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Background Proximal femoral replacements (PFRs) are often used in the setting of severe bone loss. As osteolysis has become less common, PFR may be used to address other causes of bone loss such as infection or periprosthetic fracture. The aim of this study is to investigate the clinical outcomes of PFR for non-neoplastic conditions. Methods A retrospective review of 46 patients undergoing PFR at a single institution was performed. The electronic records were reviewed to extract relevant information including the reason for use of PFR, surgical variables, follow-up, and complications. Survivorship curves were generated and differences in survivorship were evaluated using the log-rank test. Radiographic evaluation was also performed. Results Using revision as an endpoint, the Kaplan-Meier analysis of the entire cohort demonstrated a survival rate of 74% at 1 year and 67% at 5 years. Patients with a preoperative diagnosis of periprosthetic joint infection demonstrated the lowest survivorship with a failure rate of 47%. Furthermore, a high dislocation rate at 17.4% (n = 8) was observed. The use of dual-mobility articulation was effective in reducing dislocation. Conclusion PFR is a valuable reconstructive option for patients with massive proximal femoral bone loss. This study demonstrates that patients with periprosthetic joint infection who undergo PFR reconstruction are at very high risk of subsequent failure, most commonly from reinfection and instability. The use of a dual-mobility articulation in association with PFR appears to help mitigate risk of subsequent dislocation.

Fracture nonunion remains a devastating complication and may occur for several reasons, though the microbial contribution remains poorly estimated. Next-generation sequencing (NGS) techniques, including 16S rRNA gene profiling, are capable of rapid bacterial detection within clinical specimens. Nonunion cases may harbor microbes that escape detection by conventional culture methods that contribute to persistence. Our aim was to investigate the application of NGS pathogen detection to nonunion diagnosis.In this prospective multicenter study, samples were collected from 54 patients undergoing open surgical intervention for preexisting long-bone nonunion (n = 37) and control patients undergoing fixation of an acute fracture (n = 17). Intraoperative specimens were sent for dual culture and 16S rRNA gene-based microbial profiling. Patients were followed for evidence of fracture healing, whereas patients not healed at follow-up were considered persistent nonunion. Comparative analyses aimed to determine whether microbial NGS diagnostics could discriminate between nounions that healed during follow-up versus persistent nonunion.Positive NGS detection was significantly correlated with persistent nonunion, positive in 77% more cases than traditional culture. Nonunion cases were observed to have significantly increased diversity and altered bacterial profiles from control cases.NGS seems to be a useful adjunct in identification of organisms that may contribute to nonunion. Our findings suggest that the fracture-associated microbiome may be a significant risk factor for persistent nonunion. Ongoing work aims to determine the clinical implications of isolated organisms detected by sequencing and to identify robust microbial predictors of nonunion outcomes.Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Background: Antibiotic-loaded bone cement (ALBC) spacers are used in the first stage when treating periprosthetic joint infection (PJI). This study aimed to investigate whether a spacer made from commercial ALBC or plain bone cement with additional antibiotics could affect the spacer exchange rate before reimplantation. Methods: Patients undergoing two-stage exchange arthroplasty due to chronic PJI from January 2014 to August 2021 were retrospectively reviewed. The exclusion criteria included arthroplasty in the setting of septic arthritis, megaprosthesis, atypical pathogen infection, spacer placement unrelated to PJI, and spacer exchange due to mechanical complications. The patient demographics, brand of cement, and microbiology were recorded manually. The primary outcome was the incidence of spacer exchange due to persistent infection and the secondary outcome was the incidence of reinfection after reimplantation. A multivariate logistic regression analysis and Chi-square test were conducted to identify the effect of cement type on the spacer exchange. Results: A total of 334 patients underwent two-stage exchange arthroplasty for PJI. The spacer exchange rates in the commercial and non-commercial ALBC groups were 6.4% and 25.1%, respectively (p = 0.004). After controlling for confounding factors, there were significant differences between the commercial group and non-commercial groups in the spacer exchange rate (adjusted OR = 0.25; 95% CI = 0.72–0.87, p = 0.029). The use of commercial ALBC was not associated with a lower reinfection rate after reimplantation (p = 0.160). Conclusions: In a two-stage exchange arthroplasty scenario, the spacer comprised of commercial ALBC resulted in a lower spacer exchange rate than the plain bone cement, both of which had additional antibiotics. However, the use of commercial ALBC was not associated with a lower incidence of reinfection following reimplantation.

BACKGROUND Patient-reported allergies to aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) may preclude certain patients from receiving aspirin as venous thromboembolism (VTE) prophylaxis after total joint arthroplasty (TJA). The purpose of the study was to (1) determine whether the use of non-aspirin agents due to a self-reported aspirin or NSAID allergy was associated with a higher incidence of VTE and (2) determine the rate of true allergic reactions in patients who reported an allergy but still received aspirin. METHODS Prospectively collected data from 45,171 patients who underwent primary TJA between 2000 and 2019 were reviewed. Patients who reported an allergy to aspirin or NSAIDs were identified (n = 823). Using a validated VTE risk calculator, each patient was assigned a risk score based on 26 comorbidities. Bleeding complications, VTEs that occurred within 90 days postoperatively, and allergic reactions were collected as end points. Multivariable logistic regression was performed to determine the factors associated with VTE. RESULTS The overall incidence of aspirin or NSAID allergy was 1.8%. Only 80 of 267 patients (30%) reported an allergy to only aspirin and still received aspirin. Compared with patients who received aspirin without a history of allergy (n = 17,648), patients who received non-aspirin thromboprophylaxis due to allergy (n = 383) had a higher incidence of VTE (2.87% versus 0.24%, p < 0.001). On multivariable regression, these patients had an 8-fold increase in VTE risk (adjusted odds ratio, 7.94; 95% confidence interval, 2.86 to 22.07; p < 0.001). The incidence of true allergic reactions to aspirin among those with a reported allergy was 1.8% (number needed to harm = 55). No patients developed anaphylaxis or severe hypersensitivity reactions. CONCLUSIONS Patients with a self-reported allergy to aspirin or NSAIDs were at a significantly increased risk for VTE if they received non-aspirin thromboprophylaxis agents following TJA. Future research should evaluate the usefulness of preoperative allergy testing when selecting a VTE prophylactic agent in patients with self-reported allergies. LEVEL OF EVIDENCE Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Background Primary cutaneous gamma-delta T-cell lymphoma (PCγδTCL) and primary cutaneous aggressive epidermotropic T-cell lymphomas (PCAETCL) are rare aggressive cytotoxic cutaneous lymphomas (CyCL) often difficult to diagnose. Histopathologically, PCAETCL and PCγδTCL may resemble mycosis fungoides (MF) and the presence of adnexotropism in CyCL (CyCL) contributes to this diagnostic challenge, especially in the setting of atypical and double-negative phenotypes. Methods In this retrospective study clinical data and histopathological section of 91 patients were analyzed for signs of clinical and histopathological signs adnexotropism. Results Adnexotropism was identified in 48.4% (44/91) of cases, including PCAETCL (40.9%, 18/44), PCγδTCL and cytotoxic cutaneous lymphomas, not otherwise specified (CyCTCL, NOS) (43.2%, 19/44 and 15.9%, 7/44). Comparison between disease-related mortality with Kaplan-Meier survival analysis of non-adnexotropic vs adnexotropic CyCL did not show any significant difference between the two groups (P = 0.8). Clinically they present with patches, plaques, and tumors and commonly with ulceration, but follicular prominence or alopecia are rare. Clinical signs of adnexotropism such as alopecia and hypo- or anhidrosis were rarely seen. Conclusion Adnexotropism is a common finding in CyCL, especially in PCAETCL. Adnexotropic CyCL may be histopathologically difficult to distinguish from folliculotropic mycosis fungoides. A comprehensive IHC panel should be routinely performed in such cases.

