Faculty Bibliography

INTRODUCTION/BACKGROUND:Intraprosthetic dislocation (IPD) is a rare but potentially catastrophic complication of dual-mobility (DM) implants, defined by dissociation of the inner femoral head from the polyethylene liner. Modular dual-mobility (MDM) designs were introduced to improve intraoperative flexibility and expand indications for DM technology. However, increasing reports of IPD have raised concerns that implant design and manufacturing differences may influence risk. The true incidence of IPD across MDM manufacturers remains unclear. METHODS:A systematic search of PubMed, Embase, and Web of Science was performed. Studies reporting IPD incidence and stratified outcomes by implant manufacturer were included. A random-effects proportion meta-analysis was conducted to estimate pooled IPD incidence and revision rates overall and by manufacturer. RESULTS:Of 523 identified articles, 32 met inclusion criteria, representing 3996 implants (2711 primary; 1285 revision). Mean follow-up was 3.48 years and mean age was 67.48 years. The overall IPD incidence was 0.38% (15/3996), with a pooled estimate of 0.1% (95% CI, 0-0.5%). Stratified analyses showed IPD rates of 0% for Stryker (95% CI, 0-0.7%), 0% for Zimmer (95% CI, 0-100%), and 0% for Groupe Lépine (95% CI, 0-100%). Reoperation rates were 1.4% (95% CI, 0.9-2.1%) in primary and 8.3% (95% CI, 6.0-11.3%) in revision THA. CONCLUSIONS:The incidence of IPD in MDM implants is low, with pooled rates remaining below 1%. Revision rates were modest and consistent with published data on complex hip arthroplasty. No significant differences between manufacturers were detected, though findings are limited by the small number of non-Stryker implants reported. These findings suggest that MDM designs appear safe with overall low numbers of IPD-related complications, however, larger registry-based studies are needed to better define potential design-related differences in IPD risk.

INTRODUCTION/BACKGROUND:Obtaining adequate informed consent is a fundamental component of surgical care, often conducted by trainees at academic medical centers. However, the quality of trainees' informed consent remains unclear. To guide future instruction, this study assessed trainees' confidence and performance with the informed consent process, stratified by postgraduate year and previous consent education. METHODS:An objective structured clinical examination (OSCE) was developed to assess informed consent discussions between housestaff trainees and standardized patients undergoing primary total knee arthroplasty. A total of 18 orthopaedic residents (six each in postgraduate years [PGYs] 1, 3, and 5) and five clinical fellows in adult reconstruction (PGY-6) participated. Quality of informed consent was assessed with an objective rubric, scored 0 to 2 ("not addressed," "attempted," and "completed"). Trainees completed a post-OSCE survey assessing their confidence and previous training in obtaining informed consent. RESULTS:All 23 trainees considered informed consent "extremely important," and 96% thought that formal training would be "very" or "extremely beneficial." Yet, only 30% recalled receiving consent education, and 39% had never received clinical feedback on their consent process. Average OSCE performance was 16.2/20 (range: 11-19). Common deficiencies were assessing patient comprehension (13% completed) and facilitating shared decision making (39% completed). Only 35% of trainees identified assessing patient comprehension as critical. Performance did not differ significantly by training level. Previous consent education significantly improved trainees' ability to explain procedures (1.7/2.0 vs. 1.2/2.0; P = 0.013) and was associated with better shared decision-making facilitation (1.4/2.0 vs. 1.0/2.0; P = 0.255), although not statistically significant. CONCLUSION/CONCLUSIONS:Orthopaedic trainees value formal informed consent training but lack structured education and informal feedback. While overall performance was strong, consistent deficiencies in assessing comprehension and shared decision making were noted. Seniority alone did not improve performance, while previous formal education improved procedure explanations. These findings support the implementation of structured informed consent curricula across all levels of orthopaedic training.

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/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.

While there have been great advancements in total knee arthroplasty (TKA) over the past 50 years, anterior knee pain (AKP) remains the most common concern among patients postoperatively. Despite exhausting evidence supporting no clinical difference in AKP with resurfaced vs. unresurfaced patellae in TKA, 87% of TKAs are resurfaced in the United States, compared with 2% in other countries. These large practice variations underscore a lack of consensus regarding the role of the patella and the approach to the anterior compartment of the knee in TKA. The aim of this review was to go beyond patellar resurfacing and describe the effects that surgical technique and implant design may have on AKP in current TKA.

