Risk Of Periprosthetic Joint Infection Research Articles

What's New in Musculoskeletal Infection.

What's New in Musculoskeletal Infection.

Symptomatic Benign Prostatic Hyperplasia: An Optimizable Risk Factor for Periprosthetic Joint Infection After Elective Primary Total Knee Arthroplasty

BackgroundWhether symptomatic benign prostatic hyperplasia (sBPH), which is common among middle-aged and older men, affects the risk of periprosthetic joint infection (PJI) remains controversial. The present study explored this question among men undergoing total knee arthroplasty and total hip arthroplasty (TKA and THA). MethodsWe retrospectively analyzed medical data from 948 men who underwent primary TKA or THA at our institution between 2010 and 2021. We compared the incidence of postoperative complications such as PJI, urinary tract infection (UTI), and postoperative urinary retention (POUR) between 316 patients (193 hips and 123 knees) who did and 632 patients who did not have sBPH; the 2 groups of patients were matched to each other in a 1:2 ratio based on numerous clinical demographic variables. In the subgroup analyses, we stratified sBPH patients according to whether they began anti-sBPH medical therapy prior to arthroplasty. ResultsPJI following primary TKA was significantly more common among sBPH patients than among patients who did not have sBPH (4.1 vs 0.4%; P = .029), as were UTI (P = .029), and POUR (P < .001). Patients who had sBPH also had an increased incidence of UTI (P = .006) and POUR (P < .001) following THA. Among sBPH patients, those who started anti-sBPH medical therapy before TKA suffered significantly lower incidence of PJI than those who did not. ConclusionSymptomatic benign prostatic hyperplasia is a risk factor for PJI after primary TKA among men, and starting appropriate medical therapy before surgery can reduce the risk of PJI following TKA and postoperative urinary complications following TKA and THA.

Does antibiotic bone cement reduce infection rates in primary total knee arthroplasty?

Infection after total knee arthroplasty (TKA) impacts the patient, surgeon, and healthcare system significantly. Surgeons routinely use antibiotic-loaded bone cement (ALBC) in attempts to mitigate infection; however, little evidence supports the efficacy of ALBC in reducing infection rates compared to non-antibiotic-loaded bone cement (non-ALBC) in primary TKA. Our study compares infection rates of patients undergoing TKA with ALBC to those with non-ALBC to assess its efficacy in primary TKA. A retrospective review of all primary, elective, cemented TKA patients over the age of 18 between 2011 and 2020 was conducted at an orthopedic specialty hospital. Patients were stratified into two cohorts based on cement type: ALBC (loaded with gentamicin or tobramycin) or non-ALBC. Baseline characteristics and infection rates determined by MSIS criteria were collected. Multilinear and multivariate logistic regressions were performed to limit significant differences in demographics. Independent samples t test and chi-squared test were used to compare means and proportions, respectively, between the two cohorts. In total, 9366 patients were included in this study, 7980 (85.2%) of whom received non-ALBC and 1386 (14.8%) of whom received ALBC. There were significant differences in five of the six demographic variables analyzed; patients with higher Body Mass Index (33.40 ± 6.27 vs. 32.09 ± 6.21; kg/m2) and Charlson Comorbidity Index values (4.51 ± 2.15 vs. 4.04 ± 1.92) were more likely to receive ALBC. The infection rate in the non-ALBC was 0.8% (63/7,980), while the rate in the ALBC was 0.5% (7/1,386). After adjusting for confounders, the difference in rates was not significant between the two groups (OR [95% CI]: 1.53 [0.69-3.38], p = 0.298). Furthermore, a sub-analysis comparing the infection rates within various demographic categories also showed no significant differences between the two groups. Compared to non-ALBC, the overall infection rate in primary TKA was slightly lower when using ALBC; however, the difference was not statistically significant. When stratifying by comorbidity, use of ALBC still showed no statistical significance in reducing the risk of periprosthetic joint infection. Therefore, the advantage of antibiotics in bone cement to prevent infection in primary TKA is not yet elucidated. Further prospective, multicenter studies regarding the clinical benefits of antibiotic use in bone cement for primary TKA are warranted.

Cemented versus Cementless Total Hip Arthroplasty for Femoral Head Osteonecrosis: A Study Based on National Claim Data in South Korea.

