Faculty Bibliography

BACKGROUND:Recovery after total knee arthroplasty (TKA) shows considerable variability in both pain relief and functional improvement. The Knee Injury and Osteoarthritis Outcome Score (KOOS-JR) is a widely used measure for evaluating these outcomes. This study aimed to identify distinct latent recovery trajectories, which represent underlying, unobserved patterns of postoperative recovery inferred from KOOS-JR scores, and to explore patient characteristics associated with these trajectories. METHODS:This retrospective cohort study analyzed patients who underwent primary TKA for osteoarthritis at a tertiary academic center from January 2020 to March 2023. Inclusion criteria required patients to have completed a preoperative KOOS-JR questionnaire and at least two postoperative follow-ups at 1, 3, 6, or 12 months. Exclusion criteria included bilateral or revision procedures. Collected characteristics included age, sex, Body Mass Index, American Society of Anesthesiologists physical status classification, race, smoking status, procedure type, anesthesia type, length of hospital stay, and discharge disposition. Growth mixture modeling was used to model recovery trajectories, with associations evaluated using the "three-step approach." Model fit was assessed using the Akaike and Bayesian Information Criteria, Vuong-Lo-Mendell-Rubin likelihood ratio, posterior probabilities, and entropy values. RESULTS:Of 700 eligible patients, growth mixture modeling identified two recovery trajectories: 95.4% of patients (trajectory 1 [T1]) demonstrated steady improvement, while 4.6% (trajectory 2 [T2]) began with lower KOOS-JR scores (mean 9.7 vs. 47.9 for T1) but recovered to near T1 levels by 1 month. Trajectory 2 patients were markedly younger (mean 64 vs. 67 years), had higher Body Mass Index (36 vs. 31), included more Black or African American individuals (38% vs. 20%), and were more frequently discharged to rehabilitation facilities (16% vs. 3.3%; all P < 0.05). Each additional year of age reduced the likelihood of following T2 by 4% (odds ratio = 0.96, 95% confidence interval, 0.92 to 0.99; P = 0.016), while discharge to rehabilitation increased the likelihood 6-fold (odds ratio = 6.22, 95% confidence interval, 1.89 to 17.8; P = 0.001). CONCLUSION/CONCLUSIONS:This study identified two distinct recovery trajectories after TKA, with notably no trajectory emerging showing decline or stagnation from preoperative levels. Despite lower baseline scores, patients in T2 achieved substantial recovery, suggesting TKA provides meaningful improvement even for those with substantially compromised function. The findings also highlight the need to explore whether rehabilitation discharge directly influences the observed postoperative gains.

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: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.

INTRODUCTION/BACKGROUND:Total knee arthroplasty can substantially affect global lower limb alignment. However, its specific impacts on ankle and subtalar joint alignment remain poorly understood. This study investigates changes in ankle and subtalar alignment following varying degrees of varus/valgus knee correction in order to further our understanding of this association. MATERIALS AND METHODS/METHODS:This retrospective study included 100 patients who underwent surgery for primary osteoarthritis. Patients diagnosed with conditions other than primary knee OA and those with incomplete or poor-quality imaging were excluded. Patients were categorized into four groups by the degree of intraoperative coronal knee alignment correction: Group 1 (< 10° varus, n = 37), Group 2 (≥ 10° varus, n = 30), Group 3 (< 10° valgus, n = 18), and Group 4 (≥ 10° valgus, n = 15). Hip-knee-ankle angle, tibial plafond inclination, talar inclination, tibiotalar tilt, and subtalar varus-valgus angle, were measured preoperatively and postoperatively on full-length, standing, anteroposterior X-ray images. RESULTS:TKA resulted in postoperative changes in all measured angles regardless of the degree of varus/valgus correction. Notably, ≥ 10° valgus correction led to statistically significant postoperative alterations in ankle and subtalar alignment: tibial plafond inclination from 84.9 to 89.5° (Δ 4.6, range,1.5-7.8, P <.01), tibiotalar tilt from 83.1 to 89.3° (Δ 6.2, range,1.1-9.6, P =.02), and subtalar varus-valgus angle from 66.4 to 72.6° (Δ 6.2, range,1.9-12.1, P <.01). CONCLUSION/CONCLUSIONS:While knee deformity correction during TKA generally realigns the ankle and subtalar joint, our study has shown that large valgus knee correction (≥ 10°) during TKA significantly alters ankle and subtalar joint alignment. Thus, potentially leading to unfavorable postoperative outcomes in patients with abnormal or stiff joints. We recommend that future studies investigate the long-term effects of large valgus knee corrections during TKA on ankle and subtalar joint alignment and their impact on postoperative outcomes.

