Extended Prophylactic Antibiotics for Primary and Aseptic Revision Total Joint Arthroplasty: A Meta-Analysis.

BACKGROUND: There is growing interest in extended antibiotic prophylaxis (EAP) following total joint arthroplasty (TJA); however, the benefit of EAP remains controversial. For this investigation, both oral and intravenous antibiotic protocols were included in the EAP group. METHODS: The Cochrane Database of Systematic Reviews, Cochrane Register of Controlled Trials, PubMed, MEDLINE, Web of Science, Ovid Embase, Elton B. Stephens CO, and Cumulative Index to Nursing and Allied Health Literature were queried for literature comparing outcomes of primary and aseptic revision total hip arthroplasty (THA) and total knee arthroplasty (TKA) patients who were treated with either ≤24 hours of postoperative antibiotic prophylaxis (standard of care [SoC]) or >24 hours of EAP. The primary outcome was periprosthetic joint infection (PJI). A pooled relative-risk random-effects Mantel-Haenszel model was implemented to compare cohorts. RESULTS: There were 18 studies with a total of 19,153 patients included. There was considerable variation in antibiotic prophylaxis protocols with first-generation cephalosporins being the most commonly implemented antibiotic for both groups. Patients treated with EAP were 35% less likely to develop PJI relative to the SoC (P = .0004). When examining primary TJA, patients treated with EAP were 39% and 40% less likely to develop a PJI for TJA (P = .0008) and THA (P = .02), respectively. There was no significant difference for primary TKA (P = .17). When examining aseptic revision TJA, EAP led to a 36% and 47% reduction in the probability of a PJI for aseptic revision TJA (P = .007) and aseptic revision TKA (P = .008), respectively; there was no observed benefit for aseptic revision THA (P = .36). CONCLUSIONS: This meta-analysis demonstrated that patients treated with EAP were less likely to develop a PJI relative to those treated with the SoC for all TJA, primary TJA, primary THA, aseptic revision TJA, and aseptic revision TKA. There was no significant difference observed between EAP and SoC for primary TKA or aseptic revision THA.

Chat Generative Pretrained Transformer (ChatGPT) and Bard: Artificial Intelligence Does not yet Provide Clinically Supported Answers for Hip and Knee Osteoarthritis.

BACKGROUND: Advancements in artificial intelligence (AI) have led to the creation of large language models (LLMs), such as Chat Generative Pretrained Transformer (ChatGPT) and Bard, that analyze online resources to synthesize responses to user queries. Despite their popularity, the accuracy of LLM responses to medical questions remains unknown. This study aimed to compare the responses of ChatGPT and Bard regarding treatments for hip and knee osteoarthritis with the American Academy of Orthopaedic Surgeons (AAOS) Evidence-Based Clinical Practice Guidelines (CPGs) recommendations. METHODS: Both ChatGPT (Open AI) and Bard (Google) were queried regarding 20 treatments (10 for hip and 10 for knee osteoarthritis) from the AAOS CPGs. Responses were classified by 2 reviewers as being in "Concordance," "Discordance," or "No Concordance" with AAOS CPGs. A Cohen's Kappa coefficient was used to assess inter-rater reliability, and Chi-squared analyses were used to compare responses between LLMs. RESULTS: Overall, ChatGPT and Bard provided responses that were concordant with the AAOS CPGs for 16 (80%) and 12 (60%) treatments, respectively. Notably, ChatGPT and Bard encouraged the use of non-recommended treatments in 30% and 60% of queries, respectively. There were no differences in performance when evaluating by joint or by recommended versus non-recommended treatments. Studies were referenced in 6 (30%) of the Bard responses and none (0%) of the ChatGPT responses. Of the 6 Bard responses, studies could only be identified for 1 (16.7%). Of the remaining, 2 (33.3%) responses cited studies in journals that did not exist, 2 (33.3%) cited studies that could not be found with the information given, and 1 (16.7%) provided links to unrelated studies. CONCLUSIONS: Both ChatGPT and Bard do not consistently provide responses that align with the AAOS CPGs. Consequently, physicians and patients should temper expectations on the guidance AI platforms can currently provide.

