Venous thromboembolic prophylaxis after simultaneous bilateral total knee arthroplasty: aspirin versus warfarin.

AIMS: The aims of this study were to compare the efficacy of two agents, aspirin and warfarin, for the prevention of venous thromboembolism (VTE) after simultaneous bilateral total knee arthroplasty (SBTKA), and to elucidate the risk of VTE conferred by this procedure compared with unilateral TKA (UTKA). PATIENTS AND METHODS: A retrospective, multi-institutional study was conducted on 18 951 patients, 3685 who underwent SBTKA and 15 266 who underwent UTKA, using aspirin or warfarin as VTE prophylaxis. Each patient was assigned an individualised baseline VTE risk score based on a system using the Nationwide Inpatient Sample. Symptomatic VTE, including pulmonary embolism (PE) and deep vein thrombosis (DVT), were identified in the first 90 days post-operatively. Statistical analyses were performed with logistic regression accounting for baseline VTE risk. RESULTS: The adjusted incidence of PE following SBTKA was 1.0% (95% confidence interval (CI) 0.86 to 1.2) with aspirin and 2.2% (95% CI 2.0 to 2.4) with warfarin. Similarly, the adjusted incidence of VTE following SBTKA was 1.6% (95% CI 1.1 to 2.3) with aspirin and 2.5% (95% CI 1.9 to 3.3) with warfarin. The risk of PE and VTE were reduced by 66% (odds ratio (OR) 0.44, 95% CI 0.25 to 0.78) and 38% (OR 0.62, 95% CI 0.38 to 1.0), respectively, using aspirin. In addition, the risk of PE was 204% higher for patients undergoing SBTKA relative to those undergoing UTKA. For each ten-point increase in baseline VTE risk, the risk of PE increased by 25.5% for patients undergoing SBTKA compared with 10.5% for those undergoing UTKA. Patients with a history of myocardial infarction or peripheral vascular disease had the greatest increase in risk from undergoing SBTKA instead of UTKA. CONCLUSION: Aspirin is more effective than warfarin for the prevention of VTE following SBTKA, and serves as the more appropriate agent for VTE prophylaxis for patients in all risk categories. Furthermore, patients undergoing SBTKA are at a substantially increased risk of VTE, even more so for those with significant underlying risk factors. Patients should be informed about the risks associated with undergoing SBTKA. Cite this article: Bone Joint J 2018;100-B(1 Supple A):68-75.

Management of arthritis of the hip in the young adult.

Arthritis of the hip in the young adult can be a disabling condition. Recent years have witnessed extensive research related to the management of this condition. This article reviews the current status with regard to aetiology, diagnosis and treatment of arthritis of the hip in the young adult.

Fixed minidose versus-adjusted low-dose warfarin after total joint arthroplasty: a randomized prospective study.

Widespread use of adjusted low-dose warfarin has been limited by the inconvenience of outpatient laboratory monitoring and the perceived risk of bleeding complications. We sought to determine if the dose of warfarin could be lowered safely even further, eliminating the need for laboratory monitoring and lowering the complication rate. Two hundred forty-five Patients undergoing primary total joint arthroplasty (n = 245) were randomized prospectively to adjusted low-dose warfarin (international normalized ratio [INR], 1.4-1.8) or fixed minidose warfarin (2 mg daily, regardless of INR) before hospital discharge. Prophylaxis continued for 6 weeks, with twice-weekly laboratory monitoring. Patients were followed for bleeding, thromboembolic events, and minor reported complications of warfarin therapy. With the numbers available, the rates of thromboembolic and bleeding events were not significantly different using equivalence analysis. Of patients in the fixed group, 8% had INRs >3.1, necessitating a decrease in dosage to 1 mg. Although such a fixed-dose protocol may simplify outpatient prophylaxis, intermittent monitoring still would be required because a subset of patients achieve a moderate level of anticoagulation and would be at risk for bleeding complications.

Effect of femoral component offset on polyethylene wear in total hip arthroplasty.

