Cumulative Intraarticular Injections Are Not a Risk Factor for Periprosthetic Joint Infection Following total Knee Arthroplasty.

BACKGROUND: While injections within 90 days prior to total knee arthroplasty (TKA) are associated with an increased risk of periprosthetic joint infection (PJI), there is a paucity of literature regarding the impact of cumulative injections on PJI risk. This study was conducted to assess the association between cumulative corticosteroid and hyaluronic acid (HA) injections and PJI risk following TKA. METHODS: This retrospective study using an injection database included patients undergoing TKA with a minimum 1-year follow-up from 2015 to 2020. Patients with injections within 90 days prior to surgery were excluded. The sum of corticosteroid and HA injections within five years prior to TKA was recorded. The primary outcome was PJI within 90 days following TKA. Area under the curve (AUC) values were calculated for a cumulative number of injections. RESULTS: 648 knees with no injections and 672 knees with injections prior to TKA were included, among whom 243 received corticosteroids, 151 received HA, and 278 received both. No significant differences in early PJI rates existed between patients who received injections (0.60%) or not (0.93%) (P = .541). No significant differences existed in early PJI rates between patients injected with corticosteroids (0.82%), HA (0.66%), or both (0.36%) (P = .832). No cutoff number of injections was predictive for PJI. DISCUSSION: A cumulative amount of steroid or HA injections, if given more than 90 days prior to TKA, does not appear to increase the risk of PJI within 90 days postoperatively. Multiple intraarticular corticosteroid injections and HA injections may be safely administered before TKA, without increased risk for early PJI.

A Time-Driven Activity-Based Costing Analysis of Simultaneous Versus Staged Bilateral Total Hip Arthroplasty and Total Knee Arthroplasty.

BACKGROUND: Although studies have compared the claims costs of simultaneous and staged bilateral total hip arthroplasty (THA) and total knee arthroplasty (TKA), whether a simultaneous procedure is cost-effective to the facility remains unknown. This study aimed to compare facility costs and perioperative outcomes of simultaneous vs staged bilateral THA and TKA. METHODS: We reviewed a consecutive series of 560 bilateral THA (170 staged and 220 simultaneous) and 777 bilateral TKA (163 staged and 451 simultaneous). Itemized facility costs were calculated using time-driven activity-based costing. Ninety-day outcomes were compared. Margin was standardized to unadjusted Medicare Diagnosis Related Group payments (simultaneous, $18,523; staged, $22,386). Multivariate regression was used to determine the independent association between costs/clinical outcomes and treatment strategy (staged vs simultaneous). RESULTS: Simultaneous bilateral patients had significantly lower personnel, supply, and total facility costs compared with staged patients with no difference in 90-day complications between the groups. Multivariate analyses showed that overall facility costs were $1,210 lower in simultaneous bilateral THA (P < .001) and $704 lower in TKA (P < .001). Despite lower costs, margin for the facility was lower in the simultaneous group ($6,569 vs $9,225 for THA; $6,718 vs $10,067 for TKA; P < .001). CONCLUSION: Simultaneous bilateral TKA and THA had lower facility costs than staged procedures because of savings associated with a single hospitalization. With the increased Medicare reimbursement for 2 unilateral procedures, however, margin was higher for staged procedures. In the era of value-based care, policymakers should not penalize facilities for performing cost-effective simultaneous bilateral arthroplasty in appropriately selected patients.

Orthopedic Specialty Hospital Reasons for Transfer and Subsequent Outcomes.

BACKGROUND: Surgical specialty hospitals provide patients, surgeons, and staff with a streamlined approach to elective surgery but may not be equipped to handle all complications arising postoperatively. The purpose of this study is to evaluate the immediate postoperative and 90-day outcomes of patients who were transferred from a high-volume specialty hospital following primary total hip arthroplasty (THA) or total knee arthroplasty (TKA). METHODS: All patients who were admitted to one orthopedic specialty hospital for primary THA or TKA between January 2015 and December 2019, and subsequently transferred to a tertiary care hospital, were identified and propensity matched to nontransferred patients. Emergency department visits, complications, readmissions, mortality, and revisions within 90 days of surgery were identified for each group. RESULTS: There were 26 TKAs (0.78%) and 20 THAs (0.48%) transferred, representing 0.62% of all primary THAs and TKAs performed over the study duration. Arrhythmia and chest pain were the most common reasons for transfer. Ninety-day readmissions were significantly higher in the transfer group (15.2% vs 4.3%, P = .020) with an odds ratio for readmission after transfer of 3.9 (95% confidence interval 1.3-12.4). Overall complications and orthopedic complications did not differ significantly, although transferred patients had a higher rate of medical complications (13.0% vs 2.2%, P = .008) with an odds ratio of 6.7 (95% confidence interval 1.6-28.2). CONCLUSION: Transfer from a specialty hospital is rarely required following primary TKA and THA. Although not at increased risk for orthopedic complications, these transferred patients are at increased risk for readmissions and medical complications within the first 90 days of their care, necessitating increased vigilance.

