Point-of-Care Coating of Revision Femoral Stems With Antibiotic-Loaded Calcium Sulfate: Reduction in Infection After 2nd Stage Reimplantation but Not With Aseptic Revisions.

Background: Infection rates in revision total hip arthroplasty are lower when antibiotic loaded cemented stems are utilized. Inspired by this technique, a point-of-care coating of antibiotic-loaded calcium sulfate (CaSO4) was applied to cementless revision stems in aseptic revision and 2nd stage reimplantation total hip arthroplasty. Methods: One hundred eleven consecutive femoral stems were coated. Just prior to insertion, 10 cc of CaSO4 was mixed with 1 g vancomycin and 240 mg tobramycin with the paste applied to the stem. The results were compared to a matched cohort (N = 104) performed across the previous 5 years. The surgical methods were comparable, but for the stem coating. The study group was followed for a minimum of 3 years. Results: In the study cohort of 111 patients, there were 69 aseptic revisions with one periprosthetic joint infection (PJI) (1.4%) and 42 second-stage reimplantations with 2 PJIs (4.8%). In the control cohort of 104 patients, there were 74 aseptic revisions with one PJI (1.4%) and 30 second-stage reimplantations with 7 PJIs (23.3%). There was no significant reduction in PJI rate in the aseptic revision subgroup (1.4% study vs 1.4% control group), P = 1.000. Antibiotic stem coating reduced PJI rate in the 2nd stage reimplantation subgroup (23.3% control vs 4.8% study group), P = .028. In both groups, there were no cases of aseptic stem loosening. Conclusions: Point-of-care antibiotic coating of cementless revision femoral stems reduces PJI infection rate in 2nd stage reimplantations only. We theorize that microbes persist in the endosteal cortices after resection and may contribute to infection recurrence.

Prosthetic Limb Attachment via Electromagnetic Attraction through a Closed Skin Envelope.

OBJECTIVE: Current socket-based methods of prosthetic limb attachment are responsible for many of the dominant problems reported by persons with amputation. In this work, we introduce a new paradigm for attachment via electromagnetic attraction between a bone-anchored ferromagnetic implant and an external electromagnet. Our objective was to develop a design framework for electromagnetic attachment, and to evaluate this framework in the context of transfemoral amputation. METHODS: We first used inverse dynamics to calculate the forces required to suspend a knee-ankle-foot prosthesis during gait. We then conducted cadaveric dissections to inform implant geometry and design a surgical methodology for covering the implant. We also developed an in silico framework to investigate how electromagnet design affects system performance. Simulations were validated against benchtop testing of a custom-built electromagnet. RESULTS: The physical electromagnet matched simulations, with a root-mean-square percentage error of 4.2% between measured and predicted forces. Using this electromagnet, we estimate that suspension of a prosthesis during gait would require 33 W of average power. After 200 and 1000 steps of simulated walking, the temperature at the skin would increase 2.3℃ and 15.4℃ relative to ambient, respectively. CONCLUSION: Our design framework produced an implant and electromagnet that could feasibly suspend a knee-ankle-foot prosthesis during short walking bouts. Future work will focus on optimization of this system to reduce heating during longer bouts. SIGNIFICANCE: This work demonstrates the initial feasibility of an electromagnetic prosthetic attachment paradigm that has the potential to increase comfort and improve residual limb health for persons with amputation.

MELD score predicts short-term outcomes after surgical management of proximal humerus fractures: a matched analysis.