Seventeen staged, bilateral total hip arthroplasties performed in 17 patients were reviewed to compare side-to-side polyethylene wear. Implants used on both sides were similar except for implant offset: one hip in each patient was replaced using a femoral component having a standard implant offset, whereas the other side had a lateral offset implant. The mean followup was 5.70 years (range, 2-10.2 years) on the side with a standard femoral implant and 5.67 years (range, 2-9.7 years) on the side with a lateralized femoral component. The only statistically different parameter between the sides was the femoral component offset. All other parameters affecting polyethylene wear, such as period of followup, head size, head type, cup size, cup inclination, medialization of cup, and patient-related factors were similar on both sides. On the side with a standard femoral component, the mean actual prosthetic offset (determined by manufacturer's specifications) was 35.2 mm and the radiologic offset was 31.5 mm. On the side with a lateralized femoral component, the actual prosthetic offset was 42.5 mm and the radiologic offset was 40.1 mm. The difference in offsets between the sides was statistically significant. The mean preoperative offset of the femur was 38.8 mm. Regression analysis revealed that only femoral component offset and cup size correlated significantly with linear wear rate. On the side with a standard femoral component, the linear wear rate was 0.21 mm per year, whereas on the side with a lateralized femoral component, the linear wear rate was 0.10 mm per year. The differences in the linear wear rates were significant. Lateralization of the femoral component in this series more closely restored preoperative hip biomechanics and significantly decreased polyethylene wear.

Cementless femoral fixation in the rheumatoid patient undergoing total hip arthroplasty: minimum 5-year results.

Sixty-two total hip arthroplasties in 49 patients with a diagnosis of rheumatoid arthritis were performed between November 1986 and December 1992. All components were titanium alloy with a circumferential plasma-spray porous coating. Four patients (4 hips) died before 5-year follow-up, and 6 patients (8 hips) were lost to follow-up, leaving 39 patients (50 hips) for review at a minimum 5-year follow-up after surgery (mean, 8 years; range, 5-12 years). There were 12 men and 27 women, with a mean age at time of surgery of 55 years (range, 25-77 years) and a mean weight of 69 kg (range, 42-109 kg). Compared with the preoperative Charnley scores, there was significant improvement in the postoperative scores: pain, from 2.7 to 5.7, and function, from 3.2 to 5.3. Thigh pain was present in 1 patient (1 hip) (2.0%). No femoral fractures occurred intraoperatively with the insertion of the prosthesis. Spot welds consistent with bone ingrowth were identified in all of the femoral components. No femoral components showed evidence of radiographic loosening or required revision for aseptic loosening or incapacitating thigh pain, but 7 acetabular revisions were performed. Uncemented femoral fixation with this component design in rheumatoid patients appears to be a promising treatment.

Primary cementless total hip arthroplasty in octogenarians. Two to eleven-year follow-up.

BACKGROUND: Cementless total hip arthroplasty is an accepted alternative to total hip arthroplasty with cement in younger patients, but it remains controversial for elderly patients. The purpose of this study was to evaluate the clinical and radiographic outcomes of cementless total hip arthroplasty with use of a proximally coated stem in patients who were at least eighty years of age at the time of the operation. METHODS: One hundred and twenty-three cementless total hip replacements were performed for the treatment of osteoarthritis in 114 patients between the ages of eighty and eighty-nine years. Seven patients (eight hips) died within two years after the surgery, seventeen patients (eighteen hips) died more than two years postoperatively but were not followed for at least two years, and five hips were lost to follow-up; this left ninety-two hips in eighty-six patients for review. The mean duration of follow-up was five years (range, two to eleven years). For the clinical evaluation, the Charnley modification of the Merle d'Aubigné and Postel scale was used. In addition, preoperative and postoperative Harris hip scores were available for sixty-nine hips. Seventy-eight hips were followed radiographically for two years or more. The focus of the radiographic evaluation was the status of the fixation of the femoral and acetabular components as well as cup wear. RESULTS: Perioperative medical complications occurred in association with 24% (thirty) of the 123 operations, but there were no deaths. The mean Charnley scores for pain and function for the ninety-two hips that were followed clinically for at least two years improved by 3.0 and 1.4 points, respectively. The sixty-nine hips for which preoperative and postoperative Harris hip scores were available had a mean improvement of 42 points, with a mean score of 82 points at the last follow-up evaluation. Mild thigh pain was present in four patients, but it did not limit their activity. There were no femoral component revisions. All of the femoral components were radiographically stable and had bone ingrowth. No acetabular component failed by loosening, but 41% (thirty) of the seventy-three hips with radiographs available for measurement of wear showed polyethylene wear. Of the seventy-eight cups that were followed radiographically for two years or more, 4% (three) were associated with lysis, but none had been revised. CONCLUSIONS: Cementless fixation in the elderly is safe, effective, and durable at the time of two to eleven-year follow-up.