Do Patients with Paget's Disease Have Worse Outcomes following Primary Total Knee Arthroplasty?

Well-powered studies evaluating the effects of Paget's disease on patient outcomes following primary total knee arthroplasty (TKA) are limited. The objective of this study was to determine whether Paget's disease patients undergoing primary TKA have higher rates of complications. A query of an administrative database was performed identifying Paget's disease patients undergoing primary TKA as the study cohort. Patients who did not have Paget's disease served as a matching cohort. Study group patients were matched in a 1:5 ratio by age, sex, and comorbidities. The query yielded 34,284 patients in the study (n = 5,714) and matched (n = 28,570) cohorts. Outcomes analyzed included length of stay (LOS), costs of care, 90-day medical and surgical complications, and 2-year implant-related complications. Multivariate logistic regression analyses were used to calculate the odds ratios (ORs) of complications. Paget's disease patients undergoing primary TKA were found to have significantly longer in-hospital LOS (4 vs. 3 days, p < 0.0001). Study group patients incurred significantly higher 90-day episode-of-care costs ($15,124.55 vs. $14,610.01, p < 0.0001). Additionally, Paget's disease patients were found to have higher incidences and odds of medical/surgical (25.93 vs. 13.58%; OR: 1.64, p < 0.0001) and implant-related complications (8.97 vs. 5.02%; OR: 1.71, p < 0.0001). Specifically, Paget's disease patients were more likely to have periprosthetic fractures, mechanical loosening, and revision TKAs (p < 0.0001). This study demonstrated that Paget's disease was associated with longer in-hospital LOS, increased costs, and higher rates of complications. The study can be utilized by physicians to adequately educate patients with Paget's disease concerning potential complications following their primary TKA.

Body Mass Index and American Society of Anesthesiologists Score Predict Perioperative Delays in Different Phases for Total Hip Arthroplasty.

Perioperative efficiency has become increasingly important with cost constraints and expanding indications for total hip arthroplasty (THA). We chose to analyze body mass index (BMI) and American Society of Anesthesiologists (ASA) score, in predicting perioperative efficiency. We retrospectively reviewed the institutional database for primary THAs from July 2015 to January 2018. Patient demographics and perioperative times lines were collected. A multivariable model was utilized to evaluate BMI (< 30, ≥ 30) and ASA (< 3, ≥ 3) for all outcomes. A total of 2,934 patients were included with mean age 62.0 (12.2) years, and 1,599 (54.5%) were female. A BMI ≥ 30 was associated with prolonged operative time (p < 0.001) while an ASA ≥ 3 was predictive of post-anesthesia care unit time (p < 0.001), physical therapy hours (p < 0.001), and length of stay (p < 0.001). Both BMI (p = 0.004) and ASA (p < 0.001) were associated with skilled nursing/rehabilitation dispositions. While BMI predicts prolonged operative time, ASA predicts perioperative delays for anesthesia, nursing, and physical therapy. (Journal of Surgical Orthopaedic Advances 32(3):169-172, 2023).

Primary Total Knee Arthroplasty in Patients Aged 45 Years or Younger: 162 Total Knee Arthroplasties With a Mean Follow-up Duration of 7 Years.

Background: There are few large studies evaluating total knee arthroplasty (TKA) in young patients. Therefore, we sought to evaluate patients aged 45 years or younger undergoing a primary TKA. Methods: This was a retrospective, single-institution study, from 2003 to 2018, evaluating primary TKA in patients aged 45 years or younger. We identified 162 TKAs with a minimum follow-up duration of 2 years. Common surgical indications were degenerative joint disease (50%), post-traumatic arthritis (21%), and inflammatory arthritis (20%). Forty-nine knees had a prior significant knee surgery. We evaluated survivorship free of revision for any reason and aseptic revision. In addition, we characterized complication rates and risk factors for failure. Results: The mean age was 39 years, 70% were female, and the mean clinical follow-up duration was 7 years. At 8 years, survivorship free of revision for any reason was 82%, and survivorship free of aseptic revision was 87%. Fifty-five knees experienced at least 1 complication, with an overall complication rate of 34%. There were 6 (4%) periprosthetic joint infections (PJIs), and 24 (15%) knees of patients underwent manipulation under anesthesia with or without arthroscopic lysis of adhesions. There were no specific risk factors for revisions identified. Age less than 40 years was associated with PJI (P = .031), and marital status at the time of TKA was associated with arthrofibrosis requiring an intervention (P = .045). Conclusions: TKAs in patients aged 45 years or younger are associated with acceptable survivorship at a mean follow-up duration of 7 years. Patients should be counseled about the elevated risk of complications, specifically PJI and arthrofibrosis.