It is our experience that parakeratosis with pagetosis is common in early melanoma when there is no history of trauma in the anatomical site. In lesions where the differential diagnosis includes dysplastic nevus (DN) and melanoma, we hypothesize that parakeratosis may be a marker for cases in which immunohistochemistry (IHC) may identify occult pagetosis. We performed a retrospective case–control study on cases with a histologic differential diagnosis of DN versus melanoma, including 423 cases with parakeratosis and 125 cases without parakeratosis. IHC staining (Mart-1 and/or Sox-10) was performed in all cases. The frequency of pagetosis and diagnostic upgrades in the cases versus the controls was calculated. The presence of parakeratosis was significantly associated with pagetosis (p

Background Patients with native joint septic arthritis are one of the highest risk groups for developing complications following total joint arthroplasty (TJA), especially periprosthetic joint infection(PJI). There is a paucity of information on the risk factors for developing PJI and the optimal treatment modality of the native septic joint that can mitigate that risk. This multicenter study aimed to determine these risk factors, including prior treatment. Methods A retrospective study of 233 TJAs performed, following prior septic arthritis at five institutions, was conducted. Comorbidities, organism profile, prior surgery, etiology of septic arthritis, and other relevant variables were reviewed. The primary outcome was the development of PJI, defined by Musculoskeletal Infection Society criteria. Bivariate and multivariate analyses were performed to identify risk factors for PJI. Results Overall, the PJI rate was 12.4% in patients who underwent TJA after native septic arthritis. Predisposing risk factors for PJI included antibiotic-resistant organisms, male gender, diabetes, and a postsurgical cause of septic arthritis eg open reduction internal fixation. When controlling for potential confounders, multivariate analysis revealed that male gender, diabetes, and a postoperative etiology were predictors of PJI. The definitive treatment modality for the septic joint did not affect the rate of PJI for both arthroscopy vs irrigation and debridement (I&D), and two-stage exchange vs single-stage procedure. Discussion This study has identified several risk factors for developing PJI in patients with prior septic joint arthritis, some of which are modifiable. The initial treatment modality of the native septic joint has no bearing on the development of PJI after TJA.

Drug-induced psoriasiform alopecia is an increasingly recognized form of alopecia mostly reported in association with TNF-alpha inhibitors. However, drug-induced psoriasiform alopecia in association with IL-17A inhibitors has not been described. We present a 62-year-old woman with severe psoriasis who developed new psoriatic plaques on the scalp with alopecia after initiating ixekizumab (anti-IL-17A). Scalp biopsy specimens revealed a non-cicatricial alopecia with increased telogen/catagen follicles, atrophy of the sebaceous glands, peribulbar and perifollicular inflammation with frequent lymphocytes, plasma cells, eosinophils, psoriasiform dermatitis, and lack of intra-corneal or intra-epidermal neutrophils. Overall, the clinical and histopathologic findings were most compatible with a drug-induced psoriasiform alopecia in association with IL-17A inhibitor therapy. Our case shows that drug-induced psoriasiform alopecia can paradoxically occur in patients on IL-17A inhibitor therapy and contributes to the growing list of cutaneous eruptions associated with biologic agents.

In vulvar biopsies, we have observed histopathologic abnormalities of elastic fibers identical to solar elastosis, with thick, curled, and irregular pale grey fibers in the dermis. In severe cases, changes resemble nodular solar elastosis. We retrospectively evaluated 238 vulvar biopsies with the goal of defining and characterizing changes of vulvar elastosis. Of 238 vulvar biopsies reviewed, 107 (45%) exhibited vulvar elastosis. Patients with vulvar elastosis were older (mean = 65 years old) compared to those without (mean = 44 years old). Sixty-six (62%) were graded as mild, 27 (25%) moderate, and 14 (13%) severe. Vulvar elastosis was significantly more common in women ≥45 years old (P-value < 0.001). There was moderate correlation between age and severity (correlation coefficient = 0.55, P-value < 0.001). Vulvar elastosis was observed in a variety of inflammatory and non-inflammatory pathologies. In 5 cases, the sole pathology was vulvar elastosis presenting clinically as either a pruritic or painful white to white-yellow papule or plaque, or vulvar pain or burning without a clinical lesion. Vulvar elastosis is a novel diagnostic entity occurring in a sun-protected site and its pathogenesis may be a degenerative phenomenon possibly related to advancing age and/or hormonal changes.

The aim of this study was to evaluate the diagnostic performance of minor criteria from the 2018 International Consensus Meeting (ICM) for the diagnosis of chronic periprosthetic joint infection (PJI) in an Asian population.We retrospectively reviewed 76 patients who underwent a revision knee or hip arthroplasty at an academic institution between September 2018 and December 2019. All major and minor 2018 ICM criteria were available for all patients included. Cases with at least 1 major criterion or score ≥6 in minor criteria were considered as infected. The diagnostic performance was evaluated by a receiver operative characteristic curve analysis and area under the curve (AUC) for each minor criterion. An AUC value of more than 0.9 was considered outstanding and 0.8-0.9 as excellent.When using 2018 ICM threshold, the diagnostic performance ranked based on AUC was the following: alpha defensin (0.92), positive histology (0.83), leukocyte esterase (0.82), synovial white blood cell (0.81), serum erythrocyte sedimentation rate (0.78), synovial polymorphonuclear neutrophils (0.77), serum C-reactive protein (0.74), D-dimer (0.59), single positive culture (0.53), and positive intraoperative purulence (0.51). Alpha defensin was considered as an outstanding test among the 2018 ICM minor criteria. Positive histology, leukocyte esterase, and synovial white blood cell were considered as excellent tests.Based on our findings, alpha-defensin has the best diagnostic performance in Asian population among the minor criteria of 2018 ICM.