The purpose of this study was to compare the rates of revision, periprosthetic joint infection (PJI), and periprosthetic fracture (PPF) between patients with osteonecrosis of the femoral head (ONFH) undergoing noncemented total hip arthroplasty (THA) and cemented THA using a national claim data in South Korea. We identified patients who received THA for ONFH from January 2007 to December 2018 using ICD diagnosis codes and procedural codes. Patients were categorized into two groups according to the fixation method: with or without cement. The survivorship of THA was calculated using the following end points: revision of both the cup and stem, revision of the single component, any type of revision, PJI, and PPF. A total of 40,606 patients: 3,738 patients (9.2%) with cement and 36,868 patients (90.7%) without cement, received THA for ONFH. The mean age of the noncemented fixation group (56.2 ± 13.2 years) was significantly lower than that of the cemented fixation group (57.0 ± 15.7 years, P = 0.003). The risk of revision and PJI was notably higher in cemented THA (hazard ratio: 1.44 [1.21 to 1.72] and 1.66 [1.36 to 2.04], respectively). Noncemented THA had a higher 12-year survivorship compared with cemented THA with any revision and PJI as the end point. Noncemented fixation had better survivorship than cemented fixation in patients with ONFH.

Effect of non-cephalosporin antibiotic prophylaxis on the risk of periprosthetic joint infection after total joint replacement surgery: a retrospective study with a 1-year follow-up

Cephalosporins are recommended as first-line antibiotic prophylaxis in total joint replacement surgery. Studies have shown an increased risk for periprosthetic joint infection (PJI) when non-cephalosporin antibiotics have been used. This study examines the effect of non-cephalosporin antibiotic prophylaxis on the risk for PJI. Patients with a primary hip or knee replacement performed from 2012 to 2020 were identified (27 220 joint replacements). The primary outcome was the occurrence of a PJI in a one-year follow-up. The association between perioperative antibiotic prophylaxis and the outcome was examined using logistic regression analysis. Cefuroxime was used as prophylaxis in 26,467 operations (97.2%), clindamycin in 654 (2.4%) and vancomycin in 72 (0.3%). The incidence of PJI was 0.86% (228/26,467) with cefuroxime and 0.80% (6/753) with other prophylactic antibiotics. There was no difference in the risk for PJI with different prophylactic antibiotics in the univariate (OR 1.06, 95% CI 0.47-2.39) or multivariable analysis (OR 1.02, 95% CI 0.45-2.30). Non-cephalosporin antibiotic prophylaxis in primary total joint replacement surgery was not associated with an increased risk for PJI.

Invasive Gastrointestinal Endoscopy Following Total Joint Arthroplasty Increases the Risk for Periprosthetic Joint Infection

BackgroundThe safety of postoperative colonoscopy and endoscopy following total joint arthroplasty (TJA) remains largely unknown. The objective of this study was to characterize the effect of gastrointestinal endoscopic procedures after TJA on the risk of postoperative periprosthetic joint infection (PJI). MethodsUsing a large national database, patients who underwent an endoscopic procedure (colonoscopy or esophagogastroduodenoscopy (EGD)) within 12 months after primary TJA were identified and matched in a 1:1 fashion based on procedure (primary total knee arthroplasty (TKA) versus total hip arthroplasty (THA)), age, sex, Charlson Comorbidity Index (CCI), and smoking status with patients who did not undergo endoscopy. A total of 142,055 patients who underwent endoscopy within 12 months following TJA (96,804 TKAs and 45,251 THAs) were identified and matched. The impact of timing of endoscopy relative to TJA on postoperative outcomes was assessed. Preoperative comorbidity profiles and 1-year complications were compared. Statistical analyses included Chi-squared tests and multivariate logistic regressions with outcomes considered significant at P < .05. ResultsMultivariate analyses revealed that endoscopy within 2 months following TKA and 1 month of THA was associated with a significantly increased odds of periprosthetic joint infection (odds ratio (OR): 1.29 [1.08-1.53]; P = .004; OR: 1.41 [1.01-1.90]; P = .033, respectively). Patients who underwent endoscopy greater than 2 months from the timing of their TKA and 1 month from THA were not at significantly greater risk of developing PJI. ConclusionThese data suggest that invasive endoscopic procedures should be delayed if possible by at least 2 months following TKA and 1 month following THA to minimize the risk of PJI.

Pre-operative corticosteroid injection within 1 month of total shoulder arthroplasty is associated with increased risk of periprosthetic joint infection.

