Preoperative Acute Inflammatory Markers as Predictors for Postoperative Complications in Primary Total Knee Arthroplasty.

BACKGROUND: C-reactive protein (CRP) has been suggested as an independent risk factor for cardiovascular pathology in the nonsurgical setting. While postoperative CRP and erythrocyte sedimentation rate (ESR) have an established role in aiding the diagnosis of periprosthetic joint infections, some authors suggest a link between preoperative CRP and postoperative complications in patients undergoing total joint arthroplasty. METHODS: We conducted a retrospective cohort study of 351 patients who underwent unilateral primary total knee arthroplasty by a single surgeon during a 28-month period (January 2013 through April 2015). Patient medical records were reviewed for the following complications occurring within 90 days postoperatively: myocardial infarction, arrhythmia, pulmonary embolism, wound infection, acute renal failure, and reoperation. RESULTS: We found no statistically significant link between postoperative complications and preoperative CRP levels (P=0.5005) or ESR levels (P=0.1610). CONCLUSION: The results of this study do not support the routine inclusion of CRP and ESR analysis as part of the preoperative evaluation for elective total knee arthroplasty.

Risk stratified usage of antibiotic-loaded bone cement for primary total knee arthroplasty: short term infection outcomes with a standardized cement protocol.

Efficacy of antibiotic cement (ALBC) in primary knee arthroplasty (pTKA) has been debated. The study's purpose was to examine efficacy of ALBC versus plain cement (PBC) in preventing infection in high-risk patients undergoing pTKA. 3292 consecutive pTKAs were divided into three cohorts: (1) patients receiving only PBC, (2) patients receiving only ALBC, and (3) only high-risk patients receiving ALBC. Cohorts' infections were compared. The 30-day infection rates for cohorts 1, 2, 3 were 0.29%, 0.20%, and 0.13% respectively. 6-month rates were 0.39%, 0.54% and 0.38%. 1-year rates were 0.78%, 0.61%, and 0.64%. Differences in infection rates at all time intervals were not statistically significant. The study supports that even judicious risk-stratified usage of ALBC may not confer added benefit in decreasing infection at one year.

Establishing a role for vancomycin powder application for prosthetic joint infection prevention-results of a wear simulation study.

Topical vancomycin powder (VP) has shown efficacy and safety in decreasing post-operative spine infections. VP use in arthroplasty has not been established. Concerns remain for third-body wear with the addition of crystalline substrate at the implant interface. The study's purpose was to compare wear behavior of CoCr on UHMWPE to identical wear couples with VP. A six-station wear simulator was utilized and cyclic articulations were run for 10 million cycles (Mc). UHMWPE wear was measured using photography, stereomicroscopy, and gravimetric measurement. There were no differences in wear mark length (P = 0.43), width (P = 0.49), or gravimetric wear at 10 Mc (P = 0.98). VP and control groups lost 0.32 and 0.33 mg, respectively. VP may have a role in PJI prevention. A well-designed clinical study is needed.

An evaluation of the use of topical tranexamic acid in total knee arthroplasty.

The purpose of this study was to evaluate the effectiveness of topical tranexamic acid in primary TKA from a clinical and economic standpoint. We retrospectively reviewed 683 primary total knee arthroplasties performed at a single institution over a 2-year period. We compared 373 cases performed in 2010 without tranexamic acid to 310 cases performed in 2011 with tranexamic acid. Demographic data, hemoglobin levels, transfusion rates, hospital length of stay, cost, and perioperative complications during the first 3 months were collected. Statistical analysis was performed using two sample t-tests and Fisher's exact tests. There was no difference in age, sex, height, or pre-operative hemoglobin between the two groups. The tranexamic acid group had significantly higher post-operative hemoglobin (P<0.0001), lower transfusion rate (P<0.0001), decreased length of stay (P<0.0001), decreased blood bank costs (P<0.0001), increased pharmacy cost (P<0.0001), and decreased total direct cost to the hospital (P<0.0001). The average savings was approximately $1500 per patient. There were no differences in thromboembolic events or infection. The use topical tranexamic acid in primary TKA is safe, effective, and results in significant cost savings.

The effects of MK-0677, an oral growth hormone secretagogue, in patients with hip fracture.

OBJECTIVES: To evaluate the effects of MK-0677, an orally active growth hormone (GH) secretagogue, on functional recovery from hip fracture in previously mobile older individuals. DESIGN: Placebo-controlled, randomized, double-blind trial. SETTING: Thirteen medical centers in England, Sweden, Denmark, Belgium, Switzerland, Canada, and the United States. Patients were recruited between 3 and 14 days postoperatively, or no more than 18 days postfracture, at acute care hospitals and rehabilitation centers. PARTICIPANTS: One hundred sixty-one hip-fracture patients were enrolled. Entry criteria included consenting hip-fracture patients who were aged 65 and older and who were ambulatory before their fracture, medically stable postoperatively, and mentally competent. Patients were excluded if they had multiple fractures or severe trauma, diabetes mellitus, cancer, uncontrolled hypertension, congestive heart failure, or total hip replacement in the involved extremity. INTERVENTION: Random assignment to 6 months of daily treatment with MK-0677 or placebo. Patients were followed for an additional 6 months after completion of therapy. MEASUREMENTS: Change from Week 6 to Week 26 in a panel of functional performance measures. Additional outcome measures included change in the Sickness Impact Profile for Nursing Homes (SIP-NH), the ability to live independently, and insulin-like growth factor I (IGF-I) levels. RESULTS: MK-0677 treatment increased serum IGF-I levels by 84% (95% confidence interval (CI)=63-107), compared with an increase of 17% (95% CI=8-28) on placebo. There were no significant differences between MK-0677 and placebo in improvement in functional performance measures or in the overall SIP-NH score. Although MK-0677 patients showed greater improvement relative to placebo in three of four lower extremity functional performance measures, in the physical domain of the SIP, and in the ability to live independently, these differences were not statistically significant. CONCLUSION: Although MK-0677 treatment increased serum IGF-I, it is uncertain whether clinically significant effects on physical function were achieved. Measuring function in clinical trials in hip-fracture patients is difficult because of the lack of validated outcome measures, high variability, and the lack of a baseline assessment. Present functional performance measures may not be sufficiently responsive for use as the primary endpoint of small intervention studies; alternatively, stimulation of GH may not result in significant functional improvement.