Faculty Bibliography

INTRODUCTION/BACKGROUND:Removal of primary total knee arthroplasty (TKA) and primary total hip arthroplasty (THA) from the inpatient-only (IPO) list has financial implications for both patients and institutions. The aim of this study was to evaluate and compare financial parameters between patients designated for inpatient versus outpatient total joint arthroplasty (TJA) surgery. METHODS:We reviewed all patients who underwent TKA or THA after these procedures were removed from the IPO list. Patients were stratified into cohorts based on inpatient or outpatient status, procedure type, and insurance type. This included 5,284 patients, of which 4,279 were designated inpatient while 1,005 were designated outpatient. Patient demographic, perioperative, and financial data including per patient revenues, total and direct costs, and contribution margins (CMs) were collected. Data were compared using t-tests and Chi-square tests. RESULTS:Among Medicare patients receiving THA, CM was 89.1% lower for the inpatient cohort when compared to outpatient (p<0.001), though there was no significant difference between cohorts for TKA (p=0.501). Among patients covered by Medicaid or Government-managed plans, CM was 120.8% higher for inpatients receiving THA (p<0.001) when compared to outpatients and 136.3% higher for inpatients receiving TKA (p<0.001). CONCLUSION/CONCLUSIONS:Our analyses showed that recent costs associated with inpatient stay inconsistently match or outpace additional revenue, causing CM to vary drastically depending on insurance and procedure type. For Medicare patients receiving THA, inpatient surgery is financially disincentivized leaving this vulnerable patient population at risk of losing access to care.

INTRODUCTION/BACKGROUND:High body mass index (BMI) and wound drainage following total joint arthroplasty (TJA) can lead to wound healing complications and periprosthetic joint infection. Silver-embedded occlusive dressings and negative pressure wound therapy (NPWT) have been shown to reduce these complications. The purpose of this prospective trial was to compare the effect of silver-embedded dressings and NPWT on wound complications in patients with BMI ≥ 35 m/kg2 undergoing TJA. METHODS:and were undergoing primary TJA between October 2017 and February 2020. Patients who underwent revision surgery, or those with an active infection, previous scar, history of wound healing complications, post-traumatic degenerative joint disease with hardware, or inflammatory arthritis were excluded. Patients were randomized to receive either a silver-embedded occlusive dressing (control) or NPWT. Frequency distributions, means, and standard deviations were used to describe patient demographics, postoperative complications, 90-day readmissions, and reoperations. T-test and chi-squared tests were used to test for significant differences between continuous and categorical variables, respectively. RESULTS:Two hundred-thirty patients with 3-month follow-up were included. One-hundred-fifteen patients received the control and 115 patients received NPWT. There were six patients (5.2%) in the control group with wound complications (drainage: n = 5, non-healing wound: n = 1) and two patients (1.7%) in the NPWT with complications (drainage: n = 2). There were no 90-day readmissions in the control group versus two (1.8%) 90-day readmissions in the NPWT group. Finally, three patients (2.6%) in the control group underwent reoperations (irrigation and debridement [I&D], I&D with modular implant exchange, and implant revision), while none in the NPWT group had undergone reoperation. The two groups showed insignificant differences in wound complications (p = 0.28), 90-day readmissions (p = 0.50), and reoperations (p = 0.25). CONCLUSION/CONCLUSIONS:Patients with BMI ≥ 35 m/kg2 undergoing TJA have no statistical difference in early wound complications, readmissions, or reoperations when treated with either silver-embedded dressings or NPWT.