Corticosteroid injections (CSI) may increase the risk of peri-prosthetic infections (PJI) following total shoulder arthroplasty (TSA). Our study specifically assessed the risk of PJI in patients who received CSI: (1) less than 4 weeks prior to TSA; (2) 4-8 weeks prior to TSA; and (3) 8-12 weeks prior to TSA. A national all-payer database was queried to identify patients who underwent TSA with a shoulder osteoarthritis diagnosis from October 1, 2015 to October 31, 2020 (n = 25,422). There were four cohorts: CSI within 4 weeks of TSA (n = 214), CSI 4-8 weeks prior to TSA (n = 473), CSI 8-12weeks prior to TSA (n = 604), and a control cohort that did not receive CSI (n = 15,486). Bivariate chi-square analyses of outcomes were performed in addition to multivariate regression. A significant increase in PJI risk at 1 year (Odds Ratio [OR] = 2.29, 95% Confidence Interval [CI] = 1.19-3.99, p = 0.007) and 2 years (OR = 2.03, CI = 1.09-3.46, p = 0.016) in patients who received CSI within 1 month of TSA was noted. PJI risk was not significantly increased at any time point for patients who received a CSI greater than 4 weeks prior to TSA (all p ≥ 0.396). PJI risk is increased at both 1 and 2 years post-operatively in patients who received a CSI within 4 weeks of TSA. Therefore, TSA should be deferred at least 4 weeks after a patient receives a CSI to mitigate PJI risk. Level III.

THE LIFETIME REVISION RISK OF UNICOMPARTMENTAL KNEE ARTHROPLASTY

Unicompartmental knee arthroplasty (UKA) is associated with a higher risk of revision compared with total knee arthroplasty (TKA). The outcomes of knee arthroplasty are typically presented as implant survival or incidence of revision after a set number of years, which can be difficult for patients and clinicians to conceptualise. We aimed to calculate the ‘lifetime risk’ of revision for UKA as a more relatable estimate of risk projection over a patient's remaining lifetime, and make comparisons to TKA. All primary UKAS performed from 1999 to 2019 (n=13,481) captured by the New Zealand Joint Registry (NZJR) were included. The lifetime risk of revision was calculated and stratified by age, gender and American Society of Anesthesiologists (ASA) status. The lifetime risk of revision for UKA was highest in the youngest patients (46-50 years; 40.4%) and lowest in the oldest patients (86-90 years; 3.7%). Lifetime risk of revision was higher for females (range 4.3%-43.4% cf. males 2.9%-37.4%) and patients with higher ASA status (ASA 3-4 range 8.8%-41.2% cf. ASA 1 1.8%-29.8%), regardless of age. The lifetime risk of UKA was two-fold higher than TKA (ranging from 3.7%-40.4% UKA, 1.6%-22.4% TKA) across all age groups. Increased risk of revision in the younger patients was associated with aseptic loosening in both males and females, and pain in females. Periprosthetic joint infections (PJI) accounted for 4% of all UKA revisions, in contrast to 27% for TKA; risk of PJI was higher for males than females for both procedures. The lifetime risk of revision is a more meaningful measure of arthroplasty outcomes and can aid with patient counselling prior to UKA. Findings from this study show the increased lifetime risk of UKA revision for younger patients, females and those with higher ASA status.

ERYTHROMYCIN-DOPED NANOFIBRE COATING ENHANCES OSSEOINTEGRATION AND INHIBITS STAPHYLOCOCCUS AUREUS-INDUCED OSTEOLYSIS

Failure of osseointegration and periprosthetic joint infection (PJI) are the two main reasons of implant failure after total joint replacement (TJR). Nanofiber (NF) implant surface coating represents an alternative local drug eluting device that improves osseointegration and decreases the risk of PJI. The purpose of this study was to investigate the therapeutic efficacies of erythromycin (EM)-loaded coaxial PLGA/PCL-PVA NF coating in a rat S. aureus-infected tibia model.NF coatings with 100mg and 1000mg EM were prepared. NF without EM was included as positive control. 56 Sprague Dawley rats were divided into 4 groups. A titanium pin (1.0-mm x 8 mm) was placed into the tibia through the intercondylar notch. S. aureus (SA) was introduced by both direct injection of 10 μl broth (1 × 104 CFU) into the medullary cavity and single dip of Ti pins into a similar solution prior to insertion. Rats were sacrificed at 8 and 16 weeks after surgery. The outcome measurements include μCT based quantitative osteolysis evaluation and hard tissue histology.Results: EM-NF coating (EM100 and EM1000) reduced osteolysis at 8 and 16 weeks, compared to EM0 and negative control. The effective infection control by EM-NFs was further confirmed by hard tissue section analysis. The Bone implant contact (BIC) and bone area fraction Occupancy (BAFO) within 200 µm of the surface of the pins were used to evaluate the osseointegration and new bone formation around the implants. At 16 weeks, the bone implant contact (BIC) of EM 100 (35.08%) was higher than that of negative control (3.43%) and EM0 (0%). The bone area fraction occupancy within 200 µm (BAFO) of EM100 (0.63 mm2) was higher than that of negative control (0.390 mm2) and EM0 (0.0 mm2). The BAFO of EM100 was also higher than that of EM1000 (0.3mm2).There was much less osteolysis observed with EM100 and EM1000 NF coatings at 16 weeks, as compared to EM0 positive control, p=0.08 and p=0.1, respectively. Osseointegration and periprosthetic bone formation was enhanced by EM-NFs, especially EM100. Data from this pilot study is promising for improving implant surface fabrication strategies.

