Infection of the surgical site after arthroplasty of the hip

A Novel Biofilm-Disrupting Wound Care Technology for the Prevention of Surgical Site Infections Following Total Joint Arthroplasty: A Conceptual Review

Surgical site infections (SSIs) are a major driver for increased costs following lower extremity joint arthroplasty procedures. It has been estimated that these account for over $2 billion in annual costs in the United States. While many of the current strategies for the prevention and treatment of SSIs target planktonic bacteria, 80 to 90% of bacterial pathogens exist in a sessile state. These sessile bacteria can produce extracellular polymeric substance (EPS) as protective barriers from host immune defenses and antimicrobial agents and thus, can be exceedingly difficult to eradicate. A novel wound care gel that disrupts the EPS and destroys the inciting pathogens has been developed for the treatment and prevention of biofilm-related infections. This is achieved by the simultaneous action of four key ingredients: (1) citric acid; (2) sodium citrate; (3) benzalkonium chloride; and (4) polyethylene glycol. Together, these constituents create a high osmolarity, pH-controlled environment that deconstructs and prevents biofilm formation, while destroying pathogens and promoting a moist environment for optimal wound healing. The available clinical evidence demonstrating the efficacy of this technology has been summarized, as well as the economic implications of its implementation and the authors' preferred method of its use. Due to the multifaceted burden associated with biofilm-producing bacteria in arthroplasty patients, this technology may prove to be beneficial for patients who have higher risks for infection, or perhaps, as a prophylactic measure to prevent infections for all patients.

Prolonged antibiotic prophylaxis use in elective orthopaedic surgery - a cross-sectional analysis

Purpose

Surgical antibiotic prophylaxis (SAP) prevents surgical site infections (SSI). In orthopaedic surgery, the use of prolonged SAP (PSAP) has been reported in daily routine, despite guidelines advising against it. Therefore, we asked: What is the proportion of PSAP use, defined as administration of SAP ≥24 h after elective orthopaedic surgery? Are there patient- and surgery-related predictors of PSAP use?

Methods

This cross-sectional analysis investigated 1292 patients who underwent elective orthopaedic surgery including total joint arthroplasties at one Swiss centre between 2015 and 2017. Patient comorbidities, surgical characteristics and occurrence of SSI at 90 days in PSAP group were compared to the SAP group (< 24 h post-operative).

Results

PSAP use was 12% (155 of 1292). Patient-related factors associated with PSAP compared to the SAP group included older age (63 vs. 58y; p < 0.001), higher BMI (29 vs. 27 kg/m²; p < 0.001), ASA classification ≥3 (31% vs. 17%; p < 0.001) and lung disease (17% vs. 9%; p = 0.002). Surgery-related factors associated with PSAP were use of prosthetics (62% vs. 45%; p < 0.001), surgery of the knee (65% vs. 25%; p < 0.001), longer surgery duration (87 vs. 68 min; p < 0.001) and presence of drains (90% vs. 65%; p < 0.001). All four SSI occurred in the SAP group (0 vs. 4; p = 1.0). Surgeons administered PSAP with varying frequencies; proportions ranged from 0 to 33%.

Conclusion

PSAP use and SSI proportions were lower than reported in the literature. Several patient- and surgery-related factors associated with PSAP use were identified and some were potentially modifiable. Also, experienced surgeons seemed to implement differing approaches regarding the duration of SAP administration.

Predictors of wound leakage in patients undergoing surgery for neck of femur fractures

AIMS

Persistent wound leakage following joint arthroplasty is a known risk for periprosthetic joint infection. Little is known of the predictors of wound leakage, particularly in patients with a fractured neck of femur. We aimed to determine patient and surgical risk factors for wound leakage in this cohort.

MATERIALS AND METHODS

All patients undergoing surgery for a fractured neck of femur at Leicester Royal Infirmary between May and August 2017 were included. Patients were identified from a prospective database and placed into two groups: those with wound leakage later than three days postoperatively and those without leakage. All previously reported potential risk factors for wound leakage were compared between groups using a chi-square test and logistic regression. A Kattan-style nomogram was also created to allow probabilities output for the regression predictive models in a visual representation.

RESULTS

Two hundred patients underwent surgery for a fractured neck of femur. Overall, 17% of patients (33/200) developed a persistent leaky wound. A multivariable model highlighted increased age (p = 0.01), raised body mass index (BMI; > 25 kg/m²; p = 0.047), diabetes (p = 0.03) and intramedullary hip screw fixation (p = 0.03) as significant risk factors for wound leakage. Patients with persistent wound leakage had significantly longer hospital admission than those without (p = 0.001).

DISCUSSION

Our analysis identified four perioperative risk factors for wound leakage following fractured neck of femur surgery. We also developed a novel tool to identify those patients at highest risk of leakage. Once identified, the aggressive management of certain medical comorbidities in these patients may help to reduce their incidence of wound issues and the prolonged admissions that result.

Efficacy of two integrated geriatric care pathways for the treatment of hip fractures: a cross-cultural comparison

INTRODUCTION

Many studies have focussed on the implementation and outcomes of geriatric care pathways (GCPs); however, little is known about the possible impact of clinical practices on these pathways. A comparison was made between two traumageriatric care models, one Swiss (CH) and one Dutch (NL), to assess whether these models would perform similarly despite the possible differences in local clinical practices.

MATERIALS AND METHODS

This cohort study included all patients aged 70 years or older with a unilateral hip fracture who underwent surgery in 2014 and 2015. The primary outcomes were mortality and complications. Secondary outcomes were time to surgical intervention, hospital length of stay (HLOS), differences in surgical treatment and the number of patients who needed secondary surgical intervention.

RESULTS

A total of 752 patients were included. No differences were seen in mortality at 30 days, 90 days and 1 year post-operatively. In CH, fewer patients had a complicated course (43.5% vs. 51.3%; p = 0.048) and fewer patients were diagnosed with delirium (7.9% vs. 18.3%; p < 0.01). More myocardial infarctions (3.8% vs. 0.4%; p < 0.01) and red blood cell transfusions (27.2% vs. 13.3%; p < 0.01) were observed in CH and HLOS in CH was longer (Mdn difference: - 2; 95% CI - 3 to - 2). Furthermore, a difference in anaesthetic technique was found, CH performed more open reductions and augmentations than NL and surgeons in CH operated more often during out-of-office hours. Also, surgery time was significantly longer in CH (Mdn difference: - 62; 95% CI - 67 to - 58). No differences were seen in the number of patients who needed secondary surgical interventions.

CONCLUSIONS

This cross-cultural comparison of GCPs for geriatric hip fracture patients showed that quality of care in terms of mortality was equal. The difference in complicated course was mainly caused by a difference in delirium diagnosis. Differences were seen in surgical techniques, operation duration and timing. These clinical practices did not influence the outcome.

Chitosan and Hydroxyapatite Based Biomaterials to Circumvent Periprosthetic Joint Infections

Every year, worldwide, millions of people suffering from joint pain undergo joint replacement. For most patients, joint arthroplasty reduces pain and improve function, though a small fraction will experience implant failure. One of the main reasons includes prosthetic joint infection (PJI), involving the prosthesis and adjacent tissues. Few microorganisms (MO) are required to inoculate the implant, resulting in the formation of a biofilm on its surface. Standard treatment includes not only removal of the infected prosthesis but also the elimination of necrotic bone fragments, local and/or systemic administration of antibiotics, and revision arthroplasty with a new prosthesis, immediately after the infection is cleared. Therefore, an alternative to the conventional therapeutics would be the incorporation of natural antimicrobial compounds into the prosthesis. Chitosan (Ch) is a potential valuable biomaterial presenting properties such as biocompatibility, biodegradability, low immunogenicity, wound healing ability, antimicrobial activity, and anti-inflammatory potential. Regarding its antimicrobial activity, Gram-negative and Gram-positive bacteria, as well as fungi are highly susceptible to chitosan. Calcium phosphate (CaP)-based materials are commonly utilized in orthopedic and dentistry for their excellent biocompatibility and bioactivity, particularly in the establishment of cohesive bone bonding that yields effective and rapid osteointegration. At present, the majority of CaP-based materials are synthetic, which conducts to the depletion of the natural resources of phosphorous in the future due to the extensive use of phosphate. CaP in the form of hydroxyapatite (HAp) may be extracted from natural sources as fish bones or scales, which are by-products of the fish food industry. Thus, this review aims to enlighten the fundamental characteristics of Ch and HAp biomaterials which makes them attractive to PJI prevention and bone regeneration, summarizing relevant studies with these biomaterials to the field.

