Faculty Bibliography

BACKGROUND:Periprosthetic joint infection (PJI) is a high-cost and extremely morbid complication following total joint arthroplasty (TJA); thus, developing a better understanding of perioperative infection prevention strategies is prudent. Literature is mixed regarding the efficacy of vancomycin powder and dilute povidone-iodine lavage, and limited on the combination thereof. To our knowledge, no prospective orthopaedic clinical trials to date have evaluated the efficacy of local vancomycin powder, dilute povidone-iodine lavage, or a combination vancomycin-povidone-iodine-protocol (VPIP) against normal saline irrigation. METHODS:In a large, prospective, multi-center, randomized-controlled study, four distinct infection prevention strategies were implemented in high-risk TJA patients. Local vancomycin powder, dilute povidone-iodine solution, combined VPIP, and saline control were used. Primary outcomes included PJI, wound complications, revisions, emergency department (ED) visits, readmissions, and serious adverse events within three months of index surgery. Chi-square tests were used to compare incidence rates. The criteria used for the diagnosis of PJI were the International Consensus Meeting (ICM) guidelines. RESULTS:There were 821 total hip arthroplasty (THA) and 1,080 total knee arthroplasty (TKA) patients randomized into well-balanced study groups. In the THA and TKA cohorts, respectively, there were no statistically significant differences in rates of persistent wound drainage or dehiscence (P = 0.98, P = 0.95), cellulitis or abscess (P = 0.81, P = 0.51), 3-month infection rates (P = 0.14, P = 0.13), type of septic revisions performed (P = 0.51, P = 0.80), aseptic revision rates (P = 0.07, P = 0.90), ED visits (P = 0.61, P = 0.46), or readmissions (P = 0.78, P = 0.87) between the four treatment groups. CONCLUSIONS:There were no statistically significant differences in PJI or other surgical outcomes following THA or TKA among the study groups. Therefore, the use of such prophylactic measures, including povidone-iodine and vancomycin powder in high-risk patients, can be left up to the surgeon or hospital discretion.

INTRODUCTION/BACKGROUND:Modular dual mobility (DM) liners are commonly used in total hip arthroplasty (THA) to decrease the risk of instability. However, there are concerns about accelerated wear, corrosion, and metal ion release in modular DM constructs. This study aimed to investigate serum metal ion levels over time after THA and evaluate any differences between implant manufacturers. METHODS:This retrospective study enrolled 165 patients who underwent THA with a modular DM liner. Serum cobalt (Co), chromium (Cr), and zirconium (Zr) levels were assessed via a one-time blood draw. Patients were grouped into time cohorts of one to two, two to five, five to eight, and eight plus years based on years since DM placement. The primary outcome was serum Co, Cr, and Zr levels. Reference values of < 1.5 mcg/L for Co and < 1.2 mcg/L for Cr were considered within normal limits. RESULTS:Median Co and Cr levels were 0.3 (range, 0.2 to seven) and 0.3 (range, zero to 3.1) mcg/L, respectively. There were 13 patients (7.9%) who had abnormally elevated metal ion levels; 10 received Implant A (13%), two received Implant B (4%), and one received Implant C (3%). The Zr levels were undetectable in all patients. Median Co levels (0.4 mcg/L) were higher within two years of DM implantation and had a greater range of values than other time periods (P < 0.001). Successive time periods displayed a decreased range of Co values over time. CONCLUSION/CONCLUSIONS:There was a greater range of Co levels within two years of implantation, which reduced in variability over successive time periods. Although this could suggest an initial "settling-in" period of DM constructs, sequential blood draws from individual patients over time are needed to confirm such trends. Longitudinal tracking of metal ion levels over time in modular DM implants is recommended.

