Faculty Bibliography

BACKGROUND:It is unclear howmetal augments,polyethylene (PE) liner thickness, and length of cemented stemcontribute to load transferwhen reconstructing uncontained tibial metaphyseal bone loss of Anderson Orthopedic Research Institute (AORI) Type II defects during revision total knee arthroplasty (rTKA).The aimof this study is to understand the impact of these three variableson load transfer through the tibial baseplate. For a fixed defect depth, we hypothesized that there is a particular combination of liner and augment thickness and stem length that minimizes bone stress, reducing the risk of aseptic loosening. METHODS:We conducted a finite element analysis (FEA) to model stresses at the bone-cement interface with different iterations of metal augments, PE liner thicknesses andfully-cemented stems lengths. RESULTS:For a 20 mm tibial defect, constructs with thicker metal augments and thinner polyethylene liners were superior. Constructswith a fully cemented stem further reduced bone stress on the tibial plateau. Bone stress was lowest when a 100 mm fully-cemented stem was used, while stems between 30 mm - 80 mm produced similar results. CONCLUSIONS:When addressing a tibial bone defect of AORI Type II in rTKA, our FEA model demonstrates that surgeons should opt to use the thickest metal augments in combination with afully-cemented stem with an added length of at least 30 mm, which allows for surgical flexibility together with the most stable construct.Our study is notably limited by lack of modeling of knee joint moments, which are important when considering micromotion, bone-implant interface and stem effectiveness.

INTRODUCTION/UNASSIGNED:The purpose is to investigate the incidence of wound complications for total knee arthroplasty (TKA) following tibial plateau open reduction and internal fixation (ORIF). MATERIALS AND METHODS/UNASSIGNED:A prospective arthroplasty registry was queried for patients with CPT codes for primary TKA, tibial plateau ORIF, removal of hardware (ROH), and diagnosis of post-traumatic arthritis. Patients were included if they had undergone tibial plateau ORIF and subsequent TKA. Chart review was performed to obtain demographic, clinical and post-operative information. RESULTS/UNASSIGNED:Twenty-one patients were identified, with average age of 56.23 ± 13.2 years at time of tibial plateau ORIF and 62.91 ± 10.8 years at time of TKA. Seven (33.3%) patients had a tibial plateau fracture-related infection (FRI). Eight (38.1%) patients underwent ROH prior to TKA. Seven (33.3%) patients' TKA incision incorporated the prior plateau incisions. Eight (36.4%) patients developed wound complications following TKA and 5 (23.8%) developed an acute periprosthetic joint infection (PJI) following TKA and had the plateau incision incorporated into the TKA incision. FRI history did not increase the rate of wound complications but did increase the rate of ROH prior to TKA. CONCLUSIONS/UNASSIGNED:Previous FRI involving tibial plateau repair surgery doesn't correlate with PJI after conversion TKA for post traumatic OA. Surgeon-controlled factors such as staged ROH and incision placement can help reduce the rate of wound complications following TKA performed after tibial plateau ORIF. LEVEL OF EVIDENCE/UNASSIGNED:Prognostic Level IV. SUPPLEMENTARY INFORMATION/UNASSIGNED:The online version contains supplementary material available at 10.1007/s43465-022-00709-1.

INTRODUCTION/BACKGROUND:A novel fully porous acetabular titanium shell has been designed to reduce stiffness mismatch between bone and implant and promote osseointegration in complex (cTHA) and revision total hip arthroplasty (rTHA). A highly cross-linked polyethylene (XLPE) liner is cemented within the cup to reduce wear rates and increase survivorship. This study reported the outcomes of an XLPE liner cemented into a novel 3D-printed fully porous cup in cTHA and rTHA. METHODS:Presented was a multicenter retrospective review of 40 patients (6 cTHA and 34 rTHA) who underwent THA with a fully porous titanium acetabular cup and cemented XLPE liner. Data were collected on demographics, surgical information, outcomes, including osseointegration and migration and implant survivorship. RESULTS:) and were followed up for a mean time of 2.21 ± 0.77 years. Six patients underwent cTHA and 34 patients underwent rTHA. The mean hospital length of stay was 5.34 ± 3.34 days. Three (7.5%) 90-day readmissions were noted. Harris Hip Scores improved, on average, from 53.87 ± 12.58 preoperatively to 83.53 ± 12.15 postoperatively (P<0.001). One case of acetabular shell aspetic loosening with migration was noted. Thirty-nine of the 40 acetabular components were fully osseointegrated without migration. Two patients underwent re-revision surgery for PJI and one patient received acetabular shell+liner re-revision due to aseptic loosening. Kaplan-Meier analysis showed an all-cause revision-free survival rate of 95.0% at 6 months and 1 year, and 92.0% at 4-years. Aseptic acetabular cup, liner dislocation/loosening, and fracture-free survival was 100% at 6 months and 1-year, and 97.1% at 2 years. CONCLUSION/CONCLUSIONS:The combined use of a novel 3D-printed fully porous titanium acetabular shell and cemented XLPE acetabular liner yielded excellent rates of osseointegration, and all-cause and acetabular aseptic loosening survivorship at a minimum 1-year follow-up. Further long-term studies are needed to assess the longevity of this construct.

