Faculty Bibliography

The management of acetabular bone loss during revision arthroplasty is a challenging problem. Not only are there a wide variety of potential defects, but the location of these defects can also drastically change the hip center of rotation, stability, and biomechanics. First, the assessment of the severity and location of bone loss preoperatively is highlighted as it is imperative to evaluate the acetabular bone stock remaining. It is especially important to determine how to identify a pelvic discontinuity. Various classification systems are discussed to help surgeons adequately assess and evaluate these defects. There are also numerous implants and treatment strategies available to manage the problem, all of which are determined by that preoperative assessment and classification. We review the history of managing these defects and how management has evolved into modern designs, including but not limited to structural allograft, distraction arthroplasty, jumbo cups, metal augments, cup-cages, and custom triflanges. This review then describes the up-to-date clinical results of these various techniques, highlighting the surgical execution needed to obtain a successful result. By describing the preoperative assessment, the acetabular defect classifications, and proposed evidence-based treatment algorithms, we hope that this review will enhance the understanding of these challenging reconstructions in the setting of acetabular bone defects.

Total joint arthroplasty relies on the use of biomaterials that are biologically inert and capable of forming wear-resistant articulating surfaces. Polyethylene use in arthroplasty has become ubiquitous since its introduction in the 1960s. Early arthroplasty procedures of the hip utilized poly-tetra-flouroethylene, or "Teflon," due to its low coefficient of friction that was presumed to closely mimic the hyaline cartilage of native joints. Early catastrophic wear of Teflon caused a significant local tissue reaction contributing to osteolysis, aseptic loosening, and clinical failure ultimately limiting the material's surgical utility. Advancements in biomaterial synthesis and processing led to the fortuitous discovery of ultra-high-molecular-weight-polyethylene (UHMWPE) and the eventual evolution to highly cross-linked polyethylene (HXLPE) as a bearing surface in hip arthroplasties with robust, long-term clinical success. Ultra-high-molecularweight-polyethylene was readily adopted for use in total knee arthroplasty following the material's successful use in hip replacement, however, the unique biomechanics of the knee have posed unique challenges. The use of HXLPE in knee arthroplasty has increased, however, clear data regarding its benefit over UHMWPE are conflicting. Recently, clinical as well as research and development studies of UHMWPE and HXLPE have focused on alternative postprocessing methods to optimize material stability and wear resistance. Second generation HXLPE utilizing sequential annealing processes or vitamin E to stabilize free radicals are promising means to improve mechanical stability and wear resistance for use in joint arthroplasty, however, more data is required to evaluate long-term outcomes and cost-effectiveness. In this review, we discuss the history and innovation of polyethylene use in orthopedic surgery and evaluate the current literature on outcomes of polyethylene use in hip and knee replacement.

BACKGROUND:Indications for surgery may impact resource utilization in aseptic revision total knee arthroplasty (rTKA), and understanding these relationships would facilitate risk-stratification preoperatively. The purpose of this study was to investigate the impact of rTKA indications on readmission, reoperation, length of stay (LOS), and cost. METHODS:We reviewed all 962 patients who underwent aseptic rTKA at an academic orthopedic specialty hospital between June 2011-April 2020 with at least 90 days of follow-up. Patients were categorized based on their indication for aseptic rTKA as listed in the operative report. Demographics, surgical factors, LOS, readmission, reoperation and cost were compared between cohorts. RESULTS:There were significant differences in operative time among cohorts (p < 0.001), highest among the periprosthetic fracture group (164.2 ± 59.8 min). Reoperation rate was greatest in the extensor mechanism disruption cohort (50.0 %, p = 0.009). Total cost differed significantly among groups (p < 0.001), which was highest among the implant failure cohort (134.6 % of mean) and lowest for component malpositioning cohort (90.2 % of mean). Similarly, there were significant differences in direct cost (p < 0.001) which was highest in the periprosthetic fracture cohort (138.5 % of mean), and lowest in the implant failure cohort (90.5 % of mean). There were no differences in discharge disposition, or number of re-revisions among all groups. CONCLUSIONS:Operative time, components revised, LOS, readmissions, reoperation rate, total cost and direct cost following aseptic rTKA varied significantly between different revision indications. These differences should be noted for preoperative planning, resource allocation, scheduling, and risk-stratification. LEVEL OF EVIDENCE/METHODS:III, retrospective observational analysis.

