Faculty Bibliography

BACKGROUND/UNASSIGNED:Dual-mobility (DM) articulations and porous acetabular shells are increasingly used to address instability and mechanical loosening in revision total hip arthroplasty (rTHA). However, reports of longer-term outcomes with the new generation of DM articulations and porous shells remain limited. Our study reports the use and outcomes of a cemented monoblock DM cup in a fully porous acetabular shell in complex rTHA cases with midterm follow-up. METHODS/UNASSIGNED:A retrospective study was conducted of rTHAs with an acetabular construct of a monoblock DM cup cemented into a fully porous acetabular shell between June 2016 and December 2019. Baseline demographics, operative information, and outcomes were gathered for a total of 55 patients. Ten patients died, and 4 were lost to follow-up at 5 years; 41 patients were included in the analysis of midterm outcomes. RESULTS/UNASSIGNED:The most common indications for rTHA were acetabular component loosening (43.6%), periprosthetic joint infection (PJI) (16.4%), dislocation (12.7%), and periprosthetic fracture (9.1%). Preoperative acetabular bone loss assessment found 43.7% type IIA, 9.1% IIB, 20.0% IIC, 23.6% IIIA, and 3.6% IIIB according to the Paprosky classification. Six patients (10.9%) were readmitted within 90 days for PJI (n = 5; 9.1%) or dislocation (n = 1; 1.8%). Four patients (9.8%) required revision of the construct: 2 for PJI, 1 case of instability, and 1 case of aseptic loosening of the acetabular component with significant acetabular bone loss. The average time to revision was 1.4 years (range, 0.1-3.8 years). The mean follow-up period was 6.4 years (range, 4.7-8.2 years). The cup in cup construct had an all-cause survivorship of 95.8% and 90.0% at 1 and 5 years, respectively, and aseptic survivorship rates of 97.9% and 94.7% at 1 and 5 years, respectively. CONCLUSIONS/UNASSIGNED:This cohort of 55 patients who underwent complex rTHA with a monoblock DM cup cemented into a porous acetabular shell exhibited reliable fixation and low revision rates. In complex revision cases where instability and inadequate fixation are concerns, these outcomes support continued consideration and use of this unique and durable construct.

INTRODUCTION/BACKGROUND:Patellar resurfacing in primary total knee arthroplasty (TKA) has been debated for decades. This study aimed to evaluate cost-effectiveness and clinical outcomes of patellar resurfacing in modern TKA at a high-volume arthroplasty center. METHODS:A retrospective study was conducted on 4,534 patients who underwent unilateral, elective, primary TKA from 2021 to 2024 at an urban academic institute. Patients were stratified by patellar resurfacing: resurfaced (n=3,753) or not (n=781). Baseline characteristics, operative costs [implants, anesthesia, operating room time], and postoperative outcomes (revision incidence) were collected. The median follow up was 2.0 years (1.0- 4.8). The individual cost of patellar component was adjusted for implant manufacturer and cementation out of total implant cost. Multivariable regression analysis determined added operating room time (ORT) due to patellar resurfacing, controlling for body-mass index, usage of robotics, navigation and cementation. Relative costs of added ORT and the patellar component were compared to total implant and procedure costs of patellar-resurfacing operations. RESULTS:The patellar component accounted for an average of 7.9% of the total implant cost in patellar-resurfacing operations. Patellar-resurfacing operations had longer operative times (112.2 vs. 105.4 minutes, P<0.001), and multivariable regression determined patellar resurfacing is associated with an added 6.3 minutes of total ORT (P<0.001). The patellar component implant cost and the cost of added ORT due to resurfacing accounted for 4.5% of the total procedure cost in resurfaced group. Resurfaced group had an overall 5% higher total operative cost than the non-resurfaced group. No differences existed in length of stay (LOS), discharge disposition, or all-cause and patella-specific revision incidence. CONCLUSION/CONCLUSIONS:We found that patellar resurfacing was associated with longer operative times and greater implant and procedure costs, although there was no effect on LOS, discharge disposition, or all-cause and patella-specific revision incidence. Ultimately, the decision to resurface the patella in primary TKA should be based on patient-specific indications and clinical judgment. However, it is important to consider the additional cost associated with this procedure.

