Total Joint Arthroplasty in Patients With Atrial Septal Defects: What Are the 90-Day Complications?

Background: Congenital heart defects, such as atrial septal defects (ASDs) and patent foramen ovale (PFO), may increase the risk of embolic events in total hip or knee arthroplasty (THA/TKA). The objective of this study was to determine the 90-day incidence of intraoperative and postoperative embolic events and all other complications in patients with a known ASD/PFO who underwent primary hip and knee arthroplasty. Methods: This is a retrospective review of 160 patients with ASD/PFO undergoing 196 primary arthroplasties (94 THAs, 102 TKAs) at a single institution. The mean age was 64 years (standard deviation [SD] 11.1), 40.6% were male, and average body mass index was 31 kg/m2 (SD 7.2). The mean follow-up period was 19 months (SD 16). Forty-three percent of patients were on anticoagulation preoperatively. All patients received postoperative thromboprophylaxis (48% aspirin, 31% direct oral anticoagulants, 18% warfarin, 3% enoxaparin). Results: There were no embolic events identified. Fourteen patients (7%) developed complications within 90 days. Three had bleeding complications, and 8 had other nonoperative complications, which were all managed conservatively and had uneventful recoveries. Additionally, 3 patients had complications requiring reoperations: 2 for periprosthetic fractures (1 THA, 1 TKA) and 1 for a periprosthetic infection (TKA). Conclusions: In this cohort of patients with a known ASD/PFO undergoing THAs and TKAs, there were no cases of embolic events. However, it would be advisable to have a thorough cardiology evaluation to assess potential risks and benefits of defect repair prior to total joint arthroplasty and to reduce the risk of paradoxical embolic events and the necessity of potent anticoagulation. Level of evidence: Prognostic Level IV.

Multimodal Thromboprophylaxis in Patients With a History of Venous Thromboembolism Undergoing Primary and Revision Knee Arthroplasty.

Background: Patients with a history of venous thromboembolism (VTE) undergoing total knee arthroplasty (TKA) are at a high risk of postoperative VTE. Purpose: In this high-risk population, we sought to evaluate the safety and efficacy of multimodal thromboprophylaxis. The regimen consisted of discontinuation of procoagulant medications, VTE risk stratification, regional anesthesia, rapid mobilization, perioperative use of pneumatic compression devices, vigorous ankle dorsiflexion during the recovery period, and chemoprophylaxis tailored to the patient's risk of VTE. Methods: We conducted a retrospective chart review of 141 consecutive patients with a history of VTE who underwent 177 elective TKA procedures between 2005 and 2019 by 2 arthroplasty surgeons at a single institution. The patients had a history of deep venous thrombosis (DVT) (n = 127; 72%), pulmonary embolism (PE) (n = 20; 11%), or both (n = 30; 17%). Postoperative chemoprophylaxis included aspirin (n = 20; 11%), anticoagulation (n = 135; 77%), or a combination of aspirin and anticoagulation (n = 21; 12%). Complications within 120 days, including VTE events, wound complications, bleeding, and unplanned readmissions, were recorded, as was 1-year mortality. Results: Five patients (2.8%) developed symptomatic DVT (3 distal, 2 proximal), and 4 patients (2.3%) developed symptomatic PE. The most common postdischarge complications were wound infection (n = 6; 3.4%) and stiffness requiring manipulation under anesthesia (n = 5; 2.8%). There was 1 emergency room visit and 13 unplanned readmissions; 3 patients developed intra-articular hematomas or prolonged wound drainage and recovered uneventfully. All patients were alive 1 year after surgery. Conclusion: The findings of this retrospective study suggest that multimodal prophylaxis may be safe and effective in patients with a history of VTE undergoing primary and revision TKA. More rigorous study is warranted.

Multimodal prophylaxis in patients with a history of venous thromboembolism undergoing primary elective hip arthroplasty.