INTRODUCTION/BACKGROUND:The purpose of this study is to investigate whether the specific socioeconomic factor such as marital status has any effect on clinical outcomes and patient-reported outcome measures (PROMs) after primary total hip (THA) and knee (TKA) arthroplasty. MATERIALS AND METHODS/METHODS:We retrospectively reviewed patients who underwent primary THA or TKA from January 2019 to August 2019 who answered all PROM questionnaires. Both THA and TKA patients were separated into two groups based on their marital status at the time of surgery (married vs. non-married). Demographics, clinical data, and PROMs (FJS-12, HOOS, JR, KOOS, JR, and VR-12 PCS&MCS) were collected at various time-periods. Demographic differences were assessed using chi-square and independent sample t tests. Clinical data and mean PROMs were compared using multilinear regressions while accounting for demographic differences. RESULTS:This study included 389 patients who underwent primary THA and 193 that underwent primary TKA. In the THA cohort, 256 (66%) patients were married and 133 (34%) were non-married. In the TKA cohort, there were 117 (61%) married patients and 76 (39%) non-married patients. Length of stay was significantly shorter for married patients in both the THA (1.30 vs. 1.64; p = 0.002) and TKA (1.89 vs. 2.36; p = 0.024) cohorts. Surgical-time, all-cause emergency department visits, discharge disposition, and 90-day all-cause adverse events (readmissions/revisions) did not statistically differ between both cohorts. Both HOOS, JR and KOOS, JR score improvements from baseline to 1-year did not statistically differ for the THA and TKA cohorts, respectively. Although VR-12 PCS (p = 0.012) and MCS (p = 0.004) score improvement from baseline to 1-year statistically differed for the THA cohort, they did not for the TKA cohort. CONCLUSION/CONCLUSIONS:Total joint arthroplasty may yield similar clinical benefits in all patients irrespective of their marital status. Although some PROMs statistically differed among married and non-married patients, the differences are likely not clinically significant. Surgeons should continue to assess levels of psychosocial support in their patients prior to undergoing TJA to optimize outcomes. LEVEL OF EVIDENCE/METHODS:III, Retrospective Cohort Study.

INTRODUCTION/BACKGROUND:The purpose of this study is to report on the association between the number of stairs to enter home and length of stay (LOS), discharge disposition, and patient reported outcome measures (PROMs) among patients who underwent primary total joint arthroplasty (TJA). MATERIALS AND METHODS/METHODS:We retrospectively reviewed patients who underwent primary total hip or knee arthroplasty between January 2016 and March 2020. Only patients with documentation of the number of stairs to enter their homes were included in the study. The two cohorts were separated into four groups: none, 1-10, 11-20, and > 20 stairs. Collected variables included demographic data, LOS, discharge disposition, and PROMs. Chi-square and ANOVA were utilized to determine significance. RESULTS:Of the 1116 patients included, 510 underwent THA, and 606 underwent TKA. There was no statistical difference in LOS (THA: p = 0.308; TKA: p = 0.701) and discharge disposition (THA: p = 0.371; TKA: p = 0.484) in both cohorts regardless the number of stairs. There was no statistical difference in FJS-12 scores at 3 months (THA: p = 0.590; TKA: p = 0.206), 12 months (THA: p = 0.217; TKA: p = 0.845), and 21 months (THA: p = 0.782; TKA: p = 0.296) postoperatively for both cohorts. There was no statistical difference in HOOS, JR scores preoperatively (p = 0.278) and at 3 months postoperatively (p = 0.527) for the THA cohort, as well as KOOS, JR scores preoperatively and at 3 and 12 months postoperatively (p = 0.557; p = 0.522; p = 0.747) for the TKA cohort. CONCLUSION/CONCLUSIONS:We found no statistical differences in LOS, discharge disposition, and PROMs in patients who underwent TJA, irrespective of the number of stairs negotiated to enter their home. These findings can aid surgeons to provide preoperative education and reassurance to patients who have concerns with their discharge planning due to the walk-up stairway at their residence.

INTRODUCTION/BACKGROUND:Although tourniquet use in primary total knee arthroplasty (TKA) has been widely studied, the outcomes associated with tourniquet use in revision TKA (rTKA) remains relatively unexplored. This study investigates surgical outcomes and patient satisfaction in association with tourniquet use during aseptic rTKA. METHODS:We retrospectively reviewed all patients who underwent rTKA for aseptic causes at our institution from 2011-2020. Patients were separated into two cohorts based on tourniquet inflation during the procedure. Outcomes of interest included estimated blood loss (EBL), change in hemoglobin (Hb), surgical time, length-of-stay (LOS), reoperation rate, and Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS,JR) scores. RESULTS:Of the 1,212 patients included, 1,007 (83%) underwent aseptic rTKA with the use of a tourniquet and 205 (17%) without the use of a tourniquet. The mean tourniquet inflation time was 93.0 minutes (SD:33.3 minutes). Blood loss was significantly less for patients in the tourniquet cohort as measured through EBL(224.1vs.325.1 mL,p<0.001) and change in preoperative to postoperative Hb(1.75vs.2.04 g/dL,p<0.001). There were no statistical differences in surgical time(p=0.267) and LOS(p=0.206) between the two groups. The reoperation rate was significantly greater for patients who did not have a tourniquet utilized (20.5%vs.15.0%,p=0.038). Delta improvement in KOOS,JR scores from baseline to 3-months postoperatively did not statistically differ between the two cohorts (p=0.560). CONCLUSION/CONCLUSIONS:While delta improvements in KOOS,JR scores were similar for both cohorts, patients who did not have a tourniquet inflated during aseptic rTKA had increased blood loss and were more likely to undergo subsequent reoperation compared to patients who did.