Deep penetrating nevi (DPN) are dermal-based, heavily pigmented melanocytic proliferations primarily resulting from mutations in B-catenin and BRAF or, less commonly, NRAS. DPNs are considered to be intermediate grade tumors which are stable with low risk of malignant transformation. The precise risk for transformation is unknown. Only rare cases of DPN progressing to melanoma have been described. We present a case of a 53-year-old female with a blue-black thigh lesion, on histopathology illustrating a melanocytic proliferation with morphology most consistent with a DPN progressing to melanoma. Targeted next generation sequencing performed on both the atypical melanocytic proliferation and melanoma components showed NRAS and CTNNB1 mutations but no evidence of TERT promoter mutation or chromosomal copy number aberrations. The melanoma had additional mutations including a hotspot TERT promoter mutation as well as unbalanced chromosomal copy number aberrations. This report details the progression of DPN to melanoma through a prominent ultraviolet signature and acquisition of genetic aberrations. While the vast majority of DPNs are benign stable nevi, there are rare examples, which may progress to melanoma. This report documents a case and shows the molecular evolution by which the tumor transformed to melanoma.

Aims Failure of irrigation and debridement (I&D) for prosthetic joint infection (PJI) is influenced by numerous host, surgical, and pathogen-related factors. We aimed to develop and validate a practical, easy-to-use tool based on machine learning that may accurately predict outcome following I&D surgery taking into account the influence of numerous factors. Methods This was an international, multicentre retrospective study of 1,174 revision total hip (THA) and knee arthroplasties (TKA) undergoing I&D for PJI between January 2005 and December 2017. PJI was defined using the Musculoskeletal Infection Society (MSIS) criteria. A total of 52 variables including demographics, comorbidities, and clinical and laboratory findings were evaluated using random forest machine learning analysis. The algorithm was then verified through cross-validation. Results Of the 1,174 patients that were included in the study, 405 patients (34.5%) failed treatment. Using random forest analysis, an algorithm that provides the probability for failure for each specific patient was created. By order of importance, the ten most important variables associated with failure of I&D were serum CRP levels, positive blood cultures, indication for index arthroplasty other than osteoarthritis, not exchanging the modular components, use of immunosuppressive medication, late acute (haematogenous) infections, methicillin-resistant Staphylococcus aureus infection, overlying skin infection, polymicrobial infection, and older age. The algorithm had good discriminatory capability (area under the curve = 0.74). Cross-validation showed similar probabilities comparing predicted and observed failures indicating high accuracy of the model. Conclusion This is the first study in the orthopaedic literature to use machine learning as a tool for predicting outcomes following I&D surgery. The developed algorithm provides the medical profession with a tool that can be employed in clinical decision-making and improve patient care. Future studies should aid in further validating this tool on additional cohorts. Cite this article: Bone Joint J 2020;102-B(7 Supple B):11–19.

Background Antimicrobial-impregnated incise drapes are often used despite any literature that demonstrates a reduction in the rate of periprosthetic joint infection (PJI). The aim of this study is to compare the efficacy of antimicrobial-impregnated incise drapes with nonantimicrobial-impregnated incise drapes for the prevention of PJI in patients undergoing total joint arthroplasty (TJA). Methods A retrospective study of 9774 primary TJAs from 2000 to 2012 was performed. Patients who received an antimicrobial-impregnated incise drape (n = 5241) were compared with patients who received a nonantimicrobial-impregnated incise drape (n = 4533). The decision to use an antimicrobial drape was based on the surgeon’s discretion. Patients who developed PJI within 1 year after index surgery were identified. Multivariate logistic regression analysis and sensitivity analysis using propensity score matching were performed to control for potential confounders. Results The overall PJI rate was 1.14% (60 of 5241) for patients who received an antimicrobial-impregnated incise drape compared with 1.26% (57 of 4533) for those with a nonantimicrobial-impregnated incise drape. There was no difference in the PJI rate between patients with an antimicrobial-impregnated incise drape and those who received nonantimicrobial-impregnated incise drape in the univariate (odds ratio [OR] = 0.91; 95% confidence interval [CI] = 0.63-1.30), multivariate (adjusted OR = 0.92; 95% CI, 0.63-1.34), or propensity score matching analysis (OR = 0.84; 95% CI = 0.52-1.35). Conclusion Despite the increasing adoption of the use of antimicrobial-impregnated incise drapes in our institute, this study suggests that antimicrobial-impregnated incise drapes do not reduce PJI in patients undergoing primary TJAs.

Background Chronic renal failure (CRF) is an established risk factor for surgical site infection (SSI) and periprosthetic joint infection (PJI) after primary total joint arthroplasty. However, there is limited literature comparing outcomes between patients who receive dialysis vs renal transplantation. We examined and compared clinical outcomes of patients receiving dialysis vs those who had a prior renal transplantation. Methods We retrospectively identified 107 patients undergoing primary total joint arthroplasty between 2000 and 2017, who were receiving dialysis (n = 50), or had a prior renal transplantation (n = 57). The cohorts were compared with respect to postoperative complications, including 90-day SSI, PJI, and failure resulting in revision procedure. Multivariate analysis was performed to determine independent risk factors for complications and revision. Results A significantly higher rate of postoperative complications was seen in dialysis patients (28.0%) compared with renal transplant (7.1%). In particular, increased SSI and PJI rates were observed in dialysis group compared with the transplant cohort (18.0% vs 3.5%). In addition, increased revision rates (24.0% vs 3.5%) and decreased survivorship for the implant were observed in dialysis patients. Multivariate analysis revealed that patients with renal transplant were less likely to require revision arthroplasty and that total knee arthroplasty (vs total hip arthroplasty) was an independent risk factor for failure in dialysis patients. Conclusion This study provides further evidence that patients on dialysis who are on transplant list should await arthroplasty until transplant has taken place. In dialysis patients who are not transplant candidates, extreme care should be exercised, and additional strategies used to minimize the high complication rate that may be encountered.

