Faculty Bibliography

INTRODUCTION/BACKGROUND:Cement burns following arthroplasty pro-cedures are a rare but serious complication. To the authors' knowledge, this report is the first of its kind in total knee arthroplasty. CASE/METHODS:A 61-year-old female underwent an otherwise rou-tine left total knee arthroplasty. On postoperative day one, a 3 cm by 3 cm cement burn was noted on the distal aspect of the popliteal fossa of the operative leg. The burn was noted to be a full-thickness (third degree) burn that required plastic surgery burn service management and limited the patient's postoperative recovery and function. CONCLUSIONS:Cement burns of the skin following total joint arthroplasty are rare, though when they do occur, they can cause significant pain and distress. Recognizing the depth of the skin involvement is important to determine the burn classification, treatment, and ultimately the prognosis to optimize outcomes.

BACKGROUND/UNASSIGNED:Many of the current total hip arthroplasty (THA) planning tools only consider sagittal pelvic tilt in the standing and relaxed sitting positions. Considering that the risk of postoperative dislocation is higher when bending forward or in sit-to-stand move, sagittal pelvic tilt in the flexed seated position may be more relevant for preoperative planning. We hypothesized that there was a significant difference in sagittal pelvic tilt between the relaxed sitting and flexed seated positions as measured by the sacral slope in preoperative and postoperative full-body radiographs. METHODS/UNASSIGNED:This was a multicenter retrospective analysis of the preoperative and postoperative simultaneous biplanar full-body radiographs of 93 primary THA patients in standing, relaxed sitting, and flexed seated positions. The sagittal pelvic tilt was measured using the sacral slope relative to the horizontal line. RESULTS/UNASSIGNED:< .0001). This difference was >10° in 51 patients (54.9%) and >30° in 14 patients (15.1%) postoperatively. CONCLUSIONS/UNASSIGNED:There was a significant difference in sagittal pelvic tilt between the relaxed and flexed seated positions. A flexed seated view provides valuable information that might be more relevant for preoperative THA planning in order to prevent postoperative THA instability.

INTRODUCTION/BACKGROUND:Prior studies have demonstrated an association between time to revision total knee arthroplasty (rTKA) and indication; however, the impact of early versus late revision on post-operative outcomes has not been reported. MATERIALS AND METHODS/METHODS:A retrospective, observational study examined patients who underwent unilateral, aseptic rTKA at an academic orthopedic hospital between 6/2011 and 4/2020 with > 1-year of follow-up. Patients were early revisions if they were revised within 2 years of primary TKA (pTKA) or late revisions if revised after greater than 2 years. Patient demographics, surgical factors, and post-operative outcomes were compared. RESULTS:470 rTKA were included (199 early, 271 late). Early rTKA patients were younger by 2.5 years (p = 0.002). The predominant indications for early rTKA were instability (28.6%) and arthrofibrosis/stiffness (26.6%), and the predominant indications for late rTKA were aseptic loosening (45.8%) and instability (26.2%; p < 0.001). Late rTKA had longer operative times (119.20 ± 51.94 vs. 103.93 ± 44.66 min; p < 0.001). There were no differences in rTKA type, disposition, hospital length of stay, all-cause 90-day emergency department visits and readmissions, reoperations, and number of re-revisions. CONCLUSIONS:Aseptic rTKA performed before 2 years had different indications but demonstrated similar outcomes to those performed later. Early revisions had shorter surgical times, which could be attributed to differences in rTKA indication. LEVEL OF EVIDENCE/METHODS:III, retrospective observational analysis.

AIMS/UNASSIGNED:Revision total knee arthroplasty (rTKA) is a technically challenging and costly procedure. It is well-documented that primary TKA (pTKA) have better survivorship than rTKA; however, we were unable to identify any studies explicitly investigating previous rTKA as a risk factor for failure following rTKA. The purpose of this study is to compare the outcomes following rTKA between patients undergoing index rTKA and those who had been previously revised. METHODS/UNASSIGNED:This retrospective, observational study reviewed patients who underwent unilateral, aseptic rTKA at an academic orthopaedic speciality hospital between June 2011 and April 2020 with > one-year of follow-up. Patients were dichotomized based on whether this was their first revision procedure or not. Patient demographics, surgical factors, postoperative outcomes, and re-revision rates were compared between the groups. RESULTS/UNASSIGNED:= -0.102; p = 0.251). CONCLUSION/UNASSIGNED:Multiply revised TKA had worse outcomes, with higher rates of facility discharge, longer operative times, and greater reoperation and re-revision rates compared to index rTKA.