Perioperative Complications after Parotidectomy Using a Standardized Grading Scale Classification System

Perioperative complications after parotidectomy are poorly studied and have a potential impact on hospitalization stay. The Clavien–Dindo classification of postoperative complications used in visceral surgery allows a recording of all complications, including a grading scale related to the severity of complication. The cohort analyzed for perioperative complications is composed of 436 parotidectomies classified into three types, four groups, and three classes, depending on extent of parotid resection, inclusion of additional procedures, and pathology, respectively. Using the Clavien–Dindo classification, complications were reported in 77% of the interventions. In 438 complications, 430 (98.2%) were classified as minor (332 grade I and 98 grade II), and 8 (1.8%) were classified as major (grade III). Independent variables affecting the risk of perioperative complications were duration of surgery (odds ratio = 1.007, p-value = 0.029) and extent of parotidectomy (odds ratio = 4.043, p-value = 0.007). Total/subtotal parotidectomy was associated with an increased risk of grade II-III complications (odds ratio = 2.866 (95% CI: 1.307–6.283), p-value = 0.009). Median hospital stay increased moderately in patients with complications. Use of Clavien–Dindo classification shows that parotidectomy is followed by a higher rate of perioperative complications than usually reported. Almost all complications are minor and have limited consequence on hospital stay.

Can Pediatric Orthopaedic Surgery be Done Safely in a Freestanding Ambulatory Surgery Center? Review of 3780 Cases

BACKGROUND

The purpose of this study was to determine the intraoperative and 30-day postoperative complication rates in a large consecutive cohort of pediatric patients who had orthopaedic surgery at a freestanding ambulatory surgery center (ASC). The authors also wanted to identify the rates of same-day, urgent hospital transfers, and 30-day hospital admissions. The authors hypothesized that pediatric orthopaedic procedures at a freestanding ASC can be done safely with a low rate of complications.

METHODS

A retrospective review identified patients aged 17 years or younger who had surgery at a freestanding ASC over a 9-year period. Adverse outcomes were divided into intraoperative complications, postoperative complications, need for the secondary procedure, unexpected hospital admission on the same day of the procedure, and unexpected hospital admission within 30 days of the index procedure. Complications were graded as grade 1, the complication could be treated without additional surgery or hospitalization; grade 2, the complication resulted in an unplanned return to the operating room (OR) or hospital admission; or grade 3, the complication resulted in an unplanned return to the OR or hospitalization with a change in the overall treatment plan.

RESULTS

Adequate follow-up was available for 3780 (86.1%) surgical procedures. Overall, there were 9 (0.24%) intraoperative complications, 2 (0.08%) urgent hospital transfers, 114 (3%) complications, and 16 (0.42%) readmissions. Seven of the 9 intraoperative complications resolved before leaving the OR, and 2 required return to the OR.Neither complications nor hospitalizations correlated with age, race, gender, or length or type of surgery. There was no correlation between the presence of medical comorbidities, body mass index, or American Society of Anesthesiologists score and complication or hospitalization.

CONCLUSIONS

Pediatric orthopaedic surgical procedures can be performed safely in an ASC because of multiple factors that include dedicated surgical teams, single-purpose ORs, and strict preoperative screening criteria. The rates of an emergency hospital transfer, surgical complications, and 30-day readmission, even by stringent criteria, are lower than those reported for outpatient procedures performed in the hospital setting.

LEVEL OF EVIDENCE

Level IV-case series.

Unicompartmental knee arthroplasty is associated with lower proportions of surgical site infection compared with total knee arthroplasty: A retrospective nationwide database study

BACKGROUND

This study aimed to clarify the association between types of knee arthroplasty (KA) (total knee arthroplasty (TKA) or unicompatmental knee arthroplasty (UKA)) and surgical site infection (SSI) with adjustment for various factors, using a Japanese national database.

METHODS

Data on 181,608 patients who underwent unilateral primary KA for osteoarthritis from 2010 to 2017 were obtained from the Japanese Diagnosis Procedure Combination database. SSI was identified based on International Classification of Diseases 10th Revision codes. Deep SSI (i.e. periprosthetic joint infection (PJI)) was identified as SSI treated with surgical procedures. Multivariable logistic regression analyses for SSI and PJI were performed, in which dependent variables included types of KA, patient backgrounds (sex, age, body mass index (BMI), smoking status, comorbidities), and seasonality.

RESULTS

Eight percent of analyzed patients underwent UKA, while 92% underwent TKA. The proportions of SSI and PJI after UKA were 0.9% and 0.3%, respectively, both of which were lower than those after TKA (1.9% and 0.6%) (P < 0.001). Multivariable analyses showed lower proportions of SSI for UKA (adjusted odds ratio, 0.47; 95% confidence interval, 0.37-0.60; P < 0.001) and PJI (adjusted odds ratio, 0.47; 95% confidence interval, 0.34-0.65; P < 0.001) than TKA. Other factors associated with both SSI and PJI included male sex, BMI >30 kg/m², renal dysfunction and summer season.

CONCLUSION

UKA was associated with lower proportions of SSI and PJI than TKA. Surgeons should carefully consider the indication of UKA before performing TKA, especially in patients with knee unicompartmental osteoarthritis who are at a high risk for SSI or PJI.

Use of barbed suture in total hip prosthesis. Prospective randomized study

INTRODUCTION

The correct closure of the surgical wound is an important step in the procedure of a total hip prosthesis implantation (total hip arthroplasty, THA), which aims to a correct healing of the wound and minimize the risk of complications. The objective of our study is to determine if the use of a bidirectional barbed suture decreases the closing time after THA, in the fascial and subcutaneous plane, when compared to the conventional suture polyglactin 910. The hypothesis is that there is no difference in closing time when comparing both sutures.

MATERIAL AND METHOD

Prospective single blind randomized study comparing two groups: study group with the use of bidirectional continuous barbed suture (Quill™) (Gr. Q) and a control group (Gr. V) using discontinuous polyglactin 91 suture (Vicryl™). Closure was performed in two planes (fascial and subcutaneous) simultaneously by two surgeons. The exclusion criteria were: previous surgeries on the same hip, revision surgeries, major deformities and allergies to suture components. The variables under study were: 1) fascia closure time, subcutaneous and global; 2) surgical wound infection; and 3) dehiscence.

RESULTS

82 patients (39 Gr. Q, 43 Gr. V) were included. The global closing time was shorter in Gr. Q (5 min 59 sec) compared to Gr. V (7.01 min), (p < 0.04). They showed differences in subcutaneous closure: Gr. Q shorter time with a 37 seconds difference (p = 0.048). Differences in fascial plane were not observed. Superficial infection was observed in one Gr. Q patient and another in Gr. V; one case of deep infection in Gr. Q (p = 0.29). One patient presented dehiscence of the wound in Gr. Q (p = 0.3). However, these differences did not show statistical significance.

CONCLUSIONS

The use of a barbed suture allows a shorter closing time compared to the conventional one. However, despite this decrease in time, no differences were found in terms of the appearance of infection or wound dehiscence.

Surgical site infection in hip arthroplasty in a 10-year follow-up prospective study: Risk and factors associated

BACKGROUND

The increased demand for hip arthroplasty means a growing number of postsurgical complications. This study aims to assess the risk of surgical site infection (SSI) in a teaching hospital; develop regional, national and international external comparisons; and evaluate SSI-related risk factors, particularly according to the timing of surgery (urgent/unplanned or elective).