BACKGROUND:This study evaluated functional limb-length (LL) and coronal-alignment preservation after revision total knee arthroplasty (rTKA) relative to contralateral and pre-rTKA baselines, examining their association with patient-reported outcome measures (PROMs). METHODS:We retrospectively reviewed 70 rTKA patients with pre- and post-rTKA full-length radiographs. Functional LL preservation was defined as ± 10 mm of the target. Patient-reported outcomes-including Knee injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS, JR) and Patient-Reported Outcomes Measurement Information System (PROMIS) Pain Intensity and Pain Interference-were compared across LL (shortened/preserved/over-lengthened) relative to contralateral/pre-rTKA baselines and coronal alignment (preserved/changed) categories. Indications included aseptic loosening (31.4%), instability (30.0%), arthrofibrosis (14.3%), periprosthetic joint infection (12.9%), and insert wear (11.4%). RESULTS:The post-rTKA LL was preserved relative to the contralateral LL in 68.6% of the patients and pre-rTKA LL in 47.1%. Coronal alignment was preserved in 64.3%. PROM improvements were comparable across categories (P > 0.05). When referencing the contralateral limb, only the over-lengthened cohort achieved the minimal clinically important difference (MCID) across all PROMs at three months; at one year, all cohorts achieved MCID for KOOS, JR, and pain intensity, but missed the pain interference threshold. When referencing the pre-rTKA state, preserved and over-lengthened cohorts achieved MCID across all PROMs at three months; at one year, all cohorts sustained the MCID across all three outcome domains. The preserved alignment cohort achieved MCID across all PROMs, while the changed alignment cohort missed the threshold for pain interference. CONCLUSIONS:Revision TKA preserved functional LL and coronal alignment in approximately two-thirds of cases. Although PROMs were comparable among categories, early MCID achievement was associated with over-lengthening relative to the contralateral limb and avoiding shortening relative to the pre-rTKA state. At one year, preserving pre-rTKA coronal alignment provided superior pain interference relief, sustained only when evaluated relative to the pre-rTKA baseline.

INTRODUCTION/BACKGROUND:Same-day discharge (SDD) following primary total hip arthroplasty (THA) is increasingly utilized and has been shown to be safe in appropriately selected patients. However, limited data compare whether specific patient risk factors for postoperative readmission exert different magnitudes of influence in the SDD versus in the non-same-day discharge (NSDD) cohorts. Identifying risk factors that disproportionately affect SDD patients may refine SDD selection criteria and improve postoperative safety.: METHODS: This retrospective cohort study evaluated 11,245 patients who underwent primary elective THA at a single institution between 2017 and 2024. Patients were grouped by discharge timing into SDD (n = 2,318) and NSDD (n = 8,927). The primary outcome was orthopaedic-related hospital readmission within 90 days. Multivariable logistic regression models were constructed separately for SDD and NSDD cohorts to identify independent predictors of readmission. Adjusted odds ratios were compared between cohorts using z-tests to assess differences in effect magnitude. A sub-analysis was performed among cases by high-volume surgeons (≥ 100 THAs/year). RESULTS:The SDD patients had a significantly lower 90-day readmission rate compared with NSDD patients (0.8 versus 2.1%, P < 0.001). In SDD patients, smoking (odds ratio (OR) 13.98, P < 0.01) and older age (OR 1.13, P < 0.01) were strongly associated with readmission, while women were protected. In NSDD patients, higher body mass index and American Society of Anesthesiologists score ≥ III increased readmission risk, whereas partner status, higher hemoglobin, and non-White race were protective. Effect-size comparisons demonstrated that smoking (z = 4.34, P < 0.001) and age (z = 3.65, P < 0.001) had stronger associations with readmission in SDD patients than in NSDD patients. Readmission etiologies were similar between groups. Findings were consistent in the high-volume surgeon sub-analysis. CONCLUSIONS:While SDD after primary THA is associated with low overall readmission rates, smoking and advanced age confer disproportionately greater readmission risk when same-day discharge is pursued. These findings suggest that smoking status and age may warrant additional attention during preoperative counseling and individualized same-day discharge decision-making, while recognizing that absolute readmission rates remain low.

INTRODUCTION/BACKGROUND:Sarcopenia, the loss of muscle mass and function, is closely linked to poor health and has been associated with inferior outcomes in total hip arthroplasty (THA). Psoas Muscle Index (PMI) is a radiographic metric inversely correlated with sarcopenia. It was hypothesized that low PMI patients would have worse outcomes following THA. METHODS:A retrospective review of 515 patients who underwent robotic primary THA between 2014 and 2022 at a single, urban, academic health system with 2-year follow-up data was performed. Psoas Muscle Index was calculated from preoperative computed tomography imaging of the pelvis. Patient baseline demographics, laboratory values, perioperative data, and outcomes were collected from chart review. RESULTS:Low PMI occurred in 56 (10.8%) of 515 patients. There were no differences in readmissions or reoperations (P = 0.51; P = 0.58). Low PMI was associated with higher HOOS, JR score at 2 weeks and greater improvement from baseline (P = 0.034; P = 0.037), as well as lower Patient-Reported Outcomes Measurement Information System Pain Intensity at 3 months and greater reductions from baseline (P = 0.038; P = 0.013). CONCLUSION/CONCLUSIONS:Psoas Muscle Index did not reliably predict surgical outcomes following THA, and low PMI was associated with better patient-reported outcome measures after surgery. Further investigation into other means of diagnosing sarcopenia may be warranted.

