Does intramedullary canal irrigation reduce fat emboli? A randomized clinical trial with transesophageal echocardiography

Specific tibial landmarks to improve to accuracy of the tibial cut during total knee arthroplasty. A case control study

INTRODUCTION

More personalized alignment techniques in total knee arthroplasty (TKA) have recently been described particularly for the young and active patients. Performing the ideal tibial cut might be challenging with a conventional ancillary. Therefore the aims of this study were: (1) to describe specific tibial landmarks to optimize the tibial cut in TKA; (2) to compare the accuracy of the tibial cut with these landmarks compared to a conventional technique.

METHODS

This retrospective case-control study compared primary TKAs performed using a conventional technique with extramedullary guide associated with specific tibial landmarks. For each case, one control patient was matched based on body mass index (BMI), age, preoperative Hip Knee Ankle (HKA) angle, and Medial Proximal Tibial Angle (MPTA). All control patients were operated by the same surgeon and similar conventional technique but without landmarks. The MPTA target was to reproduce preoperative deformity with a 3° of varus limit. 34 TKA were included in each group. There was no preoperative difference between both groups. Mean age was 63 years old ± 8. Mean BMI was 32 kg/m2 ± 5. Mean HKA was 170.6° ± 2.5. Mean MPTA was 85.1° ± 2.3. The radiographic assessment was performed preoperatively and at 2 months: HKA, mechanical Medial Distal Femoral Angle (mMDFA), MPTA, tibial slope, restoration of the joint line-height.

RESULTS

The tibial landmarks corresponded to the line of insertion of the deep medial collateral ligament fibers extended to the capsular insertion above the Gerdy tubercle. The postoperative MPTA was significantly more varus (87.2° ± 1.6 in landmark group versus 88.3° ± 2.2; p = 0.027) and closer to preoperative bone deformity in landmark group (p = 0.002) with significantly less outliers than in the conventional group. There was no significant difference between both groups postoperatively for HKA (175.4° ± 2.3 versus 175.9° ± 2.5; p = 0.42); mMDFA (88.9° ± 2.3 versus 88.2° ± 2.1; p = 0.18); tibial slope (82.6° ± 1.9 versus 82.4° ± 2.6; p = 0.67), the restoration of the joint line-height (1.5 mm ± 2 versus 1.8 mm ± 2; p = 0.56).

CONCLUSION

Specific tibial landmarks during TKA can be used to increase the accuracy of the tibial cut when using personalized alignment techniques in TKA.

LEVEL OF EVIDENCE

IV.

Fat Embolism Syndrome - A Qualitative Review of its Incidence, Presentation, Pathogenesis and Management

Fat Embolism Syndrome (FES) is a poorly defined clinical phenomenon which has been attributed to fat emboli entering the circulation. It is common, and its clinical presentation may be either subtle or dramatic and life threatening. This is a review of the history, causes, pathophysiology, presentation, diagnosis and management of FES. FES mostly occurs secondary to orthopaedic trauma; it is less frequently associated with other traumatic and atraumatic conditions. There is no single test for diagnosing FES. Diagnosis of FES is often missed due to its subclinical presentation and/or confounding injuries in more severely injured patients. FES is most frequently diagnosed using the Gurd and Wilson criteria, like its rivals it is not clinically validated. Although FES is a multi-system condition, its effects in the lung, brain, cardiovascular system and skin cause most morbidity. FES is mostly a self-limiting condition and treatment is supportive in nature. Many treatments have been trialled, most notably corticosteroids and heparin, however no validated treatment has been established.

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.

An evaluation of endoprosthesis and pertrochanteric external fixator results in elderly intertrochanteric femoral fractures

Objective: In this study, 14-month clinical outcomes of the endoprosthesis and pertrochanteric external fixator application are retrospectively evaluated in elderly patients with pertrochanteric fractures. Patients and Method: A total of 45 patients of 65 years old and older (25 females and 20 males) with a mean age of 78.1, who were treated due to intertrochanteric femur fracture between November 2013 and December 2014 and whose controls could be made were included in this study. The deaths that occurred within the postoperative 1 year were not included in the study. 28 patients with endoprosthesis as Group I, and 17 patients with pertrochanteric external fixator as Group II were evaluated. Results: Table 2 shows the clinical evaluation results of the patients according to different criteria by the groups. The mean operation time was 45 min in Group I and 20 min in Group II. The external fixator application time is significantly shorter. The mean hospital stay was 14 days for Group I and 10 days for Group II. The hospital stay period of the external fixator group is 4 days shorter. While 7 patients were taken into the intensive care unit in Group I postoperatively, only 1 patient was taken into the same unit in Group II. This difference was significantly in favor of the external fixator group. While 14 patients in Group I needed a preoperative and postoperative blood transfusion, no patient needed blood transfusions in Group II. External fixator application is significantly more advantageous in terms of patient hemodynamics. The mean time to postoperatively move the extremity independently in the bed was 24 hours in Group I and 36 hours in Group II. All patients were exposed to the Harris hip scoring in the postoperative 12. month (the fixator was removed for the external fixator group). Conclusion: In addition to internal fixation options and endoprosthesis applications in elderly intertrochanteric femoral fractures, an external fixator may also be a good treatment alternative with appropriate patient selection and proper application in accordance with the technique thanks to its short surgical time, less blood loss and easy applicability.

A study on dynamic monitoring, components, and risk factors of embolism during total knee arthroplasty

BACKGROUND

Fat embolism is a common complication of orthopedic surgery. However, the exact component and risk factor responsible for this complication remains unelucidated. This study aimed to detect the origin of the pulmonary embolus and identify relevant risk factors of pulmonary embolism in total knee replacement.