METHODS

Prospective cohort study from January 2008 to December 2018. Patients were followed up to 90 days after surgery. Primary endpoint was SSI incidence according to the Centers for Disease Control and Prevention criteria. Multivariate analysis was conducted to find independently associated SSI risk factors. The association between risk factors and SSI incidence was assessed by reference to odds ratio (OR). Analyses were also performed among urgent/unplanned and elective patients to identify whether SSI risk factors differed between groups.

RESULTS

The study population (n = 1,808) has an overall SSI rate of 3.0% (95% confidence interval [CI]: 2.4-3.9). Timing of surgery caused an effect modification, so surgery duration> 75th percentile (OR: 3.8; 95% CI: 1.5-9.8) and inadequate preparation (OR: 3.3; 95% CI: 1.1-10.0) were independent risk factors in the urgent/unplanned group; National Healthcare Safety Network risk index≥ 2 (OR: 6.3; 95% CI: 0.1-19.2) and transfusion (OR: 3.6; 95% CI: 1.1-11.9) in the elective group.

CONCLUSIONS

Hospital infection surveillance systems allow identifying risk factors susceptible to change. Characterization of factors that caused an effect modification is key to identify areas of quality improvement, including reducing operating times, preventing perioperative blood transfusion, or improving patient preparation before surgery.

A Six-Year Point Prevalence Survey of Healthcare-Associated Infections in an Italian Teaching Acute Care Hospital

Healthcare-associated infections (HAI) represent one of the most common cause of infection and an important burden of disease. The aim of this study was to analyze the results of a six-year HAI point prevalence survey carried out yearly in a teaching acute care hospital from 2013 to 2018, following the European Center for Disease Prevention and Control (ECDC) guidelines. Surgical site infections, urinary tract infections, bloodstream infections, pneumonia, meningitis, and Clostridium difficile infections were considered as risk factors. A total of 328 patients with HAI were detected during the 6-year survey, with an average point prevalence of 5.24% (95% CI: 4.70-5.83%). Respiratory tract infections were the most common, followed by surgical site infections, urinary tract infections, primary bloodstream infections, Clostridium difficile infections, and central nervous system infections. A regression model showed length of stay at the moment of HAI detection, urinary catheter, central venous catheter, and antibiotic therapy to be the most important predictors of HAI prevalence, yielding a significant adjusted coefficient of determination (adjusted R2) of 0.2780. This will provide future infection control programs with specific HAI to focus on in order to introduce a proper prophylaxis and to limit exposure whenever possible.

Association between Hemiarthroplasty vs Total Hip Arthroplasty and Major Surgical Complications among Patients with Femoral Neck Fracture

Previous studies have shown better clinical outcomes after total hip arthroplasty (THA) compared to hemiarthroplasty (HA) for displaced femoral neck fracture. However, few studies have focused on the surgical risks of the two procedures. Therefore, we investigated the perioperative complications of HA and THA in femoral neck fracture, using a large nationwide inpatient database. A total of 286,269 patients (281,140 patients with HA and 5129 with THA) with a mean age of 81.7 were enrolled and HA and THA patients were matched by a propensity score to adjust for patient and hospital characteristics. Patients in a matched cohort were analyzed to compare complications and mortality. The systemic complication rate was not significantly different after a propensity score matching of 4967 pairs of patients. However, the incidence of both hip dislocation and revision surgery was more frequent in the THA group (Risk difference (RD), 2.74; 95% Confidence interval (CI), 2.21–3.27; p < 0.001; RD, 2.82; 95% CI, 2.27–3.37; p < 0.001, respectively). There was no significant difference in 30 day in-hospital mortality among the two groups. The risk of dislocation and reoperation was higher for THA than for HA in elderly patients with a femoral neck fracture in this retrospective study using a nationwide database.

Complications to 6 months following total hip or knee arthroplasty: observations from an Australian clinical outcomes registry

Background

Total hip and total knee arthroplasty (THA/TKA) are increasing in incidence annually. While these procedures are effective in improving pain and function, there is a risk of complications.

Methods

Using data from an arthroplasty registry, we described complication rates including reasons for reoperation and readmission from the acute period to six months following THA and TKA in an Australian context. Data collection at 6 months was conducted via telephone interview, and included patient-reported complications such as joint stiffness, swelling and paraesthesia. We used logistic regression to identify risk factors for complications.

Results

In the 8444 procedures included for analysis, major complications were reported by 9.5 and 14.4% of THA and TKA patients, respectively, whilst minor complications were reported by 34.0 and 46.6% of THA and TKA patients, respectively. Overall complications rates were 39.7 and 53.6% for THA and TKA patients, respectively. In THA patients, factors associated with increased risk for complications included increased BMI, previous THA and bilateral surgery, whereas in TKA patient factors were heart disease, neurological disease, and pre-operative back pain and arthritis in a separate joint. Female gender and previous TKA were identified as protective factors for minor complications in TKA patients.

Conclusion

We found moderate rates of major and high rates of minor postoperative complications following THA and TKA in Australia and have identified several patient factors associated with these complications. Efforts should be focused on identifying patients with higher risk and optimising pre- and post-operative care to reduce the rates of these complications.

Associations between ASA classification, self-estimated physical health, psychological wellbeing and anxiety among Swedish orthopaedic patients

BACKGROUND

The evaluation of one's physical health and psychological wellbeing may be subjective. Aspects of functional capacity, including the patients' own estimation of physical health and wellbeing, have been shown to be strong predictors of postoperative outcomes and should be the focus of further research.

AIM

This study aimed to explore the associations between ASA classification, self-estimated physical health, psychological wellbeing and anxiety among orthopaedic patients.

METHODS

This was a longitudinal study using a quantitative approach.

SETTINGS

A central county hospital in northern Sweden.

RESULTS

A high ASA classification rated by anaesthetists was not associated with physical health and psychological wellbeing self-estimated as less than good. A high ASA classification was significantly associated with self-estimated anxiety prior to surgery. Three days and one month post-surgery, the situation was reversed, and the ASA I/II group, to a significantly higher extent, rated that they felt anxiety.

CONCLUSION

Preoperative screening systems for orthopaedic patients should not only focus on the medical and objective physical issues but also include the patients' own estimation of their physical health and psychological wellbeing. It is essential that orthopaedic patients receive relevant information that provides a realistic outlook, as well as an honest and optimistic future view.

Operative time greater than 120 minutes is associated with increased pulmonary and thromboembolic complications following revision total hip arthroplasty

BACKGROUND

The aim of this study was to determine the impact of operative time on the development of early postoperative complications in patients undergoing revision total hip arthroplasty (THA).

METHODS

In this retrospective cohort study, data were collected through the American College of Surgeons National Quality Improvement Program Database. All patients who underwent revision THA between 2007 and 2016 were identified and stratified into groups based on operative time|: 0-60 min, 61-120 min, 121-180 min, and > 180 min. The incidence of early postoperative adverse events with 30 days, including cardiac, pulmonary, renal, septic, thromboembolic, urinary tract, and wound complications, death, length of stay > 7 days, and unplanned return to the operating room were collected. The complications rates following revision THA were evaluated with univariate and multivariate analyses with significance set at p < 0.05.

RESULTS

A total of 6271 revision THA patients were included for analysis. Patients who had > 120 min of operative time had a significantly increased risk of the development of pulmonary (OR: 1.339; 95% CI: 1.08-1.661; p = 0.008) and thromboembolic complications (OR: 1.34; 95% CI: 1.053-1.707; p = 0.017) and also had an extended length of stay greater than 7 days (OR: 1.413; 95% CI: 1.295-1.541; p < 0.001).

CONCLUSIONS

Increased operative time (> 120 min) during revision THA is associated with increased risk of pulmonary and thromboembolic complications, and prolonged hospitalizations (greater than seven days).

Total cost of surgical site infection in the two years following primary knee replacement surgery

Objective:

The disease burden of surgical site infection (SSI) following total knee (TKA) replacement is considerable and is expected to grow with increased demand for the procedure. Diagnosing and treating SSI utilizes both inpatient and outpatient services, and the timing of diagnosis can affect health service requirements. The purpose of this study was to estimate the health system costs of infection and to compare them across time-to-diagnosis categories.