AIMS: We studied the safety and efficacy of multimodal thromboprophylaxis in patients with a history of venous thromboembolism (VTE) who undergo total hip arthroplasty (THA) within the first 120 postoperative days, and the mortality during the first year. Multimodal prophylaxis includes discontinuation of procoagulant medications, VTE risk stratification, regional anaesthesia, an intravenous bolus of unfractionated heparin prior to femoral preparation, rapid mobilization, the use of pneumatic compression devices, and chemoprophylaxis tailored to the patient's risk of VTE. METHODS: Between 2004 to 2018, 257 patients with a proven history of VTE underwent 277 primary elective THA procedures by two surgeons at a single institution. The patients had a history of deep vein thrombosis (DVT) (186, 67%), pulmonary embolism (PE) (43, 15.5%), or both (48, 17.5%). Chemoprophylaxis included aspirin (38 patients), anticoagulation (215 patients), or a combination of aspirin and anticoagulation (24 patients). A total of 50 patients (18%) had a vena cava filter in situ at the time of surgery. Patients were followed for 120 days to record complications, and for one year to record mortality. RESULTS: Postoperative VTE was diagnosed in seven patients (2.5%): DVT in five, and PE with and without DVT in one patient each. After hospitalization, three patients required readmiss-ion for evacuation of a haematoma, one for wound drainage, and one for monitoring of an elevated international normalized ratio (INR). Seven patients died (2.5%). One patient died five months postoperatively of a PE during open thrombectomy. She had discontinued anticoagulation. One patient died of a haemorrhagic stroke while receiving Coumadin. PE or bleeding was not suspected in the remaining five fatalities. CONCLUSION: Multimodal prophylaxis is safe and effective in patients with a history of VTE. Postoperative anticoagulation should be prudent as very few patients developed VTE (2.5%) or died of suspected or confirmed PE. Mortality during the first year was mostly unrelated to either VTE or bleeding. Cite this article: Bone Joint J 2020;102-B(7 Supple B):71-77.

Polished, Collarless, Tapered, Cemented Stems for Primary Hip Arthroplasty May Exhibit High Rate of Periprosthetic Fracture at Short-Term Follow-Up.

BACKGROUND: Cemented stems are designed to follow 1 of 2 principles of fixation: composite beams or slide taper. Stems in the latter category have a collarless, polished, tapered (CPT) design and subside into the cement mantle, creating hoop stresses. We compared the rate of periprosthetic fracture (PPF) of stem designed with these 2 principles of fixation. In addition, we examined radiographic factors that may predispose to the development of PPF. METHODS: We retrospectively reviewed all patients who underwent primary THA by a single surgeon using highly polished cemented stems. PPF rates were compared between CPT stems (follow-up, 21 months; standard deviation [SD], 22) and composite beam stems (follow-up, 21.7 months; SD, 26). Demographic data were compared between patients with and without a PPF. Three preoperative radiographic parameters (canal bone ratio [CBR], canal-calcar ratio, and canal flare index), stem alignment, and cement mantle were compared in match-paired patients with and without a PPF (1:34). RESULTS: Seven of 1460 THA patients developed a PPF (0.479%); 4 hips of 185 with a CPT stem (2.2%); and 3 of 1275 hips with a composite beam stem (0.23%; P = .0064). Three of the 4 PPFs in the CPT group and none in the composite beam group were classified as Vancouver B2. The CBR in patients with a PPF was 0.50 (SD, 0.07) and 0.43 (SD, 0.07) in the match cohort of hips without PPF (P = .013). CONCLUSION: CPT stems may be associated with a higher risk of PPF that often require reoperation. An increased CBR may be a risk factor for postoperative PPF.

The Clinical Severity of Patients Diagnosed With an In-Hospital Pulmonary Embolism Following Modern, Elective Joint Arthroplasty Is Unrelated to the Location of Emboli in the Pulmonary Vasculature.

