J. Roderick Davey

Topical Application of Tranexamic Acid Reduces Postoperative Blood Loss in Total Knee Arthroplasty: A Randomized, Controlled Trial

BACKGROUND Topical application of tranexamic acid to bleeding wound surfaces reduces blood loss in patients undergoing some major surgeries, without systemic complications. The objective of the present trial was to assess the efficacy and safety of the topical application of tranexamic acid on postoperative blood loss in patients undergoing primary unilateral total knee arthroplasty with cement. METHODS In a prospective, double-blind, placebo-controlled trial, 124 patients were randomized to receive 1.5 or 3.0 g of tranexamic acid in 100 mL of normal saline solution or an equivalent volume of placebo (normal saline solution) applied into the joint for five minutes at the end of surgery. The primary outcome was blood loss calculated from the difference between the preoperative hemoglobin level and the corresponding lowest postoperative value or hemoglobin level prior to transfusion. The safety outcomes included Doppler ultrasound in all patients and measurement of plasma levels of tranexamic acid one hour after release of the tourniquet. RESULTS Twenty-five patients were withdrawn for various reasons; therefore, ninety-nine patients were included in the intention-to-treat analysis. The postoperative blood loss was reduced in the 1.5 and 3-g tranexamic acid groups (1295 mL [95% confidence interval, 1167 to 1422 mL] and 1208 mL [95% confidence interval, 1078 to 1339 mL], respectively) in comparison with the placebo group (1610 mL [95% confidence interval, 1480 to 1738 mL]) (p < 0.017). The postoperative hemoglobin levels were higher in the 1.5 and 3.0-g tranexamic acid groups (10.0 g/dL [95% confidence interval, 9.5 to 10.4 g/dL] and 10.1 g/dL [95% confidence interval, 9.8 to 10.5 g/dL], respectively) in comparison with the placebo group (8.6 g/dL [95% confidence interval, 8.2 to 9 g/dL]) (p < 0.017). With the numbers studied, there was no difference in the rates of deep-vein thrombosis or pulmonary embolism between the three groups. Minimal systemic absorption of tranexamic acid was observed. CONCLUSIONS At the conclusion of a total knee arthroplasty with cement, topical application of tranexamic acid directly into the surgical wound reduced postoperative bleeding by 20% to 25%, or 300 to 400 mL, resulting in 16% to 17% higher postoperative hemoglobin levels compared with placebo, with no clinically important increase in complications being identified in the treatment groups.

Soft-tissue balancing of the hip: the role of femoral offset restoration.

Inadequate soft-tissue balancing is a major yet often underemphasized cause of failure for primary and revision total hip arthroplasty. Accordingly, contemporary cemented and cementless hip prostheses have been designed with consideration of this issue, and this has substantially increased the long-term survival of total hip replacements. Therefore, it is important for orthopaedic surgeons to be familiar with the rationale, biomechanical principles, and clinical implications associated with soft-tissue balancing of the hip as well as strategies to avoid inadequate soft-tissue balancing and systematic techniques to restore adequate soft-tissue tensioning during total hip arthroplasty.

Predicting Patient Dissatisfaction Following Joint Replacement Surgery

Objective The incidence of patient-reported dissatisfaction following total joint arthroplasty can be up to 30%. Our aim was to identify the preoperative patient-level predictors of patient dissatisfaction 1 year after surgery. Methods We surveyed 1720 patients undergoing primary hip or knee replacement surgery. Relevant covariates including demographic data, body mass index, sex, comorbidities, and education were recorded. Joint functional status and patient quality of life were assessed at baseline and at 1-year followup with the Western Ontario McMaster University Osteoarthritis Index (WOMAC) and Medical Outcomes Study Short Form-36 (SF-36) scales, respectively. Patient satisfaction with surgery was determined with 4 survey questions at 1-year followup. Results There were no significant differences in demographic data between satisfied (n = 1290) and dissatisfied patients (n = 430). Logistic regression modeling showed that a lower preoperative SF-36 Mental Health score independently predicted patient dissatisfaction with surgery, adjusted for all relevant covariates (p < 0.05). We found no correlation between patient satisfaction and WOMAC change scores at 1-year followup (p = 0.31). Conclusion Preoperative mental health is an important factor to consider when understanding patient satisfaction with surgery. Interventions to reduce psychological distress prior to surgery should be studied to determine if they may improve subjective outcomes of patients undergoing joint replacement surgery.