BACKGROUND:Total hip arthroplasty (THA) is commonly performed using either an anterior- or posterior-based approach (AA or PA), with similar long-term outcomes. However, operative timings, including time for patient positioning, device implantation, wound closure, and total operating room (OR) time, may differ between these approaches. This study assessed differences in various OR timings between AA and PA for primary THA. METHODS:A retrospective review was performed of all patients who underwent primary, unilateral, elective THA at our large urban academic medical center between January 1, 2019, and January 31, 2025. Patient demographics and operative parameters were determined from clinical and operative records. Surgeons who began practicing during the study period had their first 50 cases excluded. Perioperative timings were compared between approaches. Multivariable regression analyses controlled for age, American Society of Anesthesiologists status, body mass index, cementation, robotic use, navigation assistance use, discharge disposition, sex, smoking status, and year of surgery. There were 8,120 procedures included (4,670 PA and 3,450 AA). RESULTS:The AA had shorter total OR time (156.7 versus 167.4 minutes, P < 0.001). Regression analysis found AA was associated with longer implantation time (+3.3 minutes, P < 0.001), but shorter set-up time (-2.0 minutes, P < 0.001), closure time (-7.5 minutes, P < 0.001), overall operative time (-4.2 minutes, P < 0.001), and take-down time (-3.6 minutes, P < 0.001). Cement fixation had an increased effect on AA operative times compared to PA (+28.9 versus +14.4 minutes; P < 0.001). CONCLUSIONS:Anterior approach THA procedures displayed faster set-up, closure, take-down, and OR times compared to PA. Controlling for covariates, AA reduces total OR time by nearly 10 minutes, although operative time with AA is more significantly impacted by cementation. Further studies investigating the cost analysis of AA versus PA are needed to contextualize these findings regarding timing.

BACKGROUND:Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) are widely used as screening tools for periprosthetic joint infection (PJI) following total knee and hip arthroplasty (TKA and THA, respectively). However, the significance of an isolated elevated ESR with a normal CRP, especially in cases with low clinical suspicion, remains unclear. METHODS:We retrospectively reviewed 19,872 primary TKAs and 12,143 primary THAs performed between March 2012 and March 2023 at a high-volume academic orthopaedic hospital. Of these, 656 TKA and 253 THA patients ≥ 18 years old who underwent elective TJA for osteoarthritis had an elevated ESR (higher than 30 millimeters/hour) and a normal CRP (less than or equal to 10 milligrams/liter) at least 90 days postoperatively. These cutoffs were chosen in concordance with the International Consensus Meeting (ICM) 2018 diagnostic criteria for PJI. Patients who were already undergoing PJI treatment were excluded, as it was inferred the serum biomarkers were not drawn for screening purposes. The final cohorts consisted of 641 TKA and 252 THA patients. Data collected through manual chart review of clinical progress notes included presenting symptoms, inflammatory markers, and PJI diagnoses. We calculated the incidence of PJI within the cohort of patients who had an isolated, elevated ESR. RESULTS:Of the 641 TKA patients who had an isolated, elevated ESR, seven (1.1%) were subsequently diagnosed with PJI. Of the 252 THA patients who had an isolated, elevated ESR, three (1.2%) were subsequently diagnosed with PJI. Of the seven TKA and three THA patients subsequently diagnosed with PJI, three (0.5%) TKA and two (0.8%) THA patients had clinical findings highly suspicious for PJI, such as a large effusion and severe, sudden-onset swelling. These patients did not represent cases where a surgeon would encounter true uncertainty regarding whether to pursue further workup and testing. This left four TKA (0.5%) and one THA (0.4%) patient who had an isolated, elevated ESR who were eventually diagnosed with PJI despite limited clinical concern beyond nonspecific pain. The positive predictive value (PPV) of an isolated, elevated ESR for the diagnosis of PJI was 1.1% in the TKA cohort and 1.2% in the THA cohort. CONCLUSION/CONCLUSIONS:Isolated, elevated ESR with a normal CRP should not automatically trigger a full PJI workup. The risk of PJI is low in this specific patient population, especially when only accompanied by nonspecific symptoms. Most PJI cases in this cohort were found in patients who also had relevant clinical symptoms like sudden-onset swelling or large effusions, suggesting that important weight should be given to the presence or absence of additional PJI symptoms when deciding whether to pursue further testing after an isolated, elevated ESR.