The effect of autoimmune skin disorders on post-operative outcomes following arthroplasty

IntroductionThe impact of autoimmune skin disorders on post-operative outcomes after TJA is conflicting and studies are limited by small sample sizes. The purpose of this study is to analyze a range of common autoimmune skin disorders and identify whether an increased risk of post-operative complication exists after total joint arthroplasty. MethodsData was collected from NIS database for patients diagnosed with autoimmune skin disorder (psoriasis, lupus, scleroderma, atopic dermatitis) and who underwent total hip arthroplasty (THA), total knee arthroplasty (TKA), or other TJA (shoulder elbow, wrist, ankle) between 2016 and 2019. Demographic, social, and comorbidity data was collected. Multivariate regression analyses were performed to assess the independent influence of autoimmune skin disorder on each post-operative outcome including implant infection, transfusion, revision, length of stay, cost, and mortality. ResultsAmong 55,755 patients with autoimmune skin disease who underwent TJA, psoriasis was associated with increased risk of periprosthetic joint infection following THA (odds ratio 2.44 [1.89–3.15]) and increased risk of transfusion following TKA (odds ratio 1.33 [1.076–1.64]). Similar analyses were performed for systemic lupus erythematosus, atopic dermatitis, and scleroderma, however no statistically significant associations were observed in any of the six collected post-operative outcomes. ConclusionThis study suggests psoriasis is an independent risk factor for poorer post-operative outcomes following total joint arthroplasty, however similar risk was not observed for other autoimmune skin disorders such as lupus, atopic dermatitis, or scleroderma.

INFLUENCE OF ANTIBACTERIAL IMPLANT COATINGS ON THE VIABILITY OF GRAM-POSITIVE AND GRAM-NEGATIVE BACTERIA AND THE IN VITRO MINERALIZATION

The implantation of endoprosthesis is a routine procedure in orthopaedics. Endoprosthesis are mainly manufactured from ceramics, polymers, metals or metal alloys. To ensure longevity of the implants they should be as biocompatible as possible and ideally have antibacterial properties, to avoid periprosthetic joint infections (PJI). Various antibacterial implant materials have been proposed, but have so far only been used sporadically in patients. PJI is one of the main risk factors for revision surgeries. The aim of the study was to identify novel implant coatings that both exhibit antibacterial properties whilst having optimal biocompatibility.Six different novel implant coatings and surface modifications (EBM TiAl6V4, strontium, TiCuN, TiNbN, gentamicin phosphate (GP), gentamicin phosphate+cationic polymer (GP+CP)) were compared to standard CoCrMo-alloy. The coatings were further characterized with regard to the surface roughness. E. coli and S. capitis were cultured on the modified surfaces to investigate the antibacterial properties. To quantify bacterial proliferation the optical density (OD) was measured and viability was determined using colony forming units (CFU). Murine bone marrow derived macrophages (BMMs) were cultured on the surfaces and differentiated into osteoblasts to quantify the mineralisation using the alizarin red assay.All novel coatings showed reduced bacterial proliferation and viability compared to standard CoCrMo-alloy. A significant reduction was observed for GP and GP+CP coated samples compared to CoCrMo (ODGP,E.coli = 0.18±0.4; ODGP+CP,E.coli = 0.13±0.3; p≤0.0002; N≥7-8). An increase in osteoblast-mediated mineralisation was observed on all surfaces tested compared to CoCrMo. Furthermore, GP and GP+CP coated samples showed a statistically significant increase (MGP = 0.21±0.1; MGP+CP = 0.25±0.2; p&lt;0.0001; N≥3-6).The preliminary data indicates that the gentamicin containing surfaces have the most effective antibacterial property and the highest osseointegrative capacity. The use of antibiotic coatings on prostheses could reduce the risk of PJI while being applied on osseointegrative implant surfaces.