Methods:

Administrative data from 2005–2016 were used to identify cases diagnosed with SSI up to 1 year following primary TKA. Uninfected controls were selected matched on age, sex and comorbidities. Costs and utilization were measured over the 2-year period following surgery using hospital and out-of-hospital data. Costs and utilization were compared for those diagnosed within 30, 90, 180, and 365 days. A subsample of cases and controls without comorbidities were also compared.

Results:

We identified 238 SSI cases over the study period. On average, SSI cases cost 8 times more than noninfected controls over the 2-year follow-up period (CaD$41,938 [US$29,965] vs CaD$5,158 [US$3,685]) for a net difference of CaD$36,780 (US$26,279). The case-to-control ratio for costs was lowest for those diagnosed within 30 days compared to those diagnosed later. When only patients without comorbidities were included, costs were >7 times higher.

Conclusion:

Our results suggest that considerable costs result from SSI following TKA and that those costs vary depending on the time of diagnosis. A 2-year follow-up period provided a more complete estimate of cost and utilization.

Surgical automation reduces operating time while maintaining accuracy for direct anterior total hip arthroplasty

Objective

Investigate the efficiency/accuracy of surgical automation versus manual component implantation in DA THA.

Methods

Retrospective review of 111 hips: 51 hips via automation and 60 hips via manual technique for DA THA.

Results

OR time averaged 8 min faster in the Automated group, compared to Manual group (p = 0.0009). Average femoral size was one size larger in the Automated group compared to Manual group (p = 0.007). No clinically significant differences were found between Manual and Automated groups for cup position or limb-length discrepancy. One calcar fracture occurred in the Automated group.

Conclusion

Surgical automation is efficient and accurate for DA THA.

Relationship between body mass index and the risk of periprosthetic joint infection after primary total hip arthroplasty and total knee arthroplasty

Background

Periprosthetic joint infection (PJI) is a disastrous complication after total hip arthroplasty (THA) and total knee arthroplasty (TKA). The relationship between body mass index (BMI) and the incidence of PJI remains controversial. To better understand the impact of increasing BMI on PJI, we conducted this study to investigate the dose-response relationship between BMI and the risk of PJI after primary THA or TKA.

Methods

A systematic search was conducted in PubMed, Embase, and Cochrane Library databases from inception to August 17, 2019. After study selection and data extraction, a dose-response meta-analysis was performed to investigate the relationship between BMI and PJI. Adjusted relative risks (RRs) with 95% confidence intervals (CIs) were pooled using fixed-effects or random-effects models.

Results

Eleven studies comprising 505,303 arthroplasties were included. The dose-response analysis showed a significant non-linear relationship between BMI and the risk of PJI (P_{non-linearity} <0.001). Patients following THA (RR, 1.489; 95% CI, 1.343–1.651; P<0.001) were more likely to suffer from PJI than patients following TKA. Furthermore, American Society of Anesthesiologists (ASA) score ≥3 (RR, 2.287; 95% CI, 1.650–3.170; P<0.001), lung disease (RR, 1.484; 95% CI, 1.208–1.823; P<0.001) and diabetes (RR, 1.695; 95% CI, 1.071–2.685; P=0.024) were identified as risk factors for PJI, but male (RR, 1.649; 95% CI, 0.987–2.755; P=0.056) and hypertension (RR, 0.980; 95% CI, 0.502–1.916; P=0.954) were not recognized as risk factors for PJI.

Conclusions

The J-shaped non-linear relationship demonstrated that increased BMI was associated with an increased risk for PJI after primary THA or TKA. Patients following THA were more likely to suffer from PJI than patients following TKA. Also, patients with ASA score ≥3, lung disease and diabetes have a higher risk of PJI. Gender and hypertension did not influence the incidence of PJI.

Timing of hip hemiarthroplasty and the influence on prosthetic joint infection

Introduction

Previous research suggested that patients have increased risk of infection with increased time from presentation with a femoral neck fracture to treatment with a hip hemiarthroplasty (HHA). The purpose of this study was to determine if rates of prosthetic joint infections within 3 months of surgery was affected by the time from patient presentation with a femoral neck fracture to the time of treatment with HHA.

Materials and methods

Acute hip fractures treated with HHA between 2005 and 2017 at three centres in Norway were enrolled in the study. Multi-trauma patients were excluded. Univariable analysis was performed to determine any significant effect of pre-operative waiting time on infection rate. Two pre-planned analyses dichotomizing pre-operative waiting time cut-offs were performed.

Results

There were 2300 patients with an average age of 82 (range, 48–100) years included of which 3.4% experienced a prosthetic joint infection within 3 months. The primary analysis found no significant difference in infection rate depending on time to surgery (OR = 1.06 (95% CI 0.94–1.20, p = 0.33)). The secondary analyses showed no significant differences in infection rates when comparing pre-operative waiting time of <24 hours vs ≥24 hours (OR = 0.92 (95% CI 0.58–1.46, p = 0.73)) and <48 hours vs ≥48 hours (OR = 1.39 (95% CI 0.81–2.38, p = 0.23)).

Conclusion

Based off of a large retrospective Norwegian database of hip fractures there did not appear to be a significant difference in infection rate based on pre-operative wait time to surgery.

Factores asociados a letalidad en pacientes con infección de herida quirúrgica. Estudio de casos y controles

Existe evidencia sobre los factores de riesgos asociados a la infección de la herida quirúrgica (IHQ), pero se desconocen estudios que hayan evaluado los factores asociados a la letalidad por la IHQ. Se propone un estudio para determinar los factores asociados a la letalidad en pacientes que desarrollaron una IHQ. Se realizó un estudio de casos y controles anidado a una cohorte de pacientes adultos diagnosticados con IHQ durante el periodo 2015 – 2016, en un hospital universitario de la región sur de Colombia. Los casos fueron pacientes con IHQ que presentaron letalidad dentro de los 30 días posteriores al inicio de la infección y los controles aquellos con IHQ que no fallecieron durante los 30 días. 150 pacientes cumplieron los criterios de selección. Los casos (fallecidos) correspondieron al 19,3%, quedando el grupo de los controles (vivos) con un 80,7%. Se encontró que controlando la edad y los días de hospitalización previos al procedimiento quirúrgico, la IHQ tipo órgano espacio es un factor asociado con letalidad en pacientes infectados (OR=2,5 IC95% 1,1 – 6,1). La letalidad en pacientes con IHQ fue elevada y representa un problema de salud pública por las consecuencias que ocasiona al paciente. 

The Effect of Negative Pressure Therapy on Closed Wound After the Orthopedic Surgery of Lower Limb: A Meta-Analysis

Background. Negative-pressure wound therapy is applied increasingly to manage closed wounds. However, no consensus has been reached with regard to surgical site infection and wound complication. Aim. To evaluate the effect of negative pressure therapy on closed wounds after orthopedic surgeries. Methods. PubMed, EMBASE, Cochrane Library, and MEDLINE databases were searched from 1966 to January 2019; the references in the identified studies were also searched. Results. Ten studies on arthroplasty and 3 studies on fractures were included. Significantly few infections appeared in the negative pressure group (odds ratio [OR] = 0.28, 95% confidence interval [CI] = 0.18-0.46, P < .001; I2 = 0%, P = .80). There was no significant difference for other complications (OR = 0.54, 95% CI = 0.21-1.39, P = .20; I2 = 81%, P < .001). Few patients needed reoperation in the negative pressure group (OR = 0.28, 95% CI = 0.14-0.53, P < .001; I2 = 0%, P = .82). Conclusion. Negative pressure therapy can decrease surgical site infection and reoperation of closed incisions.

Comparison of Functional Outcomes and Associated Complications in Patients Who Underwent Total Hip Arthroplasty for Femoral Neck Fracture in Relation to Their Underlying Medical Comorbidities

Purpose

In patients with independent mobility, full hip range of motion and sufficient muscle strength for daily life without cognitive impairment, treatment of a femoral neck fracture with total hip arthroplasty (THA) may be a better option compared to bipolar hip hemiarthroplasty. Here, functional outcomes and complications in patients who underwent THA for femoral neck fracture based on their comorbidity status were analyzed.