Erratum to 'Corynebacterium Total Hip and Knee Arthroplasy Prosthetic Joint Infections' [Arthroplasty Today 6 (2020) 163-168].

[This corrects the article DOI: 10.1016/j.artd.2020.03.008.].

Total Knee Arthroplasty in Patients with Dementia.

There are few studies evaluating total knee arthroplasty (TKA) in patients with dementia. The purpose of this study was to evaluate the rate of revision, complication, emergency department (ED) visitation, and discharge disposition in patients with dementia undergoing primary TKA. In this retrospective study, we evaluated patients from 2007 to 2017 using a national database. Ninety-day complications in patients with dementia undergoing TKA were increased risk of ED visitation and skilled nursing facility (SNF) disposition (p ≤ 0.05). Two-year complications in patients with dementia undergoing TKA were increased risk of ED visitation and SNF disposition (p ≤ 0.05). Patients with dementia undergoing TKA are at an increased risk of resource utilization.

Is primary total hip arthroplasty in patients with Down's syndrome associated with increased complications at 2 years follow-up?

INTRODUCTION: Previous reports on primary total hip arthroplasty (THA) in patients with Down's syndrome (DS) are often small and/or lack a comparison cohort, and thus it is challenging to draw meaningful conclusions about this group. The purpose of this study was to report on the post-operative complications in patients with DS undergoing primary THA, compared to a non-DS cohort. METHODS: In this retrospective study, we evaluated patients from 2010 to 2018 using a national database. We assessed surgical complications: closed reduction for dislocation, revision, resection, periprosthetic fracture, and infection in patients with a diagnosis of DS undergoing primary THA and compared them to a THA group of patients without DS. Patients undergoing THA for hip fractures were excluded. Complications were evaluated at 90 days and 2 years. Multivariable logistic regression analysis was used to adjust for age, sex, body mass index, and Charlson comorbidity index. RESULTS: At 90 days patients with DS had an increased risk of revision (OR 3.1, CI 1.14-8.41), but no significant risk of resection (OR 5.24, CI 0.73-37.8), closed reduction (OR 2.03, CI 0.28-14.59), infection (OR 1.48, CI 0.6-3.62), or periprosthetic fracture (OR 1.97, CI 0.27-14.14). At 2 years patients with DS had an increased risk of periprosthetic fracture (OR 5.88, CI 1.84-18.78), but no significant increased risk of revision (OR 1.82, CI 0.66-5.01), resection (OR 2.37, CI 0.33-17.17), or infection (OR 0.65, CI 0.2-2.07). CONCLUSIONS: Primary THA in patients with DS is associated with increased 90-day revision, and periprosthetic fracture at 2 years.

Is there a problem with modular dual mobility acetabular components in revision total hip arthroplasty at mid-term follow-up?