Peripheral Nerve Block Utilization is Associated With Decreased Postoperative Opioid Consumption and Shorter Length of Stay Following Total Knee Arthroplasty.

This study aims to examine differences in postoperative complications and opioid consumption associated with perioperative peripheral nerve block (PNB) utilization during primary total knee arthroplasty (TKA). The Premier Healthcare Database was queried for adult patients who underwent primary, elective TKA from 2015 to 2020. Patients who received a femoral or adductor canal PNB were compared to patients who did not. PNB utilization was trended from 2015 to 2020. Univariate and multivariate regression analyses were performed to assess differences in the 90-day risk of postoperative complications between groups. The average inpatient opioid consumption in morphine milligram equivalents was assessed as a function of length of stay. Overall, 609,991 patients were included. PNB utilization increased from 9.29% in 2015 to 30.3% in 2020. After controlling for confounders, the PNB cohort was more likely to have same-day discharge (adjusted odds ratio [aOR] 1.88) and had a decreased risk of periprosthetic joint infection (aOR 0.87), pulmonary embolism (aOR 0.81), and respiratory failure (aOR 0.78). However, there was an increased risk of seroma (aOR 1.75) and hematoma (aOR 1.22) associated with PNB utilization. Lower average overall opioid exposure was seen in the PNB cohort vs no-PNB cohort (82.1 ± 194.7 vs 89.4 ± 214.1 morphine milligram equivalents, P < .001). PNB utilization during primary TKA is associated with a shorter length of stay and decreased risk of multiple postoperative complications, as well as reduced postoperative opioid consumption. These data provide evidence in support of the safety and efficacy of this emerging practice. However, the clinical relevance of an increased risk of seroma and hematoma formation may warrant further investigation.

Application of the Mayo Periprosthetic Joint Infection Risk Score for Total Ankle Arthroplasty.

Assessing patient's risk of infection is fundamental for prevention of periprosthetic joint infection (PJI) after total ankle arthroplasty (TAA). The Mayo Prosthetic Joint Infection Risk Score (Mayo Score) is based on data from total hip and knee arthroplasty and has not been validated for application for TAA. A total of 405 consecutive TAA cases were followed for 6 months for PJI. Individual patients' Mayo Scores were calculated and analyzed with logistic regression and receiver operating characteristic (ROC) for predictability for PJI. A critical cut-off Mayo Score for patients at high risk of PJI was determined by best Youden index. Among the Mayo Score-defined high-risk patients, the contribution of different risk factors were compared between the PJI and non-PJI patients. There were 10 cases of PJI (2.5%) among the 405 cases within 6 months after TAA. Of the 405 patients, the Mayo Scores ranged between -4 and 13 (median 2; interquartile range 0-5). The average Mayo Score was 2.5 ± 3.4 in the non-PJI patients and 7.7 ± 3.1 in the PJI patients (P < .001). Logistic regression showed that the probability of PJI increased with higher Mayo Scores (odds ratio 1.48, 95% CI 1.23-1.78). All but 1 PJI patients had a Mayo Score >5. The sensitivity and specificity were 90.0% and 84.3%, respectively, when a Mayo Score >5 was used as a criterion for high risk of PJI. This study demonstrated that the Mayo Score could similarly predict PJI risk after TAA as in total hip and knee arthroplasty. Data analysis suggests that a Mayo Score >5 could be a criterion for identifying high-risk patients for PJI, although further validation with a large number of PJI cases is necessary. Level II, developing diagnositic criteria with consecutive cases.

What is the Safe Distance Between Hip and Knee Implants to Reduce the Risk of Ipsilateral Metachronous Periprosthetic Joint Infection?