Materials and Methods

Between January 2013 and December 2018, 110 patients were treated with THA for femoral neck fractures at our institution. These patients were retrospectively analyzed for clinical outcomes at final follow-up (mean=24.4 months, range: 6-81 months) using the Harris hip score (HHS) and the presence or absence of two potential comorbidities: i) diabetes mellitus (DM; 35 with and 75 without) and ii) hypertension (HTN; 50 with and 60 without).

Results

The incidence of superficial infections at the surgical site in patients with DM was significantly higher compared with patients without DM (P=0.024). There were no significant differences in other potential complications based on DM status. HHS at final follow-up between patients with and without DM and with and without HTN were not significantly different (83.3 vs. 81.0, P=0.39 and 81.6 vs. 82.4, P=0.75, respectively).

Conclusion

Superficial infections occurred more frequently in patients with DM compared with patients without DM. DM and HTN status are not correlated with HHS.

Severe Obesity Increases Risk of Infection After Revision Total Hip Arthroplasty

BACKGROUND

The increasing prevalence of obesity has resulted in an increased number of revision total hip arthroplasties (rTHAs) performed in patients with a high body mass index (BMI). The aim of this study is to evaluate whether obesity negatively affects (1) complication rate, (2) reoperation and revision rate, and (3) patient-reported outcome in rTHA.

METHODS

In this registry-based study, we prospectively followed 444 rTHAs (cup: n = 265, stem: n = 57, both: n = 122) performed in a specialized high-volume orthopedic center between 2013 and 2015. The number of complications, and reoperation and revision surgery was registered until 5 years postoperatively. Oxford Hip Score (OHS) was evaluated preoperatively, and at 1 and 2 years postoperatively. Patients were categorized based on BMI to nonobese (<30 kg/m², n = 328), obese (30-35 kg/m², n = 82), and severe obese (≥35 kg/m², n = 34).

RESULTS

Severe obese patients, but not obese patients, had higher risks of complications and re-revision than nonobese patients. In particular, the risk of infection following rTHA was higher in severe obese patients (24%) compared to nonobese patients (3%; relative risk, 7.7). Severe obese patients had overall poorer OHS than nonobese patients, but improvement in OHS did not differ between severe obese and nonobese patients. No differences between obese and nonobese groups on OHS were observed.

CONCLUSION

In our study, severe obesity was associated with an increased risk of infection following rTHA. Patients with high BMI should be counseled appropriately before surgery.

Factors affecting the incidence of surgical site infection after geriatric hip fracture surgery: a retrospective multicenter study

Background

Geriatric hip fracture is a common type of osteoporotic fracture with high mortality and disability; surgical site infection (SSI) can be a devastating complication of this injury. By far, only a few studies identified easily remediable factors to reduce infection rates following hip fracture and less researches have focused on geriatric patients. The objective of this study was to identify potentially modifiable factors associated with SSI following geriatric hip fracture surgery.

Methods

This retrospective, multicenter study involves three level I hospitals. A total of 1240 patients (60 years or older) underwent hip surgery with complete data were recruited between January 2016 and June 2018. Demographics information, medications and additional comorbidities, operation-related variables, and laboratory indexes were extracted and analyzed. Receiver operating characteristic (ROC) analysis was performed to detect the optimum cut-off value for quantitative data. Univariate and multivariate logistic analysis model were performed respectively to identify the independent predictors.

Results

Ninety-four (7.58%) patients developed SSI in this study, and 76 (6.13%) had superficial infection, while 18 (1.45%) were diagnosed with deep infection. Results of univariate and multivariate analysis showed age > 79 years (OR, 2.60; p < 0.001), BMI > 26.6 kg/m² (OR, 2.97; p < 0.001), operating time > 107 min (OR, 2.18; p = 0.001), and ALB < 41.6 g/L (OR, 2.01; p = 0.005) were associated with an increased incidence of SSI; drainage use (OR, 0.57; p = 0.007) could reduce the incidence of wound infection for patients after geriatric hip fracture.

Conclusion

Accurate modifiable variables, operating time > 107 min, serum albumin < 41.6 g/L, BMI > 26.6 kg/m², and age > 79 years could be applied to distinguish geriatric patients with high-risk of postoperative surgical site infection.

Surgical approach does not affect deep infection rate after primary total hip arthroplasty

BACKGROUND

There is a concern for higher rates of wound complications and a potentially increased periprosthetic joint infection (PJI) risk after total hip arthroplasty (THA) with the direct anterior approach (DAA) compared to the posterolateral approach (PLA). Our purpose was to compare PJI risk after THA with the DAA or the PLA and to identify risk factors for PJI after primary THA.

METHODS

Clinical characteristics of patients treated in our institution with primary DAA or PLA THA between 1/2010 and 12/2015 were retrospectively reviewed. The respective deep PJI rates were calculated. A logistic regression model was constructed to determine a potential difference in the PJI risk between the 2 groups, and risk factors for hip PJI in all patients.

RESULTS

During the period studied, there were 1,182 DAA THAs and 18,853 PLA THAs. The PJI rate was 0.25% for the DAA group and 0.31% for the PLA group (p = 1.0). The DAA was not associated with a significantly increased risk for PJI compared to the PLA. Compared to younger patients, older patients had lower PJI risk; patient discharge to home was also associated with lower PJI risk compared to other discharge disposition; longer length of stay was associated with higher PJI risk compared to shorter length of stay.

CONCLUSION

The DAA is equally safe compared the PLA with respect to PJI risk. Younger age, discharge to facilities other than home and increased length of stay increase the risk for deep PJI after primary THA.

The Impact of Running, Monofilament Barbed Suture for Subcutaneous Tissue Closure on Infection Rates in Total Hip Arthroplasty: A Retrospective Cohort Analysis

BACKGROUND

Recently, running, monofilament barbed suture has become more popular as an efficient and economical alternative to traditional braided interrupted suture for wound closure following total joint arthroplasty. Its overall association with wound complications following surgery remains unknown at this time. Several studies have investigated its use in total knee arthroplasty (TKA), but there is limited literature surrounding use in total hip arthroplasty (THA). In this retrospective cohort study, our primary objective was to determine whether the use of monofilament barbed suture in THA was associated with reduced rates of postoperative infection when compared to traditional braided suture.

METHODS

Patients who underwent primary unilateral THA between November 2011 and December 2017 by a single senior surgeon with closure using either monofilament barbed suture (162 patients) or braided interrupted suture (429 patients) were retrospectively reviewed for postoperative wound complications during the first 90 days after surgery. Demographics, comorbidities, and perioperative data were also included to assess for risk factors for infection.

RESULTS

There was no difference between braided and barbed suture in overall rates of major complication, including periprosthetic joint infection (PJI) (0.47% vs 0.62%, P = .82) or revisions (1.86% vs 1.23%, P = .60). The overall rate of minor, superficial wound complications was also similar between both groups (6.1% vs 3.1%, P = .15). However, when superficial complications were categorized by type (dehiscence vs infection), the use of barbed suture was associated with a decreased rate of superficial wound infection (0% vs 5.4%, P = .003) and an increased rate of wound dehiscence (3.1% vs 0.7%, P = .04).

CONCLUSION

The use of monofilament barbed suture for superficial skin closure in THA leads to similar overall rates of both major and minor wound complications when compared to traditional interrupted braided suture. However, while barbed suture was associated with fewer superficial infections, there was an increased incidence of wound dehiscence. Overall, barbed suture demonstrated a cumulatively equivalent rate of superficial wound complications compared to braided suture. Based on this investigation, barbed suture appears safe to use in THA and may represent an efficient and effective alternative to braided suture for wound closure.

LEVEL OF EVIDENCE

Level IV; retrospective cohort study.

Predictors of Prolonged Length of Stay After Lumbar Interbody Fusion: A Multicenter Study

STUDY DESIGN

Retrospective analysis of a prospectively database.

OBJECTIVES

To identify factors associated with prolonged length of stay (LOS) in posterior /transforaminal lumbar interbody fusion (PLIF/TLIF).