INTRODUCTION/BACKGROUND:Maintaining follow-up after total joint arthroplasty (TJA) is critical to monitor patient outcomes and complications. However, patient factors associated with follow-up compliance have not been described previously. This study aimed to characterize demographic and perioperative characteristics associated with TJA follow-up compliance. METHODS:This was a retrospective review of all primary, elective total hip and knee arthroplasty (THA and TKA) procedures at an urban, tertiary care center from 2011 to 2022. Patient follow-ups were categorized as early (0 to 90 days), mid-term (91 days to two years), and late-term (greater than two years). Patient characteristics, including age, sex, race, smoking status, spoken language, body mass index, income class, insurance type, distance from hospital, 90-day readmission, American Society of Anesthesia Status, and Charlson Comorbidity Index (CCI), were compared at each period, and logistic regression identified predictors of follow-up. RESULTS:In total, 2,836 TKA and 3,056 THA procedures were analyzed, with overall follow-up rates of 78.9 and 76.8%, respectively. Among all TJA patients, those who did not have follow-up were more likely to be younger, men, White, active smokers, live further from the hospital, and have lower CCIs. Uniquely, for TKA patients, higher income status predicted lower overall and early follow-up rates, while English-speaking predicted lower early and higher late follow-up rates in this subgroup. Differences between groups based on follow-up status decreased as follow-up time increased. Regression analyses showed loss to follow-up increased with increased distance from the hospital and current smoking. Uniquely, for THA, men predicted loss-to-follow-up. CONCLUSION/CONCLUSIONS:Younger age, men, White race, higher income, current smoking, and increased distance from the hospital are associated with increased early, but not late, loss to follow-up after TJA. Future studies should assess the influence of other factors, including home support and telemedicine use, on follow-up rates.

INTRODUCTION/BACKGROUND:The purpose of this multicenter, double-blinded, prospective, randomized controlled trial was to determine the safest and most effective dose of intravenous (IV) dexamethasone administered during primary total knee arthroplasty (TKA). METHODS:There were 404 patients undergoing inpatient primary TKA randomized across 11 centers to receive four mg (n = 138), eight mg (n = 137), or 16 mg (n = 129) of IV dexamethasone intraoperatively. All sites utilized the same perioperative multimodal protocol. Opioid consumption measured in morphine milligram equivalents (MME), pain scores, nausea scores, vomiting episodes, and sleep duration was collected for seven days postoperatively. Glucose levels were measured on postoperative day (POD) one. The mean age was 68 years, the mean body mass index was 33, and 62% were women. Independent sample t-tests were used for continuous data, and Chi-square and Fisher's exact tests were used for discrete data. Demographic characteristics were comparable between groups, suggesting successful randomization. RESULTS:Patients who received 16 mg IV dexamethasone consumed less MME on POD one (38 versus 37 versus 27 MME; P = 0.047) and had fewer vomiting episodes (P = 0.02). Patients who received 16 mg also had lower pain scores at rest at 24 hours, 48 hours, and one week. There were no differences in cumulative opioid consumption within the first 48 hours (P = 0.24), one week (P = 0.43), or pain with activity at any time point. The POD one glucose was highest in patients who received 16 mg (P < 0.001). There were no differences in length of stay, hours slept, or 90-day complication rates between groups. CONCLUSION/CONCLUSIONS:High-dose (16 mg) IV dexamethasone in TKA reduces opioid consumption, pain, and vomiting on the first day after surgery. Outcomes, including opioid consumption, sleep, and nausea, are comparable beyond 24 hours for all doses.

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.

BACKGROUND:Optimal femoral stem alignment and femoral canal fill have been associated with improved osteointegration in patients undergoing cementless total hip arthroplasty (THA). Direct anterior approach (DAA) has become more popular among new surgeons, and the ability to achieve appropriate stem alignment and canal fill due to limited surgical exposure may pose added risks. To mitigate these concerns, several modern tissue sparing stem designs have been designed. This study aimed to compare implant canal fill and alignment between two of the leading DAA-friendly femoral stems available. METHODS:This was a multi-center, retrospective study of patients who underwent DAA THA with either A (n = 149) or B stem (n = 85) between 2021 and 2023 and had a minimum one-year follow-up. Radiographic measures of proximal femoral morphology, including canal calcar ratio (CCR), Morphological Cortical Index (MCI), and Dorr Class (based on the CCR), as well as postoperative measures including femoral canal fill ratio (CFR), signs of osteointegration and stem alignment were analyzed and compared between stem types. RESULTS:, p = 0.082). Spot weld formation was significantly higher in stem A group (59.7% vs. 37.6%, P = 0.001). CONCLUSION/CONCLUSIONS:For patients with similar femoral morphology undergoing DAA THA, the stem A group demonstrated superior anatomical fit in the metaphyseal region, as evidenced by CFR, spot weld formation and implant positioning. Further longer follow up research is needed to elucidate these findings and their correlation to clinical outcomes.

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.

