Use of the Reamer/Irrigator/Aspirator Decreases Carotid and Cranial Embolic Events in a Canine Model

In vivo study to assess fat embolism resulting from the Reamer-Irrigator-Aspirator 2 system compared to a novel aspirator-based concept for intramedullary bone graft harvesting

INTRODUCTION

Fat embolism (FE) following intramedullary (IM) reaming can cause severe pulmonary complications and sudden death. Recently, a new harvesting concept was introduced in which a novel aspirator is used first for bone marrow (BM) aspiration and then for subsequent aspiration of morselized endosteal bone during sequential reaming (A + R + A). In contrast to the established Reamer-Irrigator-Aspirator (RIA) 2 system, the new A + R + A concept allows for the evacuation of fatty BM prior to reaming. In this study, we hypothesized that the risk of FE, associated coagulopathic reactions and pulmonary FE would be comparable between the RIA 2 system and the A + R + A concept.

MATERIALS AND METHODS

Intramedullary bone graft was harvested from intact femora of 16 Merino sheep (age: 1-2 years) with either the RIA 2 system (n = 8) or the A + R + A concept (n = 8). Fat intravasation was monitored with the Gurd test, coagulopathic response with D-dimer blood level concentration and pulmonary FE with histological evaluation of the lungs.

RESULTS

The total number and average size of intravasated fat particles was similar between groups (p = 0.13 and p = 0.98, respectively). D-dimer concentration did not significantly increase within 4 h after completion of surgery (RIA 2: p = 0.82; A + R + A: p = 0.23), with an interaction effect similar between groups (p = 0.65). The average lung area covered with fat globules was similar between groups (p = 0.17).

CONCLUSIONS

The use of the RIA 2 system and the novel A + R + A harvesting concept which consists of BM evacuation followed by sequential IM reaming and aspiration of endosteal bone, resulted in only minor fat intravasation, coagulopathic reactions and pulmonary FE, with no significant differences between the groups. Our results, therefore, suggest that both the RIA 2 system and the new A + R + A concept are comparable technologies in terms of FE-related complications.

Femoral Nailing in a Porcine Model Causes Bone Marrow Emboli in the Lungs and Systemic Emboli in the Heart and Brain

Background

Shaft fractures of the femur are commonly treated with intramedullary nailing, which can release bone marrow emboli into the bloodstream. Emboli can travel to the lungs, impairing gas exchange and causing inflammation. Occasionally, emboli traverse from the pulmonary to the systemic circulation, hindering perfusion and resulting in injuries such as heart and brain infarctions, known as fat embolism syndrome. We studied the extent of systemic bone marrow embolization in a pig model.

Methods

Twelve anesthetized pigs underwent bilateral intramedullary nailing of the femur, while 3 animals served as sham controls. Monitoring included transesophageal echocardiography (TEE), pulse oximetry, electrocardiography, arterial blood pressure measurement, and blood gas and troponin-I analysis. After surgery, animals were monitored for 240 minutes before euthanasia. Post mortem, the heart, lungs, and brain were biopsied.

Results

Bone marrow emboli were found in the heart and lungs of all 12 of the pigs that underwent intramedullary nailing and in the brains of 11 of them. No emboli were found in the sham group. The pigs subjected to intramedullary nailing exhibited significant hypoxia (PaO2/FiO2 ratio, 410 mm Hg [95% confidence interval (CI), 310 to 510) compared with the sham group (594 mm Hg [95% CI, 528 to 660]). The nailing group exhibited ST-segment alterations consistent with myocardial ischemia and a significant increase in the troponin-I level compared with the sham group (1,580 ng/L [95% CI, 0 to 3,456] versus 241 ng/L [95% CI, 0 to 625] at the 240-minute time point; p = 0.005). TEE detected emboli in the right ventricular outflow tract, but not systemically, in the nailing group.