METHODS

The subjects were patients who underwent PLIF/TLIF at 10 facilities from 2012 to 2014. A total of 1168 such patients with a mean age of 65.9 ± 12.5 years (range 18-87 years) were identified in the database. Operations were PLIF (n = 675), TLIF (n = 443), minimally invasive surgery (MIS)-PLIF (n = 22), and MIS-TLIF (n = 32). Age, gender, body mass index, ambulatory status, comorbidities, perioperative American Society of Anesthesiologists (ASA) grade, operative factors, and complications were examined. LOS was defined as the number of calendar days from the operation to hospital discharge. LOS was categorized as normal (<75th percentile) or prolonged (≥75th percentile).

RESULTS

The average LOS was 20.8 ± 9.8 days (range 7-77 days). There was a significant correlation between LOS and age (P < .05). Reoperation during hospitalization was performed in 20 cases for surgical site infection (n = 12), epidural hematoma (n = 5), and screw misplacement (n = 3). In multivariate analysis, prolonged LOS was associated with preoperative variables of age ≥70 years (odds ratio [OR] 1.87, 95% CI 1.38-2.54), and ASA class ≥III (OR 1.52, 95% CI 1.04-2.25); surgical variables of open procedures (OR 5.84, 95% CI 1.74-19.63), fused levels ≥3 (OR 5.17, 95% CI 3.17-8.43), operative time ≥300 minutes (OR 1.88, 95% CI 1.15-3.07), and estimated blood loss ≥500 mL (OR 1.71, 95% 1.07-2.75).

CONCLUSIONS

The factors identified in this study should help with obtaining informed consent, surgical planning and complication prevention to reduce health care costs associated with prolonged LOS.

DOES TOPICAL USE OF GENTAMICIN REDUCE THE INFECTION RATE IN PRIMARY TOTAL HIP ARTHROPLASTY?

OBJECTIVE

To determine whether the topical use of gentamicin reduces periprosthetic joint infection rates in primary total hip arthroplasty (THA).

METHODS

We retrospectively evaluated two cohorts of patients who underwent primary THA in a university hospital, with a minimum of 1-year postoperative follow-up and full clinical, laboratory, and radiological documentation. Patients who underwent operation in the first 59 months of the study period (263 hips) received only intravenous cefazolin as antibiotic prophylaxis (Cef group), and those who underwent operation in the following 43 months (170 hips) received intravenous cefazolin plus topical gentamicin directly applied on the wound as antibiotic prophylaxis (Cef + Gen group). For the diagnosis of periprosthetic joint infection, we used the criteria of the Centers for Disease Control and Prevention. Data were analyzed using the Fisher exact test, and p values of <0.05 were considered significant.

RESULTS

Thirteen hips (4.9%) in the Cef group and eight hips (4.7%) in the Cef + Gen group presented periprosthetic joint infection. Statistical analysis revealed no difference between the infection rates (p = 1.0).

CONCLUSION

Topical gentamicin as used in this study did not reduce periprosthetic joint infection rates in primary THA. Level of Evidence III, Retrospective comparative study.

Negative pressure wound therapy in total hip and knee arthroplasty: a meta-analysis

Aim: To assess the efficiency and safety of negative pressure wound therapy (NPWT) in the total hip and knee arthroplasty, we conducted a meta-analysis from randomized controlled trials. Methods: Potential academic articles were identified from the Cochrane Library, PubMed, Embase, Springer and ScienceDirect. Secondary sources were identified from the references of the included literature. RevMan 5.1 was used to analyze the pooled data. Results: Six randomized controlled trials met the inclusion criteria. Meta-analysis showed more superficial surgical site infection and blisters in patients with total knee arthroplasty. There were no significant differences between two groups in total infection and total complications. Conclusion: NPWT decreased the incidence of superficial surgical site infection. More blisters were noticed in patients with NPWT after total knee arthroplasty.

Outcomes of Superficial and Deep Irrigation and Debridement in Total Hip and Knee Arthroplasty

BACKGROUND

Following total knee arthroplasty and total hip arthroplasty, wound-related problems and deep periprosthetic joint infection may present in a similar fashion. Irrigation and debridement (I&D) has a great role in management of patients with early infection. The question that often arises is how to tell the difference between superficial and deep infection. This study evaluated the role and outcomes of both superficial and deep I&D in patients with wound-related issues and/or suspected periprosthetic joint infection.

METHODS

A retrospective study was conducted evaluating patients who underwent I&D within 28 days of total joint arthroplasty. A total of 176 cases with a minimum of 1-year follow-up were identified, and clinical records were reviewed in detail. Reoperations included superficial (fascia not opened) or deep (fascia opened) I&D. Failure was defined as the need for further surgical intervention within 1 year of initial I&D.

RESULTS

The overall success for superficial I&D was 84.28% vs 68.86% for deep I&D. The success of both deep and superficial I&D was higher if the I&D was performed closer to the index surgery. Superficial I&D in patients with a positive joint aspiration or evidence of intraoperative purulence or those in whom had no subcutaneous fluid had higher failure rates.

CONCLUSION

Superficial I&D is a viable option in patients with wound-related issues as long as joint aspiration is performed to rule out infection involving the prosthesis. If there are findings of no fluid or purulence, fascia may need to be opened and the deeper tissues explored.

Arthroplasty infection rates in fractured neck of femur: single vs dual antibiotic cement

INTRODUCTION

Mortality rates following hip arthroplasty range between 10% and 40% after 12 months. A higher rate is attributed to postoperative complications, of which surgical site infection is one of the most significant. In an effort to reduce surgical site infection following arthroplasty, antibiotics can be added to the cement used. The primary aim of this study was to determine whether dual antibiotic impregnated cement can reduce the rate of deep surgical site infection in patients following cemented arthroplasty for fractured neck of femur compared with single antibiotic impregnated cement. The secondary aim was to compare the rate of superficial surgical site infection in single compared with dual antibiotic cement.

MATERIALS AND METHODS

A total of 206 patients were included. Group 1 included 108 retrospective patients who underwent arthroplasty for neck of femur fracture over a 12-month period using single antibiotic impregnated cement. Group 2 included 98 prospective patients who underwent arthroplasty for neck of femur fracture over a 12-month period using dual antibiotic impregnated cement. The rates of deep and superficial surgical site infection were investigated.

RESULTS

Group 1 had a deep surgical site infection rate of 2.9% (n = 3), Group 2 had a deep surgical site infection rate of 0% (n = 0). Group 1 had a superficial surgical site infection rate of 3.7% (n = 4), Group 2 had a superficial surgical site infection rate of 5.1% (n = 5).

CONCLUSION

Dual antibiotic cement reduced the rate of deep surgical site infection compared with conventional single antibiotic cement in arthroplasty for fractured neck of femur. Only a marginal difference in superficial surgical site infection was observed.

Wound closure and follow-up after total knee arthroplasty - Do they affect the rate of antibiotic prescription?

BACKGROUND

This study aimed to evaluate risk factors for oral antibiotic prescription in the first six weeks after primary TKA, particularly whether the wound closure method (staples or sutures) and two-week follow-up clinician (surgeon or general practitioner (GP)) altered antibiotic use.

METHODS

Four thousand eight hundred forty-six TKAs from January 2013 to December 2016 at three tertiary hospitals in Auckland, New Zealand were analysed by manual review of patient electronic records and a national prescription database. Surgeon preference dictates the method of wound closure and whether wound review is followed up by the operating surgeon or by the patient's GP. Univariate and multivariate analysis was carried out to identify significant patient and surgical risk factors for oral antibiotic prescribing.

RESULTS

Oral antibiotics were prescribed in 24% of patients following primary TKA. Twenty-six percent of patients closed with staples were prescribed oral antibiotics versus 19% with sutures (adjusted OR = 1.4, p < 0.004). Excluding re-presentations and readmissions, GPs prescribed oral antibiotics in 22% of patients compared to seven percent of patients seen by surgeons (adjusted OR = 2.8, p < 0.001). Other risk factors for antibiotic prescription included increasing age, BMI and ASA score.

CONCLUSION

Oral antibiotic prescribing rates are higher if the wound was closed with staples and if a GP performed the two-week follow-up. Improved communication between surgeons and GPs are required to ensure adequate follow-up following TKA and appropriate oral antibiotic use.