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:Stiffness and decreased range of motion frequently lead to hindrance of activities of daily living and dissatisfaction follow total knee arthroplasty (TKA). This study aims to evaluate the effect of non-aspirin (ASA) chemoprophylaxis and determine patient-related risk factors for stiffness and need for manipulation under anesthesia (MUA) following primary TKA. MATERIALS AND METHODS/METHODS:A review of all patients undergoing primary TKA from 2013 to 2019 at a single academic orthopedic hospital was conducted. The primary outcome measure was MUA performed post-operatively. Chi-square analysis and Mann-Whitney U test were used to determine statistically significant relationships between risk factors and outcomes. Significance was set at p < 0.05. Univariate logistic regression was performed to control for identified independent risk factors for MUA. RESULTS:A total of 11,550 patients undergoing primary TKA from January 2013 to September 2019 at an academic medical center were included in the study. Increasing age and Charlson Comorbidity Index were associated with statistically significant decreased odds of MUA (0.93, 95% CI: 0.92-0.94, p < 0.001, OR 0.71, 95% CI 0.63-0.79, p < 0.001). Active smokers had a 2.01 increased odds of MUA (OR 2.01, 95% CI 1.28, 3.02, p < 0.001). There was no significant difference in rates of MUA between ASA and non-ASA VTE prophylaxis (p 0.108). CONCLUSIONS:Younger age, lower CCI, and history of smoking are associated with a higher rate, while different chemical VTE prophylaxis does not influence rate of MUA after TKA. Arthroplasty surgeons should consider these risk factors when counseling patient preoperatively. Understanding each patients' risk for MUA allows surgeons to appropriately set preoperative expectations and reasonable outcome goals.

INTRODUCTION/BACKGROUND:Optimization of patient outcomes and identification of factors to improve the surgical workflow are increasingly important. Operating room time is one modifiable factor that leads to greater hospital efficiency as well as improved outcomes such as shorter length of stay and fewer infections and readmissions. The aim of this study was to identify factors associated with operative time disparities in total knee arthroplasty (TKA). METHODS:A retrospective review of 7659 consecutive primary TKA cases was conducted. Patient demographic data, discrete operating room (OR) times, use of technology (i.e. robotic-assisted surgery, computer navigation), surgeon experience and the level of training of the first assistant were collected. Multivariate regression analysis was used to determine the effect of hospital characteristics on operative times. Operative times of five minutes or greater were considered to be clinically significant. RESULTS:While the use of technology (182.64 ± 39.85 vs 158.70 ± 37.45 min; B = 26.09; p < 0.0001) and greater surgeon experience (162.14 ± 39.87 vs 158.69 ± 33.18 min, B = 3.15, p = 0.002) were found to increase OR times, level of training of the first assist (161.65 vs 156.4 min; Β = - 0.264; p = 0.487) did not. Of the discrete OR times examined, incision time and total time under anesthesia were negatively impacted by the use of technology. CONCLUSION/CONCLUSIONS:Use of technology was the only study variable found to significantly increase OR times. With increased operative times and limited evidence that technology improves long-term patient outcomes, surgeons should carefully consider the benefits and cost of technology in TKA.

PURPOSE/OBJECTIVE:Aseptic loosening is a common cause of implant failure following total knee arthroplasty (TKA). Cement penetration depth is a known factor that determines an implant's "strength" and plays an important role in preventing aseptic loosening. Tourniquet use is thought to facilitate cement penetration, but its use has mixed reviews. The aim of this study was to compare cement penetration depth between tourniquet and tourniquet-less TKA patients. METHODS:A multicenter retrospective review was conducted. Patients were randomized preoperatively to undergo TKA with or without the use of an intraoperative tourniquet. The variables collected were cement penetration measurements in millimeters (mm) within a 1-month post-operative period, length of stay (LOS), and baseline demographics. Measurements were taken by two independent raters and made in accordance to the zones described by the Knee Society Radiographic Evaluation System and methodology used in previous studies. RESULTS:A total of 357 TKA patients were studied. No demographic differences were found between tourniquet (n = 189) and tourniquet-less (n = 168) cohorts. However, the tourniquet cohort had statistically, but not clinically, greater average cement penetration depth [2.4 ± 0.6 mm (range 1.2-4.1 mm) vs. 2.2 ± 0.5 mm (range 1.0-4.3 mm, p = 0.01)]. Moreover, the tourniquet cohort had a significantly greater proportion of patients with an average penetration depth within the accepted zone of 2 mm or greater (78.9% vs. 67.3%, p = 0.02). CONCLUSION/CONCLUSIONS:Tourniquet use does not affect average penetration depth but increases the likelihood of achieving optimal cement penetration depth. Further study is warranted to determine whether this increased likelihood of optimal cement penetration depth yields lower revision rates.