Introduction Opioids remain the most prescribed medication after total hip arthroplasty (THA) despite the potential for abuse and adverse effects. Given the high rates of opioid abuse and potential adverse effects, the reporting of controlled substances is now mandatory in many statewide databases. This study aimed to use a mandatory statewide database to analyze opioid prescription patterns in postoperative THA patients and identify independent risk factors for those patients who need a second prescription and/or require prolonged use (>6 months). Methods We retrospectively reviewed a consecutive series of 619 primary THAs. Demographic and comorbidity information were collected for all patients. Narcotic prescription data (converted to morphine milligram equivalents) as well as prescription data for sedatives, benzodiazepines, and stimulants were collected from the State's Controlled Substance Monitoring websites 6 months before and 9 months after the index procedure. Bivariate and multivariate analyses were done for second prescription and continued use. Results Of the 619 patients who underwent THA, 34.9% (216/619) used preoperative opioids, 36.2% (224/619) filled a second opioid prescription, and 10.5% (65/619) had continued use past 6 months. Patients with preoperative opioids were at an approximately 4-fold increased odds of requiring a second script and 12 times odds of continued opioid use. In the multivariate analysis, independent risk factors for requiring a second prescription, in descending order of magnitude, included the use of any sedative or sleep aid prescription and preoperative narcotic use. Independent risk factors for continued narcotic use longer than 6 months after THA included preoperative narcotic use and increased length of stay. Discussion Several risk factors and their relative weight have been identified for continued narcotic consumption after THA. It is important for surgeons to consider these predisposing factors preoperatively during the informed consent process and for managing postoperative pain expectations.

Although aspirin has been adopted as an effective and safe prophylaxis against venous thromboembolism (VTE) by the arthroplasty community, the role of aspirin in the prevention of VTE in the setting of arthroplasty for trauma remains insufficiently known. Therefore, the present multicenter study investigated the efficacy of aspirin as VTE prophylaxis for patients with femoral neck fracture undergoing total hip arthroplasty or hemiarthroplasty.We reviewed the medical records of 1,141 patients with femoral neck fracture who underwent total hip arthroplasty or hemiarthroplasty from 2008 to 2018 at 3 different institutions. Data on patient demographic characteristics, body mass index, history of VTE, and comorbidities were obtained from an electronic chart query and were confirmed by reviewing the medical records manually. Patients were allocated to cohorts based on the type of prophylaxis administered: aspirin (n = 454) and other anticoagulants (n = 687). Patients were then propensity score-matched on the basis of the risk score calculated using a previously validated tool and the remaining confounding variables. The primary outcome was the development of symptomatic VTE, namely deep vein thrombosis (DVT) or pulmonary embolism (PE) confirmed by appropriate imaging, within 90 days after the surgical procedure. A bivariable analysis was performed.The overall VTE rate was 1.98% for patients who received aspirin compared with 6.7% for patients who received other anticoagulants (p0.001). After propensity score matching and regression modeling, aspirin was found to be noninferior to more potent anticoagulation in preventing VTE after both total hip arthroplasty and hemiarthroplasty.Aspirin is an effective option for VTE prophylaxis in patients with femoral neck fracture who undergo hip arthroplasty. Based on the patient management benefits of aspirin for elective arthroplasty and the present study, we suggest its use in standard-risk ambulatory patients.Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Background Diagnosing acute periprosthetic joint infection remains a challenge. Several studies have proposed different acute cutoffs resulting in the International Consensus Meeting recommending a cutoff of 100 mg/L, 10,000 cell/μL and 90% for serum C-reactive protein (CRP), synovial white blood cell count (WBC), and polymorphonuclear percentage (PMN%), respectively. However, establishing cutoffs are difficult as the control group is limited to rare early aseptic revisions, and performing aspiration in asymptomatic patients is difficult because of a fear of seeding a well-functioning joint arthroplasty. This study (1) assessed the sensitivity of current thresholds for acute periprosthetic joint infection (PJI) and (2) identified associated factors for false negatives. Methods We retrospectively reviewed patients with acute PJIs (n = 218), defined as less than 6 weeks from index arthroplasty, treated between 2000 and 2017. Diagnosis of PJI was based on 2 positive cultures of the same pathogen from the periprosthetic tissue or synovial fluid samples. Sensitivities of International Consensus Meeting cutoff values of CRP, synovial WBC, and PMN% were evaluated according to organism type. Multiple logistic regression analysis was performed to determine associated factors for false negatives. Results Overall, the sensitivity of CRP, synovial WBC, and PMN% for acute PJI was 55.3%, 59.6%, and 50.5%, respectively. Coagulase-negative Staphylococcus (CNS) demonstrated the lowest sensitivity for both CRP (37.5%) and WBC (55.6%). CNS infection was identified as an independent risk factor for false-negative CRP. Conclusions Current thresholds for acute PJI may be missing approximately half of PJIs. Low virulent organisms, such as CNS, may be responsible for these false negatives. Current thresholds for acute PJI must be reexamined.

Background:. A megaprosthesis may be used for reconstruction in patients with massive bone loss or a periprosthetic fracture. Periprosthetic joint infection (PJI) may occur after a megaprosthesis reconstruction and may pose a major challenge. The outcomes of managing PJI in patients with a megaprosthesis is relatively unclear. The aim of this study was to investigate the clinical course and outcomes of PJI in patients with a megaprosthesis in place. Methods:. From a total of 219 patients who underwent megaprosthesis replacement for non-oncologic conditions, 38 (17.4%) developed subsequent PJI. A retrospective review of the medical record was performed to ascertain the course of the PJI and treatment outcomes. Kaplan-Meier analysis was performed to evaluate the survival function, and the log-rank test was used to assess differences in outcome measures. Results:. The surgical management of 33 patients with PJI included debridement, antibiotics, and implant retention (DAIR) (82%), consisting of DAIR with modular component exchange (19 patients) and DAIR without component exchange (8 patients); 2-stage exchange arthroplasty (9%); resection arthroplasty (6%); and a single-stage revision arthroplasty (3%). The Kaplan-Meier survivorship analysis demonstrated that the overall survival rate was 65.1% at 2 years. The mortality rate was 15%, with many patients undergoing salvage procedures including amputation (18%), arthrodesis (6%), and resection arthroplasty (6%). Conclusions:. The rate of PJI after megaprosthesis reconstruction, 17% in this study, appears to be very high. The management of PJI in these patients is challenging, with 1 of 3 patients undergoing failed treatment. Despite the limited options available, DAIR seems to be an appropriate treatment strategy for some of these patients. Further data on a larger cohort are needed to assess the success of various surgical procedures and predictors of failure in this challenging patient population. Level of Evidence:. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