BACKGROUND/UNASSIGNED:Solid organ transplant (SOT) recipients undergoing total joint arthroplasty (TJA) may face elevated perioperative risk because of chronic immunosuppression, medical comorbidity, and organ-specific physiologic considerations. Although intravenous tranexamic acid (TXA) is widely used during TJA to reduce perioperative blood loss, evidence regarding outcomes among SOT recipients receiving TXA remains limited. METHODS/UNASSIGNED:A retrospective review was performed of 29,240 consecutive primary TJA patients who all received intraoperative intravenous TXA between June 2011 and March 2025. Patients undergoing unicompartmental knee arthroplasty, hemiarthroplasty, TJA for fracture, bilateral procedures, revision procedures, or those with less than 90 days of postoperative follow-up were excluded. SOT history was identified using diagnosis and procedural codes and verified by manual review. Outcomes included 90-day deep vein thrombosis (DVT), pulmonary embolism (PE), myocardial infarction (MI), operative time, and hospital length of stay (LOS). RESULTS/UNASSIGNED:Sixty-six patients with verified SOT were identified. The most common transplant types were kidney (59%), liver (24%), and heart (9%). One SOT patient experienced a 90-day VTE event compared with 95 control patients (1.5% versus 0.3%, P = 0.20). There were no PEs or MIs in the SOT cohort, compared with PE and MI rates of 0.2% and 0.01% in controls, respectively (P > 0.05 for both). Operative times were similar between groups (100.8 versus 108.5 min, P = 0.11), while LOS was significantly longer among SOT recipients (86.2 versus 43.8 h, P < 0.001). CONCLUSION/UNASSIGNED:In this retrospective cohort of primary TJA patients who all received intraoperative intravenous TXA, SOT recipients had low observed rates of VTE, PE, and MI. Because all patients received TXA and the SOT cohort was small, these findings should be interpreted as comparative observational safety data rather than evidence that TXA independently increases or does not increase thromboembolic risk in this population.

BACKGROUND:Patients with chronic kidney disease (CKD) and dialysis dependence represent high-risk populations with increased demand for total joint arthroplasty (TJA). We aimed to assess surgical outcomes of CKD and dialysis-dependent (DD) patients undergoing TJA. METHODS:A multicenter retrospective review of TJA records between June 2011 and July 2022 was conducted. Patients with a diagnosis of CKD who were DD at the time of surgery were propensity-matched to non-DD CKD patients and control subjects without CKD in a ratio of 1:5:5. Matched comparisons and Kaplan-Meier survival analyses were conducted for a total of 176 (DD: 16) total knee arthroplasty (TKA) and 297 (DD: 27) total hip arthroplasty (THA) patients. RESULTS:Medical complications within 90 days after both TKA (control: n = 1, 1.3%; CKD: n = 3, 3.8%; DD: n = 3, 18.8%; P = 0.005) and THA (control: n = 4, 3%; CKD: n = 4, 3%; DD: n = 6, 22.2%; P < 0.001) were significantly higher in the DD group. Infection and revision rates at last follow-up were similar between the three groups after TKA (P > 0.05) and THA (P > 0.05). In Kaplan-Meier analyses, survivorship free of mortality was lowest in the DD group after THA at 40.3% compared with 100% in the control and 78.8% in the CKD groups (P < 0.001). CONCLUSION/CONCLUSIONS:Dialysis-dependent patients are at an increased risk of postoperative medical complications and mortality compared with matched groups with and without CKD. Infection and revision rates seem to be similar. We advocate for a shared decision-making approach between patient and surgeon to include a thorough discussion weighing postoperative complication risk, patient function, and life expectancy. LEVEL OF EVIDENCE/METHODS:III.

BACKGROUND:This study evaluated differences in surgical and clinical outcomes among patients who have identical versus different implant sizes in sequential total knee arthroplasty (TKA) surgeries. METHODS:We retrospectively reviewed patients who underwent primary, elective, staged, bilateral, same-surgeon, same-prosthesis TKA between 2011 and 2024 at a large academic health system. Patients were grouped by femoral and tibial implant size consistency: same femoral and tibial (SS), different femoral, same tibial, different tibial, same femoral, and different femoral and tibial (DD). RESULTS:A total of 4,536 TKAs were performed in 2,268 patients. The SS had the shortest length of stay compared to DD (51.8 versus 58.2 hours, P < 0.001). The majority had the same femoral (75.6%) and tibial (76.6%) sizes in both knees, whereas polyethylene thickness varied. Undergoing contralateral surgery within one year was associated with receiving the same implant sizes (P < 0.001). The DD were more common in manual surgery, and the SS were more common using navigation assistance (P < 0.001). Different assistance modalities between surgeries increased different femoral, same tibial and DD, whereas the same navigation assistance increased SS (P < 0.001). Complication and revision rates were not significantly different between the groups. All groups showed improvement in their Knee injury and Osteoarthritis Outcome Score for Joint Replacement and Patient-Reported Outcomes Measurement Information System Pain Intensity and Interference scores with no significant intergroup differences (P > 0.05). CONCLUSIONS:Over one-third of patients (37.3%) undergoing staged, bilateral TKA received different implant sizes for at least one component, and over half had different polyethylene thicknesses. Although implant size consistency was influenced by factors such as time between surgeries and assistance modality, these variations did not significantly affect length of stay, complications, or patient-reported outcomes. Surgeons should be aware that minor implant size differences between knees are common, even when using the same prosthesis.