A randomized trial of hydroxyapatite coated prostheses in total hip arthroplasty

In a prospective randomized trial, 62 consecutive primary cementless total hip arthroplasties in 55 patients were performed by one surgeon using either hydroxyapatite coated (35 hips) or nonhydroxyapatite coated femoral prostheses (27 hips). The dual tapered femoral stem had a Ti-6AI-4V plasma sprayed circumferential proximal porous coat applied to the proximal 1/3 of the stem. The middle 1/3 had a roughened blasted textured surface, and the distal 1/3 had a smooth surface. The hydroxyapatite coated femoral stems had an additional hydroxyapatite coating applied to the proximal porous coat with use of an air plasma process. The patients in the two groups were not significantly different regarding age (48.2 +/- 9.0 years hydroxyapatite group, 50.4 +/- 8.7 years control group), gender, Charnley class, or length of followup (4.4 +/- 0.7 years hydroxyapatite group, 4.9 +/- 1.0 years control group). Forty-nine patients (54 hips) were available for clinical followup, and 45 patients (50 hips) had radiographic followup. A minimum 3-year followup was recorded. To date, there have been no femoral prostheses failures. No femoral implant has migrated or subsided. Radiographically, the hydroxyapatite coated stems showed trends toward increased distal stem related cortical hypertrophy, increased cancellous condensation and less endosteal cavitation. Two nonhydroxyapatite coated stems had distal endosteal cavitation, whereas no hydroxyapatite coated stems did. There were two cases of acetabular osteolysis (revision in one) and two cases of acetabular cup migration (nonrevised), all occurring in the control group. The overall revision rate was 4%. There was no difference in Harris hip scores at 6 months (80.6 +/- 13.0 points hydroxyapatite group, 83.8 +/- 12.4 points control group) or at last followup (85.6 +/- 15.4 points hydroxyapatite group, 89.7 +/- 13.4 control group). The Harris hip pain scores also were not significantly different at 6 months or at last followup. Multiple linear regression analysis controlling for age, gender, and length of followup revealed no significant predictors of Harris hip or pain scores. The results of this study at an average of 4.6 years do not indicate a significant clinical advantage to the use of hydroxyapatite coated femoral prostheses in primary cementless total hip arthroplasty when judged by the criteria of Harris hip scores and femoral stem survivorship.

Topical tranexamic acid reduces transfusion rates in total hip and knee arthroplasty.

The efficaciousness of topical tranexamic acid use at the end of knee arthroplasty surgery to reduce blood loss and transfusion requirements has previously been shown. The aim of this study was to retrospectively assess the effectiveness of topical tranexamic acid use, comparing 155 patients undergoing hip and knee arthroplasty surgery in which tranexamic acid was routinely used, to a group of 149 patients from a similar time frame prior to the introduction of tranexamic acid use. The transfusion rate fell from 19.3% to 2.3% for hip arthroplasty patients and from 13.1% to 0% for knee arthroplasty patients; these differences were significant. We also found significant reductions in haemoglobin loss, blood loss and length of stay of 8 g/L, 244 mL and 1.0 days respectively for hip arthroplasties and 15 g/L, 527 mL and 1.2 days respectively for knee arthroplasties following the introduction of tranexamic acid.

Metabolic Syndrome and the Functional Outcomes of Hip and Knee Arthroplasty

Objective. Patients with an elevated systemic inflammatory state are known to report greater pain with knee osteoarthritis (OA). We investigated the influence of risk factors of metabolic syndrome (MetS) on patient function before and after hip and knee replacement surgery. Methods. A total of 677 consecutive patients with primary knee replacement and 547 consecutive patients with primary hip replacement with at least one MetS risk factor were reviewed from our joint registry. Demographic variables of age, sex, and comorbidity were retrieved. MetS risk factors were defined as body mass index (BMI) > 30 kg/m2, diabetes, hypertension, and hypercholesterolemia. Baseline and 1-year Western Ontario McMaster University Osteoarthritis Index (WOMAC) scores were compared across patients by number of MetS risk factors, ranging from 1 to 4. Linear regression modeling was used to evaluate the effects of the MetS risk groups and the individual metabolic abnormalities on predicting baseline and 1-year WOMAC scores. Knee and hip patients were reviewed separately. Results. The knee and hip patients showed a significant difference in sex distribution, BMI, and mean comorbidity across risk groups (p < 0.05). Unadjusted analysis showed that baseline and 1-year WOMAC scores, for both knee and hip patients, increased significantly with increasing number of MetS risk factors (p < 0.05). The linear regression model with the individual metabolic abnormalities was found to be more predictive of outcome than one with the number of MetS risk factors. Hypertension and obesity were the metabolic factors most predictive of a poorer outcome following hip surgery as compared to just obesity for knee patients. Conclusion. Patient function following joint replacement surgery, particularly hip surgery, is negatively affected by metabolic abnormalities perhaps secondary to the systemic proinflammatory state. This knowledge should be used when counseling patients prior to surgery.