Objective: We aimed to evaluate the difference in 30-day outcomes after surgical management of proximal humerus fractures (PHFs) between patients with and without chronic liver disease as defined by a MELD score greater than 10. Design: This was a retrospective database review. Setting: All centers participating in the American College of Surgeons National Surgical Quality Improvement Program database were included. Patients/Participants: Patients with proximal humerus fractures who (1) underwent ORIF, HA, or SA and (2) had calculable MELD scores were included. Intervention: Open reduction and internal fixation, hemiarthroplasty, or shoulder arthroplasty was used for treatment. Main outcome measurements: Thirty-day complications, mortality, readmission, and reoperation rates were measured. Results: Of the total 1732 PHF patients identified, 300 had a MELD score higher than 10. After propensity matching by significant covariates, MELD score higher than 10 was found to be significantly associated with higher rates of 30-day mortality, 30-day readmission, transfusion within 72 hours, and systemic complications. Among patients with a MELD score higher than 10, treatment with SA or HA instead of ORIF was associated with a higher rate of transfusion and longer operative time. There were no significant differences between treatment cohorts regarding mortality, reoperation, readmission, or complications. Conclusions: A MELD score higher than 10 is associated with higher risk of surgical complications, transfusion, and death in patients undergoing surgery for proximal humerus fractures. Among patients with a MELD score higher than 10, ORIF was associated with a lower transfusion rate and shorter operative time than arthroplasty or hemiarthroplasty. Level of Evidence: Prognostic Level III.

Monoclonal Antibody Disrupts Biofilm Structure and Restores Antibiotic Susceptibility in an Orthopedic Implant Infection Model.

Bacterial biofilms on orthopedic implants are resistant to the host immune response and to traditional systemic antibiotics. Novel therapies are needed to improve patient outcomes. TRL1068 is a human monoclonal antibody (mAb) against a biofilm anchoring protein. For assessment of this agent in an orthopedic implant infection model, efficacy was measured by reduction in bacterial burden of Staphylococcus aureus, the most common pathogen for prosthetic joint infections (PJI). Systemic treatment with the biofilm disrupting mAb TRL1068 in conjunction with vancomycin eradicated S. aureus from steel pins implanted in the spine for 26 of 27 mice, significantly more than for vancomycin alone. The mechanism of action was elucidated by two microscopy studies. First, TRL1068 was localized to biofilm using a fluorescent antibody tag. Second, a qualitative effect on biofilm structure was observed using scanning electron microscopy (SEM) to examine steel pins that had been treated in vivo. SEM images of implants retrieved from control mice showed abundant three-dimensional biofilms, whereas those from mice treated with TRL1068 did not. Clinical Significance: TRL1068 binds at high affinity to S. aureus biofilms, thereby disrupting the three-dimensional structure and significantly reducing implant CFUs in a well-characterized orthopedic model for which prior tested agents have shown only partial efficacy. TRL1068 represents a promising systemic treatment for orthopedic implant infection.

Renal Transplant Patients Have a Lower Risk of Complications and Mortalities After Total Knee Arthroplasty Compared to Those on Hemodialysis: A Large National Database Study.

BACKGROUND: Total knee arthroplasty (TKA) in end-stage renal disease is associated with complications. Controversy exists whether elective TKA should be performed while patients are on hemodialysis (HD) or following renal transplant (RT). This study compares TKA outcomes in HD versus RT patients. METHODS: A national database was retrospectively reviewed using International Classification of Diseases codes to identify HD and RT patients who underwent primary TKA from 2010 to 2018. Demographics, comorbidities, and hospital factors were compared using Wald and Chi-squared tests. The primary outcome was in-hospital mortalities while secondary outcomes included quality outcomes and medical/surgical complications. Multivariate regressions were used to determine independent associations. Significance was determined with a 2-tailed P value of .05. There were 13,611 patients who underwent TKA (61.1 HD and 38.9% RT). Patients who had RT were younger, had fewer comorbidities, and more likely to have private insurance. RESULTS: The RT patients had a lower rate of mortality (odds ratio (OR) 0.23, P < .01)), complications (OR 0.63, P < .01), cardiopulmonary complications (OR 0.44, P = .02), sepsis (OR 0.22, P < .001), and blood transfusion (OR 0.35, P < .001) during the index hospitalization. This cohort was also found to have decreased length of stay (-2.0 days, P < .001), non-home discharge (OR 0.57, P < .001), and hospital cost (-$5,300, P < .001). Patients who had RT had a lower rate of readmission (OR 0.54, P < .001), periprosthetic joint infection (OR 0.50, P < .01), and surgical site infection (OR 0.37, P < .001) within 90 days. CONCLUSION: These findings suggest that HD patients are a high-risk population in TKA compared to RT patients and warrant stringent perioperative monitoring.