Cemented Versus Cementless Total Knee Arthroplasty in Obese Patients With Body Mass Index ≥35 kg/m2: A Contemporary Analysis of 812 Patients.

BACKGROUND: Cemented total knee arthroplasty (TKA) has been shown to have higher failure rates in obese patients, and cementless TKA may provide more durable fixation. This study compared outcomes and survivorship of obese patients undergoing cemented and cementless TKA of the same modern design. METHODS: We identified a consecutive series of 406 primary cementless TKA performed in obese patients with body mass index (BMI) ≥35 kg/m2 in 2013-2018. Each case was matched 1:1 with 406 cemented TKA based on age, sex, BMI, bearing surface, and year of surgery. Knee Injury and Osteoarthritis Outcome Score for Joint Replacement and Short Form-12 were collected preoperatively, at 6 months and 2 years. Implant survivorship was recorded at mean 4.0 years (range 2.0-7.8). RESULTS: There was no difference in mean BMI between the cemented (38.6 ± 3.4 kg/m2; range, 35-60) and cementless cohorts (38.7 ± 3.3 kg/m2; range, 35-54; P = .706). Both groups had similar final postoperative scores and improvement in scores at 2 years. Furthermore, a similar percentage met the minimal clinically important difference (Knee Injury and Osteoarthritis Outcome Score for Joint Replacement, 70.0% vs 71.2%, P = .700; Short Form-12 Physical, 74.1% vs 70.4%, P = .240). Both groups demonstrated high 7-year survivorship free from aseptic revision (99.0% vs 99.5%, P = .665). CONCLUSION: Obese patients with BMI ≥35 kg/m2 undergoing cementless and cemented TKA of the same modern design had similar outcomes and survivorship at early to mid-term follow-up. Continued surveillance of this high-risk population is necessary.

Comparing Patient-reported Outcomes to Patient Satisfaction After a Microdiscectomy for Patient's With a Lumbar Disk Herniation.

STUDY DESIGN: A retrospective cohort study. OBJECTIVE: The objective of this study was to determine if patient satisfaction is predicted by improvement in health-related quality of life (HRQOL) metrics. SUMMARY OF BACKGROUND DATA: Patient satisfaction is becoming an increasingly common proxy for treatment quality; however, the correlation between patient satisfaction and HRQOL outcome metrics following a lumbar disk herniation is unclear. METHODS: Patients enrolled in the Spine Patient Outcomes Research Trial (SPORT) study were prospectively enrolled at 13 institutions. A retrospective subgroup analysis of prospectively collected data from the SPORT trial was performed. Receiver operating characteristic curves were used to determine if improvement in HRQOL metrics could accurately identify patient satisfaction. HRQOL metrics included: Short Form-36 (SF-36), Oswestry Disability Index (ODI), Sciatica Bothersomeness Index, Back Pain Bothersomeness Scale, and Leg Pain Bothersomeness Scale. RESULTS: A total of 709 patients who underwent surgery and 319 patients treated without surgery were included. In the surgical cohort, receiver operating characteristic curve analysis demonstrated that SF-36 Physical Component Summary improvement had moderate accuracy [area under the curve (AUC)=0.77 (95% confidence interval, CI: 0.73-0.82)] at predicting satisfaction at 3 months, and it had excellent accuracy at predicting satisfaction at 2 years [AUC=0.81 (95% CI: 0.77-0.85)] and 4 years [AUC=0.81 (95% CI: 0.76-0.85)]. Absolute Physical Component Summary score had excellent accuracy at 3 months [AUC=0.83 (95% CI: 0.79-0.87)], 2 years [AUC=0.87 (95% CI: 0.84-0.9)] and 4 years [AUC=0.84 (95% CI: 0.8-0.89)]. Similarly improvement in the ODI had moderate accuracy of predicting satisfaction at 3 months [AUC=0.77 (95% CI: 0.72-0.81)], 2 years [AUC=0.78 (95% CI: 0.74-0.82)] and 4 years [AUC=0.78 (95% CI: 0.73-0.83)], and the absolute ODI score had excellent accuracy at 3 months [AUC=0.85 (95% CI: 0.82-0.89)], 2 years [AUC=0.89 (95% CI: 0.86-0.92)], and 4 years [AUC=0.88 (95% CI: 0.85-0.92)]. CONCLUSIONS: HRQOL metrics can accurately predict patient satisfaction with symptoms at 3 months, 2 years, and 4 years after surgical intervention for a lumbar disk herniation. Absolute outcome scores were somewhat more predictive than change scores.