BACKGROUND:Robotic assistance (RA) is increasingly used in total knee arthroplasty (TKA) for more accurate bony resection and balancing. However, the impact of robotic TKA (RATKA) on clinical outcomes and patient-reported measures (PROMs) remains unclear. This study aims to compare RATKA and conventional TKA (CTKA) using a novel robotic system. METHODS:A retrospective review was conducted on 10,031 patients who underwent TKA from February 2021 to October 2024. 289 RATKAs were performed with a hand-held robotic system. These RATKA cases were 1:1 propensity-score matched to CTKA for patient demographics, surgeon, implant system, and articulation design. Postoperative and clinical outcomes including surgical time, length of stay (LOS), discharge disposition, 90-day emergency department (ED) visits, manipulation under anesthesia (MUA), debridement, reoperations and revisions were collected and analyzed. Patient-reported outcomes measures (PROMs) included Knee Injury and Osteoarthritis Outcome Scores (KOOS, JR) and Patient Reported Outcome Measurement Information System (PROMIS) scores. RESULTS:RATKA demonstrated significantly shorter LOS (30.04 vs. 51.91 hours, p < 0.001, respectively) compared to CTKA. There was no difference in surgical time (107.18 vs. 106.22 minutes, p = 0.349). Although there was no statistical difference in 90-day ED visits, the majority of the CTKA revisits were due to surgery-related causes when compared to the RATKAs (1.38% vs. 0.34%, p = 0.239). While RATKAs had higher incidence of MUAs (2.07% vs. 0.34%, p = 0.201), CTKAs had more reoperations (1 vs. 0, p = 0.369) and more revisions than the RATKAs (6 vs. 0, p = 0.117). In terms of PROMs, both RATKAs and CTKAs showed similar improvements in KOOS, JR and PROMIS pain scores following TKA, with no significant differences in the magnitude of improvement at early postoperative timepoints. However, at the one-year follow-up, RATKA demonstrated significantly greater reduction in PROMIS pain intensity (Δ-9.12, p = 0.032) compared to CTKAs. CONCLUSIONS:This retrospective analysis showed that the novel RATKA resulted in reduced length of stay, fewer reoperations, and greater reduction in one-year PROMIS pain intensity compared to CTKAs, despite having a higher incidence of MUA rates. Further research is needed to clarify these differences clinically and enhance patient outcomes.