Geriatric Distal Femur Fractures: Equivalent Long-Term Reoperation Rates Between Fixation and Primary Arthroplasty.

OBJECTIVE: Our primary objectives were to (1) determine the rate of requiring conversion to arthroplasty after open reduction internal fixation (ORIF) of geriatric distal femur fractures and (2) compare 10-year reoperation rates after ORIF versus primary arthroplasty for geriatric distal femur fractures. DESIGN: Propensity-matched retrospective cohort study. SETTING: All centers participating in the California Office of Statewide Health Planning and Development (OSHPD) database. PATIENTS/PARTICIPANTS: All patients 65 years of age or older who underwent operative management of a distal femur fracture between 2000 and 2017. INTERVENTION: ORIF, total knee arthroplasty (TKA), or distal femur replacement (DFR). MAIN OUTCOME MEASUREMENTS: Reoperation. RESULTS: A total of 16,784 patients with geriatric distal femur fracture were identified, of which 16,343 (97.4%) underwent ORIF. The cumulative incidence of conversion to arthroplasty within 10 years of ORIF was found to be 3.5%, with young age and female sex identified as risk factors for conversion. There was no significant difference in 10-year reoperation-free survival rate between propensity-matched patients undergoing ORIF versus primary arthroplasty (94.5% vs. 96.2%, P = 0.659). There were no differences in short-term complication or readmission rates between matched treatment cohorts, but arthroplasty was associated with a higher rate of wound infection within 90 days (2.0% vs. 0.2%, P = 0.011). CONCLUSIONS: The 10-year cumulative incidence of conversion to arthroplasty after ORIF was found to be low. There was no significant difference in long-term reoperation-free survival rates between patients undergoing ORIF versus primary arthroplasty. Primary arthroplasty was associated with significantly higher rates of acute wound or joint infection. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Comparison of complication profiles for femoral neck, intertrochanteric, and subtrochanteric geriatric hip fractures.

INTRODUCTION: Most geriatric hip fractures occur in the femoral neck (FN) and intertrochanteric (IT) regions of the femur, while a minority occur in the subtrochanteric (ST) region. Relative outcomes based on the anatomical subtype of fracture are not well studied. This study characterizes postoperative complications and outcomes of hip fractures distinguished by anatomic region. MATERIALS AND METHODS: The targeted hip fracture series of the American College of Surgeons National Surgical Quality Improvement Program database was queried to identify geriatric (≥ 65 years) patients who sustained operative FN, IT, and ST hip fractures. Primary patient demographic and perioperative data were collected and correlated with 30-day postoperative complications and outcomes. Multivariate regression was used to calculate relative risks of adverse events (AEs) between groups. RESULTS: In total, 8220 geriatric hip fracture patients were identified. Risk-adjusted 30-day mortality was not significantly different between patients with ST (5.8%, p = 0.735) and IT (7.3%, p = 0.169) femur fractures relative to those with FN fractures (6.6%). The overall risk-adjusted rate of minor and major medical AEs within 30 days and risk-adjusted rate of wound complications was not significantly different between FN, IT, and ST fractures. Patients with IT [34.4%, OR 2.35 (2.35-3.08), p < 0.001] and ST fractures [49.8%, OR 5.94 (4.58-7.70), p < 0.00] had higher risk-adjusted incidence of postoperative blood transfusion relative to FN fractures (18.5%). Furthermore, patients with IT fractures had a slightly lower risk-adjusted incidence of unplanned reoperation [2.1 vs. 2.7%, OR 0.69 (0.47-0.99), p = 0.046] and hospital readmission (7.8 vs. 9.2%, OR 0.76 [0.63-0.91], p = 0.003) than patients with FN fractures. CONCLUSIONS: With respect to anatomic region, geriatric hip fractures have similar short-term mortality and medical AE profiles with differences in transfusion, reoperation, and readmission rates. Knowledge of these short-term outcomes may guide surgeons in counseling hip fracture patients peri-operatively.