Periprosthetic joint infection (PJI), the most common cause of revision after TKA and THA, is a devastating complication for patients that is difficult to diagnose and treat. An increase in the number of patients with multiple joint arthroplasties in the same extremity will result in an increased risk of ipsilateral PJI. However, there is no definition of risk factors, micro-organism patterns, and safe distance between knee and hip implants for this patient group. (1) In patients with hip and knee arthroplasties on the same side who experience a PJI of one implant, are there factors associated with the development of subsequent PJI of the other implant? (2) In this patient group, how often is the same organism responsible for both PJIs? (3) Is a shorter distance from an infected prosthetic joint to an ipsilateral prosthetic joint associated with greater odds of subsequent infection of the second joint? We designed a retrospective study of a longitudinally maintained institutional database that identified all one-stage and two-stage procedures performed for chronic PJI of the hip and knee at our tertiary referral arthroplasty center between January 2010 and December 2018 (n = 2352). Of these patients, 6.8% (161 of 2352) had an ipsilateral hip or knee implant in situ at the time of receiving surgical treatment for a PJI of the hip or knee. The following criteria led to the exclusion of 39% (63 of 161) of these patients: 4.3% (seven of 161) for incomplete documentation, 30% (48 of 161) for unavailability of full-leg radiographs, and 5% (eight of 161) for synchronous infection. With regard to the latter, per internal protocol, all artificial joints were aspirated before septic surgery, allowing us to differentiate between synchronous and metachronous infection. The remaining 98 patients were included in the final analysis. Twenty patients experienced ipsilateral metachronous PJI during the study period (Group 1) and 78 patients did not experience a same-side PJI (Group 2). We analyzed the microbiological characteristics of bacteria during the first PJI and ipsilateral metachronous PJI. Calibrated, full-length plain radiographs were evaluated. Receiver operating characteristic curves were analyzed to determine the optimal cutoff for the stem-to-stem and empty native bone distance. The mean time between the initial PJI and ipsilateral metachronous PJI was 8 ± 14 months. Patients were followed for a minimum of 24 months for any complications. The risk of ipsilateral metachronous PJI in the other joint secondary to a joint implant in which PJI develops can increase up to 20% in the first 2 years after the procedure. There was no difference between the two groups in age, sex, initial joint replacement (knee or hip), and BMI. However, patients in the ipsilateral metachronous PJI group were shorter and had a lower weight (1.6 ± 0.1 m and 76 ± 16 kg). An analysis of the microbiological characteristics of bacteria at the time of the initial PJI showed no differences in the proportions of difficult-to-treat, high virulence, and polymicrobial infections between the two groups (20% [20 of 98] versus 80% [78 of 98]). Our findings showed that the ipsilateral metachronous PJI group had a shorter stem-to-stem distance, shorter empty native bone distance, and a higher risk of cement restrictor failure (p < 0.01) than the 78 patients who did not experience ipsilateral metachronous PJI during the study period. An analysis of the receiver operating characteristic curve showed a cutoff of 7 cm for the empty native bone distance (p < 0.01), with a sensitivity of 72% and a specificity of 75%. The risk of ipsilateral metachronous PJI in patients with multiple joint arthroplasties is associated with shorter stature and stem-to-stem distance. Appropriate position of the cement restrictor and native bone distance are important in reducing the risk of ipsilateral metachronous PJI in these patients. Future studies might evaluate the risk of ipsilateral metachronous PJI owing to bone adjacency. Level III, therapeutic study.

Visceral Fat as a Risk Factor for Periprosthetic Joint Infection After Total Hip and Knee Arthroplasty

BackgroundVisceral obesity, a strong indicator of chronic inflammation and impaired metabolic health, has been shown to be associated with poor postoperative outcomes and complications. This study aimed to evaluate the relationship between visceral fat area (VFA) and periprosthetic joint infection (PJI) in total joint arthroplasty (TJA) patients. MethodsA retrospective study of 484 patients who had undergone a total hip or knee arthroplasty was performed. All patients had a computed tomography scan of the abdomen/pelvis within two years of their TJA. Body composition data (ie, VFA, subcutaneous fat area, and skeletal muscle area) were calculated at the Lumbar-3 vertebral level via two fully automated and externally validated machine learning algorithms. A multivariable logistic model was created to determine the relationship between VFA and PJI, while accounting for other PJI risk factors. Of the 484 patients, 31 (6.4%) had a PJI complication. ResultsThe rate of PJI among patients with VFA in the top quartile (> 264.1 cm2) versus bottom quartile (< 82.6 cm2) was 5.6% versus 10.6% and 18.8% versus 2.7% in the total hip arthroplasty and total knee arthroplasty cohorts, respectively. In the multivariate model, total knee arthroplasty patients with a VFA in the top quartile had a 30.5 times greater risk of PJI than those in the bottom quartile of VFA (P = .0154). ConclusionVFA may have a strong association with PJI in TJA patients. Using a standardized imaging modality like computed tomography scans to calculate VFA can be a valuable tool for surgeons when assessing risk of PJI.