Tourniquet use creates a reduced blood surgical field during total knee arthroplasty (TKA), however, prolonged ischemia may cause postoperative tourniquet complications. To understand the effects of tourniquet-induced ischemia, we performed a prospective observational study using quantitative broadband diffuse optical spectroscopy (DOS) to measure tissue hemodynamics and water and lipid concentrations before, during, and after tourniquet placement in subjects undergoing TKA. Data was collected for 6 months and, of the total subjects analyzed (n = 24), 22 were primary TKAs and 2 were revision TKA cases. We specifically investigated tourniquet-induced hemodynamics based upon subject-specific tissue composition and observed a significant relationship between the linear rate of deoxygenation after tourniquet inflation and water/lipid ratio (W/L, p < 0.0001) and baseline somatic tissue oxygen saturation, StO₂ (p = 0.05). Subjects with a low W/L ratio exhibited a lower tissue metabolic rate of oxygen consumption, (tMRO₂ ) (p = 0.008). Changes in deoxyhemoglobin [HbR] (p = 0.009) and lipid fraction (p = 0.001) were significantly different between high and low W/L subject groups during deoxygenation. No significant differences were observed for hemodynamics during reperfusion and total tourniquet time was neither significantly related to the hemodynamic hyperemic response (p = 0.73) nor the time to max StO₂ after tourniquet release (p = 0.57). In conclusion, we demonstrate that DOS is capable of real-time monitoring of tissue hemodynamics distal to the tourniquet during TKA, and that tissue composition should be considered. DOS may help surgeons stratify hemodynamics based upon tissue composition and eventually aid the preoperative risk assessment of vascular occlusions from tourniquet use during TKA.

INTRODUCTION/BACKGROUND:Increasing age and hip fractures are considered risk factors for post-operative complications in total hip arthroplasty (THA). Consequently, older adults undergoing THA due to hip fracture may have different outcomes and require additional healthcare resources than younger patients. This study aimed to identify the influence of age on discharge disposition and 90-day outcomes of THA performed for hip fractures in patients ≥ 80 years to those aged < 80. MATERIALS AND METHODS/METHODS:A retrospective review of 344 patients who underwent primary THA for hip fracture from 2011 to 2021 was conducted. Patients ≥ 80 years old were propensity-matched to a control group < 80 years old. Patient demographics, length of stay (LOS), discharge disposition, and 90-day post-operative outcomes were collected and assessed using Chi-square and independent sample t tests. RESULTS:A total of 110 patients remained for matched comparison after propensity matching, and the average age in the younger cohort (YC, n = 55) was 67.69 ± 10.48, while the average age in the older cohort (OC, n = 55) was 85.12 ± 4.77 (p ≤ 0.001). Discharge disposition differed between the cohorts (p = 0.005), with the YC being more likely to be discharged home (52.7% vs. 27.3%) or to an acute rehabilitation center (23.6% vs. 16.4%) and less likely to be discharged to a skilled nursing facility (21.8% vs. 54.5%). 90-day revision (3.6% vs. 1.8%; p = 0.558), 90-day readmission (10.9% vs. 14.5%; p = 0.567), 90-day complications (p = 0.626), and 90-day mortality rates (1.8% vs 1.8%; p = 1.000) did not differ significantly between cohorts. CONCLUSION/CONCLUSIONS:While older patients were more likely to require a higher level of post-hospital care, outcomes and perioperative complication rates were not significantly different compared to a younger patient cohort. Payors need to consider patients' age in future payment models, as discharge disposition comprises a large percentage of post-discharge expenses. LEVEL OF EVIDENCE/METHODS:Level III, Retrospective Cohort Study.