Comparison of total hip arthroplasty outcomes between haemodyalisis and renal transplant patients.

INTRODUCTION: Total hip arthroplasty (THA) in end-stage renal disease (ESRD) patients is associated with increased complications. Controversy exists whether elective THA should be performed while these patients are on haemodialysis (HD) or following renal transplant (RT). This study seeks to compare THA outcomes in HD versus RT patients. METHODS: A national database was retrospectively reviewed using ICD codes to identify all HD and RT patients who underwent primary THA from 2010 to 2018. Demographics, comorbidities, and hospital factors were compared between cohorts using Wald and chi-square tests. The primary outcome was in-hospital mortality, while secondary outcomes included length of stay (LOS), non-home discharge, cost, readmission, and medical/surgical complications. Multivariate regression was used to determine independent associations. Significance was determined with a 2-tailed p-value of 0.05. RESULTS: 11,133 patients underwent THA, 61.6% HD and 39.4% RT patients. RT patients were younger, had fewer comorbidities, and more likely to have private insurance. After adjusting for these differences, RT patients had a lower rate of mortality (OR 0.31, p = 0.01), complications (OR 0.54, p < 0.01), cardiopulmonary complications (OR 0.54, p = 0.04), sepsis (OR 0.43, p < 0.01), and blood transfusion (OR 0.39, p < 0.001) during the index hospitalisation. RT was associated with decreased LOS (-2.0 days, p < 0.001), non-home discharge (OR 0.35, p < 0.001), and hospital cost (-$6,000, p < 0.001). RT had a lower rate of readmission (OR 0.60, p < 0.001) and revision surgery (OR 0.24, p = 0.01) within 90 days. CONCLUSIONS: These findings suggest HD patients are a high-risk population in THA compared to RT patients and warrant stringent perioperative monitoring.

Biphasic bone graft substitute in revision total hip arthroplasty with significant acetabular bone defects : a retrospective analysis.

AIMS: Large acetabular bone defects encountered in revision total hip arthroplasty (THA) are challenging to restore. Metal constructs for structural support are combined with bone graft materials for restoration. Autograft is restricted due to limited volume, and allogenic grafts have downsides including cost, availability, and operative processing. Bone graft substitutes (BGS) are an attractive alternative if they can demonstrate positive remodelling. One potential product is a biphasic injectable mixture (Cerament) that combines a fast-resorbing material (calcium sulphate) with the highly osteoconductive material hydroxyapatite. This study reviews the application of this biomaterial in large acetabular defects. METHODS: We performed a retrospective review at a single institution of patients undergoing revision THA by a single surgeon. We identified 49 consecutive patients with large acetabular defects where the biphasic BGS was applied, with no other products added to the BGS. After placement of metallic acetabular implants, the BGS was injected into the remaining bone defects surrounding the new implants. Patients were followed and monitored for functional outcome scores, implant fixation, radiological graft site remodelling, and revision failures. RESULTS: Mean follow-up was 39.5 months (36 to 71), with a significant improvement in post-revision function compared to preoperative function. Graft site remodelling was rated radiologically as moderate in 31 hips (63%) and strong in 12 hips (24%). There were no cases of complete graft site dissolution. No acetabular loosening was identified. None of the patients developed clinically significant heterotopic ossification. There were twelve reoperations: six patients developed post-revision infections, three experienced dislocations, two sustained periprosthetic femur fractures, and one subject had femoral component aseptic loosening. CONCLUSION: Our series reports bone defect restoration with the sole use of a biphasic injectable BGS in the periacetabular region. We did not observe significant graft dissolution. We emphasize that successful graft site remodelling requires meticulous recipient site preparation.Cite this article: Bone Jt Open 2022;3(12):991-997.