AIMS: Modular dual mobility (MDM) acetabular components are often used with the aim of reducing the risk of dislocation in revision total hip arthroplasty (THA). There is, however, little information in the literature about its use in this context. The aim of this study, therefore, was to evaluate the outcomes in a cohort of patients in whom MDM components were used at revision THA, with a mean follow-up of more than five years. METHODS: Using the database of a single academic centre, 126 revision THAs in 117 patients using a single design of an MDM acetabular component were retrospectively reviewed. A total of 94 revision THAs in 88 patients with a mean follow-up of 5.5 years were included in the study. Survivorship was analyzed with the endpoints of dislocation, reoperation for dislocation, acetabular revision for aseptic loosening, and acetabular revision for any reason. The secondary endpoints were surgical complications and the radiological outcome. RESULTS: The overall rate of dislocation was 11%, with a six-year survival of 91%. Reoperation for dislocation was performed in seven patients (7%), with a six-year survival of 94%. The dislocations were early (at a mean of 33 days) in six patients, and late (at a mean of 4.3 years) in four patients. There were three intraprosthetic dissociations. An outer head diameter of ≥ 48 mm was associated with a lower risk of dislocation (p = 0.013). Lumbrosacral fusion was associated with increased dislocation (p = 0.004). Four revision THAs (4%) were further revised for aseptic acetabular loosening, and severe bone loss (Paprosky III) at the time of the initial revision was significantly associated with further revision for aseptic acetabular loosening (p = 0.008). Fourteen acetabular components (15%) were re-revised for infection, and a pre-revision diagnosis of reimplantation after periprosthetic joint infection (PJI) was associated with subsequent PJI (p < 0.001). Two THAs had visible metallic changes on the backside of the cobalt chromium liner. CONCLUSION: When using this MDM component in revision THA, at a mean follow-up of 5.5 years, there was a higher rate of dislocation (11%) than previously reported. The size of the outer bearing was related to the risk of dislocation. There was a low rate of aseptic acetabular loosening. Longer follow-up of this MDM component and evaluation of other designs are warranted. Cite this article: Bone Joint J 2021;103-B(7 Supple B):66-72.

Antipsychotic Use Is Associated With Longer In-hospital Lengths of Stay and Higher Rates of Venous Thromboembolism and Costs of Care After Primary Total Knee Arthroplasty.

INTRODUCTION: Studies have shown that antipsychotic medication use may lead to venous thromboembolisms (VTEs); however, this association has not been demonstrated in patients undergoing primary total knee arthroplasty (TKA). Therefore, the purpose of this study was to investigate whether patients taking antipsychotic medications at the time of their primary TKA have higher rates of in-hospital lengths of stay (LOS), VTEs, and costs of care. METHODS: Patients taking antipsychotic medications were identified and matched to a cohort in a 1:5 ratio by age, sex, and medical comorbidities. Patients who had a history of VTEs or hypercoagulable states before their TKA were excluded. The query resulted in 439,579 patients within the study (n = 73,285) and matching cohorts (n = 366,294). Outcomes analyzed included rates of in-hospital LOS, VTEs, and costs of care. A P value less than 0.01 was considered statistically significant. RESULTS: We found statistically significant longer in-hospital LOS for patients taking antipsychotic medications (3.27 versus 3.02 days, P < 0.0001). Study patients were also found to have a higher incidence and odds ratio of VTEs (2.37 versus 1.04%; odds ratio: 1.86, 95% confidence interval: 1.75-1.97, P < 0.0001). Ninety-day costs of care were also significantly higher in the study cohort ($17,332.70 versus $15,975.00, P < 0.0001). CONCLUSION: After adjusting for confounders, patients taking antipsychotic medication were found to have higher rates of in-hospital LOS, VTEs, and costs of care. The study can be used by orthopaedic surgeons to counsel patients taking these medications concerning the potential complications after their procedure.

Mid-term results of tibial cones : reasonable survivorship but increased failure in those with significant bone loss and prior infection.