BACKGROUND:Vancouver B2 and B3 periprosthetic femur fractures (PPFF) have posed significant treatment challenges due to stem instability and lack of adequate femoral bone stock. This study investigated subsidence, survivorship, and outcomes of Vancouver B2 and B3 fractures, based on the order in which revision stem placement and fracture reduction occurred during revision total hip arthroplasty (rTHA). METHODS:This retrospective, cohort study included 46 rTHAs between June 2011 and April 2023. Included patients underwent rTHA for Vancouver B2 or B3 PPFF with minimum one-year radiographic and two-year clinical follow-up. All patients were treated with diaphyseal-engaging tapered fluted titanium stems and stem modularity decisions were based on surgeon preference. Cohorts were separated based on if stem placement (SF, n = 19), or fracture reduction (RF, n = 27) occurred first. Patient demographics, intraoperative information, and clinical and radiographic outcomes were collected. RESULTS:The SF and RF cohort showed no statistically significant differences in rate of subsidence ≥5 mm [26.3%[SF], 22.2%[RF], P = 0.749), rate of subsidence ≥ 10 mm (15.8%[SF], 14.8%[RF], P = 0.928), nor average subsidence (4.1 mm[SF], 4.4 mm[RF], P = 0.861). We found no statistically significant differences in surgery-related clinical outcomes or all-cause revision rates within a two-year follow-up period. The groups demonstrated comparable rates of procedure-related 90-day emergency department visits(P = 0.370) and readmissions(P = 0.712). The SF group underwent four revisions for three PJIs and one acetabular component aseptic loosening. The RF cohort underwent four revisions for one acetabular component aseptic loosening, one dislocation, one PPFF, and one PJI. Rates of all-cause revision were comparable(P = 0.583). There was one case within the RF cohort to explant the trochanteric plate with no revision of arthroplasty components. CONCLUSIONS:The present analysis suggests the order in which intraoperative femoral stem implantation and fracture reduction occurs does not affect short-term clinical and radiographic outcomes. This intraoperative decision should be based upon patient anatomy, fracture patterns, and surgeon discretion.

BACKGROUND:Solid organ transplant (SOT) patients undergoing total joint arthroplasty (TJA) may be at higher risk for complications due to complex medical and surgical histories, chronic immunosuppressive medications, and significant ongoing comorbidities. This study aimed to evaluate postoperative outcomes following primary, elective TJA in patients with a history of SOT. METHODS:We retrospectively reviewed 53,043 primary, elective TJA patients from 2011 to 2025. Patients were screened for SOT history prior to TJA. All SOT patients were taking some form of immunosuppressive medication following their transplantation. Demographics, SOT details, and surgical data were obtained. SOT patients (n = 70) underwent a nearest-neighbor 1:3 propensity-score matching to non-SOT (NSOT) controls (n = 210) based on age, sex, smoking, Charlson Comorbidity Index, body-mass index, and TJA indication. Kidney transplants were most common (61.4%), followed by liver (24.3%), and heart (8.6%). Differences in surgical outcomes and postoperative complications between the patients were investigated using Chi-squared tests, independent t-tests and effect size (ES) estimates. Baseline characteristics did not differ between the groups (P > 0.05). RESULTS:SOT patients had significantly longer hospital stays (92 vs. 51 h, P < 0.001, ES = 0.82), higher rates of discharge to skilled nursing facilities (SNF) (15.7% vs. 5.7%, P = 0.014, ES = 0.17) and all-cause 90 day readmissions (15.7% vs. 6.7%, P = 0.040, ES = 0.12), primarily driven by non-surgical reasons (14.3% vs. 4.3%, P = 0.010, ES = 0.16) compared to NSOT patients. All-cause revision rates were comparable between SOT and NSOT patients (4.3% vs. 3.8%, P = 0.999), including aseptic (2.9% vs. 1.9%, P = 0.642) and septic causes (1.4% vs. 1.9%, P = 0.999). CONCLUSIONS:Despite higher rates of SNF discharge and non-surgical 90 day readmissions, SOT patients achieved similar all-cause, septic, and aseptic revision rates, compared to NSOT patients. These findings suggest that compared to well-matched comorbid controls, SOT patients can safely undergo elective TJA with comparable revision risk. Enhanced perioperative care may help reduce readmission risks in this complex population.