Perioperative management of acetabular and pelvic fractures: evidence-based recommendations

Preperitoneal pelvic balloon tamponade-an effective intervention to control pelvic injury hemorrhage in a swine model

Objective: This study aimed to estimate the effects of the volume of preperitoneal balloon (PPB) on arterial and venous hemorrhage in a swine pelvic fracture model. Methods: Twenty-four swine were randomized into 0-mL, 500-mL, 800-mL, and 1000-mL intra-hematoma PPB groups. They were subjected to open-book pelvic fracture and reproducible injuries in the external iliac artery and vein. The pelvic binder and IH-PPBs with different volumes of fluid were applied to control the active hemorrhage after arterial and venous injuries. The survival time and rate during 60-min observation and digital subtraction angiography (DSA) images were the primary endpoints in this study. Secondary endpoints included survival rate within 70 min, peritoneal pressure, hemodynamics, blood loss, infusion fluid, blood pH, and lactate concentration. Results: Our results indicated that the 800-mL and 1000-mL groups had a higher survival rate (0%, 50%, 100% and 100% for 0, 500, 800, and 1000-mL groups respectively; p < 0.0001) and longer survival time (13.83 ± 2.64, 24.50 ± 6.29, 55.00 ± 6.33, and 60.00 ± 0.00 min for 0, 500, 800, and 1,000 groups respectively; p < 0.0005) than the 0-mL or 500-mL groups during the 60 min observation. Contrastingly, survival rate and time were comparable between 800-mL and 1000-mL groups during the 60-min observation. The IH-PPB volume was associated with an increase in the pressure of the balloon and the preperitoneal pressure but had no effect on the bladder pressure. Lastly, the 1000-mL group had a higher mean arterial pressure and systemic vascular resistance than the 800-mL group. Conclusion: IH-PPB volume-dependently controls vascular bleeding after pelvic fracture in the swine model. IH-PPB with a volume of 800 mL and 1000 mL efficiently managed pelvic fracture-associated arterial and venous hemorrhage and enhanced survival time and rate in the swine model without evidences of visceral injury.

Interaction of preoperative chemoprophylaxis and tranexamic acid use does not affect transfusion in acetabular fracture surgery

PURPOSE

While the effects of tranexamic acid (TXA) use on transfusion rates after acetabular fracture surgery are unclear, previous evidence suggests that holding deep vein thrombosis (DVT) chemoprophylaxis may improve TXA efficacy. This study examines whether holding DVT chemoprophylaxis in patients receiving TXA affects intraoperative and postoperative transfusion rates in acetabular fracture surgery.

METHODS

We reviewed electronic medical records (EMR) of 305 patients who underwent open reduction and internal fixation of acetabular fractures (AO/OTA 62) and stratified patients per the following perioperative treatment: (1) no intraoperative TXA (noTXA), (2) intraoperative TXA and no preoperative DVT prophylaxis (opTXA/noDVTP), or (3) intraoperative TXA and preoperative DVT prophylaxis (opTXA/opDVTP). The primary outcomes were need for intraoperative or postoperative transfusion. Risk factors for each primary outcome were assessed using multivariable regression.

RESULTS

Intraoperative or postoperative transfusion rates did not significantly differ between opTXA/opDVTP and opTXA/noDVTP groups (46.2% vs. 36%, p = 0.463; 15.4% vs. 28%, p = 0.181). Median units transfused did not differ between groups (2 ± 1 vs. 2 ± 1, p = 0.515; 2 ± 1 vs. 2 ± 0, p = 0.099). There was no association between preoperative DVT chemoprophylaxis and TXA with intraoperative or postoperative transfusions. EBL, preoperative hematocrit, and IV fluids were associated with intraoperative transfusions; age and Charlson Comorbidity Index (CCI) were associated with postoperative transfusions.

CONCLUSION

Our findings suggest holding DVT prophylaxis did not alter the effect of TXA on blood loss or need for transfusion.

