Faculty Bibliography

BACKGROUND:Obesity and diabetes mellitus (DM) pose challenges for patients undergoing total knee arthroplasty (TKA). Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have emerged as agents for weight and DM management, but they affect multiple organ systems. Outcomes, trends, and demographics for perioperative GLP-1RA use in patients with TKA are not well understood. METHODS:A retrospective review of 13,751 primary, elective TKAs with at least 90 days of follow-up at an urban academic health system between 2012 and 2023 identified 865 patients who had perioperative GLP-1RA use. A 10:1 propensity score match based on sex, age, smoking status, American Society of Anesthesiologists classification, and body mass index created a control cohort of 8,650 TKAs with no GLP-1RA use. RESULTS:The use of GLP-1RAs varied significantly by race, Medicaid insurance, Charlson Comorbidity Index, and presence of DM. Black and Latino patients and those covered by Medicaid were significantly less likely to receive GLP-1RAs. The GLP-1RA group had significantly shorter length of stay (2.1 versus 2.5 days, P < 0.001) and a higher rate of home discharge (91.7 versus 84.2%, P < 0.001). The GLP-1RA users had significantly higher rates of 90-day emergency department visits (5.9 versus 4.0%, P = 0.008), but no differences in 90-day readmissions (4.3 versus 3.6%, P = 0.168) or 2-year revision (2.3 versus 2.6%, P = 0.362) compared to matched controls. The GLP-1RA patients had significantly lower all-cause revision rates at the last follow-up (2.7 versus 3.9%, P = 0.034), but there was no significant difference in Kaplan-Meier implant survival (P = 0.311). Before TKA, GLP-1RA patients had an average decrease in body mass index of 0.4, compared to an average increase of 1.2 for matched controls. CONCLUSIONS:Our results demonstrate that the use of GLP-1RAs is significantly lower for minority patients and those covered by Medicaid. Patients using GLP-1RAs have noninferior clinical outcomes with the potential for weight loss leading up to TKA. LEVEL OF EVIDENCE/METHODS:III.

BACKGROUND:The cementation technique is crucial for achieving adequate fixation and optimal survivorship in total knee arthroplasty (TKA). The thickness of the cement at the tibial bone-implant surface may be related to aseptic tibial loosening. However, to date, no studies have demonstrated a direct association between cement thickness and rates of aseptic tibial loosening. METHODS:We performed a retrospective review to identify 28,327 primary cemented TKAs with at least 2 years of follow-up at an academic health system from 2013 to 2021. A total of 115 cases underwent revision surgery for aseptic tibial loosening. Cases where the implant was recalled specifically for loosening (n = 23) were excluded. The remaining 92 aseptic tibial loosening cases were 2:1 propensity score matched and implant matched to control patients who did not have tibial loosening. There were two independent reviewers who then measured the thickness of the cement interface in 10 locations along the bone-implant interface from initial postoperative radiographs. The averages of the reviewers' measurements were calculated and then compared using independent t-tests. RESULTS:Aseptic tibial loosening cases involving implant A tibial baseplate (n = 75) had significantly thinner cement interfaces than matched controls at all the 10 locations measured. Aseptic loosening cases involving implant B (n = 17) also displayed a thinner cement interface than matched controls in all locations, but this result was only statistically significant at the medial baseplate, medial keel, lateral keel, anterior keel, and posterior baseplate. CONCLUSIONS:In two widely used TKA systems, tibial aseptic loosening was associated with significantly thinner cement interfaces when compared to propensity-matched controls in two different implant types. Further prospective studies are needed to identify the optimal keel preparation and design as well as minimal cement interface thickness to avoid implant loosening. LEVEL OF EVIDENCE/METHODS:III.

