Khalid Syed

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 RESULTS Twenty-five patients were withdrawn for various reasons; therefore, ninety-nine patients were included in the intention-to-treat analysis.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.

Inpatient compared with home-based rehabilitation following primary unilateral total hip or knee replacement: a randomized controlled trial.

BACKGROUND Home-based rehabilitation is increasingly utilized to reduce health-care costs; however, with a shorter hospital stay, the possibility arises for an increase in adverse clinical outcomes. We evaluated the effectiveness and cost of care of home-based compared with inpatient rehabilitation following primary total hip or knee joint replacement. METHODS We randomized 234 patients, using block randomization techniques, to either home-based or inpatient rehabilitation following total joint replacement. All patients followed standardized care pathways and were evaluated, with use of validated outcome measures (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC], Short Form-36, and patient satisfaction), prior to surgery and at three and twelve months following surgery. The primary outcome was the WOMAC function score at three months after surgery. RESULTS The mean length of stay (and standard deviation) in the acute care hospital was 6.3 +/- 2.5 days for the group designated for inpatient rehabilitation prior to transfer to that facility compared with 7.0 +/- 3.0 days for the home-based rehabilitation group prior to discharge home (p = 0.06). The mean length of stay in inpatient rehabilitation was 17.7 +/- 8.6 days. The mean number of postoperative home-based rehabilitation visits was eight. The prevalence of postoperative complications up to twelve months postoperatively was similar in both groups, which each had a 2% rate of dislocation and a 3% rate of clinically important deep venous thrombosis. The prevalence of infection was 0% in the home-based group and 2% in the inpatient group. None of these differences was clinically important. Both groups showed substantial improvements at three and twelve months, with no significant differences between the groups with respect to WOMAC, Short Form-36, or patient satisfaction scores (p > 0.05). The total episode-of-care costs (in Canadian dollars) for the inpatient rehabilitation and home-based rehabilitation arms were

Fatal cardiomyopathy after revision total hip replacement for fracture of a ceramic liner

14,532 and

Relationship between self-reported and performance-based tests in a hip and knee joint replacement population

11,082, respectively (p < 0.01). CONCLUSIONS Despite concerns about early hospital discharge, there was no difference in pain, functional outcomes, or patient satisfaction between the group that received home-based rehabilitation and the group that had inpatient rehabilitation. On the basis of our findings, we recommend the use of a home-based rehabilitation protocol following elective primary total hip or knee replacement as it is the more cost-effective strategy.

Microarray Analysis of the Infrapatellar Fat Pad in Knee Osteoarthritis: Relationship with Joint Inflammation

Symptomatic cobalt toxicity from a failed total hip replacement is a rare but devastating complication. It has been reported following revision of fractured ceramic components, as well as in patients with failed metal-on-metal articulations. Potential clinical findings include fatigue, weakness, hypothyroidism, cardiomyopathy, polycythaemia, visual and hearing impairment, cognitive dysfunction, and neuropathy. We report a case of an otherwise healthy 46-year-old patient, who developed progressively worsening symptoms of cobalt toxicity beginning approximately six months following synovectomy and revision of a fractured ceramic-on-ceramic total hip replacement to a metal-on-polyethylene bearing. The whole blood cobalt levels peaked at 6521 µg/l. The patient died from cobalt-induced cardiomyopathy. Implant retrieval analysis confirmed a loss of 28.3 g mass of the cobalt-chromium femoral head as a result of severe abrasive wear by ceramic particles embedded in the revision polyethylene liner. Autopsy findings were consistent with heavy metal-induced cardiomyopathy.We recommend using new ceramics at revision to minimise the risk of wear-related cobalt toxicity following breakage of ceramic components.

Hip Pain and Heart Failure: The Missing Link

Our objectives were: (1) to assess the relationship between self-reported measures (Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and Medical Outcomes Study Short Form-36 (SF-36)) and a performance-based timed-up-and-go (TUG) test in a hip and knee joint replacement population and (2) to determine the predictors of postoperative functional status as measured by the 12-week WOMAC and TUG scores. We surveyed 200 patients undergoing primary hip or knee replacement surgery for demographic data and outcome scores at baseline and 12-week follow-up. There was a weak correlation between preoperative TUG scores and preoperative SF-36 physical function scores (r = −0.28, p < 0.0001), SF-36 role-physical scores (r = −0.21, p = 0.0022) and WOMAC (r = 0.29, p < 0.0001) scores. The relationship was stronger between the postoperative TUG scores and WOMAC scores (r = 0.43, p < 0.0001), SF-36 physical function scores (r = −0.39, p < 0.0001) and SF-36 role-physical (r = −0.33, p < 0.0001) scores. Significant predictors for the TUG test at 12-week follow-up were age (p = 0.004) and preoperative TUG scores (p < 0.0001). Given low-to-moderate relationship between self-reported and performance-based tools, both tests are needed to assess the true level of patient disability.