BACKGROUND:Airborne biologic particles (ABPs) can be measured intraoperatively to evaluate operating room (OR) sterility. Our study examines the role of OR size on air quality and ABP count in primary total hip arthroplasty (THA). METHODS:at a single academic institution from April 2019 to June 2020. Temperature, humidity, and ABP count per minute were recorded with a particle counter intraoperatively and cross-referenced with surgical data from the electronic health records using procedure start and end times. Descriptive statistics were used to evaluate differences in variables. P-values were calculated using t-test and chi-squared test. RESULTS:A total of 116 primary THA cases were included: 18 (15.5%) in the "small" OR and 98 (84.5%) in the "large" OR. Between-group comparisons revealed significant differences in temperature (small OR: 20.3 ± 1.23 C versus large OR: 19.1 ± 0.85 C, P < .0001) and relative humidity (small OR: 41.1 ± 7.24 versus large OR: 46.9 ± 7.56, P < .001). Significant percent decreases in ABP rates for particles measuring 2.5 um (-125.0%, P = .0032), 5.0 um (-245.0%, P = .00078), and 10.0 um (-413.9%, P = .0021) were found in the large OR. Average time spent in the OR was significantly longer in the large OR (174 ± 33 minutes) compared to the small OR (151 ± 14 minutes) (P = .00083). CONCLUSION/CONCLUSIONS:Temperature and humidity differences and significantly lower ABP counts were found in the large compared to the small OR despite longer average time spent in the large OR, suggesting the filtration system encounters less particle burden in larger rooms. Further research is needed to determine the impact this may have on infection rates.

PURPOSE/OBJECTIVE:The previous literature suggests that 25-30% of patients who undergo total knee arthroplasty (TKA) are using opioids prior to their surgery. This study aims to investigate the effect of preoperative opioid use on clinical outcomes and patient-reported outcome measures (PROMs) following TKA. METHODS:We retrospectively reviewed 329 patients who underwent primary TKA from 2019 to 2020, answered the preoperative opioid survey, and had available PROMs. Patients were stratified into two groups based on whether they were taking opioids preoperatively or not: 26 patients with preoperative opioid use (8%) and 303 patients without preoperative opioid use (92%) were identified. Demographics, clinical data, and PROMs [Forgotten Joint Score (FJS-12), Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS, JR), and Veterans RAND-12 Physical and Mental components (VR-12 PCS and MCS)] were collected. Demographic differences were assessed with Chi-square and independent sample t-tests. Outcomes were compared using multilinear regression analysis, controlling for demographic differences. RESULTS:Preoperative opioid users had a significantly longer length-of-stay (2.74 vs. 2.10; p = 0.010), surgical time (124.65 vs. 105.69; p < 0.001), and were more likely to be African-American (38.5 vs. 14.2%; p = 0.010) compared to preoperative opioid-naive patients. Postoperative FJS-12 did not statistically differ between the two groups. While preoperative KOOS, JR scores were significantly lower for preoperative opioid users (41.10 vs. 46.63; p = 0.043), they did not significantly differ postoperatively. Preoperative VR-12 PCS did not statistically differ between the groups; however, both 3-month (33.87 vs. 38.41; p = 0.049) and 1-year (36.01 vs. 44.73; p = 0.043) scores were significantly lower for preoperative opioid users. Preoperative VR-12 MCS was significantly lower for preoperative opioid users (46.06 vs. 51.06; p = 0.049), though not statistically different postoperatively. CONCLUSION/CONCLUSIONS:At 8%, our study population had a lower percentage of opioid users than previously reported in the literature. Preoperative opioid users had longer operative times and length of stay compared to preoperatively opioid-naive patients. While both cohorts achieved similar clinical benefits following TKA, preoperative opioid users reported lower postoperative scores with respect to VR-12 PCS scores. LEVEL III EVIDENCE/METHODS:Retrospective Cohort.