BACKGROUND:Social determinants strongly influence overall health, including recovery after total joint arthroplasty (TJA). The modern electronic health record includes a list of individuals identified by patients as their primary contacts. We aimed to assess whether the relationship between patients and their documented primary contacts was associated with outcomes after TJA. METHODS:We retrospectively reviewed primary, elective total hip arthroplasties (THAs) and total knee arthroplasties (TKAs) at a single institution from June 2011 to December 2022, and stratified patients into two groups: family (F) [familial relationships to include spouse, first, or second degree relative] or non-family (NF) [nonfamilial relationships, such as friend or neighbor] based on patient relationship to their primary emergency contact. Baseline characteristics and postoperative outcomes were compared. Binary logistic regression was utilized to assess variables associated with all-cause revision. In total, 17,520 THAs were included as follows: 16,123 (92.0%) in the F group and 1,397 (8.0%) in the NF group. Additionally, 20,397 TKAs were included as follows: 18,819 (92.3%) in the F group and 1,578 (7.7%) in the NF group. RESULTS:For both THA and TKA patients, having a NF primary contact was independently associated with a higher risk of all-cause revision at the latest follow-up (OR [odds ratio]: 1.48 [95% CI (confidence interval): 1.05 to 2.08], P = 0.025) and (OR: 1.62 [95% CI: 1.10 to 2.38], P = 0.014), respectively. In both THA and TKA, the F group had shorter lengths of stay (P < 0.001) and was more likely to be discharged home (P < 0.001) compared to the NF group. CONCLUSIONS:TJA patients who have a familial primary contact demonstrate better postoperative outcomes compared to those who do not have a familial contact. Awareness of social support and additional postoperative support for patients who have NF primary contacts may be warranted following TJA.

BACKGROUND:Recent literature suggests a trend toward a higher comorbidity burden in patients undergoing total knee arthroplasty (TKA). However, the impact of increased comorbidities on the cost-effectiveness of TKA is underexplored. This study aimed to compare the financial implications and perioperative outcomes of patients with and without a high comorbidity burden (HCB). METHODS:We retrospectively reviewed 10,647 patients who underwent elective, unilateral TKA between 2012 and 2021 at a single academic health center with available financial data. Patients were stratified into HCB (Charlson Comorbidity Index ≥ 5 and American Society of Anesthesiology scores of 3 or 4) and non-HCB groups. A 1:1 propensity match was performed based on baseline characteristics, resulting in 1,536 matched patients (768 per group). Revenue, costs, and contribution margins (CM) of the inpatient episode were compared between groups. Ninety-day readmissions and revisions were also analyzed. RESULTS:The HCB patients had significantly higher total (P < 0.001) and direct (P < 0.001) costs, while hospital revenue did not differ between cohorts (P = 0.638). This disparity resulted in a significantly decreased CM for the HCB group (P = 0.009). Additionally, HCB patients had a longer length of stay (P < 0.001) and a higher rate of 90-day readmissions (P = 0.005). CONCLUSIONS:Increased inpatient costs for HCB patients undergoing TKA were not offset by proportional revenue, leading to a decreased CM. Furthermore, higher 90-day readmissions exacerbate the financial burden. These findings highlight potential challenges for hospitals in covering indirect expenses, which could jeopardize accessibility to care for HCB patients. Reimbursement models should be revised to better account for the increased financial burden associated with managing HCB patients. LEVEL OF EVIDENCE/METHODS:III.

BACKGROUND:Traveling fellowships, such as the Hip Society Rothman-Ranawat fellowship, offer orthopaedic surgeons the opportunity to enhance their skills, conduct research, and gain mentorship at top orthopaedic centers. This study aimed to assess the impact of the Hip Society Rothman-Ranawat traveling fellowship on an adult reconstruction surgeon's career. METHODS:A non-incentivized online survey was distributed to the 40 past recipients of the Hip Society Rothman-Ranawat traveling fellowship spanning from 2013 to 2023. The survey comprised short-answer questions and multiple-choice questions to evaluate the impact of the traveling fellowship. Surgeon publication counts and h-indexes were extracted from the Scopus database before the fellowship and at intervals of three years, five years, and the present post fellowship. Quantitative metrics were adjusted based on the time elapsed since the surgeon completed the fellowship and compared using paired-sample t-tests. RESULTS:This study had a 95% response rate (n = 38). Following the completion of the fellowship, we observed an increase in publication count and h-index at various intervals compared to the time before the fellowship. The mean annual percentage increase in publication count was 25.6% at the 3-year mark, 37.6% at the 5-year mark, and 29.4% at the present time, all relative to the publication count before the fellowship. Similarly, the mean annual percentage increase in the h-index was 9.7% at the 3-year mark, 9.6% at the 5-year mark, and 4.1% at the present time, all compared to the h-index before the fellowship. Qualitative measures showed previous fellows endorsed that the fellowship positively changed their clinical practice (84% agreement), expanded their network (97% agreement), increased research productivity (82% agreement), and improved surgical technique (74% agreement). CONCLUSION/CONCLUSIONS:Responses from past Hip Society Rothman-Ranawat traveling fellows suggest that participating in the fellowship positively influenced their career trajectories.