Total hip arthroplasty using two different cementless tapered stems.

The authors report their 15-year experience with primary total hip arthroplasty using collarless, tapered, porous-coated femoral stems (Trilock and Taperloc) in patients with osteoarthritis, rheumatoid arthritis, and in octogenarians. Excellent clinical results were achieved in all groups at latest followup. For the patients with Trilock stems, Taperloc stems, and patients who were octogenarians and patients with rheumatoid arthritis, Charnley pain scores were 5.6, 5.5, 5.7, and 5.7; Charnley function scores were 5.2, 5.1, 4.2, and 5.3; Harris hip scores were 92, 92, 82, and 93 points, respectively. There was a 2% rate of thigh pain with the Trilock, 4% with Taperloc, 4% in octogenarians, and 2% in patients with rheumatoid arthritis. In 96% of the patients in the Trilock group, in 100% of the patients in the Taperloc group, in 100% of the patients who were octogenarians, and in 100% of the patients with rheumatoid arthritis, femoral components showed radiographic evidence of bone ingrowth. There were six (12%) femoral component revisions in the Trilock group (all secondary to nonmodularity of the component at the time of acetabular revision), one femoral component revision in the Taperloc group and no femoral component revisions in the patients who were octogenarians or who had rheumatoid arthritis. Design features (collarless tapered wedge fit, circumferentially porous-coated) virtually ensure bone ingrowth and are thought to be responsible for the excellent clinical results and longevity.

Pseudoaneurysm of femoral artery after revision total hip arthroplasty with a constrained cup.

Delayed vascular injury after revision total hip arthroplasty is a rare and unusual complication. We report a case of a mechanical complication in which migration of a constraining ring locking mechanism used during a revision total hip arthroplasty caused a pseudoaneurysm of the common femoral artery.

Routine follow-up office visits after total joint replacement: do asymptomatic patients wish to comply?

A total of 100 patients presenting for routine office follow-up after total hip or knee arthroplasty completed questionnaires evaluating whether they preferred to come to the office for routine follow-up evaluation or whether they would have preferred an evaluation without an office visit. Of 100 patients, 45 would have preferred not to come into the office for a routine evaluation. They were content to mail completed questionnaires and radiographs to their physicians. The other 55 patients preferred office visits. These 2 groups were comparable for age, sex, height, weight, and number of surgeries (P > .11) Preoperative and postoperative scores were similar between the 2 groups (P > .39). None of the patients that would have preferred not to come in to the office believed that quality of care would be compromised. A significant number (45%) of patients would prefer not to come to the office because of the wages saved and time spared. Routine office visits may be eliminated for these patients through the use of health outcome devices, such as the SF-36, along with routine radiographs. The potential to decrease healthcare costs and increase patient satisfaction warrants the identification of these patients. Assessment of the effect on quality of care with elimination of routine follow-up visits requires further study.

Uncemented total hip arthroplasty in Paget's disease of the hip: a report of 5 cases with 5-year follow-up.