More complications and higher transfusion rate in patients with rheumatoid arthritis than osteoarthritis undergoing total hip arthroplasty.

Total hip arthroplasty (THA) in patients with rheumatoid arthritis (RA) has been associated with an increased risk of periprosthetic joint infection, periprosthetic fractures, dislocations, and post-operative blood transfusion. However, higher post-operative blood transfusion is unclear whether it reflects peri-operative blood loss or is characteristic of RA. This study aimed to compare the complications, allogenic blood transfusion, albumin use, and peri-operative blood loss between patients who underwent THA because of RA or osteoarthritis (OA). Patients undergoing cementless THA for hip RA (n = 220) or hip OA (n = 261) at our hospital between 2011 and 2021 were retrospectively enrolled. Deep vein thrombosis, pulmonary embolism, myocardial infarction, calf muscular venous thrombosis, wound complications, deep prosthetic infection, hip prosthesis dislocation, periprosthetic fractures, 30-day mortality, 90-day readmission, allogeneic blood transfusion, and albumin infusions were considered as primary outcomes, while secondary outcomes included the number of perioperative anaemia patients as well as total, intra-operative, and hidden blood loss. Compared to the OA group, patients with hip RA showed significantly higher rates of wound aseptic complications, hip prosthesis dislocation, homologous transfusion, and albumin use. RA patients also showed a significantly higher prevalence of pre-operative anemia. However, no significant differences were observed between the two groups in total, intra-operative, or hidden blood loss. Our study suggests that RA patients undergoing THA are at a higher risk of wound aseptic complications and hip prosthesis dislocation than patients with hip OA. Pre-operative anaemia and hypoalbuminaemia in patients with hip RA place them at a significantly higher risk of post-operative blood transfusion and use of albumin.

Clinical Outcomes and Complication Rate after Single-Stage Hardware Removal and Total Hip Arthroplasty: A Matched-Pair Controlled Study

Single-stage hardware removal and total hip arthroplasty is a complex surgical procedure, comparable to revision surgery. The purpose of the current study is to evaluate single-stage hardware removal and THA outcomes, compare this technique with a matched control group that has undergone primary THA and assess the risk of periprosthetic joint infection with a 24-month minimum follow-up. This study included all those cases treated with THA and concomitant hardware removal from 2008 to 2018. The control group was selected on a 1:1 ratio among patients who underwent THA for primary OA. The Harris Hip (HHS) and University of California at Los Angeles Activity (UCLA) scores, infection rate and early and delayed surgical complications were recorded. One hundred and twenty-three consecutive patients (127 hips) were included, and the same number of patients was assigned to the control group. The final functional scores were comparable between the two groups; a longer operative time and transfusion rate were recorded in the study group. Finally, an increased incidence of overall complications was reported (13.8% versus 2.4%), but no cases of early or delayed infection were found. Single-stage hardware removal and THA is a safe and effective but technically demanding technique, with a higher incidence of overall complications, making it more similar to revision THA than to primary THA.

Safety of total elbow arthroplasty in patients with rheumatoid arthritis and prior hip or knee periprosthetic joint infection

BackgroundThe volumes of upper and lower extremity arthroplasty are increasing. Periprosthetic joint infection (PJI) after TEA remains a substantial cause of morbidity, with certain studies reporting primary total elbow arthroplasties (TEA) PJI rates over 10%. The odds ratio for hip and knee PJI after previous hip or knee PJI is 3 times, and it rises to 15 times for patients on chronic suppressive antibiotics. The risk of PJI for primary TEA in patients with a history of lower extremity PJI is unknown. The purpose of this study, therefore, was to compare the incidence of PJI after primary TEA in patients with a history of lower extremity PJI in a case-control study. MethodsOur institutional joint registry database was queried to identify all patients who underwent primary TEA and had previously undergone treatment for lower extremity PJI between 1974 and 2021. Twelve elbows (10 patients) with a mean follow-up of 8.2 years were identified. There were 9 female elbows (75%) and 3 male elbows (25%) with a mean age of 63 years (range,44-78 years), and all patients had a diagnosis of rheumatoid arthritis. This cohort was 1:7 matched (age, sex, side, indication, and surgical year) to 84 elbows (83 patients) with no history of lower extremity PJI. There were no statistically significant differences between the cohorts with regard to body mass index or operative time. Survivorship analysis free of TEA PJI with death as a competing risk was calculated. ResultsNone of the 12 TEA included in the study group developed PJI. The cumulative incidence of PJI in the matched cohort at 10 years was 6.4% (5 elbows). There was 1 superficial infection in the study group (9.1%) and 5 (5.8%) in the matched cohort. In the study group, 2 elbows underwent revision and 4 underwent reoperation. Eight elbows in the matched cohort underwent revision and 23 underwent reoperation. The study cohort was associated with higher risk of revision and reoperation for any cause, but these differences did not reach statistical significance. ConclusionIn this relatively small case control study, there was no incidence of PJI in patients who underwent primary TEA for rheumatoid arthritis and had previously undergone treatment for lower extremity PJI. The cumulative incidence of PJI in the matched cohort at 10 years was 6.4%. Although underpowered to make firm conclusions, it does draw from a very large population of patients and did not reveal an association between infection after TEA and a prior history of lower extremity PJI.

