Faculty Bibliography

INTRODUCTION/BACKGROUND:The role of advanced imaging in diagnosing aseptic implant loosening following total hip arthroplasty (THA) remains unclear. This study aimed to assess the diagnostic value of magnetic resonance imaging (MRI) in detecting aseptic loosening. METHODS:This was a retrospective review of 342 consecutive patients who underwent revision THA between July 2011 and April 2023 and had a pelvis MRI as part of the preoperative diagnostic evaluation. Among them, 62 patients had an intraoperative diagnosis of aseptic loosening of either the femoral or acetabular component. Patients were stratified based on the concordance between their MRI and radiographs findings. RESULTS:Preoperative MRI showed signs of aseptic loosening in 25/62 patients (sensitivity = 40.3%). Similarly, preoperative radiographs demonstrated signs of aseptic loosening in 27 patients (43.5%). Twelve patients (19.4%) had both MRI and radiographs predictive of aseptic loosening, 22 patients (35.5%) did not show signs of aseptic loosening in either MRI or radiographs, and for 28 patients (45.2%), the results were discordant. Among the patients with a negative radiograph for aseptic loosening (n = 35), 13 patients (37.1%) showed signs of aseptic loosening on MRI. CONCLUSION/CONCLUSIONS:Aseptic loosening remains an elusive diagnosis, and the findings of this study suggest that the utility of MRI and radiographs as part of the diagnostic process is limited. However, in cases of presumed aseptic loosening with inconclusive radiographs findings, MRI may play a role in improving the diagnostic process. LEVEL OF EVIDENCE/METHODS:III.

INTRODUCTION/BACKGROUND:Debridement, antibiotics, and implant retention (DAIR) are the mainstays surgical treatment for acute periprosthetic joint infection (PJI). However, re-operation following DAIR is common, and the risk factors for DAIR failure remain unclear. This study aimed to assess the perioperative characteristics of patients who failed initial DAIR treatment. METHODS:A retrospective review was conducted on 83 patients who underwent DAIR for acute PJI within three months following index surgery from 2011 to 2022, with a minimum one-year follow-up. Surgical outcomes were categorized using the Musculoskeletal Infection Society (MSIS) outcome reporting tool (Tiers 1 to 4). Patient demographics, laboratory data, and perioperative outcomes were compared between patients who had failed (Tiers 3 and 4) (n = 32) and successful (Tiers 1 and 2) (n = 51) DAIR treatment. Logistic regression was also performed. RESULTS:After logistic regression, Charlson Comorbidity Index (CCI) (odds ratio (OR): 1.57; P = 0.003), preoperative C-reactive protein (CRP) (OR: 1.06; P = 0.014), synovial white blood cell (WBC) (OR: 1.14; P = 0.008), and polymorphonuclear cell (PMN%) counts (OR: 1.05; P = 0.015) were independently associated with failed DAIR. Compared with total hip arthroplasty (THA), total knee arthroplasty (TKA) patients (OR: 6.08; P = 0.001) were at increased risk of DAIR failure. The type of organism and time from primary surgery were not correlated with DAIR failure. CONCLUSION/CONCLUSIONS:Patients who had failed initial DAIR tended to have significantly higher CCI, CRP, synovial WBC, and PMN%. The TKA DAIRs were more likely to fail than the THA DAIRs. These characteristics should be considered when planning acute PJI management, as certain patients may be at higher risk for DAIR failure and may benefit from other surgical treatments.