A randomized trial of hydroxyapatite-coated femoral stems in total hip arthroplasty: a 13-year follow-up.

A prospective randomized trial comparing hydroxyapatite (HA)-coated and non-HA-coated femoral total hip arthroplasty components was conducted. Sixty-one consecutive patients undergoing primary hip arthroplasty were randomized to receive an identical femoral component with or without HA. Forty-eight hips were available for review at an average of 13 years and 5 months after surgery. The only femoral stem revised was secondary to femoral fracture after mitral valve area. All femoral stems were well fixed on x-ray with no evidence of loosening. There was no statistically significant difference in the revision rates or in the Harris hip score between the HA vs non-HA-coated groups. This study suggests there is no clinical advantage to the use of a hydroxyapatite coating on the femoral component of this design for primary total hip arthroplasty.

Quantifying the pain experience in hip and knee osteoarthritis

PURPOSE The present study investigated whether the conceptualization of hip and knee osteoarthritis pain implicit in the Western Ontario and McMaster Universities Arthritis Index (WOMAC) and Medical Outcomes Study Short-Form 36 (SF-36) scales is complete, or whether the addition of another scale, such as the Short-Form McGill Pain Questionnaire (MPQ-SF), provides a more complete characterization. Furthermore, the impact that mental health symptoms and catastrophizing had on these scales was investigated. METHODS Before hip and knee arthroplasty, 200 patients completed surveys of demographic data, the WOMAC pain scale, the MPQ-SF, the SF-36 Bodily Pain scale, the Pain Catastrophizing Scale and the Hospital Anxiety and Depression Scale. Correlations between scales were calculated and linear regression modelling was used to determine the impact of mental health and catastrophizing on these three pain measures. RESULTS A strong correlation between the WOMAC and SF-36 pain scales (r=-0.70) was found; however, both correlated only moderately with the MPQ-SF (r=0.36 and r=-0.36, respectively). Linear regression modelling showed that the Pain Catastrophizing Scale significantly predicted a greater score on all three pain scales (P<0.05). CONCLUSIONS The addition of the MPQ-SF appears to add to a more complete quantification of the pain experience in hip and knee osteoarthritis.

Metabolic Syndrome and the Incidence of Symptomatic Deep Vein Thrombosis Following Total Knee Arthroplasty

Objective. We asked if patients with metabolic syndrome undergoing total knee replacement (TKR) have an increased risk for symptomatic deep vein thrombosis (DVT) at 3 months followup. Methods. We reviewed 1460 patients from our joint registry undergoing primary, unilateral TKR between 1998–2006. Demographic variables of age, sex, comorbidity, and education were retrieved. Metabolic syndrome was defined as body mass index above 30 kg/m2, diabetes, hypertension, and hypercholesterolemia. Logistic regression was used to examine the relationship of metabolic syndrome on the incidence of DVT. Results. The overall incidence of symptomatic DVT was 4.4% (65/1460). Patients with metabolic syndrome had an increased incidence of DVT compared to those without metabolic syndrome (15.5% vs 3.4%). Adjusted analysis showed that the risk of symptomatic DVT in patients with metabolic syndrome was 3.2 times [odds ratio 3.2, 95% CI (1.0,15.4), p = 0.04] the risk in those without metabolic syndrome. Conclusion. Hospital protocols developed for prophylactic anticoagulation following TKR should give special consideration to patients with metabolic syndrome.

Asian Ethnicity and the Prevalence of Metabolic Syndrome in the Osteoarthritic Total Knee Arthroplasty Population

Metabolic syndrome (MS) is a known risk factor for the development of osteoarthritis (OA). We asked whether the prevalence of MS varies across ethnicity among patients who undergo total knee arthroplasty for end-stage OA. In our population of 1460 patients undergoing primary knee arthroplasty, MS was defined as body mass index greater than 30 kg/m(2), diabetes, hypertension, and hypercholesterolemia. Among the 1334 white patients, 114 (8.5%) had MS as compared with 3 of 36 (8.3%) blacks and 18 of 90 (20%) Asians (P = .006) Adjusted analysis showed that those of Asian ethnicity had a 2.0 (95% confidence interval, 1.1-3.8; P = .03) times greater odds of MS as compared with those of other ethnicity. Metabolic syndrome is a risk factor for OA, and Asians demonstrate a greater prevalence of MS as compared with whites and blacks in this population.