Surface degradation-enabled osseointegrative, angiogenic and antiinfective properties of magnesium-modified acrylic bone cement

Objective

This work focuses on tackling the inadequate bone/implant interface strength of acrylic bone cements, which is a formidable problem diminishing their clinical performance, especially in percutaneous kyphoplasty surgery.

Methods

A new strategy of incorporating magnesium particles into clinically used poly(methylmethacrylate) (PMMA) bone cement to prepare a surface-degradable bone cement (SdBC) is proposed and validated both in vitro and in vivo.

Results

This surface degradation characteristic enables osseointegrative, angiogenic and antiinfective properties. SdBC showed fast surface degradation and formed porous surfaces as designed, while the desirable high compressive strengths (≥70 MPa) of the cement were preserved. Besides, the SdBC with proper Mg content promoted osteoblast adhesion, spreading, proliferation and endothelial cell angiogenesis capacity compared with PMMA. Also, SdBC demonstrated clear inhibitory effect on Staphylococcus aureus and Escherichia coli. In vivo evaluation on SdBC by the rat femur defect model showed that the bone/implant interface strength was significantly enhanced in SdBC (push-out force of 11.8 ± 1.5 N for SdBC vs 7.0 ± 2.3N for PMMA), suggesting significantly improved osseointegration and bone growth induced by the surface degradation of the cement. The injectability, setting times and compressive strengths of SdBC with proper content of Mg particles (2.8 wt% and 5.4 wt%) were comparable with those of the clinical acrylic bone cement, while the heat release during polymerization was reduced (maximum temperature 78 ± 1 °C for PMMA vs 73.3 ± 1.5 °C for SdBC).

Conclusions

This work validates a new concept of designing bioactive bone/implant interface in PMMA bone cement. And this surface-degradable bone cement possesses great potential for minimally invasive orthopaedic surgeries such as percutaneous kyphoplasty.

The translational potential of this article

This work reports PMMA/Mg surface-degradable acrylic bone cements that possess enhanced osseointegrative, angiogenic and antiinfective properties that are lacking in the clinically used acrylic bone cements. This new kind of bone cements could improve the treatment outcome of many orthopaedic surgeries such as percutaneous kyphoplasty and arthroplasty.

Iodine-supported titanium implants have good antimicrobial attachment effects

BACKGROUND

We have developed iodine-supported titanium implants, which were shown to have good anti-bacterial effects for Methicillin-sensitive Staphylococcus aureus (MSSA) in our past basic research. However, PJI can be caused by various bacteria including MRSA, Pseudomonas aeruginosa, MSSE, and fungus. The purpose of this study was to investigate whether these implants also have good antibacterial attachment effects for MRSA, P. aeruginosa, MSSE, and fungus.

METHODS

Ti-6Al-4V titanium plates were either left untreated (Ti), treated with oxide film on the Ti surface by anodization (Ti-O), or treated with an iodine coating on oxidation film (Ti-I). The antibacterial activity of the TiI was measured by experimental methods according to Japanese Industrial Standard (JIS) protocols. Implants in this study were exposed to MRSA (ATCC43300), P. aeruginosa (ATCC27853), MSSE (ATCC35984), and Candida Albicans (ATCC10231). Colonies were counted immediately after the bacteria attached to the metal surface and again after 24 h incubation. The difference in the number of bacteria on each metal plate was statistically investigated and an antibacterial activity value was calculated. An effective antibacterial active value of more than 2.0 was judged to be effective according to JIS protocol.

RESULTS

No countable viable bacteria were observed on the Ti-I surface. For all bacteria there was a significant difference in the mean number of viable bacteria between Ti-I and Ti or Ti-O. Antibacterial activity value in Ti-I and Ti-O was more than 5.9 and 3.6 respectively for MRSA, more than 2.8 and zero for P. aeruginosa, more than 4.3 and zero for MSSE, and more than 4.7 and zero for C. Albicans.

CONCLUSIONS

This study showed that iodine-supported titanium implants have good antimicrobial attachment effects for MRSA, P. aeruginosa, MSSE, and C. Albicans. Iodine-supported titanium implants could have great potential as innovative antibacterial implants that can prevent early onset periprosthetic joint infection.

An integrative care bundle to prevent surgical site infections among surgical hip patients: A retrospective cohort study

BACKGROUND

Surgical site infections (SSIs) following hip fracture surgeries have profound clinical and economic implications. The study aims to analyze the effect of an integrative SSI prevention care bundle on the SSI incidence among surgical hip patients. The study also aims to examine the association between SSI and mortality, readmission, duration of hospitalization, and hospital cost.

METHODS

A retrospective cohort study was carried out to assess the incidence of SSI in an acute hip unit in Singapore from January 2015 to September 2017. Patients who developed SSI fell into the exposure group, whereas patients without SSI fell into the nonexposure group. A comparison of the incidence of mortality, readmission, length of stay, and inpatient bill size was conducted between the 2 groups.

RESULTS

Among 758 hip surgeries performed during the study period, 14 (1.8%) SSIs were documented. Compared with patients with no SSI, patients with SSI were 4.27times more likely to be readmitted within 30days, had 2.47times longer length of stay, and 2.15times the inpatient bill size.

CONCLUSIONS

An integrative care bundle that capitalizes on the expertise of a multidisciplinary team has promoted shared responsibility and proven to be effective in preventing SSIs while contributing to better patient outcomes within the unit.

Using Patient-Reported Outcomes to Predict Revision Arthroplasty Following Femoral Neck Fracture: Enhancing the Value of Clinical Registries through Data Linkage

The aim of this study was to determine the association between patient-reported outcome measures (PROMs) six months following femoral neck fracture after a low fall and future arthroplasty, and the factors associated with this. Six-month post-fracture PROMs were collected from the Victorian Orthopaedic Trauma Outcomes Registry (VOTOR) for patients aged >55 years who were admitted for a femoral neck fracture after a low fall between March 2007 and June 2015. These cases were linked with those registered by Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) up to October 2016. Multivariable analysis was performed using a Cox proportional hazards model to determine factors associated with future arthroplasty, including six-month PROMs. Of the 7077 hip fracture patients registered by VOTOR during the study period, 2325 met the inclusion criteria. Internal fixation being used for the initial hip fracture surgery, being younger and having no pre-injury disability were all independently associated with future revision or conversion to arthroplasty. Out of all PROMs, reporting pain and discomfort six months post-fracture was associated with a 9.5-fold increase in the risk of future arthroplasty (95% CI: 3.81, 23.67). The value of clinical registries can be enhanced via data linkage, in this case by using PROMs to predict arthroplasty following femoral neck fracture.

Age alone is not a risk factor for periprosthetic joint infection

BACKGROUND

It is not known whether age alone or the increased comorbidities in older patients are responsible for the higher rate of periprosthetic joint infection (PJI) in older patients.

AIM

To test the hypothesis that age alone is not a risk factor for PJI after total joint arthroplasty.

METHODS

This retrospective study included the review of 23,966 patients undergoing primary total hip and knee arthroplasty between January 1^st, 2010 and December 31^st, 2016 at a single institution. Patients who developed PJI, as defined by International Consensus Meeting criteria, were identified. All enrolled patients were divided into three groups that included patients aged <65 years (N = 12,761), 65-74 years (N = 6850) and ≥75 years (N = 4355). Using multivariate analysis and propensity score matching analysis, the possible association between age and PJI was examined.

FINDINGS

The incidence of PJI in the entire cohort was 0.72% (171 out of 23,966). Multivariate analysis adjusting for all variables, except age, demonstrated that, compared to the patients aged <65 years, there was no statistically significant difference in the rate of PJI for patients aged 65-74 years (odds ratio: 0.89; 95% confidence interval: 0.55-1.42; P = 0.62) or for patients aged ≥75 years (0.69; 0.36-1.32; P = 0.26).

CONCLUSION

When adjusting for confounding variables, age alone is not a risk factor for PJI. Studies evaluating the influence of age on the incidence of PJI should take into account the other confounding variables that contribute to PJI.