METHODS

A total of 40 osteoarthritis patients who underwent primary unilateral TKA were recruited into this study. Transesophageal echocardiography (TEE) was utilized to dynamically monitor the embolism. Pulmonary arterial pressure was recorded and biopsies were obtained from the medullary cavity during surgery.

RESULTS

After tourniquet release, the arterial embolism was observed by TEE to have a peak signal at 30 seconds when pulmonary arterial pressure was increased by 25% to 40% (P = .002). The pathology study of the embolism revealed its bone marrow origin. Total embolus quantity was positively correlated with age (P = .021), body mass index (BMI, P = .041), and fat content of the bone marrow (P = .003). Logistic regression analysis revealed that the fat content of the marrow (OR: 1.432, 95% CI: 1.335-1.592), age (OR: 1.632, 95% CI: 1.445-1.832), and BMI (OR: 1.231, 95% CI: 1.032-1.381) were risk factors for pulmonary hypertension.

CONCLUSION

This study revealed that the embolus detected in the right atrium was derived from bone marrow tissues, and this led to pulmonary arterial pressure fluctuations after tourniquet release. Therefore, elderly patients who have high BMI or bone marrow fat content are at high-risk for pulmonary fat embolism during TKA.

Arachidonic acid causes hidden blood loss-like red blood cell damage through oxidative stress reactions

BACKGROUND

Hidden blood loss (HBL) often occurs in the prosthetic replacement for joint, but the mechanism is still not clear.

MATERIALS AND METHODS

This study tried to establish an animal model of HBL by injecting arachidonic acid (AA) into the Sprague-Dawley rats. Different concentrations of AA were injected into the tail veins of the rats, and blood samples were collected before and after administration at 24, 48, and 72 h. A complete blood count was obtained by to find the hemoglobin (Hb) and red blood cell (RBC) count changes. The glutathione peroxidase (GSH-PX) and total superoxide dismutase (T-SOD) activities and hydrogen peroxide (H₂O₂) levels were detected. The morphological changes of erythrocyte were observed under a polarizing microscope. The absorbance values of the blood samples were tested to determine the presence of ferryl Hb.

RESULTS

HBL occurred in the experimental groups when the concentration of AA reached 10 mmol/L; Hb and RBC values decreased sharply at 24- and 48-h postinjection. This was followed by reduced activities of GSH-PX and T-SOD and decreased levels of H₂O₂. Moreover, the pathologic changes of red cell morphology mainly presented as pleomorphic RBC morphology, including cell rupture. The absorbance values of the blood samples were in accordance with ferryl Hb features. RBC and Hb values were relatively stable at 72 h. The GSH-PX and T-SOD activities and H₂O₂ levels gradually increased up to a balanced state.

CONCLUSIONS

The study concluded that high concentrations of AA can induce oxidative stress reactions in the body, causing acute injury of RBCs, which is closely related to HBL.

Holistic ultrasound in trauma: An update

Holistic ultrasound is a total body examination using an ultrasound device aiming to achieve immediate patient care and decision making. In the setting of trauma, it is one of the most fundamental components of care of the injured patients. Ground-breaking imaging software allows physicians to examine various organs thoroughly, recognize imaging signs early, and potentially foresee the onset or the possible outcome of certain types of injuries. Holistic ultrasound can be performed on a routine basis at the bedside of the patients, at admission and during the perioperative period. Trauma care physicians should be aware of the diagnostic and guidance benefits of ultrasound and should receive appropriate training for the optimal management of their patients. In this paper, the findings of holistic ultrasound in trauma patients are presented, with emphasis on the lungs, heart, cerebral circulation, abdomen, and airway. Additionally, the benefits of ultrasound imaging in interventional anaesthesia techniques such as ultrasound-guided peripheral nerve blocks and central vein catheterization are described.

Establishing a Customized Guide Plate for Osteotomy in Total Knee Arthroplasty Using Lower-extremity X-ray and Knee Computed Tomography Images

BACKGROUND

The conventional method cannot guarantee the precise osteotomies required for a perfect realignment and a better prognosis after total knee arthroplasty (TKA). This study investigated a customized guide plate for osteotomy placement in TKAs with the aid of the statistical shape model technique using weight-bearing lower-extremity X-rays and computed tomography (CT) images of the knee.

METHODS

From October 2014 to June 2015, 42 patients who underwent a TKA in Guizhou Provincial People's Hospital were divided into a guide plate group (GPG, 21 cases) and a traditional surgery group (TSG, 21 cases) using a random number table method. In the GPG group, a guide plate was designed and printed using preoperative three-dimensional measurements to plan and digitally simulate the operation. TSG cases were treated with the conventional method. Outcomes were obtained from the postoperative image examination and short-term follow-up.

RESULTS

Operative time was 49.0 ± 10.5 min for GPG, and 62.0 ± 9.7 min in TSG. The coronal femoral angle, coronal tibial angle, posterior tibial slope, and the angle between the posterior condylar osteotomy surface and the surgical transepicondylar axis were 89.2 ± 1.7°, 89.0 ± 1.1°, 6.6 ± 1.4°, and 0.9 ± 0.3° in GPG, and 86.7 ± 2.9°, 87.6 ± 2.1°, 8.9 ± 2.8°, and 1.7 ± 0.8° in TSG, respectively. The Hospital for Special Surgery scores 3 months after surgery were 83.7 ± 18.4 in GPG and 71.5 ± 15.2 in TSG. Statistically significant differences were found between GPG and TSG in all measurements.

CONCLUSIONS

A customized guide plate to create an accurate osteotomy in TKAs may be created using lower-extremity X-ray and knee CT images. This allows for shorter operative times and better postoperative alignment than the traditional surgery. Application of the digital guide plate may also result in better short-term outcomes.