BACKGROUND:Tranexamic acid (TXA) is a renally-excreted antifibrinolytic commonly utilized in total joint arthroplasty (TJA). This study examined whether TXA administration affected clinical outcomes and kidney function in patients who had end-stage renal disease (ESRD) undergoing TJA or hemiarthroplasty. METHODS:Through a retrospective chart review, we identified 123 patients: 40 who underwent primary elective total knee arthroplasty (TKA; 65% received TXA), 34 who underwent primary elective total hip arthroplasty (THA; 52.9% TXA), and 49 who underwent nonelective THA or hemiarthroplasty (44.9% TXA) from January 2011 to February 2024. All patients had ESRD and/or were on dialysis, with no difference in percentage on dialysis between TXA groups (TKA: 65.4 versus 64.3%; THA: 55.6 versus 50.0%; nonelective/hemiarthroplasty: 86.4 versus 85.2%, P values ≥ 0.586). Demographic and perioperative characteristics, including preoperative hemoglobin, TXA administration, dose, and route of administration (ROA; intravenous, topical), were extracted. Pre- and postoperative (≤ 7 days) creatinine, perioperative transfusions, revisions, and 90-day emergency department (ED) visits, readmissions, and mortalities were recorded and compared between TXA groups. RESULTS:In the total sample and all cohorts, change in pre- to postoperative creatinine and incidence of postoperative acute kidney injury (AKI), per Kidney Disease Improving Global Outcomes (KDIGO) guidelines, did not significantly differ based on receiving TXA (P values ≥ 0.159). Among patients receiving TXA, change in creatinine did not significantly differ by dose (P values ≥ 0.428) or ROA (P values ≥ 0.256). There were no statistically significant differences in 90-day ED visits, readmissions, or mortalities based on receiving TXA (P values ≥ 0.055). Thromboembolic events occurred in four patients (one TXA, three no TXA, P = 0.617), and perioperative transfusions occurred in two patients (one TXA, one no TXA, P = 0.882) in the nonelective/hemiarthroplasty cohort, with none in the elective cohorts. CONCLUSIONS:The administration of TXA does not portend a significant increase in complications for patients who have ESRD undergoing TJA or hemiarthroplasty for fracture, suggesting TXA should not be contraindicated in this population.

BACKGROUND:A tourniquet is commonly used during total knee arthroplasty (TKA) to improve surgical field visibility and minimize blood loss. While the short-term effects of tourniquet use on postoperative outcomes have been studied extensively and found to be minimal, its influence on longer-term outcomes remains underexplored. This study examined tourniquet use in TKA with up to five-year follow-up. METHODS:In this post hoc analysis of a randomized controlled trial, 227 patients who underwent primary TKA in the tourniquet (T) group (n = 112) or no tourniquet (NT) group (n = 115) were evaluated. Clinical outcomes and patient-reported outcome measures (PROMs) were compared between the two groups. RESULTS:The T group had non-significant trends toward reduced blood loss (131.8 versus 116.7 ml, P = 0.098) and shorter operative time (97.8 versus 95.7 minutes, P = 0.264), with slightly higher postoperative day-one Visual Analog Scale (VAS) pain scores (3.1 versus 3.6, P = 0.197). Length of stay (2.0 versus 2.1 days, P = 0.837) and home discharge rate (88.7 versus 92.0%, P = 0.340) were comparable. The NT group had three 90-day readmissions, while none occurred in the T group (2.7 versus 0%, P = 0.081). The active range of motion at the final follow-up was similar between groups (108.3 versus 106.5 degrees, P = 0.457). All-cause revision rates at five years were comparable between the NT and T groups (5.2 versus 3.6%, P = 0.546). Kaplan-Meier survivorship analysis revealed comparable aseptic implant survival at five years (P = 0.769). There were no significant differences in Knee injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS, JR), Patient-Reported Outcomes Measurement Information System (PROMIS) pain intensity, PROMIS pain interference, or PROMIS physical health scores at three months, one year, and five years postoperatively. CONCLUSION/CONCLUSIONS:Using a tourniquet during primary TKA was not associated with differences in clinical or patient-reported outcomes at up to five-year follow-up. These findings suggest that tourniquet use in TKA can be left to the surgeon's discretion.