BACKGROUND: In the event of a postoperative pulmonary embolism (PE), it is generally believed that patients with centrally located emboli will have worse clinical symptoms than those with segmental or subsegmental ones. We studied if a relationship exists between the clinical severity at the time of PE diagnosis and the location of the emboli within the pulmonary vasculature. METHODS: All 269 patients who developed an in-hospital, computed tomography pulmonary angiography-proved, PE following elective total hip arthroplasty or total knee arthroplasty in our institution were studied. The clinical severity of the PE was calculated using the Pulmonary Embolism Severity Index (PESI) that classifies patients in 5 classes (class 5: most severe). All computed tomography pulmonary angiographies were re-reviewed to determine the location of the emboli within the pulmonary vasculature (central, segmental, or subsegmental-unilateral or bilateral). The association between PESI and the PE location was examined. RESULTS: The most proximal location of the emboli was central in 62, segmental in 139, and subsegmental in 68. There were 180 unilateral and 89 bilateral PE patients. There was no association between the PESI and the location of the emboli within the pulmonary vasculature (P = .32). Patients with bilateral or unilateral lung involvement had similar PESI (P = .78). CONCLUSION: The PESI, a recognized, validated predictor of mortality after PE was similar in patients with central, segmental, or subsegmental PE; and in patients with unilateral or bilateral lung involvement. The present study may aid clinicians while assessing and discussing the severity of PE symptoms with patients at the time of diagnosis.

One-Year All-Cause Mortality of Patients Diagnosed as Having In-Hospital Pulmonary Embolism After Modern Elective Joint Arthroplasty Is Low And Unaffected By Radiologic Severity.

BACKGROUND: We studied the 1-year complication rate of patients diagnosed as having a pulmonary embolism (PE) after elective total hip arthroplasty (THA) and total knee arthroplasty (TKA) surgery and the distribution of emboli in the pulmonary circulation, and determined if a relationship exists between the location of the PE and age, gender, body mass index, preoperative predisposing factors, American Society of Anesthesiology classification, type of surgery, prophylaxis, hospital stay, transfer to a higher level of care, and mortality. METHODS: Two hundred sixty-nine patients who developed an in-hospital PE proved by computed tomography pulmonary angiography after elective THA or TKA between 2005 and 2012 were studied. RESULTS: The most proximal location of the emboli was central in 62, segmental in 139, and subsegmental in 68. Nineteen patients (7%) developed a bleeding complication during PE treatment. Twenty-nine patients (11%) were readmitted during the first year. Two patients (0.74%) died: one had a segmental PE after TKA. He died 11 months after surgery due to an autopsy-proven sepsis. The second patient developed a segmental PE after THA. She was anticoagulated, developed an intracranial bleed, and died 8 months after surgery. Multivariate analysis showed that demographic variables, American Society of Anesthesiology class, preoperative comorbidities (with the exception of arrhythmia), and the presence of preoperative predisposing factors had no effect in the location of the PE. CONCLUSION: The 1-year mortality rate of these patients is low. Death can be caused by bleeding complications secondary to anticoagulation or by unrelated conditions. This information may aid clinicians while counseling patients who developed a PE after surgery, particularly those with small subsegmental emboli.

Risk Factors of Heterotopic Ossification Following Total Hip Arthroplasty in Patients With Ankylosing Spondylitis.

This study was to identify the risk factors of heterotopic ossification (HO) after total hip arthroplasty (THA) in ankylosing spondylitis. We analyzed 47 hips (24 patients) with ankylosing spondylitis that underwent primary THA. The incidence of HO was 14.9%. The risk factors were divided into modifiable and nonmodifiable factors. Female gender (P=0.008), preoperative ankylosed hip (P<0.001), occurrence of HO in previous surgery (P=0.036) were nonmodifiable risk factors which increased the prevalence of HO. Of the various modifiable risk factors, elevated preoperative ESR (P=0.007), elevated preoperative CRP (P=0.004) and prolonged duration of surgery (P=0.014) were associated with increased occurrence of HO. Perioperative medical intervention to reduce inflammation (ESR and CRP) may help to decrease HO.

Medial patellofemoral ligament (MPFL) reconstruction improves radiographic measures of patella alta in children.