The effectiveness of preoperative colon cleansing on post-operative surgical site infection after hip hemiarthroplasty

AIM

This study aimed to evaluate the effectiveness of prophylactic mechanical bowel preparation in elderly patients undergoing hip hemiarthroplasty in a single training institution over a period of 2 years.

PATIENTS AND METHODS

The study was conducted in a prospective-randomised manner. All patients, who underwent primary hip hemiarthroplasty for femoral neck fracture in our institution between 20 February 2015 and 29 December 2016, were included. B.T. Enema (sodium dihydrogen phosphate + disodium hydrogen phosphate) 135 ml (Yenisehir Laboratory, Ankara, Turkey) was used for colon cleansing.

RESULTS

Ninety-five patients were followed up for at least 1 year after surgery (16.3 ± 4.2 months). Of these, 46 were in the enema group and 49 were in the control group. Demographic and clinical characteristics of patients were similar in both groups (p > 0.05). Infection rates between the two groups were not significantly different (p > 0.05). In addition, ASA, age, sex, presence of diabetes mellitus, duration of surgery, time to surgery, ambulation status and blood count did not have a significant effect on surgical site infections (p > 0.05). However, all infections in the enema group were monobacterial and were successfully treated, whereas two of the four infections in the control group were polymicrobial and could not be successfully treated.

CONCLUSION

Although preoperative colon cleansing did not reduce the overall incidence of post-operative infections, our study suggested that it may reduce polymicrobial infections after hip hemiarthroplasty. Polymicrobial infections after hip hemiarthroplasty seem to have worse prognosis. Therefore, the effectiveness of preoperative colon cleansing in remediating such infections must be investigated in a larger number of patients.

Implementation of a multidisciplinary infections conference affects the treatment plan in prosthetic joint infections of the hip: a retrospective study

INTRODUCTION

Establishing a systematic multidisciplinary approach in the treatment of prosthetic joint infections (PJI) of the hip and analyzing its effect on clinical decision-making.

PATIENTS AND METHODS

Forty-six patients diagnosed with PJI of the hip were included in the retrospective study. The treatment plan was either established by a single-discipline approach (n = 20) or by a weekly multidisciplinary infections conference (n = 26) consisting of at least an orthopedic surgeon, microbiologist and pathologist. Recorded data included the length of hospital stay, number and type of surgeries, medical complications, recovered organisms as well as the number of applied antibiotics.

RESULTS

Patients discussed in the multidisciplinary infections conference showed a significantly shorter in-hospital stay (29 vs 62 days; p < 0.05), a significant reduction in surgeries (1.8 vs 5.1; p < 0.05) and a smaller number of antibiotics required (2.8 vs 4.2; p < 0.05). No significant difference could be found comparing inpatient complications between the two groups. Staphylococcus aureus and coagulase-negative staphylococci were the most frequently recovered organisms in both patient groups.

CONCLUSION

This study demonstrates the successful implementation of a weekly infections conference as an instrument to introduce a multidisciplinary approach to PJI of the hip. Implementation of these conferences significantly improves the treatment plan compared to a single-discipline approach, which we therefore highly recommend for other institutions. Multidiscipline may even affect clinical outcome which needs to be further investigated.

Four questions to identify patients with ASA III or higher

BACKGROUND

Increased age, obesity, and American Society of Anesthesiologists (ASA) Physical Status class III and IV have been reported as predictors for mortality and perioperative complications. High-volume institutions rely on central referral services as first contact point for patients. The current study reports on a simple four-step questionnaire to identify patients with ASA-physical status class III and IV to improve referral processes and optimize perioperative work ups.

MATERIALS AND METHODS

Seven hundred and seventy-five patients who called the physician referral service (PRS) at the author's institution and subsequently underwent surgery were enrolled in this study. The answers to the initial PRS questionnaire were analyzed. The study cohort consisted of 414 women (53.4%) and 361 men (46.6%) with an average age of 61.4 years (range 44-90 years) at the time of surgery.

RESULTS

Binary logistic regression revealed hypertension, diabetes mellitus (using medication), using blood thinner (other than Aspirin) and a number of 4-9 prescribed medication, respectively, as predictors for ASA III and IV. Receiver-operating characteristic (ROC) curve analysis identified a sensitivity of 82.4%, a specificity of 82.9%, and an accuracy of 82.8%, when two of these four questions are answered "yes". The area under the curve for this analysis was 0.876 [95% confidence interval (CI) 0.845-0.908]. Positive and negative likelihood ratios were 4.8 (95% CI 4.0-5.8) and 0.2 (95% CI 0.1-0.3), respectively.

CONCLUSIONS

This study revealed a simple four-step questionnaire to identify patients with ASA III or IV before a medical appointment. This helps to balance referrals between multiple providers in high-volume medical groups.

A Novel Risk Calculator Predicts 90-Day Readmission Following Total Joint Arthroplasty

BACKGROUND

A reliable prediction tool for 90-day adverse events not only would provide patients with valuable estimates of their individual risk perioperatively, but would also give health-care systems a method to enable them to anticipate and potentially mitigate postoperative complications. Predictive accuracy, however, has been challenging to achieve. We hypothesized that a broad range of patient and procedure characteristics could adequately predict 90-day readmission after total joint arthroplasty (TJA).

METHODS

The electronic medical records on 10,155 primary unilateral total hip (4,585, 45%) and knee (5,570, 55%) arthroplasties performed at a single institution from June 2013 to January 2018 were retrospectively reviewed. In addition to 90-day readmission status, >50 candidate predictor variables were extracted from these records with use of structured query language (SQL). These variables included a wide variety of preoperative demographic/social factors, intraoperative metrics, postoperative laboratory results, and the 30 standardized Elixhauser comorbidity variables. The patient cohort was randomly divided into derivation (80%) and validation (20%) cohorts, and backward stepwise elimination identified important factors for subsequent inclusion in a multivariable logistic regression model.

RESULTS

Overall, subsequent 90-day readmission was recorded for 503 cases (5.0%), and parameter selection identified 17 variables for inclusion in a multivariable logistic regression model on the basis of their predictive ability. These included 5 preoperative parameters (American Society of Anesthesiologists [ASA] score, age, operatively treated joint, insurance type, and smoking status), duration of surgery, 2 postoperative laboratory results (hemoglobin and blood-urea-nitrogen [BUN] level), and 9 Elixhauser comorbidities. The regression model demonstrated adequate predictive discrimination for 90-day readmission after TJA (area under the curve [AUC]: 0.7047) and was incorporated into static and dynamic nomograms for interactive visualization of patient risk in a clinical or administrative setting.

CONCLUSIONS

A novel risk calculator incorporating a broad range of patient factors adequately predicts the likelihood of 90-day readmission following TJA. Identifying at-risk patients will allow providers to anticipate adverse outcomes and modulate postoperative care accordingly prior to discharge.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Incidence and risk of surgical site infection after adult femoral neck fractures treated by surgery: A retrospective case-control study

Surgical site infections (SSI) are devastating complications after surgery for femoral neck fractures. There are a lot of literature have shown a strong association between diabetic patients and SSI. This study aimed to identify diabetes as an independent risk factor of SSI, focusing on femoral neck fractures, and to investigate the other potential risk factors for SSI.We retrospectively collected data from patients who underwent surgery for femoral neck fractures through the medical record management system at a single level 1 hospital between January 2015 and June 2016. Demographic and clinical patient factors and characteristics of SSI were recorded. The case group was defined as patients with SSI and the control group was defined as patients without SSI. Univariate and multivariate analyses were performed to determine the risk factors for SSI.Data were provided for 692 patients, among whom 26 had SSI, representing an incidence rate of 3.67%. In the SSI group, 24 (3.47%) patients had superficial infection and 2 (0.29%) had deep infection. On multivariate analysis, diabetes (P < .001) was determined an independent risk factor of SSI, so were surgery performed between May and September (P = .04), body mass index (P = .031), corticosteroid therapy (P = .003), anemia (P = .041), and low preoperative hemoglobin levels.Our results suggest that clinicians should recognize patients with these factors, particularly diabetes. And taking management optimally in the preoperative period will prevent the SSI after femoral neck fracture.