BACKGROUND:Robotic-assisted total joint arthroplasty (RTJA) is increasingly used to improve patient outcomes and reduce revision rates in total joint arthroplasty (TJA). With robotic-assisted total knee arthroplasty (RTKA) projected to exceed 70% of cases by 2030, concern exists about whether orthopaedic residents are being adequately trained. METHODS:Orthopaedic arthroplasty fellows between 2023 and 2025 completed an anonymous electronic survey assessing exposure to RTJA and conventional TJA (CTJA), impact on fellowship selection, and projected future use. Incomplete responses and non-fellows were excluded. RESULTS:Of 60 respondents, 78% were exposed to RTKA, 52% to robotic-assisted unicompartmental knee arthroplasty (RUKA), and 48% to robotic-assisted total hip arthroplasty (RTHA). Satisfaction with training was higher for conventional procedures: 82 versus 53% (TKA), 97 versus 32% (THA), and 23 versus 31% (UKA). Most felt comfortable performing conventional TKA (CTKA) and THA (CTHA) independently; among robotic procedures, only RTKA had similar comfort levels. Fellowship selection was influenced by a desire for balanced robotic and manual experience (66.7%). While 42% did not believe robotics should be required in residency, most agreed it improved understanding and performance (68% RTKA, 61% RUKA, and 75% RTHA respondents). Robotic exposure during residency was associated with higher satisfaction and preparedness (P < 0.001) and increased support for requiring training in RUKA (P = 0.015) and RTHA (P = 0.006). Regional differences in exposure and satisfaction were also observed. Fellows planning to use robotics in greater than 50% of future cases were more likely to choose robotics-focused fellowships (P = 0.003). CONCLUSION/CONCLUSIONS:Arthroplasty fellows reported high satisfaction with conventional arthroplasty training, whereas satisfaction and self-reported preparedness for robotic-assisted procedures were lower. Prior robotic exposure during residency was associated with higher satisfaction and preparedness, and fellows expressed interest in balanced robotic and manual fellowship experiences. These findings provided a baseline of current trainee perceptions.

BACKGROUND:Simultaneous bilateral total knee arthroplasty (BTKA) is avoided due to higher perioperative risk, favoring staged procedures. This study evaluated how the interval between staged TKAs affects patient-reported outcome measures (PROMs) and compared complications between the first and second procedures. METHODS:We retrospectively reviewed patients undergoing primary, elective, staged, BTKAs at a high-volume academic center between 2011 and 2024. Intra- and perioperative data and complications were compared between the surgeries. Patients were stratified by interval: less than three months ("extremely short waiters"), three to six months, six to nine months, nine to 12 months, one to two years, two to five years, and greater than five years. The PROMs were compared across these groups. A total of 4,210 patients underwent 8,420 staged, BTKAs at a mean 21.4-month interval. The most common intervals were six to nine months (27.4%) and nine to 12 months (21.1%). RESULTS:Patients were more likely to return to the emergency department (22 versus 16, P = 0.030) and be readmitted (48 versus 26, P = 0.113) after the second surgery, primarily due to infection. Revision rates did not differ. "Extremely short waiters" had the greatest improvement in Patient-Reported Outcomes Measurements Information System Pain Intensity and interference scores nine months after the second TKA (change 13.4 and 15.1, P < 0.001). At three months following the second surgery, those who waited three to six months had the largest Knee Injury and Osteoarthritis Outcome Score for Joint Replacement score improvement (change 23.7, P = 0.004). At one year after the second surgery, "extremely short waiters" again showed the greatest reduction in Patient-Reported Outcomes Measurements Information System Pain Intensity (change 10.5, P = 0.007) and Interference (change 11.3, P < 0.001). CONCLUSIONS:The interval between surgeries significantly impacted PROMs, with shorter intervals associated with better pain relief and functional recovery. Surgical timing should be tailored to individual patient goals and recovery trajectories.