BACKGROUND:Patient comorbidities can lead to worse outcomes and increase the risk of revisions after total hip arthroplasty (THA) and total knee arthroplasty (TKA). Sparse research is available on the effects of ostomies on postoperative outcomes. Our study aimed to assess whether patients who have ostomies, who underwent TKA or THA, have worse outcomes and increased rates of all-cause and periprosthetic joint infection (PJI)-related revisions. METHODS:We performed a retrospective cohort study comparing the outcomes of THA and TKA patients who have and do not have a history of ostomy using the Statewide Planning and Research Cooperative System. Patient demographics, ostomy diagnosis, 3-month emergency department visits and readmissions, and revisions were collected. A total of 126,414 THA and 216,037 TKA cases were included. Log-rank testing and a Cox proportional hazards model were used to account for covariates. RESULTS:In total, 463 THA patients (0.4%) had ostomies. They had a longer length of stay (4.0 versus 3.1 days, P < 0.001) and were less likely to be discharged home (55.3 versus 62.2%, P = 0.01). They had higher rates of PJI-related revisions (1.9 versus 0.9%, P = 0.02) and had increased odds of PJI-related revision (OR [odds ratio] = 2.2, P = 0.02). Of TKA patients, 619 patients (0.3%) had an ostomy. They had a longer length of stay (3.6 versus 3.3 days, P = 0.02) and was less likely to be discharged home (49.4 versus 52.4%, P = 0.16). However, there was no difference in the rate (1.8 versus 1.4%, P = 0.49) or odds (OR = 1.2, P = 0.53) of PJI-related revision. CONCLUSIONS:THA, but not TKA, patients who have ostomies have an increased risk of PJI-related revisions. The proximity of the surgical incision to the ostomy site may play a role in the risk of PJI in THA patients.

BACKGROUND:Modern surgical protocols, particularly the use of tranexamic acid (TXA), have reduced, but not eliminated, blood transfusions surrounding total hip arthroplasty (THA). Identifying patients at risk for transfusion remains important for risk reduction and to determine type and screen testing. METHODS:We reviewed 6,405 patients who underwent primary, unilateral THA between January 2014 and January 2023 at a single academic institution, received TXA, and had preoperative hemoglobin (Hgb) values. We compared demographics, baseline Hgb levels, and surgical details between patients who were and were not transfused. Data were analyzed utilizing multivariate regression and receiver operating characteristic curve analysis. RESULTS:The overall perioperative and intraoperative transfusion rates were 3.4 and 1.0%, respectively. Patients who were older, women, and American Society of Anesthesiologists class >II demonstrated an increased risk of transfusion. Risk of transfusion demonstrated an inverse correlation with preoperative Hgb levels, a bimodal association with body mass index, and a direct correlation with age, surgical time, and estimated blood loss on multivariate analysis. The receiver operating characteristic analysis demonstrated a preoperative Hgb cutoff of 12 g/dL for predicting any transfusion. Above the threshold of 12 g/dL, total and intraoperative transfusions were rare, with rates of 1.7 and 0.3%, respectively. Total and intraoperative transfusion rates with Hgb between 11 and 12 g/dL were 14.3 and 4.6%, respectively. Below 11 g/dL, total and intraoperative transfusion rates were 27.5 and 10.1%, respectively. CONCLUSIONS:In the age of TXA, blood transfusion is rare in THA when preoperative Hgb is >12 g/dL, challenging the need for universal type and screening. Conversely, patients who have Hgb < 11.0 g/dL, remain at substantial risk for transfusion. Between Hgb 11 and 12 g/dL, patient age, sex, body mass index, American Society of Anesthesiologists classification, anticipated estimated blood loss, and surgical time may help predict transfusion risk and the need for a perioperative type and screen. LEVEL OF EVIDENCE/METHODS:III.