BACKGROUND:Lumbar spinal fusion (LSF) is a risk factor for dislocation following total hip arthroplasty (THA). The effect of the surgical approach on this association has not been investigated. This study examined the association between the surgical approach and dislocation following THA in patients who had prior LSF. METHODS:We retrospectively reviewed 16,223 primary elective THAs at our institution from June 2011 to September 2022. Patients who had LSF prior to THA were identified using International Classification of Diseases (ICD) codes. Patients were stratified by LSF history, surgical approach, and intraoperative robot or navigation use to compare dislocation rates. There were 8,962 (55.2%) posterior, 5,971 (36.8%) anterior, and 1,290 (8.0%) laterally based THAs. Prior LSF was identified in 323 patients (2.0%). Binary logistic regressions were used to assess the association of patient factors with dislocation risk. RESULTS:There were 177 dislocations identified in total (1.1%). In nonadjusted analyses, the dislocation rate was significantly higher following the posterior approach among all patients (P = .003). Prior LSF was associated with a significantly higher dislocation rate in all patients (P < .001) and within the posterior (P < .001), but not the anterior approach (P = .514) subgroups. Multivariate regressions demonstrated anterior (OR [odds ratio] = 0.64, 95% CI [confidence interval] 0.45 to 0.91, P = .013), and laterally based (OR = 0.42, 95% CI 0.18 to 0.96, P = .039) approaches were associated with decreased dislocation risk, whereas prior LSF (OR = 4.28, 95% CI 2.38 to 7.69, P < .001) was associated with increased dislocation risk. Intraoperative technology utilization was not significantly associated with dislocation in the multivariate regressions (OR = 0.72, 95% CI 0.49 to 1.06, P = .095). CONCLUSIONS:The current study confirmed that LSF is a significant risk factor for dislocation following THA; however, anterior and laterally based approaches may mitigate dislocation risk in this population. In multivariate analyses, including surgical approach, LSF, and several perioperative variables, intraoperative technology utilization was not found to be significantly associated with dislocation risk.

BACKGROUND:Current data evaluating the clinical value and cost-effectiveness of advanced diagnostic tests for periprosthetic joint infection (PJI) diagnosis, including alpha-defensin and synovial C-reactive protein (CRP), is conflicting. This study aimed to evaluate the adequacy of preoperative and intraoperative PJI workups without utilizing these tests. METHODS:This retrospective analysis identified all patients who underwent revision total knee or hip arthroplasty (rTKA and rTHA, respectively) for suspected PJI between 2018 and 2020 and had a minimum follow-up of two years. Perioperative data and lab results were collected, and cases were dichotomized based on whether they met the 2018 Musculoskeletal Infection Society (MSIS) criteria for PJI. In total, 204 rTKA and 158 rTHA cases suspected of PJI were reviewed. RESULTS:Nearly 100% of the cases were categorized as "infected" for meeting the 2018 MSIS criteria without utilization of alpha-defensin or synovial CRP (rTKA: n = 193, 94.6%; rTHA: n = 156, 98.7%). Most cases were classified as PJI preoperatively by meeting either the major MSIS or the combinational minor MSIS criteria of traditional lab tests (rTKA: n = 177, 86.8%; rTHA: n = 143, 90.5%). A subset of cases was classified as PJI by meeting combinational preoperative and intraoperative MSIS criteria (rTKA: 16, 7.8%; rTHA: 13, 8.2%). Only 3.6% of all cases were considered "inconclusive" using preoperative and intraoperative data. CONCLUSION/CONCLUSIONS:Given the high rate of cases satisfying PJI criteria during preoperative workup using our available tests, the synovial alpha-defensin and synovial CRP tests may not be necessary in the routine diagnostic workup of PJI. We suggest that the primary PJI workup process should be based on a stepwise algorithmic approach with the most economical testing necessary to determine a diagnosis first. The use of advanced, commercialized, and costly biomarkers should be utilized only when traditional testing is indeterminate.

Culture-positive (CP) and culture-negative (CN) periprosthetic joint infections (PJI) remain a crucial area of research; however, current studies comparing these infections rely on unstandardized outcome reporting tools. Our study aimed to compare the outcomes of two-stage revision of CP and CN PJI using the standardized Musculoskeletal Infection Society (MSIS) outcome reporting tool. We retrospectively reviewed 138 patients who were diagnosed with PJI and indicated for two-stage revision total knee arthroplasty (rTKA). The majority of patients in both CP and CN cohorts achieved infection control without the need for reoperation (54.1% and 62.5%, respectively). There was a significant difference in the overall distribution of MSIS outcomes (p = 0.043), with a significantly greater rate of CN patients falling into Tier 1 (infection control without the use of suppressive antibiotics) (52.5% versus 29.6%, p = 0.011). There was also a significant difference in the distribution of septic versus aseptic reoperations after 2nd stage (p = 0.013), with more CP reoperations being septic and more CN reoperations being aseptic. The duration from first to second stage was significantly shorter in the CN cohort (p = 0.002). While overall infection control was similar between cohorts, these data suggest that the outcomes of two-stage rTKA are favorable in cases of CN PJI.