Platelet-rich plasma use for hip and knee osteoarthritis in the United States.

BACKGROUND: Hip and knee osteoarthritis (OA) are rising in prevalence and increasingly affecting younger patients. There is a rising demand for therapeutics to address its growing disease burden. Platelet-rich plasma (PRP) therapy has been used to treat various musculoskeletal conditions, but its role in OA treatment is not well understood. Even still, there is significant interest in this biologic for treatment of OA. The purpose of this study was to determine the PRP utilization trends in the United States for hip and knee OA. METHODS: This was a retrospective review from the PearlDiver Patient Record Database. International Classification of Diseases and Current Procedural Terminology codes were used to identify patients who had received PRP injections for hip and knee OA from 2010 to 2018. Injection incidence was evaluated on an annual basis and by patient demographics, geographic distribution, and medical specialty under which the treatment was administered. RESULTS: A total of 3,884 PRP injections were administered over the study period, 15% for hip OA and 85% for knee OA. PRP injections per 100,000 patient cases increased by an average year-over-year percentage of 53% and 12% for hip and knee OA, respectively. The highest injection incidences were observed in patients younger than 44 years of age. 58% of both hip and knee PRP injections were administered in general orthopaedic practices. CONCLUSION: These findings show that PRP is increasingly being used as a treatment modality for hip and knee OA. There is a need for further research on its long term outcomes.

Renal disease is a risk factor for complications and mortality after open reduction internal fixation of proximal humerus fractures.

Background: Renal osteodystrophy predisposes renal disease patients to fracture. Proximal humerus fractures (PHFs) frequently undergo open reduction internal fixation (ORIF); however, the effect of renal disease on outcomes is unknown. Methods: A retrospective review of the Nationwide Readmissions Database used International Classification of Diseases, 9th Revision, codes to identify patients who underwent ORIF for closed PHF from 2010 to 2014 with no renal disease, predialysis chronic renal disease (CRD), and end-stage renal disease (ESRD). Results: A total of 85,433 patients were identified, including 5498 (6.4%) CRD and 636 (0.7%) ESRD. CRD and ESRD patients had increased age, comorbidities, and rates of Medicare insurance. After adjusting for differences, CRD and ESRD patients were at increased risk of any complication (odds ratio [OR] 2.48, 1.66), blood transfusion (OR 1.85, 3.31), respiratory complications (OR 1.14, 1.59), acute renal failure (OR 4.80, 1.67), systemic infection (OR 2.00, 3.14), surgical site infection (OR 1.52, 3.87), longer length of stay (7.1 and 12.9 days vs. 5.9 days), and higher cost ($21,669 and $35,413 vs. $20,394) during index hospitalization, as well as surgical site infection (OR 1.43, 3.03) and readmission (OR 1.61, 3.69) within 90 days of discharge, respectively, compared with no renal disease patients. During index hospitalization, CRD patients also had increased risk for periprosthetic fracture (OR 4.97) and cardiac complications (OR 1.47), whereas ESRD patients had increased risk of mortality (OR 5.79), wound complication (2.67), and deep vein thrombosis (OR 16.70). Conclusion: These findings suggest renal patients are at increased risk for complications after PHF ORIF, highlighting the importance of close perioperative monitoring and appropriate patient selection in this population, including strong consideration of nonoperative management.

Subsidence of monoblock and modular titanium fluted tapered stems in revision hip arthroplasty: A retrospective multicentre comparison study.