Five patients with Paget's disease localized to the acetabulum received cementless acetabular components during total hip replacement. Three were primary surgeries, and 2 were revisions of a failed cemented acetabular component. At an average of 5.8 years (range, 4.8-8.8 years) after the operation, all acetabular components were well fixed radiographically with no migration or loosening. No patients complained of clinical symptoms referable to the acetabular component. No revisions had been performed. The ability of this inherently abnormal bone to proceed through the reparative and remodeling phases of porous ingrowth adds support to the use of uncemented components for acetabular reconstruction in Paget's disease of the hip.

Total hip arthroplasty in patients on long-term renal dialysis.

End-stage renal failure patients on long-term renal dialysis who underwent total hip arthroplasty (THA) were followed. Fifteen hips were implanted in 12 patients. There was a high mortality (58%) and high overall early complication rate (58%) with a deep infection rate of 13%. Of patients, 76% (n = 11) had good clinicoradiologic outcome of the THA before their death or at their latest follow-up. THA in patients on dialysis, however, should be reserved for those among this group who are expected to have a better life expectancy.

Minimum 10-year results of a tapered cementless hip replacement.

Seventy-one total hip arthroplasties with a cementless, wedge fit, cobalt chrome femoral component were reviewed in 60 patients at a minimum 10-year followup (mean, 11.5 years). For the femoral component, the mechanical failure rate was 5% and the revision rate for aseptic loosening was 0%. The mean Charnley scores for pain, function, and motion changed from preoperative mean values of 3.0, 2.7, and 3.2 to followup mean values of 5.7, 5.5, and 5.2, respectively. The followup mean Harris hip Score was 91. The incidence of thigh pain was 1.4% at 10-year followup. Ninety-five percent of femoral components showed radiologic evidence of stable, bone ingrowth fixation, whereas loosening was seen in 5% of stems. Despite the high incidence of acetabular osteolysis, no osteolysis was seen on the femoral side distal to the lesser trochanter. Nonmodularity of the femoral component led to unavoidable revision of stably fixed femoral components in seven (9.8%) hips during the revision of a loose socket. Design features (collarless, tapered, wedge fit, and circumferentially porous coated) were thought to be crucial to the superlative results with the cobalt chrome femoral component.

Factors influencing choice of implants in total hip arthroplasty and total knee arthroplasty: perspectives of surgeons and patients.

To determine the factors influencing surgeons' choice of implants for total hip arthroplasty (THA) and total knee arthroplasty (TKA), 650 surveys were mailed to all active members of the American Association of Hip and Knee Surgeons practicing in the United States; 364 surveys (56%) were completed and returned. Analysis revealed that the average number of total hip and total knee replacements performed by the respondents in 1997 was 81 and 97; there was substantial regional variation. The average number of hip implant and knee implant brands used by these surgeons in 1997 was 2.4 and 1.8. Anticipated improvement in clinical results and cost of components were the most frequently listed reasons for changing brands. Surgeons were also queried about cost reduction programs at their particular institution. The most frequently listed strategies for cost reduction of implants included surgeon cost-awareness programs and volume discounting. More than half of the respondents (53.5%) anticipate manufacturers to decrease the cost of implants in the next 2 years. Most of the respondents (93.7%) currently have the ability to choose a particular implant. About half (46.7%) anticipate losing some or all control of this decision in the next 3 years. These respondents foresee their hospitals requiring the use of a discounted implant in the future. An additional survey was completed by 102 consecutive patients scheduled either for primary THA (64) or primary TKA (38) at our institution. When asked about implant selection, 93.1% responded that their orthopaedic surgeon should choose the prosthesis; 5.9% responded that their physician in consultation with the patient should choose the prosthesis. When asked what should be the primary determinant of implant choice, cost or quality, the overwhelming majority (97.1%) chose quality. A small percentage (2.9%) chose cost and quality. No patient chose cost alone. A large number of patients (84.8%) responded that they would pay additional costs if their insurance companies or health maintenance organizations refused to pay for a better but more expensive implant. Most patients realized how expensive components are, and 51% of the respondents correctly estimated the cost of an implant. Orthopaedic surgeons perceive that they are losing control of implant choice in THA and TKA. Cost of implants is one of the most significant factors influencing which implant is chosen. Patients (the true payors), however, overwhelmingly want their surgeons to choose the implant used at surgery, and they want quality, not cost, to be the primary determinant of this decision.