BACKGROUND: Patellofemoral instability has previously been associated with patella alta. The purpose of this study was to evaluate adolescents undergoing MPFL reconstruction for standardized indices of patellar height on pre- and post-operative radiographs to determine if these radiographic parameters change after MPFL reconstruction. METHODS: Twenty-seven children (mean age 14.9years old) who underwent MPFL reconstruction without a distal realignment procedure were evaluated pre- and post-operatively for Insall-Salvati Ratio, Modified Insall-Salvati Ratio, and Caton-Deschamps Index by three blinded raters. Intrarater reliability and interrater reliability were calculated for each index, and means of each were compared pre- and post-operatively to determine if MPFL reconstruction was associated with improved patellar height. RESULTS: All three indices of patellar height indicated that there was patella alta present in this cohort preoperatively. Furthermore, all three measures were significantly improved postoperatively (paired t-tests, P<0.001 for all) to within normal childhood ranges. Interrater reliability was excellent for both the Insall-Salvati Ratio (ICC=0.89) and Caton-Deschamps Index (ICC=0.78), and adequate for the Modified Insall-Salvati Ratio (ICC=0.57); intrarater reliability was excellent for all three (ICCs: 0.91, 0.82, 0.80 respectively). CONCLUSIONS: MPFL reconstruction in children using hamstring autograft was associated with consistently improved patellar height indices to within normal childhood ranges. This associated improvement of patellar height as measured on a lateral radiograph may subsequently improve patellofemoral mechanics by drawing the patella deeper and more medially into the trochlear groove. LEVEL OF EVIDENCE: Level 4.

Acetabular component orientation in total hip arthroplasty: the impact of obesity.

INTRODUCTION: Acetabular component position can be an important determinant of joint stability and bearing surface wear after THA. Nonetheless, the incidence of malpositioning is high. Patient obesity, low surgeon volume, and minimally invasive approaches are known risk factors for malposition. As the incidence of obesity continues to increase, it is important to recognise its effect on intraoperative component positioning in THA. OBJECTIVES: Our goal was to assess the impact of obesity on component position for a high-volume surgeon using a standard postero-lateral approach. METHODS: A consecutive series of 120 obese (BMI >30, mean BMI 34.4) and 120 non-obese patients (mean BMI 25.4), who had undergone primary THA by a single surgeon, were included in our retrospective study. AP pelvis and cross-table radiographs obtained at the first postoperative visit were analysed using EBRA software to determine inclination and anteversion angles. Optimal position was defined as 30-45º of inclination and 5-25º of anteversion. RESULTS: Mean inclination and anteversion were 40.6 (+/-5.4º) and 16.6 (+/-5.5º) respectively, in the obese group and 39º (+/-5.0º) and 16.2º (+/-7.5º) in the non-obese group. In the obese group 89 (74%) patients were within the desired range for both measurements, 31 (26%) were out of range in at least one, compared to 91 (76%) and 29 (24%) in the non-obese group, respectively. The overall incidence of malpositioning was 25% for both groups. Among outliers, mean deviation from the optimal range was ≤3.8º in both groups. CONCLUSIONS: The risk of component malpositioning in THA may be reduced when surgery is performed by an experienced, high volume surgeon utilising a standard posterolateral approach. In this setting the deleterious effect of obesity may be overcome.

[Effect of preoperative donation of autologous blood on venous thromboembolism disease after total hip replacement].

OBJECTIVE: To evaluate the effect of preoperative donation of autologous bood on venous thromboembolism (VTE) after total hip arthroplasty (THA). METHODS: Between Jan. 2007 and March. 2010,912 consecutive patients who had THAs performed in Hosptal for Special Surgery were collected, excluded patients with thrombocytopenia or pre-exising bleeding diathesis and patients for whom epidural analgesia was not possible. Among them, there were 428 males and 484 females with an average age of (65.28 +/- 11.90) years (ranged from 24 to 93 years). Among them, 835 cases (91.3%) had osteoarthritis, 32 cases (3.6%) had osteonerrosis, 20 cases (2.3%) had dysplasia, 20 cases (2.2%) had rheumatoid arthritis, and 5 cases (0.6%) had other diagnoses. The surgeries were performed under hypotensive epidural anestheisa (mean arterial pressure between 45 to 55 mm Hg) and through a posterolateral approach, minimizing the duration of femoral vein obstruction and reducing the load of intramedullary content to the venous system by repeated pulsatile lavage and aspiration of the femoral canal. The lower extremity was in the neutral position while working on the acetabulum and flexed and internally rotated while working on the femur. Whenever possible,the lower extremity was extended to a neutral position to restore femoral venous flow. Patients received one bolus of unfractionated intravenous heparin (10 to 15 U/kg), 1 to 2 minutes before femoral canal preparation. All patients were followed up at least 3 months postoperatively. No patient was lost to followed-up. RESULTS: Seven hundreds and fifty-two patients donated autologous blood before THA, 160 did not donate autologoud blood. The incidence of clinical symoptomatic VTE was 1.3% (11/912). Among the 11 patients with clinical symoptomatic VTE, 5 donated blood pre-operation (0.66%, 5/752) and 6 did not donate pre-operation (3.8%, 6/160). The rate of VTE after THA between autologous blood donation and no blood donation was statistically significant (P = 0.021 < 0.05. The incidence of deep vein thrombosis was 0.8%(8/ 912). Three patients had a symptomatic of Pulmonary embolism. CONCLUSION: A significant decrease in the incidence of VTE is noted in those who had donated blood preoperatively compared with those who had not.