The application of inferior vena cava filters in orthopaedics and current research advances

Deep vein thrombosis is a common clinical peripheral vascular disease that occurs frequently in orthopaedic patients and may lead to pulmonary embolism (PE) if the thrombus is dislodged. pulmonary embolism can be prevented by placing an inferior vena cava filter (IVCF) to intercept the dislodged thrombus. Thus, IVCFs play an important role in orthopaedics. However, the occurrence of complications after inferior vena cava filter placement, particularly recurrent thromboembolism, makes it necessary to carefully assess the risk-benefit of filter placement. There is no accepted statement as to whether IVCF should be placed in orthopaedic patients. Based on the problems currently displayed in the use of IVCFs, an ideal IVCF is proposed that does not affect the vessel wall and haemodynamics and intercepts thrombi well. The biodegradable filters that currently exist come close to the description of an ideal filter that can reduce the occurrence of various complications. Currently available biodegradable IVCFs consist of various organic polymeric materials. Biodegradable metals have shown good performance in making biodegradable IVCFs. However, among the available experimental studies on degradable filters, there are no experimental studies on filters made of degradable metals. This article reviews the use of IVCFs in orthopaedics, the current status of filters and the progress of research into biodegradable vena cava filters and suggests possible future developments based on the published literature by an electronic search of PubMed and Medline databases for articles related to IVCFs searchable by October 2022 and a manual search for citations to relevant studies.

Biomechanical evaluation of seven fixation methods to treat pubic symphysis diastasis using finite element analysis

Background

Pubic symphysis diastasis (PSD) hinders the connection between bilateral ischia and pubic bones, resulting in instability of the anterior pelvic ring. PSD exceeding 25 mm is considered disruptions of the symphyseal and unilateral/bilateral anterior sacroiliac ligaments and require surgical intervention. The correct choice of fixation devices is of great significance to treat PSD. This study aimed to evaluate the construct stability and implant performance of seven fixation methods to treat PSD using finite element analysis.

Methods

The intact skeleton-ligament pelvic models were set as the control group. PSD models were simulated by removing relevant ligaments. To enhance the stability of the posterior pelvic ring, a cannulated screw was applied in the PSD models. Next, seven anterior fixation devices were installed on the PSD models according to standard surgical procedures, including single plates (single-Plate group), single plates with trans-symphyseal cross-screws (single-crsPlate group), dual plates (dual-Plate group), single cannulated screws, dual crossed cannulated screws (dual-canScrew group), subcutaneous plates (sub-Plate group), and subcutaneous pedicle screw-rod devices (sub-PedRod group). Compression and torsion were applied to all models. The construct stiffness, symphyseal relative micromotions, and von Mises stress performance were recorded and analyzed.

Results

The construct stiffness decreased dramatically under PSD conditions. The dual-canScrew (154.3 ± 9.3 N/mm), sub-Plate (147.1 ± 10.2 N/mm), and sub-PedRod (133.8 ± 8.0 N/mm) groups showed better ability to restore intact stability than the other groups (p < 0.05). Regarding regional stability, only single-plate fixation provided unexpected regional stability with a diastasis of 2.1 ± 0.2 mm (p < 0.001) under a compressive load. Under a rotational load, the single-crsPlate group provided better regional angular stability (0.31° ± 0.03°, p < 0.001). Stress concentrations occurred in the single-Plate, sub-Plate, and sub-PedRod groups. The maximum von Mises stress was observed in the single-plate group (1112.1 ± 112.7 MPa, p < 0.001).

Conclusion

The dual-canScrew fixation device offers ideal outcomes to maintain stability and prevent failure biomechanically. The single-crsPlate and dual-Plate methods effectively improved single-Plate device to enhance regional stability and disperse stresses. The subcutaneous fixation devices provided both anterior pelvic ring stability and pubic symphysis strength.