Conclusions

Bilateral intramedullary nailing caused bone marrow emboli in the lungs and systemic emboli in the heart and brain in this pig model. The observed clinical manifestations were consistent with coronary and pulmonary emboli. TEE detected pulmonary but not systemic embolization.

Clinical Relevance

Femoral intramedullary nailing in humans is likely to result in embolization as described in our pig model. Focused monitoring is necessary for detection of fat embolism syndrome. Absence of visual emboli in the left ventricle on TEE does not exclude the occurrence of systemic bone marrow emboli.

Emergency Medicine with Advanced Surgery Protocols: A Review

One of the most burning issues in health system is the concern of handling patients that requires emergency surgery. Emergency general surgery is done on both traumatic and nontraumatic acute disorders. Severe traumatic injury and bleeding is one of the causing agents for high mortality rate globally. Another group of patients that are in need of emergency surgery are those with heart failure, and in this particular paper, we analyzed emergency medicine with advanced surgery protocols focusing on gastric cancer, cardiac surgery, and bleeding as well as coagulopathy following traumatic injury.

Polytrauma: update on basic science and clinical evidence

The management of multiply injured or severely injured patients is a complex and dynamic process. Timely and safe fracture fixation is a critical component of the multidisciplinary care that these patients require. Effective management of these patients, and their orthopaedic injuries, requires a strong understanding of the pathophysiology of the response to trauma and indicators of patient status, as well as an appreciation for the dynamic nature of these parameters. Substantial progress in both clinical and basic science research in this area has advanced our understanding of these concepts and our approach to management of the polytraumatized patient. This article summarizes a symposium on this topic that was presented by an international panel of experts at the 2020 Virtual Annual Meeting of the Orthopaedic Trauma Association.

Fat Embolism Syndrome: The Ambiguity of Diagnosis in the Postarthroplasty Patient: A Case Report

CASE

We present the case of an otherwise healthy, 74-year-old woman, who underwent bilateral hip arthroplasty and subsequently presented with decreased level of consciousness, mimicking a severe postoperative delirium. After several days and investigations, the diagnosis of fat embolism syndrome (FES) was reached, and appropriate management was given.

CONCLUSION

Orthopedic surgeons and their teams should consider FES as a differential diagnosis of prolonged post-operative delirium. With supportive management these patients can make a full recovery without lasting neurological symptoms. Our patient has shown no subsequent sequelae after 10-month follow-up.

Fat Embolism and Fat Embolism Syndrome

Fat embolism (FE) occurs frequently after trauma and during orthopaedic procedures involving manipulation of intramedullary contents. Classically characterized as a triad of pulmonary distress, neurologic symptoms, and petechial rash, the clinical entity of FE syndrome is much less common. Both mechanical and biochemical pathophysiologic theories have been proposed with contributions of vascular obstruction and the inflammatory response to embolized fat and trauma. Recent studies have described the relationship of embolized marrow fat with deep venous thrombosis and postsurgical cognitive decline, but without clear treatment strategies. Because treatment is primarily supportive, our focus must be on prevention. In trauma, early fracture stabilization decreases the rate of FE syndrome; however, questions remain regarding the effect of reaming and management of bilateral femur fractures. In arthroplasty, computer navigation and alternative cementation techniques decrease fat embolization, although the clinical implications of these techniques are currently unclear, illustrating the need for ongoing education and research with an aim toward prevention.

Reamer-Irrigator-Aspirator Multiuse Application in the Treatment of Chronic Osteomyelitis

Introduction

The treatment of chronic intramedullary infection of the long bones relies on microbe-specific antibiotics in conjunction with surgical removal of infected necrotic material. We discuss the use of reamer–irrigator–aspirator(RIA) for debridement of the intramedullary canal instead of conventional reaming techniques. This is the first case report to explore the use of RIA for osteomyelitis.