The use of extended antibiotic (EA) prophylaxis (> 24 h) remains controversial in aseptic revision arthroplasty. We sought to determine whether EA prophylaxis reduces the risk of periprosthetic joint infection (PJI) in aseptic revision hip and knee arthroplasty. A total of 2800 patients undergoing aseptic revision hip and knee arthroplasty at five institutional databases from 2008 to 2017 were evaluated. One to two nearest-neighbor propensity score matching analysis was conducted between patients who did and did not receive extended antibiotic prophylaxis. The matching elements included age, sex, body mass index, Charlson comorbidity index, hospital distribution, year of surgery, joint (hip or knee), surgical time, CRP, preoperative hemoglobin, albumin, and length of stay. The primary outcome was the development of PJI, which was assessed at 30 days, 90 days, and 1 year following revision and analyzed separately. A total of 2467 (88%) patients received EA prophylaxis, and 333 (12%) patients received standard antibiotic (SA) prophylaxis (≤ 24 h). In the propensity-matched analysis, there was no difference between patients who received EA prophylaxis and those who did not in terms of 30-day PJI (0.3% vs. 0.3%, p = 1.00), 90-day PJI (1.7% vs. 2.1%, p = 0.62) and 1- year PJI (3.8% vs. 6.0%, p = 0.109). For revision hip, the incidence of PJI was 0.2% vs 0% at 30 days (p = 0.482), 1.6% vs 1.4% at 90 days (p = 0.837), and 3.4% vs 5.1% at 1 year (p = 0.305) in the EA and SA group. For revision knee, the incidence of PJI was 0.4% vs 0.9% at 30 days (p = 0.63), 1.8% vs 3.4% at 90 days (p = 0.331), and 4.4% vs 7.8% at 1 year (p = 0.203) in the EA and SA group. A post hoc power analysis revealed an adequate sample size with a beta value of 83%. In addition, the risks of Clostridium difficile and resistant organism infection were not increased. This multi-institutional study demonstrated no difference in the rate of PJIs between patients who received extended antibiotic prophylaxis and those who did not in aseptic revision arthroplasty. The risk of C. difficile and resistant organism infection was not increased with prolonged antibiotic use.

Prosthetic joint infection (PJI) is a complication after arthroplasty that negatively affects patient health. However, prior reports have not addressed the long-term consequences of hip PJI in terms of patient mortality, quality of life, and hip function.At a minimum of 10 years after PJI in patients undergoing primary THA, in the context of several large, national databases in Sweden, we asked: (1) Is mortality increased for patients with PJI after THA compared with patients with a noninfected THA? (2) Does PJI of the hip have a negative influence on quality of life as measured by the Euro-QoL-5D-5L (EQ-5D-5L), ambulatory aids, residential status, and hip function as measured by the Oxford Hip Score (OHS)? (3) Which factors are associated with poor patient-reported outcome measures (PROMs) for patients with PJI after primary THA?This study included 442 patients with a PJI after primary THA, from a previously published national study, including all patients with a THA performed from 2005 to 2008 in Sweden (n = 45,570) recruited from the Swedish Hip Arthroplasty Registry (SHAR). Possible deep PJIs were identified in the Swedish Dispensed Drug Registry and verified by review of medical records. Mortality in patients with PJI was compared with the remaining cohort of 45,128 patients undergoing primary THA who did not have PJI. Mortality data were retrieved from the SHAR, which in turn is updated daily from the population registry. A subgroup analysis of patients who underwent primary THA in 2008 was performed to adjust for the effect of comorbidities on mortality, as American Society of Anesthesiologists (ASA) scores became available in the SHAR at that time. For the PROM analysis, we identified three controls matched by age, gender, indication for surgery, and year of operation to each living PJI patient. A questionnaire including EQ-5D-5L, ambulatory aids, residential status, and OHS was collected from patients with PJI and controls at a mean of 11 years from the primary procedure. Apart from age and gender, we analyzed reoperation data (such as number of reoperations and surgical approach) and final prosthesis in situ to explore possible factors associated with poor PROM results.After controlling for differences in sex, age, and indication for surgery, we found the all-cause 10-year mortality higher for patients with PJI (45%) compared with patients undergoing THA without PJI (29%) (odds ratio 1.4 [95% CI 1.2 to 1.6]; p0.001). The questionnaire, with a minimum of 10 years of follow-up, revealed a lower EQ-5D-5L index score (0.83 versus 0.94, -0.13 [95% CI -0.18 to -0.08; p0.001]), greater proportion of assisted living (21% versus 12%, OR 2.0 [95% CI 1.2 to 3.3]; p = 0.01), greater need of ambulatory aids (65% versus 42%, OR 3.1 [95% 2.1 to 4.8]; p0.001), and a lower OHS score (36 versus 44, -5.9 [-7.7 to -4.0]; p0.001) for patients with PJI than for matched controls. Factors associated with lower OHS score for patients with PJI were three or more reoperations (-8.0 [95% CI -13.0 to -3.2]; p = 0.01) and a direct lateral approach used at revision surgery compared with a posterior approach (-4.3 [95% CI -7.7 to -0.9]; p = 0.01).In this study, we found that PJI after THA has a negative impact on mortality, long-term health-related quality of life, and hip function. Furthermore, the subgroup analysis showed that modifiable factors such as the number of reoperations and surgical approach are associated with poorer hip function. This emphasizes the importance of prompt, proper initial treatment to reduce repeated surgery to minimize the negative long-term effects of hip PJI.Level III, therapeutic study.

Background Interim spacer exchange may be performed in patients undergoing 2-stage exchange for periprosthetic joint infection. Several studies have demonstrated that interim spacer exchange is associated with poor outcomes. This study investigated the survivorship and risk factors for failure in patients with an interim spacer exchange. Methods Two institutional databases identified 182 patients who underwent spacer exchange from 2000 to 2017. Primary outcomes included progression to reimplantation, treatment success, and mortality. Bivariate analysis was performed to evaluate risk factors associated with failure. Kaplan-Meier curves using host and local grades were generated to evaluate for primary outcomes and differences in survivorship. Results The overall failure rate was 49% in patients with a spacer exchange. Most patients (60%) failed before 2 years. Higher comorbidity scores, elevated erythrocyte sedimentation rate, and non-White race were more prevalent in patients who failed. Negative cultures at the time of exchange were more prevalent in patients who did not fail. Failure rate was higher in immunocompromised conditions, and those who had revision prior to exchange. After considering clinically relevant variables, advanced host grade C was the single factor associated with treatment failure. Although survivorship curves were not significantly different between extremity local grades, higher host grades were associated with treatment failure. Conclusion Almost 1 out of 2 patients with spacer exchange were found to fail the intended 2-stage revision arthroplasty. Benefits of delivering additional antibiotic load with a new spacer should be balanced against poor outcomes in patients with the aforementioned risk factors.