INTRODUCTION/BACKGROUND:Spinal anesthesia (SA) is the preferred method of anesthesia at many centers for total joint arthro- plasty (TJA). However, a small subset of patients fails SA, necessitating a conversion to general anesthesia (GA). This report assesses the patient characteristics associated with failed SA. METHODS:A retrospective study was conducted on patients who underwent SA during their primary TJA between Janu- ary 2015 and December 2016 at our institution. A subset of this group required a conversion from SA to GA. Anesthesia reports were reviewed for the number of attempts at SA and the documented reason for failure. The SA failure cohort was then subdivided into failure categories based on the reasons that had been provided. RESULTS:A total of 5,706 patients were included in this study, 78 of which experienced SA failure. The number of attempts was most strongly associated with SA failure, with three attempts resulting in a five times increased failure rate (OR = 4.73, p = 0.010) and four attempts resulting in 12 times increased failure rate compared to the no failure cohort (OR = 12.3, p < 0.001). Greater than two attempts occurred in 87.5% of the "technical failure" sub-group of the SA failure cohort (p < 0.001). No difference was demon- strated among the other patient characteristics, such as age, sex, body mass index, race, American Society of Anesthesia (ASA) score, and surgical time. CONCLUSIONS:The results suggest that the major predic- tor influencing spinal to general anesthesia conversion was the number of attempts at SA, especially among technical failure cases. Based on the results, it may be appropriate for anesthesiologists to convert to GA after two failed spi- nal attempts. Further studies are warranted to assess this relationship for firm clinical recommendations.

Introduction/UNASSIGNED:The use of tourniquets and bipolar sealers are effective methods of hemostasis during total knee arthroplasty (TKA). However, their effect on perioperative patient outcomes is unknown. The purpose of this study is to compare the efficacy of tourniquet-less, tourniquet-less with use of a bipolar sealer, and tourniquet use on postoperative pain and surgical outcomes following TKA. Methods/UNASSIGNED: = 40). Results/UNASSIGNED: = 0.025). Conclusion/UNASSIGNED:Our findings demonstrate that both bipolar sealer and tourniquet use in TKA are associated with similar postoperative pain levels and LOS in comparison to tourniquet-less only TKA. However, bipolar sealer and tourniquet use may lead to better longer term improvement such as greater PRO score improvement and fewer readmissions.

Background/UNASSIGNED:Fully porous acetabular shells are an appealing choice for patients with extensive acetabular defects undergoing revision total hip arthroplasty (rTHA). This study reports on the early outcomes of a novel 3-D printed fully porous titanium acetabular shell in revision acetabular reconstruction. Methods/UNASSIGNED:A multicenter retrospective study of patients who received a fully porous titanium acetabular shell for rTHA with a minimum of 2 years of follow-up was conducted. The primary outcome was rate of acetabular revision. Results/UNASSIGNED:(standard deviation 5.9). Ninety-four percent had a preoperative Paprosky defect grade of 2A or higher. The average follow-up duration was 3.0 years (range 2.0-5.1). Revision-free survivorship at 2 years was 81% for all causes, 88% for acetabular revisions, and 90% for acetabular revision for aseptic acetabular shell failure. Eight shells were explanted within 2 years (12%): 3 for failure of osseointegration/aseptic loosening (4%) after 15, 17, and 20 months; 3 for infection (4%) after 1, 3, and 6 months; and 2 for instability (3%). At the latest postoperative follow-up, all unrevised shells showed radiographic signs of osseointegration, and none had migrated. Conclusions/UNASSIGNED:This novel 3-D printed fully porous titanium shell in rTHA demonstrated good survivorship and osseointegration when used in complex acetabular reconstruction at a minimum of 2 years. Level of evidence/UNASSIGNED:IV, case series.

Obesity, defined as a body mass index (BMI) >30, is associated with an increased likelihood of osteoarthritis and need for total joint arthroplasty (TJA). Unfortunately, the morbidly obese population has a higher risk of postoperative complications. For some surgeons, patient selection criteria for TJA includes BMI<40. The associated risks are recognized by The American Association of Hip And Knee Surgeons, and many surgeons follow these guidelines. Importantly, as obese patients have been demonstrated to have equal or greater gains in functional outcomes and quality of life metrics, it is important for obese patients to have access to TJA. Through a comprehensive literature review and structured interviews with leading surgeons in the field, we provide guidance for orthopedic surgeons treating patients with BMI>40 to minimize risks, including tailored preoperative, intraoperative, and postoperative considerations.

BACKGROUND:The prevalence of obesity in total hip arthroplasty (THA) patients has been studied in the past. However, there has not been direct comparison against obesity in the general population. This study compared yearly trends in BMI and obesity rates between patients who had undergone primary THA and those from the general patient population. METHODS:We retrospectively reviewed all patients over the age of 18 who underwent primary, elective THA and those who had an annual routine physical exam between January 2013 and December 2020 at our academic tertiary medical center. Baseline demographics were controlled in our statistical models. Significance of yearly trends was determined through a linear regression analysis. Independent samples t-test and Chi-square test were used to compare means and proportions between the two groups, respectively. RESULTS:A total of 11,250 primary THA patients and 1,039,918 annual physical exam patients were included. Average BMI for the THA group was significantly higher (P < 0.001) each year compared to the annual physicals group (APG). Higher obesity rates were observed in all obesity subgroups (all classes, and class I-III individually) for THA patients each year compared to the APG. Interestingly, while we found a significantly increasing trend in obesity for the general population (P < 0.001), BMI and obesity rates remained stable in the THA population. CONCLUSION/CONCLUSIONS:While our general patient population showed significant increase in BMI and obesity over time, THA patients had higher, yet stable, BMI. Further investigation is required to determine the role of risk optimization in these findings. LEVEL III EVIDENCE/METHODS:Retrospective Cohort Study.