Thrombophilic abnormalities in patients with or without pulmonary embolism following elective spinal surgery: a pilot study.

BACKGROUND: Significance of the thrombophilic abnormalities in development of venous thromboembolism (VTE) has been studies with total hip arthroplasty and acute traumatic spinal cord injury. However, their role as risk factors for VTE in elective spinal surgery remains to be determined. QUESTIONS/PURPOSES: To determine the role of thrombophilic abnormalities in the development of pulmonary embolism (PE) following elective spine surgery. METHODS: Case and control groups were created in patients who had undergone elective spinal surgery for degenerative conditions. The PE group comprised 12 patients whose post-operative course was complicated by development of PE. The control group included 12 patients with an uneventful post-operative course. Demographic data including age, gender and surgical procedures were matched between the PE group and the control group. Both groups were evaluated for thrombophilic and hypofibrinolytic risk factors at 3 months post-operatively or later. Blood tests were performed to measure fasting serum homocysteine, antithrombin III, and protein C. Molecular genetic testing was conducted for detection of the plasminogen activator inhibitor-1 4G/4G, and prothrombin 3 UTR gene mutations. RESULTS: Heterozygous mutation (G20201A) of prothrombin was detected in two patients (16.7%) in the PE group, whereas no such mutation was noted in the control group. Plasminogen activator inhibitor-1 4G/4G homozygous mutation was seen in three in the PE group and two in the control group. Of homocysteine, antithrombin III and protein C, only one patient in each group showed abnormal levels of homocysteine. In total, there half of the patients in the PE group had at least one thrombophilic abnormality, whereas three (25%) patients showed such abnormality in the control group. CONCLUSION: These findings suggest the involvement of thrombophilic abnormalities, especially the heterozygous G20201A mutation, in the development of PE in patients undergoing elective spinal surgery.

Computerized virtual surgery demonstrates where acetabular rim osteophytes most reduce range of motion following total hip arthroplasty.

BACKGROUND: Acetabular osteophytes are common findings during total hip arthroplasty (THA). PURPOSE: This study was designed to determine the extent to which osteophytes may limit range of motion (ROM) and in which locations impingement is likely to occur if osteophytes are not removed during surgery. METHODS: Computer-aided design was used to compare ROM of a modern hip implant in four cadaver models with and without 10-mm acetabular rim osteophytes added. A clock face, with 12 o'clock at the superior pole of the right acetabulum, was used to map impingement. RESULTS: The osteophyte model limited ROM in flexion (101° v. 113°, p = 0.03), 90° of flexion with internal rotation (16.7° v. 31.6°, p = 0.01), and external rotation (30.4° v. 49.5°, p = 0.01). Impingement occurred between 7 and 8 o'clock in external rotation and 1 and 2 o'clock in the other two motions. CONCLUSIONS: Osteophytes in these positions have the greatest impact on ROM and should be removed during THA.

Safety and efficacy of multimodal thromboprophylaxis following total knee arthroplasty: a comparative study of preferential aspirin vs. routine coumadin chemoprophylaxis.