Background:. Patients undergoing total joint arthroplasty (TJA) following septic arthritis are at higher risk for developing periprosthetic joint infection (PJI). Minimal literature is available to guide surgeons on the optimal timing of TJA after completing treatment for prior native joint septic arthritis. This multicenter study aimed to determine the optimal timing of TJA after prior septic arthritis and to examine the role of preoperative serology in predicting patients at risk for developing PJI. Methods:. A total of 207 TJAs were performed after prior septic arthritis from 2000 to 2017 at 5 institutions. Laboratory values, prior treatment, time from the initial infection, and other variables were recorded. Bivariate analyses were performed to identify the association between the time from septic arthritis to TJA and the risk of developing subsequent PJI. A subanalysis was performed between patients who underwent TJA in 1 setting (n = 97) compared with those who underwent 2-stage arthroplasties (n = 110). Receiver operating characteristic (ROC) curve analysis was performed for serum markers prior to TJA in predicting the risk of a subsequent PJI. Results:. The overall PJI rate was 12.1%. Increasing time from septic arthritis treatment to TJA was not associated with a reduction of PJI, whether considering time as a continuous or categorical variable, for both surgical treatment cohorts (all p > 0.05). Although the ROC curve analysis found that the optimal threshold for timing of TJA from the initial treatment was 5.9 months, there was no difference in the PJI rate when the overall cohort was dichotomized by this threshold and when stratified by 1-stage compared with 2-stage TJA. There was no significant difference in erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) level prior to conversion TJA between patients who subsequently developed PJI and those who did not. Conclusions:. Serum markers have limited value in predicting subsequent PJI in patients who undergo TJA after prior septic arthritis. There was no optimal interim period between septic arthritis treatment and subsequent TJA; thus, delaying a surgical procedure does not appear to reduce the risk of PJI. Level of Evidence:. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Background Multiple studies have demonstrated that ketamine, a glutamate receptor blocker, may decrease postoperative pain in abdominal and orthopedic surgeries. However, its role with spinal anesthesia and total knee arthroplasty (TKA) remains unknown. The purpose of this study is to determine the efficacy of subanesthetic dosing of ketamine during TKA on postoperative pain and narcotic consumption. Methods In this prospective, randomized, double-blinded clinical trial, we enrolled 91 patients undergoing primary TKA with spinal anesthesia in a single institution from 2017 to 2018. Patients were randomized to receive intraoperative ketamine infusion at a rate of 6 mcg/kg/min for 75 minutes or a saline placebo. All patients received spinal anesthesia and otherwise identical surgical approaches, pain management, and rehabilitation protocols. Patient-reported visual analog pain scores were calculated preoperatively, postoperative days (POD) 0-7, and 2 weeks. Narcotic consumption was evaluated on POD 0 and 1. Results There was no difference in average pain between ketamine and placebo at all time points except for at PODs 1 (45 vs 56, P = .041) and 4 (39 vs 49, P = .040). For least pain experienced, patients administered with ketamine experienced a reduction in pain only at POD 4 (22 vs 35, P = .011). There was no difference in maximum pain cohorts at all time points of the study or in-hospital morphine equivalents between the 2 cohorts. Conclusion As part of multimodal pain management protocol, intraoperative ketamine does not result in a clinically significant improvement in pain and narcotic consumption following TKA.

Aims Unicompartmental knee arthroplasty (UKA) provides improved early functional outcomes and less postoperative morbidity and pain compared with total knee arthroplasty (TKA). Opioid prescribing has increased in the last two decades, and recently states in the USA have developed online Prescription Drug Monitoring Programs to prevent overprescribing of controlled substances. This study evaluates differences in opioid requirements between patients undergoing TKA and UKA. Patients and Methods We retrospectively reviewed 676 consecutive TKAs and 241 UKAs. Opioid prescriptions in morphine milligram equivalents (MMEs), sedatives, benzodiazepines, and stimulants were collected from State Controlled Substance Monitoring websites six months before and nine months after the initial procedures. Bivariate and multivariate analysis were performed for patients who had a second prescription and continued use. Results Patients undergoing UKA had a second opioid prescription filled 50.2% of the time, compared with 60.5% for TKA (p = 0.006). After controlling for potential confounders, patients undergoing UKA were still less likely to require a second prescription than those undergoing TKA (adjusted odds ratio (OR) 0.58, 95% confidence interval (CI) 0.42 to 0.81; p = 0.001). Continued opioid use requiring more than five prescriptions occurred in 13.7% of those undergoing TKA and 5.8% for those undergoing UKA (p = 0.001), and was also reduced in UKA patients compared with TKA patients (adjusted OR 0.33, 95% CI 0.16 to 0.67; p = 0.022) in multivariate analysis. The continued use of opioids after six months was 11.8% in those undergoing TKA and 8.3% in those undergoing UKA (p = 0.149). The multivariate models for second prescriptions, continued use with more than five, and continued use beyond six months yielded concordance scores of 0.70, 0.86, and 0.83, respectively. Conclusion Compared with TKA, patients undergoing UKA are less likely to require a second opioid prescription and use significantly fewer opioid prescriptions. Thus, orthopaedic surgeons should adjust their patterns of prescription and educate patients about the reduced expected analgesic requirements after UKA compared with TKA. Cite this article: Bone Joint J 2019;101-B(7 Supple C):22–27