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:Methylene blue (MB), a phenothiazine dye with antimicrobial activity, is used to stain soft tissues and guide thoroughness of debridement during revision total knee arthroplasty (rTKA) for periprosthetic joint infection (PJI). The purpose of this study was to determine if instillation of MB prior to arthrotomy impacts culture yield in TKA PJI. METHODS:We retrospectively reviewed 266 patients diagnosed with TKA PJIs according to the 2018 International Consensus Meeting (ICM) criteria from January 2018 - March 2023 at a single academic hospital. Demographics, perioperative outcomes, and preoperative and intraoperative culture positivity were compared between patients who received intraoperative MB (MB group; n = 26) and those who did not (nMB group; n = 241). A record of detected organisms was included in the analysis. RESULTS:There was no difference in preoperative aspiration culture positivity between groups. However, the MB group had a higher percentage of preoperative to intraoperative culture concordance (89.5 vs. 69.9%; P = 0.04). Although the overall rate of intraoperative culture positivity did not differ significantly between groups, the MB group had more intraoperative cultures obtained per patient (4.9 vs. 4.5; P = 0.02) and higher numbers of positive intraoperative cultures per patient. Concordance rates for patients in both groups with positive preoperative and negative intraoperative cultures were similar (10.5 vs. 16.5%, P = 0.50). Among patients with negative preoperative cultures, intraoperative culture positivity was more discordant in the MB group (0 vs. 18.8%; P = 0.03). There was no difference in the number of patients that received antibiotics following aspiration (68.4 vs. 49.6%; P = 0.12). CONCLUSION/CONCLUSIONS:While MB use did not affect overall culture positivity, it could interfere with intraoperative pathogen detection in patients with negative preoperative cultures. In these cases, MB should be avoided to decrease inaccuracies in intraoperative culture yield. If preoperative cultures are positive, MB may improve surgical debridement and likelihood of infection eradication.

BACKGROUND:Changing from standing to sitting positions requires rotation of the femur from an almost vertical plane to the horizontal plane. Osteoarthritis of the hip limits hip extension, resulting in less ability to recruit spinopelvic tilt (SPT) while standing and requiring increased SPT while sitting to compensate for the loss of hip range of motion. To date, the effect of total hip arthroplasty (THA) on spinopelvic sitting and standing mechanics has not been reported, particularly in the setting of patients with coexistent sagittal plane spinal deformity. METHODS:A retrospective review was performed of patients ≥18 years of age undergoing unilateral THA for hip osteoarthritis with sitting and standing radiographs made before and after THA. Alignment was analyzed at baseline and follow-up after THA in both standing and sitting positions in a relaxed posture with the fingers resting on top of the clavicles. Patients were grouped according to the presence or absence of sagittal plane deformity preoperatively into 3 groups: no sagittal plane deformity (normal), thoracolumbar (TL) deformity (pelvic incidence-lumbar lordosis [PI-LL] mismatch > 10° and/or T1-pelvic angle [TPA] > 20°), or apparent deformity (PI-LL ≤ 10° and TPA ≤ 20°, but sagittal vertical axis [SVA] > 50 mm). RESULTS:In this study, 192 patients were assessed: 64 had TL deformity, 39 had apparent deformity, and 89 had normal alignment. Overall, patients demonstrated a reduction in standing SVA (45 to 34.1 mm; p < 0.001) and an increase in SPT (14.6° to 15.7°; p = 0.03) after THA. There was a greater change in standing SVA (p < 0.001) among patients with apparent deformity (-29.0 mm) compared with patients with normal alignment (0.9 mm) and patients with TL deformity (-16.3 mm). Those with apparent deformity also experienced the greatest difference (p = 0.03) in postural SPT change (moving from standing to sitting) (-10.1°) from before to after THA when compared with those with normal alignment (-3.6°) and TL deformity (-1.2°). The difference in postural SVA change from before to after THA was also greatest (p < 0.001) in those with apparent deformity (32.1 mm) compared with those with normal alignment (6.5 mm) and TL deformity (17.3 mm). CONCLUSIONS:Postural changes in spinopelvic alignment vary after THA depending on the presence of TL deformity or apparent deformity due to hip flexion contracture. Patients with apparent deformity had larger changes in standing and sitting alignment than patients with TL deformity or patients with normal alignment. The assessment of global sagittal alignment findings can be used to predict the likelihood of improvement in sagittal alignment after THA. LEVEL OF EVIDENCE/METHODS:Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.