced proliferation and differentiation of preosteoblasts remains to be elucidated. The protein expression and mRNA expression levels of HDAC6, osteopontin (OPN), runt­related transcription factor 2 (Runx2), osterix (Osx), collagen I (COL1A1) and glucocorticoid receptor (GR) in MC3T3­E1 cells were analyzed by western blot analysis and reverse transcription­quantitative PCR analysis. The cell viability was detected by CCK­8 assay. The alkaline phosphatase (ALP) activity and capacity of mineralization was determined by ALP assay kit and alizarin red staining. HDAC6 expression was increased in patient serum and Dex­induced MC3T3­E1 cells at a certain concentration range; 1 µM Dex was selected for further experimentation. Cell viability was decreased after Dex induction and restored following ACY­1215 treatment. The ALP activity and capability for mineralization was decreased when MC3T3­E1 cells were induced by 1 µM Dex and was gradually improved by the treatment of ACY­1215 at 1, 5 and 10 mM. The expression of OPN, Runx2, Osx and COL1A1 was similar, with the changes of capability for mineralization. Furthermore, GR expression was increased in Dex­induced MC3T3­E1 cells. ACY­1215 promoted the GR expression in MC3T3­E1 cells from 1­5 mM while GR receptor expression was increased with 10 mM ACY­1215 treatment. In conclusion, ACY­1215 reversed the Dex­induced suppression of proliferation and differentiation of MC3T3­E1 cells.

Autograft or Allograft? Irradiated or Not? A Contrast Between Autograft and Allograft in Anterior Cruciate Ligament Reconstruction: A Meta-analysis.

PURPOSE: To compare the clinical outcomes and adverse events associated with irradiated and nonirradiated allografts in anterior cruciate ligament (ACL) reconstruction. METHODS: PubMed, Web of Science, and EMBASE were searched for randomized controlled trials from January 1990 to March 2018 to compare autograft with allograft in ACL reconstruction. Both objective and subjective outcomes of the function and adverse events were meta-analyzed. Two comparisons were summarized: (1) autograft and nonirradiated allograft and (2) autograft and irradiated allograft. The bias risk was based on the Cochrane Handbook for Systematic Reviews of Interventions. The overall risk ratio or weighted mean difference was calculated using a fixed- or random-effects model. Heterogeneity between studies was evaluated by the Q and the I2 statistics. RESULTS: Eleven trials were included in this review for meta-analysis. A total of 1,172 patients were involved (465 autograft and 461 nonirradiated allograft; 141 autograft and 138 irradiated allograft patients). The average follow-up varied from 2 to >10 years. The mean patient age varied from 22 to 32.8 years. The total failure rate was 2.5%. Our analyses demonstrated better clinical outcomes in autograft than irradiated allograft, which could be observed clearly through the International Knee Documentation Committee score (3.84; 95% confidence interval [CI], 1.93-5.76; P < .0001; I2 = 0%), Lysholm score (2.94; 95% CI, 0.66-5.22; P = .01; I2 = 0%), and Tegner score (0.14; 95% CI, -0.08 to 0.36; P = .22; I2 = 0%) with fewer adverse events 0.20 (95% CI, 0.11-0.39; P < .00001; I2 = 0%). There were no significant differences in autograft and nonirradiated allograft groups (P = .47, P = .27, P = .24, and P = .24, respectively). CONCLUSIONS: Autograft offered greater advantages in functional outcomes and adverse events than irradiated allograft in ACL reconstruction; however, there were no significant differences between autograft and nonirradiated allograft in ACL reconstruction. LEVEL OF EVIDENCE: Level II, meta-analysis of Level I and Level II studies.