Multimodal thromboprophylaxis encompasses preoperative VTE risk stratification, regional anesthesia, mechanical prophylaxis, and early mobilization. We determined if aspirin can be safely used for adjuvant chemoprophylaxis in patients who have a low thromboembolic risk. 1016 consecutive patients undergoing TKA received multimodal thromboprophylaxis. Aspirin was used in 67% of patients and Coumadin 33% (high risk patients, or who were on Coumadin before surgery). This study group was compared to 1001 consecutive patients who received multimodal thromboprophylaxis and routine Coumadin chemoprophylaxis. There was no significant difference in rates of VTE, PE, bleeding, complications, readmission and 90-day mortality between the two groups. There was a significantly higher rate of wound related complications in the control group (p=0.03). Multimodal thromboprophylaxis with aspirin given to the majority of patients at a low VTE risk is safe and effective in patients undergoing primary TKA.

The effect of TNFα secreted from macrophages activated by titanium particles on osteogenic activity regulated by WNT/BMP signaling in osteoprogenitor cells.

Wear particles are the major cause of osteolysis associated with failure of implant following total joint replacement. During this pathologic process, activated macrophages mediate inflammatory responses to increase osteoclastogenesis, leading to enhanced bone resorption. In osteolysis caused by wear particles, osteoprogenitors present along with macrophages at the implant interface may play significant roles in bone regeneration and implant osteointegration. Although the direct effects of wear particles on osteoblasts have been addressed recently, the role of activated macrophages in regulation of osteogenic activity of osteoblasts has scarcely been studied. In the present study, we examined the molecular communication between macrophages and osteoprogenitor cells that may explain the effect of wear particles on impaired bone forming activity in inflammatory bone diseases. It has been demonstrated that conditioned medium of macrophages challenged with titanium particles (Ti CM) suppresses early and late differentiation markers of osteoprogenitors, including alkaline phosphatase (ALP) activity, collagen synthesis, matrix mineralization and expression of osteocalcin and Runx2. Moreover, bone forming signals such as WNT and BMP signaling pathways were inhibited by Ti CM. Interestingly, TNFα was identified as a predominant factor in Ti CM to suppress osteogenic activity as well as WNT and BMP signaling activity. Furthermore, Ti CM or TNFα induces the expression of sclerostin (SOST) which is able to inhibit WNT and BMP signaling pathways. It was determined that over-expression of SOST suppressed ALP activity, whereas the inhibition of SOST by siRNA partially restored the effect of Ti CM on ALP activity. This study highlights the role of activated macrophages in regulation of impaired osteogenic activity seen in inflammatory conditions and provides a potential mechanism for autocrine regulation of WNT and BMP signaling mediated by TNFα via induction of SOST in osteprogenitor cells.

Guillain-barré syndrome mimicking nerve injury after total hip arthroplasty.

BACKGROUND: Guillain-Barré syndrome (GBS) is a rare, acute, inflammatory demyelinating polyneuropathy with a presentation of progressive ascending motor weakness of the extremities, which may extend to the respiratory muscles and require mechanical support. CASE DESCRIPTION: This case describes a healthy male who developed GBS 1 week following otherwise an uncomplicated bilateral total hip arthroplasty surgery. The diagnosis was made based on physical exam significant for bilateral lower extremity weakness and diffuse arreflexia, and confirmed by nerve conduction studies. There were no effects on respiratory function, and the patient underwent a gradual recovery, with near complete return of motor function by 10 weeks following surgery and no functional deficits at 1 year following surgery. Functional activity levels are maintained 4 years postoperatively. LITERATURE REVIEW: A literature review is presented. While GBS has been described in the literature following several different forms of surgery and anesthesia, cases after orthopedic surgery are exceedingly rare. PURPOSES AND CLINICAL RELEVANCE: This case demonstrates that GBS may occur following orthopedic, including total joint arthroplasty, surgery. The presentation of GBS can be variable, but the hallmarks are areflexia and diffuse ascending weakness, with or without sensory symptoms. Rapid diagnosis and treatment are critical for preventing disability and life-threatening sequelae.

Historical perspective on two-stage reimplantation for infection after total hip arthroplasty at Hospital for Special Surgery, New York City.