BACKGROUND Premature desquamation of the inner root sheath (PDIRS) is considered one of the distinctive features in central centrifugal cicatricial alopecia (CCCA). However, PDIRS can be seen in other alopecia subtypes, and its utility in the diagnosis of CCCA has been debated. We aimed to examine a large cohort of alopecia cases for the presence of PDIRS in association with and without inflammation to determine whether PDIRS in noninflamed follicles can be used as a specific marker of CCCA. METHODS Retrospective analysis was performed on 501 histologically unambiguous cases of alopecia (111 of CCCA, 102 of lichen planopilaris, 62 of discoid lupus erythematosus, 16 of acne keloidalis nuchae, 27 of folliculitis decalvans, 80 of androgenetic alopecia, 97 of alopecia areata, and 6 of psoriatic alopecia). The frequency of PDIRS, including cases with and without inflammation, was determined. RESULTS PDIRS was identified in all alopecia subtypes evaluated. When PDIRS was identified in lichen planopilaris, discoid lupus erythematosus, acne keloidalis nuchae, and alopecia areata, 100% of cases were in inflamed follicles. PDIRS in noninflamed follicles occurred in 73% (81/111) of CCCA, 33% (2/6) of psoriatic alopecia, 11% (3/27) of folliculitis decalvans, and 1% (1/97) of androgenetic alopecia. The presence of PDIRS in at least one noninflamed hair follicle correlated with a diagnosis of CCCA with a sensitivity of 73% and a specificity of 98% (P-value

Based on current guidelines from the American Academy of Orthopaedic Surgeons (AAOS), a number of prophylactic modalities for the prevention of venous thromboembolism in total joint arthroplasty may be used. It is common practice that more potent prophylactic agents are used for patients at higher risk of venous thromboembolism. However, we are aware of no studies that have investigated the efficacy of potent anticoagulation in higher-risk individuals. Therefore, the purpose of our study was to test the hypothesis that low-molecular-weight heparin and warfarin result in a reduction in venous thromboembolism events in high-risk patients.A retrospective, multi-institutional study of 60,467 primary and revision total joint arthroplasties from 2000 to 2015 was performed. Identified medications were classified as aspirin, low-molecular-weight heparin, or warfarin. Patients with unavailable venous thromboembolism prophylaxis information or those not receiving the aforementioned prophylaxis were excluded. Information pertinent to the objective of this study was collected and a venous thromboembolism risk score was calculated based on 26 variables. Treatment outcomes assessed included 90-day rate of symptomatic venous thromboembolism and periprosthetic joint infection. Propensity score matching was performed (1:1), as well as logistic regression analysis on the total sample.Aspirin prophylaxis demonstrated a lower rate of deep vein thrombosis, pulmonary embolism, and venous thromboembolism than warfarin and low-molecular-weight heparin alone throughout all risk scores. In the matched propensity score analysis, low-molecular-weight heparin and warfarin demonstrated increased odds of venous thromboembolism for both standard-risk and high-risk patients undergoing total knee arthroplasties compared with aspirin. For primary total hip arthroplasty, warfarin demonstrated an increased risk for high-risk patients and low-molecular-weight heparin demonstrated an increased risk for standard-risk patients. The prevalence of periprosthetic joint infection was higher in patients receiving warfarin (p0.001 for both comparisons of warfarin with aspirin and low-molecular-weight heparin).The results of this multi-institutional study demonstrate that the use of warfarin and low-molecular-weight heparin in higher-risk patients does not necessarily result in a reduction in symptomatic venous thromboembolism. Aspirin administered to higher-risk patients seems to be as effective as potent anticoagulation and more effective than warfarin.Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Current guidelines recommend serum erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) as the first-line testing for evaluation of suspected periprosthetic joint infection, in addition to synovial white blood-cell (WBC) count and polymorphonuclear percentage. However, the sensitivity and other diagnostic measures of these tests using a standardized definition of periprosthetic joint infection and the influence of organisms on these inflammatory markers remain inadequately investigated.A retrospective review of an institutional database of 549 periprosthetic joint infection cases and 653 aseptic total joint arthroplasty revisions was performed. Periprosthetic joint infection was defined using major criteria from the International Consensus Meeting (ICM) on Periprosthetic Joint Infection. The mean inflammatory marker levels were compared among organisms with Student t tests and the proportions of elevated laboratory levels were compared among organisms with chi-square analyses. Receiver operating characteristic curve analyses were performed to calculate new cutoffs, sensitivities, and specificities for each organism and overall for serum CRP and ESR and synovial WBC and polymorphonuclear percentage.The sensitivity of these markers for diagnosing chronic periprosthetic joint infection was 0.85 for ESR, 0.88 for CRP, 0.83 for WBC count, and 0.78 for polymorphonuclear percentage. For ESR, antibiotic-resistant organisms had higher mean values (84.3 mm/hr) than culture-negative cases (57.4 mm/hr), coagulase-negative Staphylococcus (68.3 mm/hr), and Streptococcus species (66.1 mm/hr); Staphylococcus aureus (81.0 mm/hr) was higher than culture-negative cases (57.4 mm/hr). For CRP, culture-negative cases had lower mean values (41.0 mg/L) than gram-negative organisms (87.4 mg/L), antibiotic-resistant organisms (86.0 mg/L), S. aureus (112.2 mg/L), and Streptococcus species (114.6 mg/L); S. aureus (112.2 mg/L) was higher than coagulase-negative Staphylococcus (66.0 mg/L). For WBC count, culture-negative cases had lower mean values (27,984.5 cells/mL) than S. aureus (116,250.0 cells/mL) and Streptococcus species (77,933.7 cells/mL). For polymorphonuclear percentage, there were no significant differences in mean values among all organisms.It appears that serological markers, namely ESR and CRP, have a higher false-negative rate than previously reported. Synovial markers similarly exhibit high false-negative rates. Furthermore, the sensitivity of these tests appears to be related to organism type. Surgeons should be aware of the high rate of false-negatives associated with low-virulence organisms and culture-negative cases.Diagnostic Level I. See Instructions for Authors for a complete description of levels of evidence.

Opioids are used for pain control after total knee arthroplasty (TKA) and carry risk for abuse. Mandatory statewide databases have been created to monitor their use. The goal of this study was to identify patient risk factors for prolonged opioid use after TKA. The authors retrospectively reviewed a consecutive series of 676 primary TKA procedures performed between January 2017 and July 2017. Information on fulfillment of narcotic, sedative, benzodiazepine, and stimulant prescriptions was obtained from the Pennsylvania State Controlled Substance Monitoring website 6 months before and 1 year after the procedure. Bivariate and multivariate analyses were used to identify risk factors for the need for a second prescription and opioid use for longer than 6 months. Of this cohort, 30.3% used preoperative opioids, 60.5% filled a second opioid prescription, and 11.8% continued opioid use for longer than 6 months. Patients who had opioid use before the index procedure had more than 3-fold (odds ratio [OR], 3.29; P P Orthopedics . 2021;44(1):e50–e54.]