BACKGROUND:Arthrofibrosis is a debilitating complication of total knee arthroplasty (TKA) and may benefit from arthroscopic lysis of adhesions (LOA) to improve range of motion and decrease pain. However, the rates of periprosthetic joint infection (PJI) and of the need for future revision TKA (rTKA) have only been studied in a limited capacity in the literature. In this study, we aimed to compare PJI and revision outcomes in patients who had undergone TKA between those who subsequently underwent arthroscopic LOA and those who did not undergo arthroscopic LOA. METHODS:The PearlDiver database was utilized to identify patients who had undergone primary TKA between 2016 and 2021. ICD-10 (International Classification of Diseases, Tenth Revision) and CPT (Current Procedural Terminology) codes were then used to identify patients who underwent LOA for arthrofibrosis. The rates of PJI and rTKA were compared between patients who did and did not undergo LOA. Multivariable logistic and Cox regressions, controlling for age, sex, Charlson Comorbidity Index, tobacco use, and a body mass index of >30 kg/m2, were performed to compare the rates of PJI and revision between the LOA and no-LOA groups. RESULTS:A total of 383,143 patients were identified, of whom 703 had undergone arthroscopic LOA. Patients who underwent LOA had higher overall rates of PJI (2.7% versus 1.3%; p = 0.001) and all-cause revision (9.8% versus 1.8%; p < 0.001) than those who did not. Patients who underwent LOA had significantly higher odds of PJI (odds ratio [OR], 2.00; p < 0.014), aseptic loosening-related revision (OR, 3.31; p = 0.002), and all-cause revision (OR, 5.32; p < 0.001) within 1 year after the initial TKA. There was no significant difference in 1-year PJI-related revisions between the groups (OR, 1.71; p = 0.193). In a time-to-event analysis, patients undergoing LOA had significantly higher risks of PJI (p = 0.003) and all-cause revision (p = 0.001) but not PJI-related revision (p = 0.322) or aseptic loosening-related revision (p = 0.111). CONCLUSIONS:Arthroscopic LOA after primary TKA was associated with higher rates of PJI and subsequent revision surgery. Surgeons should consider the results of these studies when counseling patients on the importance of early rehabilitation and improving modifiable risk factors after TKA. LEVEL OF EVIDENCE/METHODS:Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

AIMS/UNASSIGNED:The aim of this study was to assess the variations in the positioning of components between sides in patients who underwent staged bilateral total hip arthroplasty (THA), and whether these variations affected patient-reported outcome measures (PROMs). METHODS/UNASSIGNED:A retrospective review included 207 patients who underwent staged bilateral THA between June 2017 and November 2022. Leg length, the height and anteversion of the acetabular component, and the coronal and sagittal angles of the femoral component were assessed radiologically and compared with the contralateral THA. The effect of the surgical approach and the technology used on this variation was also assessed. Linear regression was used to investigate the variations between the two THAs and the PROMs. RESULTS/UNASSIGNED:Between the two sides, the mean leg length varied by 4.6 mm (0.0 to 21.2), the mean height of the acetabular component varied by 3.3 mm (0.0 to 13.7), the mean anteversion varied by 8.2° (0.0° to 28.7°), the mean coronal alignment of the femoral component varied by 1.1° (0.0° to 6.9°), and the mean sagittal alignment varied by 2.3° (0.0° to 10.5°). The use of the direct anterior approach resulted in significantly more variation in the alignment of the femoral component in both the coronal (1.3° vs 1.0°; p = 0.036) and sagittal planes (2.8° vs 2.0°; p = 0.012) compared with the use of the posterior approach. The posterior approach generally led to more anteversion of the acetabular component than the anterior approach. The use of robotics or navigation for positioning the acetabular compoment did not increase side-to-side variations in acetabular component-related positioning or leg length. Despite considerable side-to-side variations, the mean Hip disability and Osteoarthritis Outcome, Joint Replacement (HOOS JR) score was not affected by variations in the postioning of the components. CONCLUSION/UNASSIGNED:Staged bilateral THA resulted in considerable variation in the positioning of the components between the two sides. The direct anterior approach led to more variations in anteversion of the acetabular component and sagittal alignment of the femoral component than the posterior approach. The use of computer navigation and robotics did not improve the consistency of the positioning of the components in bilateral THA. Variations in the positioning of the components was not associated with differences in PROMs, indicating that patients can tolerate these differences.