Background: Tapered, fluted, titanium (TFT) stems have shown good clinical outcomes in revision total hip arthroplasty (rTHA), however concerns exist regarding early subsidence. This study compares subsidence between a modern monoblock 3-degree and a modular 2-degree TFT stem in rTHA. Methods: A retrospective, international multicentre comparative study was conducted including 64 rTHA in 63 patients. A monoblock TFT stem was used in 37 cases and a modular TFT stem was used in 27 cases. Patient demographics, Paprosky femoral bone loss classification, bicortical contact and stem subsidence were recorded at minimum four week follow up. Results: There was no statistically significant difference in overall subsidence (p = 0.318) or the rate of subsidence >10 mm between stems. Mean subsidence was 2.13 mm in the monoblock group and 3.15 mm in the modular group. Two stems subsided >10 mm: one in each group. There was no difference in bicortical contact between groups (p = 0.98). No re-revisions were performed. Conclusions: We found no difference in subsidence between the two stems. Surgeons may consider the use of monoblock stems in rTHA as they have comparably low rates of subsidence and eliminate the small but potentially catastrophic risk of implant fracture at modular junctions associated with modular stems.

Strategies for Pertrochanteric Fracture Reduction and Intramedullary Nail Placement: Technical Tips and Tricks.

The incidence of pertrochanteric hip fractures continues to rise as the aging population expands. Despite advancements in techniques and implants, failure rates remain up to 16% in the literature. The recognition of challenging fracture patterns and the use of meticulous preoperative planning can help to avoid common pitfalls. Understanding fluoroscopic views for reduction assessment and implant placement is instrumental in preventing fixation failure. In addition, adjunctive techniques including the use of a bone hook, cerclage wire, and colinear clamps can facilitate reduction efforts. It is imperative for the surgeon to recognize common pitfalls and to consider a wide array of techniques to manage these challenging and common fractures.

Epidemiology of Revision Total Knee Arthroplasty in the United States, 2012 to 2019.

Background: As primary total knee arthroplasty volume continues to increase, so will the number of revision total knee arthroplasty (rTKA) procedures. The purpose of this study is to provide an updated perspective on the incidence, indications, and financial burden of rTKA in the United States. Material and methods: This was a retrospective epidemiologic analysis using the National Inpatient Sample. International Classification of Diseases ninth and tenth revision codes were used to identify patients who underwent rTKA and create cohorts based on rTKA indications from 2012 to 2019. National and regional trends for length of stay, cost, and discharge location were evaluated. Results: A total of 505,160 rTKA procedures were identified. The annual number of rTKA procedures increased by 29.6% over the study period (56,490 to 73,205). The top 3 indications for rTKA were aseptic loosening (23.1%), periprosthetic joint infection (PJI) (20.4%), and instability (11.0%). Over the study period, the proportion of patients discharged to skilled nursing facility decreased from 31.7% to 24.1% (P < .001). Hospital length of stay decreased from 4.0 days in 2012 to 3.8 days in 2019 (P < .001). Hospital costs increased by $1300 from $25,730 to $27,077 (P < .001). The proportion of rTKA cases performed at urban academic centers increased (52.1% to 74.3%, P < .001) while that at urban nonacademic centers decreased (39.0% to 19.2%, P < .001). Conclusion: The top 3 indications for rTKA were aseptic loosening, PJI, and instability, with PJI becoming the most common indication in 2019. These cases are increasingly being performed at urban academic centers and away from urban nonacademic centers. Level of Evidence: 3 (Retrospective cohort study).

Navigated and Robot-Assisted Technology in Total Knee Arthroplasty: Do Outcome Differences Achieve Minimal Clinically Important Difference?