Background Recent studies suggest an increased risk for periprosthetic joint infection (PJI) utilizing the direct anterior (DA) approach to the hip. The purpose of this study was to investigate whether such an increased risk does indeed exist on a large cohort of patients, operated by experienced surgeons and taking into account various confounders. Methods This was a single institutional study, including all patients who underwent primary total hip arthroplasty during the last decade, who were operated on by four high-volume arthroplasty surgeons utilizing a single surgical approach. Three of them utilized the direct lateral (DL) approach while one of them used the DA approach throughout the entire study. Patient characteristics, demographics, and comorbidities were assessed as well as operative and perioperative factors and their association with PJI. Association between surgical approach and PJI was evaluated in a univariate followed by a multivariate regression analysis. Results A total of 10,201 patients were included in the study. Of those, 4390 (43.0%) underwent total hip arthroplasty through the DA approach and 5811 (57.0%) through the DL approach. PJI rates were 0.9% (38/4390) in the DA group compared with 1.3% (73/5811) in the DL group (P = .068). Results from a regression analysis showed no significant association between PJI and DA approach (adjusted odds ratio 0.760, 95% confidence interval 0.428-1.348, P = .348). The risk remained nonsignificant in patients with higher body mass index. There were also no significant differences in the infecting organisms between the two groups. Conclusion The DA approach to the hip does not increase the risk for subsequent PJI.

Background The optimal type of dressing in the setting of total joint arthroplasty (TJA) remains uncertain. The aim of this network meta-analysis was to compare various wound dressings and identify the optimal type of dressings for blister reduction and prevention of periprosthetic joint infection (PJI) in patients after TJA. Methods Studies comparing 2 or more dressing groups after TJA (hip or knee) were systematically searched on PubMed, Embase, and Scopus. Two authors performed the study selection, risk of bias assessment, and data extraction. Both outcomes were assessed using odds ratios (OR) with 95% confidence intervals (CI) and were ranked using surface under the cumulative ranking curve (SUCRA) probabilities to determine a hierarchy of dressings. A sensitivity analysis was performed to reduce the effect of intransitivity between studies. Results A total of 21 studies, consisting of 12 dressing types in 7293 TJAs, were included in the final analysis. The highest incidence of blisters occurred when using negative-pressure wound therapy (OR 9.33, 95% CI 3.51-24.83, vs gauze). All dressings ranked better than gauze in infection rate except for hydrofiber (OR 1.46, 95% CI 0.02-112.53) and fabric dressings (OR 1.46, 95% CI 0.24-9.02). For blister reduction, alginate (SUCRA = 87.7%) and hydrofiber with hydrocolloid (SUCRA = 92.3%) were ranked as the optimal dressings before and after a sensitivity analysis, respectively. Antimicrobial dressing (SUCRA = 83.7%) demonstrated the most efficacy for preventing PJI. Conclusion Based on the evidence from our analysis, an antimicrobial dressing is the optimal dressing to prevent PJI. If negative-pressure wound therapy is used, surgeons should be aware of an increased incidence of blister formation. Further studies should focus on the alginate versus hydrofiber and hydrocolloid dressing to determine the optimal dressing to reduce blisters.

Background The diagnosis of periprosthetic joint infection (PJI) in the early postoperative period remains a challenge. Although studies have established that serum C-reactive protein (CRP) and synovial markers may be useful, recent studies have suggested that the current thresholds used may lack sensitivity. The purpose of this study was to examine the role of serum CRP, erythrocyte sedimentation rate (ESR), synovial fluid white blood-cell (WBC) count, and polymorphonuclear neutrophil (PMN) percentage in the diagnosis of acute postoperative PJI and to identify the optimal threshold. Methods This multicenter study included patients who were investigated for possible PJI within 90 days of an index arthroplasty. This study included 197 patients from 4 institutions who underwent total joint arthroplasty from 2000 to 2017. Of these patients, 123 were confirmed to have PJI, and 74 were ruled out as not having PJI (non-infected group). Analyses of receiver operating characteristic (ROC) curves and the area under the curve were performed to determine the value of each test and optimal cutoff values. Results The optimal cutoff value was 6,130 cells/μL for synovial fluid WBC count (91% sensitivity and 83% specificity), 39.8 mg/L for serum CRP (91% sensitivity and 87% specificity), 39.5 mm/hr for ESR (76% sensitivity and 67% specificity), and 79.5% for PMN percentage (95% sensitivity and 59% specificity). Reducing the acute period from 90 days to 30 days or 45 days made little difference in most threshold values. However, the optimal cutoff for synovial fluid WBC count was almost twice as high (10,170 cells/μL) when using a 30-day definition instead of a 90-day definition. Conclusions The calculated cutoffs in our study were substantially lower than the thresholds used by the Musculoskeletal Infection Society. The calculated values of this study should be used, as previous cutoffs may be too high and lack sensitivity. In addition, it appears that the threshold values, at least for some of the tests, change as the duration since the index arthroplasty lengthens. A continuum of threshold values that is dependent on the number of days since the index arthroplasty may need to be used for the diagnosis of acute PJI. Level of evidence Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Returning to work after surgery is a primary concern of patients who are contemplating total joint arthroplasty (TJA). The ability to return to work has enormous influence on the patient's independence, financial well-being, and daily activities. The goal of this study was to determine the independent patient variables that predict return to work as well as to create a predictive model. From June 2017 to December 2017, a total of 391 patients who underwent primary TJA (243 hips, 148 knees) were prospectively enrolled in the study to obtain information on return to work after surgery. Patients were sent a series of questions in a biweekly survey. Information was collected on the physical demands of their occupation, the number of hours spent standing, the limitations to return to work, and the use of assistive devices. Bivariate analysis was performed, and a multiple linear regression model was created. Most (89.6%) patients returned to work within 12 weeks of surgery. Patients who underwent total hip arthroplasty returned to work earlier than those who underwent total knee arthroplasty (5.56 vs 7.79 weeks, respectively). Analysis showed the following independent predictors for faster return to work: self-employment, availability of light-duty work, male sex, and higher income. Predictors for slower return to work included a physically demanding occupation (at least 50% physical duties), knee arthroplasty, longer length of stay, and a job requiring more hours spent standing. This model reported an adjusted R 2 of 0.332. The findings provide an objective predictive model of the patient- and procedure-specific characteristics that affect postoperative return to work. Surgeons should consider these factors when counseling patients on their postoperative expectations. [ Orthopedics . 2020;43(5):e415–e420.]