Case Report

We discuss the use of the RIA in treatment of a 26-year-old female presenting with chronic osteomyelitis of the left distal femoral shaft. She had normalization of infection laboratories at 6 weeks and complete resolution of symptoms at 3 months and was released at 6 months.

Conclusion

Recent exploration of the RIA system’s (Synthes®, Inc. West Chester, Philadelphia) multipurpose applications has indicated use in long bone debridement. While further exploration and high-quality studies are needed to make robust claims of efficacy, we believe that the use of RIA in the context of chronic osteomyelitis is a superior alternative to conventional reaming techniques.

Healing, nonunion, and re-operation after internal fixation of diaphyseal and distal femoral fractures: a systematic review and meta-analysis

PURPOSE

Nonunion is a highly morbid complication that exacerbates the pain, disability and financial burden of distal and diaphyseal femur fractures. This study examined the modern rates of healing, nonunion, and other complications requiring reoperation of different fixation methods for distal and diaphyseal femur fractures.

METHODS

A systematic review and meta-analysis of all records from PubMed, Embase and the Cochrane Review system was performed. Included studies had >20 acute, non-pathologic distal or diaphyseal femur fractures treated with primary internal fixation. Excluded were studies on abnormal patient/fracture populations, external fixation, or cement/bone graft use.

RESULTS

Thirty-eight studies with 2,829 femoral shaft fractures and 11 studies with 505 distal femur fractures were included. Distal fractures had a lower healing rate (86.6% vs. 93.7%) and a higher re-operation rate (13.4% vs 6.1%) than shaft fractures (p < 0.00001), primarily due to higher rates of mechanical failure (p < 0.00001). Nonunion was the most frequent complication, occurring in 4.7% of distal fractures and 2.8% of shaft fractures. There was no difference between plate and nail fixation of distal fractures in healing, nonunion, or other causes of re-operation. Shaft fractures developed nonunion in 6.6% of unreamed nails and 2.1% of reamed nails (p = 0.002). Nonunion occurred in 2.3% of antegrade nailed fractures and 1.5% of retrograde nailed fractures (p = 0.66).

CONCLUSIONS

Approximately one out of every eight distal fractures and one of every 16 shaft fractures requires re-operation. The most common cause of fixation failure is nonunion. Further research is needed to improve outcomes, particularly in distal femur fractures.

Challenges of bone tissue engineering in orthopaedic patients

Bone defects may impede normal biomechanics and the structural stability of bone as an organ. In many cases, the correction of bone defects requires extensive surgical intervention involving the use of bone-grafting techniques and other procedures in which healing is slow, there is a high risk of infection and considerable pain is provoked - with no guarantee of complete correction of the defect. Therefore, the search for surgical alternatives continues to present a major challenge in orthopaedic traumatology. The reamer-irrigator-aspirator (RIA) system, which was devised to avoid the problems that can arise with autograft harvesting from the iliac crest, consists of collecting the product of the femoral canal after reaming. The RIA technique improves osteogenic differentiation of mesenchymal stem cells, compared to bone marrow aspiration or cancellous bone harvesting from the iliac crest using a spoon. Another approach, the Masquelet technique, consists of reconstructing a long bone defect by means of an induced membrane grown onto an acrylic cement rod inserted to fill the defect; in a second surgical step, once the membrane is constituted, the cement rod is removed and cancellous autograft is used to fill the defect. Both in RIA and in the Masquelet technique, osteosynthesis is usually needed. Bone transportation by compression-distraction lengthening principles is commonly implemented for the treatment of large bone loss. However, complications are frequently encountered with these techniques. Among new techniques that have been proposed to address the problem of large bone loss, the application of stem cells in conjunction with tissue engineering techniques is very promising, as is the creation of personalised medicine (or precision medicine), in which molecular profiling technologies are used to tailor the therapeutic strategy, to ensure the right method is applied for the right person at the right time, after determining the predisposition to disease among the general population. All of the above techniques for addressing bone defects are discussed in this paper.