AIMS: Tibial cones are often utilized in revision total knee arthroplasty (TKA) with metaphyseal defects. Because there are few studies evaluating mid-term outcomes with a sufficient cohort, the purpose of this study was to evaluate tibial cone survival and complications in revision TKAs with tibial cones at minimum follow-up of five years. METHODS: A retrospective review was completed from September 2006 to March 2015, evaluating 67 revision TKAs (64 patients) that received one specific porous tibial cone during revision TKA. The final cohort was composed of 62 knees (59 patients) with five years of clinical follow-up or reoperation. The mean clinical follow-up of the TKAs with minimum five-year clinical follow-up was 7.6 years (5.0 to 13.3). Survivorship analysis was performed with the endpoints of tibial cone revision for aseptic loosening, tibial cone revision for any reason, and reoperation. We also evaluated periprosthetic joint infection (PJI), risk factors for failure, and performed a radiological review. RESULTS: The rate of cone revision for aseptic loosening was 6.5%, with an eight-year survival of 95%. Significant bone loss (Anderson Orthopaedic Research Institute grade 3) was associated with cone revision for aseptic loosening (p = 0.002). The rate of cone revision for any reason was 17.7%, with an eight-year survival of 84%. Sixteen percent of knees developed PJI following revision. A pre-revision diagnosis of reimplantation as part of a two-stage exchange protocol for infection was associated with both PJI (p < 0.001) and tibial cone revision (p = 0.001). CONCLUSION: Mid-term results of tibial cones showed a survivorship free of cone revision for aseptic loosening of 95%. Patients with significant bone loss were more likely to have re-revision for tibial cone failure. Infection was common, and patients receiving cones at reimplantation were more likely to develop PJI and undergo cone revision. Cite this article: Bone Joint J 2021;103-B(6 Supple A):158-164.

Cemented Femoral Fixation Using a Direct Anterior Approach: Background, Indications, and Surgical Technique.

The use of the direct anterior approach (DAA) in total hip arthroplasty has increased dramatically over the past decade. Potential benefits of the DAA include earlier functional recovery and lower risk of periprosthetic dislocation, but issues with periprosthetic fracture and femoral loosening have been reported, particularly in elderly patients. Cemented femoral fixation may offer a means to decrease early femoral failure in elderly patients undergoing the DAA. Here, we will present a step-by-step technique for cementing the femoral implant through the DAA.

Varus-Valgus Constrained Implants in Revision Total Knee Arthroplasty: Mean Clinical Follow-Up of Six Years.

BACKGROUND: There is scant literature evaluating varus-valgus constrained (VVC) prostheses in contemporary revision total knee arthroplasty (TKA). Therefore, we aimed to evaluate the durability of VVC revision TKA with selective use of cones. METHODS: A retrospective review of 194 revision TKAs with VVC was performed from August 2005 through February 2018 at a single institution. The final cohort consisted of 168 TKAs with a mean follow-up of 6 years. Stems were used in all but 1 TKA, tibial cones in 48%, and femoral cones in 19%. Anderson Orthopaedic Research Institute classification in femurs was 1 in 57, 2A in 33, 2B in 62, 3 in 16, and in tibias, 1 in 42, 2A in 29, 2B in 81, and 3 in 16. RESULTS: Survival analysis showed that 93% were free of revision for aseptic component loosening, 76% were free of revision for any reason, and 74% were free of reoperation at 6 years. Anderson Orthopaedic Research Institute 3 femur or tibia, age <65 years, and progressive radiographic changes were associated with an increased risk of revision for aseptic loosening (P < .05). Progressive radiographic changes were seen in 19% of femoral and 16% of tibial constructs. The most common reason for re-revision was periprosthetic joint infection (65%). CONCLUSION: VVC revision TKA with selective use of cones provided a reasonable outcome as 93% were free of revision for aseptic loosening at 6 years. However, given the rate of patients with progressive radiographic changes and survivorship free of reoperation of 74% at 6 years, long-term follow-up will help assess the durability of these constructs.

Are Patients Taking Benzodiazepines at Increased Risk for Complications Following Primary Total Knee Arthroplasty?