BACKGROUND: In total knee arthroplasty (TKA), computer-assisted navigation (N-TKA) and robotic-assisted methods (RA-TKA) are intended to increase precision of mechanical and component alignment. However, the clinical significance of published patient-reported outcome measure (PROM) differences in comparison to conventional TKA (C-TKA) is unknown. METHODS: A systematic review was performed to identify all studies reporting perioperative PROMs for either primary N-TKA or RA-TKA with a C-TKA comparison cohort with a minimum 1-year follow-up. Relative improvements in PROMs for the two cohorts were compared to published minimal clinically important difference (MCID) values. RESULTS: After systematic review, 21 studies (N = 3,214) reporting on N-TKA and eight studies (N = 1,529) reporting on RA-TKA met inclusion criteria. Eighteen of 20 studies (90%) reported improved radiographic outcomes with N-TKA relative to C-TKA; five of five studies reported improved radiographic outcomes with RA-TKA relative to C-TKA. Five of 21 studies (24%) reported statistically significant greater improvements in clinical PROMs for N-TKA relative to C-TKA, whereas only two (10%) achieved clinical significance relative to MCID on a secondary analysis. One of 8 studies (13%) reported statistically significant greater improvements in PROMs for RA-TKA relative to C-TKA, whereas none achieved clinical significance relative to MCID on a secondary analysis. No studies reported a significant difference in revision rates. CONCLUSION: While most studies comparing RA-TKA and N-TKA with C-TKA demonstrate improved radiographic alignment outcomes, a minority of studies reported PROM differences that achieve clinical significance. Future studies should report data and be interpreted in the context of clinical significance to establish patient and surgeon expectations for emerging technologies.

Comparison of Total Knee Arthroplasty Outcomes Between Renal Transplant and End Stage Renal Disease Patients.

INTRODUCTION: Patients with end-stage renal disease (ESRD) have increased risk for periprosthetic joint infection (PJI) due to their predisposition for bacteremia and subsequent implant inoculation secondary to dialysis. PJI risk is also elevated in transplant patients secondary to chronic immunosuppressive therapy. The purpose of this study was to compare medical and surgical complications after primary total knee arthroplasty (TKA) in patients with ESRD or renal transplant (RT). METHODS: This was a retrospective review from the PearlDiver database. International Classification of Diseases and Current Procedural Terminology codes were used to identify patients with ESRD or RT who underwent primary TKA for osteoarthritis from 2015 to 2019. Univariate and multivariable logistic regression analyses were done for medical complications up to 90 days and surgical complications up to 2 years. RESULTS: Within 90 days of TKA, patients with RT were less likely to develop pneumonia (odds ratio [OR] 0.46, 95% confidence interval [CI] 0.23 to 0.84, P = 0.018) and wound dehiscence (OR 0.46, 95% CI 0.21 to 0.90, P = 0.015). Patients with RT had a lower risk for PJI at 1 year (OR 0.61, 95% CI 0.36 to 0.99, P = 0.017) and at 2 years (OR 0.56, 95% CI 0.34 to 0.88, P = 0.017) after primary TKA. DISCUSSION: Consideration should be given to delaying TKA in patients with ESRD who are RT candidates.

Revision Total Hip Arthroplasty in Solid Organ Transplant Patients: A Propensity Score-Matched Cohort Study for Aseptic and Infected Revisions.

BACKGROUND: Previous studies have demonstrated that solid organ transplant (SOT) patients undergoing primary total hip arthroplasty (THA) are at an increased risk of postoperative complications. The purpose of this study is to use a large, national database to investigate revision THA (rTHA) outcomes in SOT patients. METHODS: Nationwide Readmissions Database (NRD) from 2010-2018 was used, and ICD-9 and ICD-10 codes were used to identify all patients who underwent rTHA, including those with history of SOT. Propensity score matching (PSM) was used to analyze rTHA outcomes in SOT patients comparted to matched controls. Separate analysis performed for patients undergoing rTHA for prosthetic joint infection (PJI) vs other causes. RESULTS: A total of 414,756 rTHA, with 1837 of those being performed in SOT patients, were identified. Of these, 65,961 and 276 were performed for PJI in non-SOT and SOT patients, respectively. For non-PJI patients, SOT patients had higher 90-day all-cause readmission rates (24.0% vs 19.4%, P = .03) but lower rate for readmission related to rTHA (6.0% vs 9.2%, P = .03), but no difference readmission for specific rTHA complications, mortality (0.6% vs 1.3%, P = .20), or revision rTHA. Of PJI patients, SOT patients had no difference in overall 90-day readmission (38.6 vs 31.3%, P = .280), readmission for specific rTHA complications, re-revision, or mortality (4.7% vs 6.0%, P = .63). CONCLUSIONS: SOT patients undergoing rTHA for aseptic reasons are higher risk of overall readmission but lower risk of readmission related to rTHA than appropriately matched controls. SOT PJI patients undergoing had similar rates of readmission, mortality, and revision surgery compared to matched non-SOT PJI patients.