The efficacy of "Expanded Gram-Negative Antimicrobial Prophylaxis" (EGNAP) in preventing postoperative infections has been previously reported in total hip arthroplasty (THA). However, it remains unclear as to whether these benefits extend to total knee arthroplasty (TKA). This study investigated whether adding EGNAP to our institution's preoperative antibiotic prophylaxis protocol would affect periprosthetic joint infection (PJI) risk in TKA patients. We retrospectively reviewed 10,666 elective, unilateral, primary TKA cases performed at a single-specialty tertiary academic hospital from 2018 to 2022. Before June 2021, all patients received 2 g of cefazolin for 24 h as part of the prophylactic antibiotic protocol. After June 2021, gentamicin or aztreonam (EGNAP) was added to the protocol for all TKA patients. Patients were grouped based on whether they received EGNAP or not (control group) before surgery. The groups were propensity score-matched in a 2:1 ratio. PJI and nephrotoxicity (using RIFLE criteria) risk was compared. After matching, the final study population consisted of 3007 patients in the non-EGNAP group and 1503 patients in the EGNAP group. There was no significant difference between the EGNAP and no EGNAP groups in the overall incidence of PJI (1.9% vs. 2.0%; p = 0.111) or the incidence of Gram-positive PJIs (0.3% vs. 0.8%; p = 0.103). The incidence of Gram-negative PJIs was 0.5% in the EGNAP group and 0.4% in the no EGNAP group, which was also not different between the groups (p = 0.692). There were no differences in nephrotoxicity between groups (p = 0.521). The addition of EGNAP to the antibiotic prophylactic protocol prior to TKA had no effect on overall or Gram-negative PJI risk in TKA patients. The findings of this study suggest that while EGNAP is safe to use and has minimal nephrotoxic effects, its prophylactic benefits do not extend to the primary TKA population. This may be attributed to the generally low rate of Gram-negative infections in TKA patients, where adding EGNAP does not provide a clear advantage in reducing the risk of such infections, unlike its potential benefits in primary THA population. This study investigates the effects of using prophylactic Gram-negative antibiotics prior to TKA and shows that though it is safe to use, Gram-negative bacterial coverage may have no impact on postoperative infection incidence.

INTRODUCTION/BACKGROUND:Previous studies have identified perioperative gastric aspiration events as a contributor to varying outcomes following orthopedic trauma patients. However, current literature does not report on the effect an aspiration event has on outcomes for patients undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA), nor do current studies identify risk factors for perioperative aspiration events. MATERIALS AND METHODS/METHODS:We retrospectively reviewed patients who underwent primary, unilateral total joint arthroplasty (TJA) from May 2011 to December 2021. Patients undergoing primary THA/TKA for fracture and oncological indications were excluded. A total of 35,108 patients were stratified according to no aspiration event (35,077 patients) or perioperative aspiration event (intraoperative, day zero, to day seven, 31 patients). Patient demographics and clinical outcomes data were collected and compared. RESULTS:The perioperative aspiration group had a higher average Charlson Comorbidity Index (CCI) (4.03 vs. 2.96, p = 0.008). The aspiration group was more likely to be placed in a lateral decubitus position (54.8% vs. 30.5%, p = 0.003). Patients experiencing an aspiration event had a longer length of stay (LOS) (5.74 vs. 2.66, p < 0.001) and lower rates of home discharge (58.1% vs. 82.5%; p < 0.001). No difference in adverse outcomes such as rate of readmission, revision, and mortality were observed between groups. Multivariable regressions did not show significantly higher odds of aspiration based on surgery type, positioning, or any other demographic factors. CONCLUSION/CONCLUSIONS:This study demonstrates that patients experiencing a perioperative aspiration event during or immediately following TJA do not incur higher rates of readmission, revision, or mortality if treated in a timely manner. However, they do incur longer LOS and higher non-home discharge rates. Further research can explore non-demographic risk factors for perioperative aspiration.