BACKGROUND: Benzodiazepines are commonly taken by patients who are undergoing total knee arthroplasty (TKA), but there is a paucity of studies evaluating any associations. Therefore, we hoped to study if patients taking preoperative benzodiazepines would have increased complications following TKA. METHODS: Using a nationwide database, from 2010 to 2019, we evaluated patients undergoing primary TKA who either did or did not have a preoperative record of benzodiazepine prescription. We performed a multivariable logistic regression analysis, adjusting for multiple variables (age, gender, obesity, and Charlson comorbidity index), to determine the association of preoperative benzodiazepine use and adverse events in a matched cohort. Furthermore, we stratified patients by one vs multiple preoperative benzodiazepine prescription(s). We evaluated 90-day and 2-year rates of revision, resection, femur fracture fixation, manipulation under anesthesia (MUA), and delirium. RESULTS: Patients filling more than one preoperative benzodiazepine prescription had increased adjusted odds of 90-day (odds ratio [OR] = 1.198, confidence interval [CI] = 1.086-1.320) and 2-year (OR = 1.188, CI = 1.125-1.254) revision; 90-day resection (OR = 1.430, CI = 1.125-1.817); 90-day (OR = 1.639, CI = 1.255-2.141) and 2-year (OR = 1.646, CI = 1.412-1.919) femur fracture fixation; and 2-year delirium (OR = 2.288, CI = 1.564-3.382). Preoperative benzodiazepine users had decreased adjusted odds of 90-day (OR = 0.670, CI = 0.639-0.702) and 2-year (OR = 0.702, CI = 0.671-0.734) MUA. CONCLUSION: After controlling for multiple variables, benzodiazepine use was associated with increased rates of revision, resection, femur fracture fixation, and delirium. Furthermore, benzodiazepine use was also associated with a decreased rate of MUA. Orthopaedic professionals can counsel patients taking this group of medications about the associated adverse events. Future studies should assess the use of other muscle relaxants in the prevention of knee stiffness and MUA.

Angiotensin Receptor Blockers Were Not Associated With Decreased Arthrofibrosis After Total Knee Arthroplasty.

Stiffness after total knee arthroplasty (TKA) remains a challenging problem. Angiotensin receptor blockers (ARBs) have been associated with decreased muscle fibrosis. The aim of this study was to evaluate whether perioperative use of ARBs was associated with a reduction in arthrofibrosis and manipulation under anesthesia (MUA) in patients undergoing primary TKA at 90 days and 1 year postoperative. In this retrospective study, the authors used a national database to evaluate patients undergoing TKA for primary osteoarthritis from 2007 to 2017. They evaluated patients with filled prescriptions for ARBs within the study time frame and the specific type of ARB and its association with arthrofibrosis and MUA. After adjusting for age, sex, a comorbidity index, and obesity, any ARB or specific ARBs were not associated with a reduction in the rate of arthrofibrosis or MUA after TKA (P≥.05). Male sex, age 55 years or older, and obesity were associated with a reduction in the rate of arthrofibrosis and MUA after TKA (P≤.05). Studies should be performed to evaluate ARBs to see whether there is a more specific role in preventing joint stiffness in certain patient subpopulations following TKA. [Orthopedics. 2021;44(2):e274-e280.].

Paget's Disease in Primary Total Hip Arthroplasty Is Associated With Greater In-Hospital Lengths of Stay, Costs, and Complications.

BACKGROUND: There are few well-powered studies investigating the association of Paget's disease of bone on patients undergoing primary total hip arthroplasty (THA). This study utilized a nationwide database to determine whether Paget's patients undergoing primary THA are associated with higher rates of (1) lengths of stay (LOS); (2) costs; and (3) complications (medical/surgical and implant-related). METHODS: Using International Classification of Diseases, Ninth Revision and Current Procedural Terminology codes, Paget's patients undergoing primary THA were identified and matched to non-Paget's patients in a 1:5 ratio by age, sex, and comorbidities utilizing the PearlDiver database. This resulted in 21,714 patients in Paget's (n = 3619) and non-Paget's (n = 18,095) cohorts. Outcomes assessed included LOS, episode-of-care costs, medical/surgical complications, and implant-related complications. A P value less than .003 was considered statistically significant. RESULTS: Compared to the matched cohort, Paget's patients undergoing primary THA had significantly longer LOS (P < .0001), higher 90-day total global episode-of-care costs (P < .0001), higher 90-day medical and surgical complications (P < .0001), and higher implant-related complications (P < .0001). CONCLUSION: We found that Paget's was associated with higher rates of LOS, costs, and complications. Although there was an association found, the risk appears reasonably low compared to the matched cohort. The study can be utilized by orthopedic professionals to counsel and educate these patients of potential complications which may occur following their procedure.