The impact of personal problems on accessing prenatal care in low-income urban African American women.

OBJECTIVE: The purpose of this study was to investigate the nature and contribution of personal factors related to the use of prenatal care in a sample of high-risk women residing in an urban environment where care was accessible and free. STUDY DESIGN: The sample consisted of 297 African American women with low socioeconomic status and a high school education or less who were newly delivered of neonates. The level of prenatal care was classified according to the Kessner 3 Parameter Index (adequate, intermediate, inadequate). Women who received no prenatal care made up a fourth group. Subjects responded to the "Ten-Item Checklist" of Richwald. Rhodes, and Kersey and an in-person interview that queried their reasons for obtaining different levels of prenatal care. RESULTS: Both personal and structural reasons were described by women for not obtaining care earlier in pregnancy or at all. The mean number of personal and structural problems reported per subject was inversely correlated to the level of prenatal care obtained. However, personal problems were the single most important reason cited by these women. Personal problems that were statistically significant different among the groups were drug use and desire for an abortion. The structural barriers that exhibited statistically significant differences among the groups were trouble scheduling an appointment, access totransportation, dislike of health care professionals and institutions, access to child care, and not knowing where to go. CONCLUSION: Both personal and structural problems were cited as reasons for not obtaining adequate prenatal care. Structural barriers to prenatal care have been identified and extensively studied. These barriers to care continue to persist, despite innovations in program delivery and access. This study demonstrates that the significance of personal problems has not been adequately considered as a major factor associated with insufficient prenatal care.

Conversion of hemiarthroplasty to total hip arthroplasty: can groin pain be eliminated?

In this study 45 patients with groin or buttock pain after hemiarthroplasty were evaluated 2 to 7 years after conversion to total hip arthroplasty. Groin or buttock pain was completely relieved in 36 patients (80%) and partially relieved in an additional 4 patients (9%). After conversion surgery, 9 patients continued to have groin or buttock pain, but no factor could be identified that would predict an unsuccessful result. The hypothesis tested in this study was whether conversion of a hemiarthroplasty to a total hip arthroplasty eliminates groin pain. Because a significant number of patients (up to 20%) will continue to have some groin or buttock pain after conversion surgery, patients should be warned of this contingency before surgery.

Immediate weightbearing after uncemented total hip arthroplasty.

Radiographic subsidence of the femoral prosthesis and clinical results after unilateral and simultaneous bilateral uncemented total hip arthroplasty were compared. Patients who had bilateral total hip arthroplasty began weight-bearing as tolerated on both lower extremities the day after surgery. Patients who had undergone unilateral total hip arthroplasty were maintained at 10% weightbearing on the operative limb for 6 weeks after surgery. Patients in both groups were matched for age, gender, and weight. Minimal followup was 2 years. There was no difference between the two groups in terms of clinical results. Radiographic assessments were performed immediately after surgery, 6 weeks after surgery, and again at 2 years after surgery. Radiographs were reviewed by a single observer and analyzed with a digitized data recorder. Increased subsidence of the femoral prosthesis within the bilateral group was found at 6 weeks. The mean subsidence of the femoral prosthesis at 6 weeks for the bilateral total hip arthroplasty group was 0.86 mm (range, 0.18-2.60 mm) and for the unilateral group was 0.39 mm (range, 0.07-1.46 mm). However, subsidence occurring between 6 weeks and 2 years averaged 0.50 mm (range, 0.09-1.10 mm) for the bilateral group and 0.54 mm (range, 0.03-0.99 mm) for the unilateral group. This difference was not significant. At the 2-year followup, all femoral prostheses in both groups appeared radiographically stable with evidence of bone ingrowth and no indications of loosening. Thus, immediate weightbearing after bilateral total hip arthroplasty in this study resulted in more initial subsidence (during the first 6 weeks after surgery) of the femoral prosthesis but did not preclude the prosthesis from becoming stable and achieving bone ingrowth. Patients in both groups obtained satisfactory clinical results. Because initial stability and bone ingrowth are factors influenced by prosthesis design, the results of this study may not be applicable to all implants.