BACKGROUND:Two-stage revisions for chronic periprosthetic joint infections (PJIs) often include antibiotic-loaded cement spacers to control for infection and preserve function. While studies have reported on complications (dislocations, readmissions, and reoperations) after static versus articulating spacer types, there is a paucity of evidence about whether the degree of spacer constraint in articulating spacers affects these complications. This study aims to address a key gap in understanding as to whether the level of spacer constraint affects complications in two-stage revision THA utilizing articulating spacers. QUESTIONS/PURPOSES/OBJECTIVE:(1) Among patients receiving nonconstrained versus constrained articulating antibiotic spacers during first-stage revision THA for PJI, are there differences in major complications, such as dislocation, loosening, periprosthetic fracture, reinfection, and unplanned revisions? (2) After second-stage reimplantation, do patients who received a nonconstrained versus constrained liner during the first stage show differences in the risk of complications, reoperations, and readmissions? METHODS:This is a retrospective review of 539 patients who underwent two-stage revision THA for PJI at a single-specialty, urban academic referral center between July 2011 and March 2023. Of these 539 patients, 72% (388) were excluded for undergoing a full component revision (femoral or acetabular) for any reason before their first stage, 3% (15) for receiving static spacers, and 6% (35) for receiving prefabricated femoral mono-block stems as part of their first stage. Those who underwent only liner exchange were not excluded. The remaining 19% (101 of 539) of patients were included in the final analysis and categorized by degree of liner constraint: 32 were in the nonconstrained group and 69 were in the constrained group. All surgeons included in this study specialize in adult reconstruction and are fellowship trained, and the selected level of constraint was solely based on their routine practice for articulating spacer construct. Baseline characteristics and clinical data, including age, self-reported gender, race, BMI, American Society of Anesthesiologists score, smoking status, surgical history, and perioperative details, were collected. There were no differences in baseline characteristics between the groups except for smoking status. A priori power analysis determined that 150 patients (75 per group) would be needed to detect a statistical difference in the risk of dislocation between groups, assuming a 20% dislocation risk for the constrained group, at a 0.05 alpha level, and 80% power. RESULTS:Between patients receiving nonconstrained versus constrained liners, there were no differences in complications after the first stage of revision. Three percent (1 of 32) of the nonconstrained liners developed dislocations compared with 3% (2 of 69) in the constrained group (relative risk [RR] 1.1 [95% confidence interval (CI) 0.09 to 12.3]; p > 0.99). Three percent (1 of 32) of the nonconstrained group developed periprosthetic fractures compared with 7% (5 of 69) in the constrained group (RR 0.4 [95% CI 0.05 to 3.69]; p = 0.72). Similarly, 3% (1 of 32) versus 7% (5 of 69) had persistent infection (RR 0.4 [95% CI 0.05 to 3.69]; p = 0.72). One incident of loosening occurred in the constrained group. There were also no differences in spacer revision incidence: 10% (3 of 32) of the nonconstrained group and 10% (7 of 69) of the constrained group underwent an unplanned revision after the first stage (RR 1.0 [95% CI 0.29 to 3.91]; p = 0.91). For the second stage, dislocation was 14% (3 of 21) in the nonconstrained group and 10% (5 of 52) in the constrained group (RR 1.1 [95% CI 0.2 to 5.9]; p > 0.99). When comparing periprosthetic fractures, 10% (2 of 21) of the nonconstrained group developed periprosthetic fractures compared with 4% (2 of 52) in the constrained group (RR 2.2 [95% CI 0.3 to 16.6]; p = 0.78). Nineteen percent (4 of 21) in the nonconstrained group had persistent infection compared with 12% (6 of 52) in the constrained group (RR 1.5 [95% CI 0.39 to 5.74]; p = 0.81). The occurrence of readmission after the second stage was 19% (4 of 21) in the nonconstrained group compared with 15% (8 of 52) in the constrained group (RR 1.1 [95% CI 0.3 to 3.9]; p > 0.99). Twenty-four percent (5 of 21) of patients in the nonconstrained group required a surgery-related emergency department visit compared with 13% (7 of 52) in the constrained group (RR 1.6 [95% CI 0.4 to 5.6]; p = 0.64). The incidence of reoperation was 14% (3 of 21) in the nonconstrained group and 13% (7 of 52) in the constrained group (RR 0.9 [95% CI 0.2 to 3.8]; p > 0.99). CONCLUSION/CONCLUSIONS:Our results indicated no differences in the risk of dislocations, reinfections, reoperations, and readmissions between patients undergoing constrained versus nonconstrained articulating spacers for two-stage revision THA. Because constrained liners are typically preferred in patients at higher risk of instability, our findings suggest that their use does not necessarily increase the risk of complications. However, because of the small sample size, larger studies are needed to demonstrate whether there is superiority of liner constraint in this patient population. LEVEL OF EVIDENCE/METHODS:Level III, therapeutic study.