INTRODUCTION/BACKGROUND:The International Classification of Diseases-10 Procedure Code System (ICD-10-PCS) introduced oxidized zirconium and niobium (OxZi) procedural codes to the types of femoral head bearing surfaces in 2017. These codes aimed to increase procedural specificity in coding and improve data collection through administrative claims databases. This study aimed to assess the accuracy of ICD-10-PCS coding for femoral head bearing surfaces (cobalt chrome/metal, ceramic, and OxZi) in hip procedures. MATERIAL AND METHODS/METHODS:, 2021 at a large, urban academic hospital was conducted. Operative reports and implant logs were queried to determine the femoral head bearing surface, which was used during the THA. These results were then compared to the ICD-10-PCS codes in the billing records. Coding accuracy was subsequently determined and statistical differences between the three groups were evaluated. RESULTS:ICD-10-PCS coding was accurate for 90.8% (5634/6204) of cases. Coding accuracy for ceramic femoral heads (95.4%, 4171/4371) was significantly greater than that of both cobalt chrome/metal (73.7%, 606/822; p<0.001) and OxZi (84.8%, 857/1011; p<0.001) femoral heads. CONCLUSION/CONCLUSIONS:While coding for ceramic femoral heads was very accurate, OxZi and cobalt chrome/metal femoral heads were miscoded at a rate of approximately 20%. These inaccuracies call for further evaluation of the ICD-10-PCS coding process to ensure that conclusions drawn from clinical research performed through administrative claims databases are not subject to error.

BACKGROUND:As value-based reimbursement models mature, understanding the potential trade-off between inpatient lengths of stay and complications or need for costly post-acute care becomes more pressing. Understanding and predicting a patient's expected baseline length of stay may help providers understand how best to decide optimal discharge timing for high-risk total joint arthroplasty (TJA) patients. MATERIALS AND METHODS/METHODS:A retrospective review was conducted of 37,406 primary total hip (17,134, 46%) and knee (20,272, 54%) arthroplasties performed at two high-volume, geographically diverse, tertiary health systems during the study period. Patients were stratified by 3 binary outcomes for extended inpatient length of stay: 72+ hours (29%), 4+ days (11%), or 5+ days (5%). The predictive ability of over 50 sociodemographic/comorbidity variables was tested. Multivariable logistic regression models were created using Institution #1 (derivation), with accuracy tested using the cohort from Institution #2 (validation). RESULTS:During the study period, patients underwent an extended length of stay with a decreasing frequency over time, with privately-insured patients having a significantly shorter length of stay relative to those with Medicare (1.9 vs 2.3 days, p < 0.0001). Extended-stay patients also had significantly higher 90-day readmission rates (p < 0.0001), even when excluding those discharged to post-acute care (p < 0.01). Multivariable logistic regression models created from the training cohort demonstrated excellent accuracy (area under the curve (AUC): 0.755, 0.783, 0.810), and performed well under external validation (AUC: 0.719, 0.743, 0.763). Many important variables were common to all 3 models, including age, sex, American Society of Anesthesiologists (ASA) score, body mass index, marital status, bilateral case, insurance type, and 13 comorbidities. DISCUSSION/CONCLUSIONS:An online, freely-available, pre-operative clinical decision tool accurately predicts risk of extended inpatient length of stay after TJA. Many risk factors are potentially modifiable, and these validated tools may help guide clinicians in pre-operative patient counseling, medical optimization, and understanding optimal discharge timing.

BACKGROUND:Girdlestone resection arthroplasty is a salvage procedure for hip periprosthetic joint infection (PJI) that controls infection and reduces chronic pain, but may result in limited postoperative joint function. The aim of this study was to assess physical function and mental health after Girdlestone. METHODS:This was a multicenter, prospective study evaluating patients with Girdlestone. The Prosthesis Evaluation Questionnaire (PEQ) and patient-reported outcomes measurement information system (PROMIS) global physical health and mental health surveys were administered postoperatively via telephone. The PEQ consists of four scales (ie, ambulation, frustration, perceived response, and social burden) with scores ranging from 0 to 10. The PROMIS measures generated T-scores (mean: 50, standard deviation: 10) that enable comparison to the general population. RESULTS:Thirty-five patients completed all surveys. The average time from procedure to survey completion was 6 years (range, 1 to 20). The median scores for the ambulation, frustration, perceived response, and social burden scales of the PEQ were 0.0 [interquartile range: 0-4.1], 6.0 [3.0-9.3], 9.0 [7.2-10.0], and 7.5 [4.3-9.5]. The median raw scores of the PROMIS global physical health and mental health were 11.91 [interquartile range: 9-14] and 14.0 [10.0-16.0]. These corresponded to average T scores of 39.7 (standard error : 4.3) for physical health and 46.1 (standard error: 3.8) for mental health, which were 10.3 points and 3.9 points below the average score in the United States general population, respectively. CONCLUSION/CONCLUSIONS:Girdlestone can have a substantial negative impact on physical functions; however, mental health and social interaction may be only moderately affected. These outcomes can be used to guide patient expectations, as this procedure may be necessary in certain salvage scenarios.