INTRODUCTION/BACKGROUND:The importance of identifying how patients choose their healthcare providers has grown with the prevalence of consumer-centric health insurance plans. There is currently a lack of studies exploring the factors associated with how patients select their hip and knee joint arthroplasty surgeons. The purpose of this study was to determine how patients find their arthroplasty providers and the relative importance of various arthroplasty surgeon characteristics. METHODS:An electronic mail survey was sent to 3522 patients who had visited our institution for an arthroplasty surgeon office visit between August 2022 and January 2023. The survey consisted of multiple-choice questions, which aimed to inquire about the patients' referral sources for their current arthroplasty surgeon. In addition, patients were requested to rate the significance of 22 surgeon-related factors, on a scale of 1 (Not Important At All) to 5 (Very Important), in choosing their arthroplasty surgeon. RESULTS:Of the 3522 patients that received the survey, 538 patients responded (15.3%). The most common referral sources were physician referral (50.2%), family/friend referral (27.7%), and self-guided research (24.5%). Of those that were referred by a physician, 54.4% of respondents were referred by another orthopaedic provider. Patients rated board certification (4.72 ± 0.65), in-network insurance status (4.66 ± 0.71), fellowship training (4.50 ± 0.81), bedside manner/personality (4.32 ± 0.86), and facility appearance (4.26 ± 0.81) as the five most important factors in picking an arthroplasty surgeon. Television (1.42 ± 0.83), print (1.50 ± 0.88), and online (1.58 ± 0.93) advertisements, along with social media presence (1.83 ± 1.08), and practice group size (2.97 ± 1.13) were rated as the five least important factors. CONCLUSION/CONCLUSIONS:Patients are most likely to select an arthroplasty surgeon based on referral from other physicians, namely orthopedic surgeons, in addition to board certification status, in-network insurance, and fellowship training. Overall, these findings highlight the importance of physician credentials and reputation within the orthopaedic community in order to attract and retain patients.

Postoperative stiffness is a challenging problem in the setting of primary total knee arthroplasty. There remains a relatively high prevalence of patients suffering from this condition, and it can lead to unsatisfactory outcomes and need for revision surgery as well as a large financial burden on the health care system. There are a number of factors that predispose patients to developing arthrofibrosis, including patient-specific factors and intraoperative and postoperative considerations. Arthrofibrosis can be treated effectively in the early stages with manipulation under anesthesia with or without lysis of adhesions, however, those who fail to respond to these interventions may require revision surgery, which generally has poorer outcomes when performed for this indication. Current research is focused on understanding the pathologic cascade of arthrofibrosis and novel targeted therapeutics that may decrease stiffness in these patients and improve outcomes.

BACKGROUND:Isolated acetabular component revision is an effective treatment for revision total hip arthroplasty patients who have well-fixed femoral implants. We aimed to evaluate the modes of acetabular failure following primary total hip arthroplasty and to identify factors associated with increased morbidities and postoperative outcomes. METHODS:We conducted a retrospective analysis and identified 318 isolated aseptic acetabular revisions. We separated patients by ≤90 days, 91 days to 2 years, and >2 years for acetabular revisions and compared demographics, reasons for revision, 90-day readmissions, rerevisions, and postrevision infections. Revisions ≤90 days, 91 days to 2 years, and >2 years accounted for 10.7, 19.2, and 70.1% of revisions, respectively. Revisions ≤90 days, 91 days to 2 years, and >2 years had their primary total hip arthroplasty at a mean age of 66, 63, and 55 years (P < .001), respectively. RESULTS:Revisions within 90 days were mainly indicated for dislocation/instability (58.8%) or periprosthetic fracture (23.5%) while revisions over 2 years were indicated for polyethylene wear/osteolysis (37.2%). Patients with revisions past 90 days were more likely to require rerevision compared to patients with revisions within 90 days (P < .001). There were no differences in readmissions (P = .28) or infection rates (P = .37). CONCLUSIONS:Acetabular revisions within 90 days were more commonly indicated for instability and periprosthetic fracture, while those over 2 years were indicated for polyethylene wear. Revisions past 90 days were more likely to require subsequent rerevisions without increased 90-day readmissions or infections. LEVEL III EVIDENCE/METHODS:Retrospective cohort study.