Outcomes of Modular Knee Arthrodesis for Challenging Periprosthetic Joint Infections.

BACKGROUND: Modular knee arthrodesis (MKA) is a salvage treatment option for patients with challenging periprosthetic joint infections (PJI). The purpose of this study was to investigate the outcomes of patients who underwent MKA for PJI with a single technique and determine if specific factors are associated with MKA failure. METHODS: This was a retrospective review of 81 patients who underwent MKA at a single institution. Knee Society Scores were recorded before MKA and at the final follow-up (mean 52 months). Poisson regression was used to calculate rate ratios for MKA failure secondary to infection. RESULTS: The mean patient age was 67 years; most patients were McPherson B hosts (56.8%) and had type 3 extremities (53.1%), and all had a type III infection (chronic, >4 wks). Forty-six percent of patients had a prior explantation (59.5% failed 2-stage, 40.5% failed spacer). Staphylococcus epidermidis and Staphylococcus aureus were the most common organisms, 22.2% and 18.5%, respectively. Thirty percent of patients had at least one reoperation, excluding reimplantation (14.8% irrigation and debridement/wound closure, 9.9% MKA exchange, and 7.4% amputation). Of 82.7% of MKA patients with no evidence of infection, 82.1% (56 patients) underwent reimplantation endoprosthetic reconstruction, and 67.3% of these remained infection-free at the final follow-up. DISCUSSION: MKA is a salvage option for challenging PJI cases that may serve as definitive surgical management or as a bridge to endoprosthetic reconstruction for patients who have failed prior infection control procedures.

Revision total knee arthroplasty outcomes in solid organ transplant Patients, a matched cohort study of aseptic and infected revisions.

BACKGROUND: Previous studies have demonstrated that solid organ transplant (SOT) patients undergoing primary total knee arthroplasty (TKA) are at an increased risk of postoperative complications. The purpose of this study is to utilize a large, national database to investigate revision TKA (rTKA) outcomes in SOT patients. METHODS: This was a retrospective review utilizing the Nationwide Readmissions Database (NRD) and ICD-9 codes to identify patients who underwent rTKA from 2010-2014 with a history of at least one SOT. Propensity-score-matching (PSM) was used to compare rTKA outcomes in SOT patients compared to matched patients without SOT. RESULTS: A total of 303,867 rTKAs, with 464 of those being performed in SOT patients, were included in the study. Of these, 71,903 and 182 were performed for PJI in non-SOT and SOT patients, respectively. rTKA was performed most frequently in kidney transplant patients (53.0%) followed by liver transplant patients (34.3%). For non-PJI patients, SOT patients had a higher 90-day readmission rate than matched non-SOT rTKA patients (23.2% vs 12.6%, p = 0.006). However, there were no differences in 90-day readmission rates for specific rTKA complications, subsequent revision rTKA, or mortality. Among patients undergoing rTKA for PJI, there was no difference in overall 90-day readmission rate, readmission for specific rTKA complications, subsequent revision rTKA, or mortality. CONCLUSIONS: While the increased medical comorbidities associated with SOT place patients at increased risk for complications following rTKA, it appears that SOT alone does not do so when patients are matched based on overall medical comorbidity.