The biomechanics of ipsilateral intertrochanteric and femoral shaft fractures: a comparison of 5 fracture fixation techniques.

Objective. To examine differences in genes involved in fat metabolism, energy homeostasis, adipogenesis, and inflammation between endstage and early-stage knee osteoarthritis (OA) infrapatellar fat pads (IFP). Methods. Twenty-nine endstage and 5 early-stage primary OA IFP were harvested at knee surgery. Total RNA was extracted, labeled, and hybridized to whole-genome expression arrays. Unsupervised analysis of all samples using principal components analysis or 2-way hierarchical clustering showed groupings based on tissue source and disease. Statistical testing identified sets of genes that displayed differences between the 2 fat types. Western blot analysis was performed for protein expression of an identified gene of interest. Results. The 29 IFP demonstrated an elevation in the expression of adipokines such as adiponectin and leptin. A statistically significant increased expression was seen for genes of adipogenesis, such as peroxisome proliferator-activated receptor-γ (PPAR-γ), diacylglycerol acyltransferase 2 (DGAT2), cluster of differentiation (CD36), and thyroid hormone responsive spot (THRSP) in the severe OA fat pads as compared to the controls. A subset of 5 patients in the endstage OA group were consistently similar in gene expression to early OA tissue. Protein expression of PPAR-γ2 was 5.4-fold and PPAR-γ1 was 1.4-fold greater in endstage versus early OA tissue. Conclusion. Endstage OA fat pads demonstrated a significant upregulation of genes for fat metabolism and energy homeostasis and a mixed result for inflammatory cytokines.

Relationship between body habitus and joint leptin levels in a knee osteoarthritis population.

A man presented with hypothyroidism, dilated cardiomyopathy, a pericardial effusion, liver failure, and polycythaemia. He had a history of bilateral hip replacements and new-onset hip pain. The patient progressed to develop shock. Given his acutely profound illness and constellation of symptoms, as well as the history of hip replacement, a diagnosis of cobalt toxicity was made.

Antibiotic bone cement and the incidence of deep infection after total knee arthroplasty.

Objectives: The aim of the present study was to examine biomechanically 5 different construct combinations for fixation of ipsilateral intertrochanteric and femoral shaft fractures. Methods: Twenty-five fresh-frozen adult human femora (age range = 58-91 years, average age = 75.4 years) were tested in physiological bending and in torsion to characterize initial bending and torsional stiffness and stiffness following fixation of combined intertrochanteric and femoral shaft fractures. Five fracture fixation device constructs were assessed-construct A: long dynamic hip screw (long DHS); construct B: reconstruction nail; construct C: DHS plus low-contact dynamic compression plate; construct D: DHS plus retrograde intramedullary nail; and construct E: long intramedullary hip screw. Axial stiffness, torsional stiffness, and axial load-to-failure were the main measurements recorded. Results: There were no differences between constructs in terms of axial stiffness (P = 0.41), external rotation stiffness (P = 0.13), and axial load-to-failure (P = 0.16). However, there was a borderline statistically significant difference in internal rotation stiffness between the constructs (P = 0.048). Specifically, construct C was significantly stiffer than construct E (P = 0.04). Conclusions: All constructs showed no statistical differences when compared with one another, with the exception of construct E, which provided the least torsional stiffness. However, the current in vitro model did not simulate fracture healing or support offered by soft tissues, both of which would affect the stiffness and load-to-failure levels reached.

Systemic cobalt toxicity from total hip arthroplasties: review of a rare condition Part 1 - history, mechanism, measurements, and pathophysiology.

Synovial fluid (SF) leptin has been shown to have an association with cartilage degeneration. Our objective was to examine the relationship between different measures of body habitus and SF leptin levels in an end‐stage knee osteoarthritis (OA) population. Sixty consecutive patients with knee OA were surveyed prior to surgery for demographic data. Body habitus was assessed with the body mass index (BMI), waist circumference (WC), and waist–hip ratio (WHR). SF and serum samples were analyzed for leptin and adiponectin using specific ELISA. Nonparametric correlations and linear regression modeling was used to identify the relationship between the measures of body habitus and SF leptin levels. Females had greater levels of leptin than males in both the serum and SF. Significant correlations were found between SF leptin levels and BMI and WC (R2 0.44 and 0.38, respectively; p < 0.05). Regression modeling showed that female gender and WC were independent predictors of a greater SF leptin level independent of age, BMI, and presence of diabetes (p < 0.05). WC may be a more accurate measure of body habitus than BMI in the relationship between the metabolic effects of adipose tissue and OA.