Relationship of total hip arthroplasty outcomes to other orthopaedic procedures.

The Medical Outcomes Study Short Form-36 was used preoperatively and 2 years postoperatively to compare patients' self reported assessment of health and function between 151 patients who had primary total hip replacement and 49 patients who had total hip revision, 149 patients who had primary total knee replacements, 41 patients who had lumbar laminectomy, and 43 patients who had scoliosis surgery. Primary total hip arthroplasty and lumbar laminectomy posted equivalent followup scores. Primary total hip arthroplasty showed significant improvements in physical function and health perception when compared with revision total hip arthroplasty; all other health parameters were similar. Primary total hip arthroplasty showed significantly better followup scores and greater improvement in scores in four of nine categories of the SF-36 when compared with primary total knee arthroplasty (despite identical scores preoperatively). Despite a higher level of assessed health preoperatively, patients who had scoliosis surgery compared least favorably with patients who had primary total hip arthroplasty at 2 years followup. In terms of patient self assessment of health and function, primary total hip arthroplasty and lumbar laminectomy for radiculopathy gave the best results.

Thiazide-induced hyponatremia in the postoperative total joint replacement patient.

The thiazide diuretic is a common medication in the elderly population for the treatment of hypertension. These same patients are the largest population for surgical intervention for joint arthroplasty. Postoperative management of these patients has shown to be complicated by hyponatremia associated with the use of thiazide diuretics. This study evaluates a consecutive series of 408 patients undergoing elective joint arthroplasty. An association was found with the use of thiazide diuretics in the preoperative period and the development of postoperative hyponatremia. The study is presented, along with a relevant review of the literature and suggestions for the orthopedic staff to limit the risk of hypoantremia and prolonged hospitalization in an otherwise stable postoperative course.

Simultaneous bilateral versus unilateral total knee arthroplasty. Outcomes analysis.

One hundred consecutive, primary simultaneous bilateral total knee arthroplasties were prospectively compared with 100 consecutive, primary unilateral total knee arthroplasties in reference to relative risk, complications, cost, and need for rehabilitation. All procedures were performed using identical preoperative, intraoperative, and postoperative protocols. Postoperative confusion was approximately four times greater in the simultaneous bilateral total knee arthroplasties group (29% versus 7%), which was thought to represent an increased incidence of fat embolism. Cardiopulmonary complications were approximately three times greater after simultaneous bilateral total knee arthroplasties (14% versus 5%), and most commonly involved arrhythmias. The increased stress on the cardiopulmonary system with simultaneous bilateral total knee arthroplasties may make this procedure contraindicated in certain patients with preexisting disease. There was an approximately 17 times greater need for banked blood in the simultaneous bilateral total knee arthroplasties group (17% versus 1%), which is alarming given the persistent concerns of transfusion related disease transmission. Although the length of hospitalization was similar (6.4 days simultaneous bilateral total knee arthroplasties versus 6 days unilateral total knee arthroplasty), 89% of the patients in the simultaneous bilateral total knee arthroplasties group required a rehabilitation stay versus 45% of the patients in the unilateral total knee arthroplasty group. Total hospital charges averaged $53,168 for simultaneous bilateral total knee arthroplasties versus $32,598 for unilateral total knee arthroplasty. Total rehabilitation charges were similar. The relative cost savings implicit by doing simultaneous bilateral total knee arthroplasties seem to be at least partially offset by the approximately two times greater need for rehabilitation in this group. The true safety, efficacy, relative risk, and total cost analysis of simultaneous bilateral total knee arthroplasties demands further critical evaluation.