In this article, we report on our use of a 2-stage exchange in managing infected total hip arthroplasties (THAs) at the Hospital for Special Surgery in New York City. This protocol involves resection arthroplasty, 6 weeks of intravenous antibiotics to obtain a minimum "postpeak" serum bactericidal titer (SBT) of 1:8, and reimplantation. Over the past 20 years, we have conducted several studies showing the effectiveness of this treatment. Since our previous report was published in 1994, prevalence of multidrug-resistant (MDR) organisms has increased significantly. In 2008, we set out to determine if 2-stage exchange remains an effective treatment for newer pathogens, many of which are MDR. The overall eradication rate was 95% (80/84 hips). All 21 MDR pathogens implicated in the infected THAs were eradicated. We conclude that 2-stage exchange with a standard 1:8 minimum SBT remains an effective treatment even when resistant infections are involved.

Multimodal prophylaxis for venous thromboembolic disease after total hip and knee arthroplasty: current perspectives.

Life-threatening in the short term and leading to a high level of morbidity in the long term, venous thromboembolism (VTE) is the most fearful complication following lower limb arthroplasty. With advances in surgical procedure, anesthetic management and postoperative convalescence have altered the risks of venous thromboembolism after total joint arthroplasty in the lower extremity. The pathogenesis of VTE is multifactorial and includes the well-known Virchow's triad of hypercoagulability, venous stasis and endothelial damage. Therefore, it is appropriate to use a multimodal approach to thromboprophylaxis. Despite extensive research, the ideal multimodal prophylaxis against venous thrombolism has not been identified. So this article reviews the recent developments in multimodal prophylaxis for thromboembolism after total joint arthroplasty.

Perioperative pulmonary circulatory changes during bilateral total hip arthroplasty under regional anesthesia.

BACKGROUND AND OBJECTIVES: The transient and rarely clinically relevant effect of bone and cement embolization during unilateral joint arthroplasty is a known phenomenon. However, available studies do not address events surrounding bilateral total hip arthroplasties, during which embolic load is presumably doubled. To elucidate events surrounding this increasingly used procedure and assess the effect on the pulmonary hemodynamics in the intraoperative and postoperative periods, we studied 24 subjects undergoing cemented bilateral total hip arthroplasty during the same anesthetic session. MATERIALS: Twenty-four patients without previous pulmonary history undergoing cemented bilateral total hip arthroplasty under controlled epidural hypotension were enrolled. Pulmonary artery catheters were inserted and hemodynamic variables were recorded at baseline, 5 mins after the implantation of each hip joint, 1 hr and 1 day after surgery. Mixed venous blood gases and complete blood counts were analyzed at every time point. RESULTS: An increase in pulmonary vascular resistance was observed after the second but not the first hip implantation when compared with values at incision. Pulmonary vascular resistance remained elevated 1 hr after surgery. Pulmonary artery pressures were significantly elevated on postoperative day 1 compared with those at baseline. The white blood cell count increased in response to the second hip implantation but not the first compared with incision. CONCLUSIONS: The embolization of material during bilateral total hip arthroplasty is associated with prolonged increases in pulmonary artery pressures and vascular resistance, particularly after completion of the second side. Performance of bilateral procedures should be cautiously considered in patients with diseases suggesting decreased right ventricular reserve.

Risk factors for perioperative mortality after lower extremity arthroplasty: a population-based study of 6,901,324 patient discharges.

The goal of this study was to provide nationally representative data on characteristics of patients who died after hip and knee arthroplasty and to determine risk factors for such outcome. Using national in-patient data collected between 1990 and 2004, we identified a cumulative in-hospital mortality rate of 0.35% among an estimated 6,901,324 procedures. The strongest independent risk factors for in-hospital mortality were pulmonary embolism and cerebrovascular complications, which increased the odds for a fatal outcome by approximately 40-fold. Preoperative risk factors for in-hospital mortality were revision total hip arthroplasty, advanced age, and the presence of a number of comorbid diseases, predominantly dementia, renal, and cerebrovascular disease. Our results can be used to identify patients at risk for fatal outcome and implement interventions to reduce such risk.