INTRODUCTION/BACKGROUND:Medicaid expansion has allowed more patients to undergo total hip arthroplasty (THA). Given the continued focus on the opioid epidemic, we sought to determine whether patients with Medicaid insurance differed in their postoperative pain and narcotic requirements compared with privately or Medicare-insured patients. METHODS:A single-institution database was used to identify adult patients who underwent elective THA between 2016 and 2019. Patients in the Medicaid group received Medicaid insurance, while the non-Medicaid group was insured commercially or through Medicare. Subgroup analysis was done, separating the private pay from Medicare patients. RESULTS:A total of 5,845 cases were identified: 326 Medicaid (5.6%) and 5,519 non-Medicaid (94.4%). Two thousand six hundred thirty-five of the non-Medicaid group were insured by private payors. Medicaid patients were younger (56.1 versus 63.28 versus 57.4 years; P < 0.001, P < 0.05), less likely to be White (39.1% versus 78.2% versus 76.2%; P < 0.001), and more likely to be active smokers (21.6% versus 8.8% versus 10.5%; P < 0.001). Surgical time (113 versus 96 versus 98 mins; P < 0.001) and length of stay (2.7 versus 1.7 versus 1.4 days; P < 0.001) were longer for Medicaid patients, with lower home discharge (86.5% versus 91.8% versus 97.2%; P < 0.001). Total opioid consumption (178 morphine milligram equivalents [MMEs] versus 89 MME versus 82 MME; P < 0.001) and average MME/day in the first 24 hours and 24 to 48 hours (52.3 versus 44.7 versus 44.45; P < 0.001 and 73.8 versus 28.4 versus 29.8; P < 0.001) were higher for Medicaid patients. This paralleled higher pain scores (2.71 versus 2.31 versus 2.38; P < 0.001) and lower Activity Measure for Post-Acute Care scores (18.77 versus 20.98 versus 21.61; P < 0.001). CONCLUSIONS:Medicaid patients presenting for THA demonstrated worse postoperative pain and required more opioids than their non-Medicaid counterparts. This highlights the need for preoperative counseling and optimization in this at-risk population. These patients may benefit from multidisciplinary intervention to ensure that pain is controlled while mitigating the risk of continuation to long-term opioid use.

BACKGROUND:There are a variety of methods available to treat periprosthetic joint infection (PJI), including 2-stage revision with the use of an antibiotic spacer. This study compares the outcomes of real-component (RC) and all-cement (AC) articulating spacers for total hip arthroplasty (THA) PJI treatment. METHODS:This multicenter retrospective study assessed all articulating spacers placed for THA PJI between April 2011 and August 2020. Patients were dichotomized based on spacer type (RC vs AC). RESULTS:One hundred four patients received articulating spacer constructs (RC group = 75, AC group = 29). Leg-length discrepancy was significantly greater in the AC group after the second stage (3.58 vs 12.00 mm, P = .023). There were no significant differences in reoperation rates following first-stage spacer placement (P = .752) and time to reimplantation (P = .127) between the groups. There were no significant differences in reinfection rates (RC group = 10.0%, AC group = 7.1%, P = 1.000) and reoperation rates following second-stage revision THA (RC group = 11.7%, AC group = 10.7%, P = 1.000). Hospital length of stay (in days) had a trend toward being shorter following the first (7.35 vs 11.96, P = .166) and second stage (3.95 vs 5.43, P = .107) for patients in the RC group. Patients in the RC group were more likely to be discharged home following the first (P = .020) and second (P = .039) stages. CONCLUSION/CONCLUSIONS:Given that there were no differences in reinfection and reoperation rates between the 2 spacer constructs, RC articulating spacers may provide a significant benefit for patient comfort during 2-stage exchange treatment of PJI while adding no increase in risk profile.

BACKGROUND:Although several techniques and implants have been developed to address bone loss in revision total knee arthroplasty (rTKA), management of these defects remains challenging. This review article discusses the indications and management options of bone loss following total knee arthroplasty based on preoperative workup and intraoperative findings. MAIN TEXT/METHODS:Various imaging modalities are available that can be augmented with intraoperative examination to provide a clear classification of a bony defect. For this reason, the Anderson Orthopaedic Research Institute (AORI) classification is frequently used to guide treatment. The AORI provides a reliable system by which surgeons can classify lesions based on their size and involvement of surrounding structures. AORI type I defects are managed with cement with or without screws as well as impaction bone grafting. For AORI type IIA lesions, wedge or block augmentation is available. For large defects encompassing AORI type IIB and type III defects, bulk allografts, cones, sleeves, and megaprostheses can be used in conjunction with intramedullary stems. CONCLUSIONS:Treatment of bone loss in rTKA continues to evolve as different techniques and approaches have been validated through short- and mid-term follow-up. Extensive preoperative planning with imaging, accurate intraoperative evaluation of the bone loss, and comprehensive understanding of all the implant options available for the bone loss are paramount to success.