1.5-Stage Exchange Arthroplasty for Total Knee Arthroplasty Periprosthetic Joint Infections.

BACKGROUND: Periprosthetic joint infection (PJI) in total knee arthroplasty (TKA) is a challenging problem. The purpose of this study was to outline a novel technique to treat TKA PJI. We define 1.5-stage exchange arthroplasty as placing an articulating spacer with the intent to last for a prolonged time. METHODS: A retrospective review was performed from 2007 to 2019 to evaluate patients treated with 1.5-stage exchange arthroplasty for TKA PJI. Inclusion criteria included: articulating knee spacer(s) remaining in situ for 12 months and the patient deferring a second-stage reimplantation because the patient had acceptable function with the spacer (28 knees) or not being a surgical candidate (three knees). Thirty-one knees were included with a mean age of 63 years, mean BMI 34.4 kg/m2, 12 were female, with a mean clinical follow-up of 2.7 years. Cobalt-chrome femoral and polyethylene tibial components were used. We evaluated progression to second-stage reimplantation, reinfection, and radiographic outcomes. RESULTS: At a mean follow-up of 2.7 years, 25 initial spacers were in situ (81%). Five knees retained their spacer(s) for some time (mean 1.5 years) and then underwent a second-stage reimplantation; one of the five had progressive radiolucent lines but no evidence of component migration. Three knees (10%) had PJI reoccurrence. Four had progressive radiolucent lines, but there was no evidence of component migration in any knees. CONCLUSIONS: 1.5-stage exchange arthroplasty may be a reasonable method to treat TKA PJI. At a mean follow-up of 2.7 years, there was an acceptable rate of infection recurrence and implant durability.

A Specific Capsular Repair Technique Lowered Early Dislocations in Primary Total Hip Arthroplasty Through a Posterior Approach.

BACKGROUND: Dislocation is a challenging problem after total hip arthroplasty (THA). We sought to evaluate the incidence of early dislocation with 2 different posterior repair techniques after THA using a posterior approach. METHODS: From September of 2008 to August of 2019, we evaluated 841 THAs performed by a single surgeon using a posterior approach. Before November of 2015, the capsule was repaired to the greater trochanter (group 1, 605 patients). Starting November 2015, the posterior capsule was repaired in a side-to-side fashion (direct soft-tissue repair) (group 2, 236 patients). There was a mean follow-up of 31.1 months (range, 2.5-122.5 months). A multivariable logistic regression model was constructed to assess the impact of baseline patient and operative factors on the dislocation rate. RESULTS: There were 22 dislocations, all of which occurred in group 1. There were no dislocations in group 2. After adjusting for patient and operative factors, the direct soft-tissue repair had a large impact on the overall multivariable model as indicated by its effect likelihood ratio of 10.33 (P = .001); however, the odds ratio was not calculable for this factor, given that there were no dislocations in hips with direct soft-tissue repair. Increasing age was associated with an increased odds of dislocation (odds ratio, 1.04, P = .017), with an effect likelihood ratio of 6.25 (P = .012). CONCLUSIONS: Switching from a capsular repair to the greater trochanter to a side-to-side capsular repair was associated with a decreased rate of dislocation in primary THA through a posterior approach.

Corynebacterium Total Hip and Knee Arthroplasy Prosthetic Joint Infections.

Prosthetic joint infections (PJIs) are typically caused by Staphylococcus aureus and coagulase-negative Staphylococci species. Corynebacterium species are microorganisms of the human skin and mucous membranes that are often considered contaminants when grown in culture. In the past, Corynebacterium species were often classified as diphtheroids based on growing as gram-positive rods in aerobic environments, but with advances in technology, the identification of Corynebacterium species has improved. Corynebacterium can cause infection, but there are few case reports of orthopaedic infection. We present 3 cases of total hip arthroplasty and 3 cases of total knee arthroplasty PJI caused by Corynebacterium species. We found a high failure rate of surgical treatment of Corynebacterium PJI, defined as reoperation for infection. This information adds to the limited literature on these organisms in total joint arthroplasty PJI.