Mapping bacterial biofilm on explanted orthopedic hardware: An analysis of 14 consecutive cases.

Hardware implanted during primary total joint arthroplasty carries a serious risk for periprosthetic joint infection (PJI). The formation of bacterial biofilms, which are highly tolerant of antibiotics and host immunity, is recognized as being a major barrier to treatment. It is not known whether some components and their surface features are more prone to biofilm than others. This study attempted to map biofilm on different components and features of orthopedic hardware recovered during revision. Implant surface culture (ISC) was used on 53 components from 14 hip and knee revisions. ISC achieves a thin agar coating over components, followed by incubation and observation for colony outgrowth over 9 days. Recovered organisms were identified by selective culture and 16s rRNA sequencing. Outcomes were compared with clinical culturing and PJI diagnosis based on 2013 Musculoskeletal Infection Society criteria. ISC paralleled clinical culturing with a sensitivity of 100% and a specificity of 57.1%. When compared to Musculoskeletal Infection Society criteria, sensitivity remained at 100% while specificity was 80%. Biofilm accumulation was patchy and heterogeneous throughout different prostheses, though notably the non-articulating surfaces between the tibial tray and polyethylene insert showed consistent growth. On individual components, ridges and edges consistently harbored biofilm, while growth elsewhere was case dependent. ISC successfully identified microbial growth with high sensitivity while also revealing that biofilm growth was commonly localized to particular locations. Understanding where biofilm formation occurs most often on implanted hardware will help guide debridement, retention choices, and implant design.

The Cost-Effectiveness of Wound Dressings for Infection Prophylaxis in Total Joint Arthroplasty: An Economic Evaluation

Background Periprosthetic joint infection (PJI) is a medical and economical challenge. Specific post-operative wound dressings have been developed to mitigate risk of PJI following total hip arthroplasty (THA) and total knee arthroplasty (TKA), but these come with added cost and unknown benefit. The purpose of this study was to determine which dressings may be economically justifiable. Methods The average added cost of Xeroform with gauze (Xeroform+gauze), Mepilex Border, Aquacel Ag, and Dermabond Prineo dressings compared to standard dressing (Xeroform+gauze) only were obtained from institutional records and contemporary literature. Baseline infection rates following THA and TKA and average costs of PJI treatment were obtained from the literature. A break-even analysis was utilized to determine the absolute risk reduction (ARR) needed in infection rate to make each dressing cost-effective. Results At $3.00, a single Xeroform+gauze is economically justified if the initial infection rate for TKA (1.10%) and THA (1.62%) are reduced by an ARR of 0.01% and 0.009%, respectively. Two to three additional post-operative dressing changes increases the cost of Xeroform+gauze to $9.00-12.00 and increases the required ARR for TKA to 0.04-0.05% and for THA to 0.028-0.038%. Mepilex Border costs $29.00 and requires an ARR of 0.11% for TKA and 0.09% for THA. Aquacel Ag costs $40.00 and requires an ARR of 0.16% for TKA and 0.13% for THA. Dermabond Prineo costs $79.00 and requires an ARR of 0.31% for TKA and 0.25% for THA. Variations in estimation of initial infection rate did not impact ARR for any dressing type. Conclusions Orthopaedic surgeons have multiple options for surgical dressings following total joint replacement. With respect to infection prophylaxis, Xeroform+gauze is the most cost-effective. Other specialized dressings such as Mepilex Border, Aquacel Ag, or Dermabond Prineo, require significantly higher reductions in infection rate to be economically justifiable.