Aims. In the last decade, perioperative advancements have expanded the use of outpatient primary total knee arthroplasty (TKA). Despite this, there remains limited data on expedited discharge after revision TKA. This study compared 30-day readmissions and reoperations in patients undergoing revision TKA with a hospital stay greater or less than 24 hours. The authors hypothesized that expedited discharge in select patients would not be associated with increased 30-day readmissions and reoperations. Methods. Aseptic revision TKAs in the National Surgical Quality Improvement Program database were reviewed from 2013 to 2020. TKAs were stratified by length of hospital stay (greater or less than 24 hours). Patient demographic details, medical comorbidities, American Society of Anesthesiologists (ASA) grade, operating time, components revised, 30-day readmissions, and reoperations were compared. Multivariate analysis evaluated predictors of discharge prior to 24 hours, 30-day readmission, and reoperation. Results. Of 21,610 aseptic revision TKAs evaluated, 530 were discharged within 24 hours. Short-stay patients were younger (63.1 years (49 to 78) vs 65.1 years (18 to 94)), with lower BMI (32.3 kg/m. 2. (17 to 47) vs 33.6 kg/m. 2. (19 to 54) and lower ASA grades. Diabetes, chronic obstructive pulmonary disease, hypertension, and cancer were all associated with a hospital stay over 24 hours. Single component revisions (56.8% (n = 301) vs 32.4% (n = 6,823)), and shorter mean operating time (89.7 minutes (25 to 275) vs 130.2 minutes (30 to 517)) were associated with accelerated discharge. Accelerated discharge was not associated with 30-day readmission and reoperation. Conclusion. Accelerated discharge after revision TKA did not increase short-term complications, readmissions, or reoperations. Further efforts to decrease hospital stays in this setting should be evaluated. Cite this article: Bone Joint J 2022;104-B(12):1323–1328

Aims. Fungal periprosthetic joint infections (PJIs) are rare, but their diagnosis and treatment are highly challenging. The purpose of this study was to investigate the clinical outcomes of patients with fungal PJIs treated with two-stage exchange knee arthroplasty combined with prolonged antifungal therapy. Methods. We reviewed our institutional joint arthroplasty database and identified 41 patients diagnosed with fungal PJIs and treated with two-stage exchange arthroplasty after primary total knee arthroplasty (TKA) between January 2001 and December 2020, and compared them with those who had non-fungal PJIs during the same period. After propensity score matching based on age, sex, BMI, American Society of Anesthesiologists grade, and Charlson Comorbidity Index, 40 patients in each group were successfully matched. The surgical and antimicrobial treatment, patient demographic and clinical characteristics, recurrent infections, survival rates, and relevant risk factors that affected joint survivorship were analyzed. We defined treatment success as a well-functioning arthroplasty without any signs of a PJI, and without antimicrobial suppression, at a minimum follow-up of two years from the time of reimplantation. Results. The fungal PJI group demonstrated a significantly worse treatment success rate at the final follow-up than the non-fungal PJI group (65.0% (26/40) vs 85.0% (34/40); p < 0.001). The mean prosthesis-free interval was longer in the fungal PJI group than in the non-fungal PJI group (6.7 weeks (SD 5.8) vs 4.1 weeks (SD 2.5); p = 0.020). The rate of survivorship free from reinfection was worse in the fungal PJI group (83.4% (95% confidence interval (CI) 64.1 to 92.9) at one year and 76.4% (95% CI 52.4 to 89.4) at two years) than in the non-fungal PJI group (97.4% (95% CI 82.7 to 99.6) at one year and 90.3% (95% CI 72.2 to 96.9) at two years), but the differences were not significant (p = 0.270). Cox proportional hazard regression analysis identified the duration of the prosthesis-free interval as a potential risk factor for failure (hazard ratio 1.128 (95% CI 1.003 to 1.268); p = 0.043). Conclusion. Fungal PJIs had a lower treatment success rate than non-fungal PJIs despite two-stage revision arthroplasty and appropriate antifungal treatment. Our findings highlight the need for further developments in treating fungal PJIs. Cite this article: Bone Joint J 2023;105-B(12):1286–1293

Aims. This study compared the cobalt and chromium serum ion concentration of patients treated with two different metal-on-metal (MoM) hinged total knee arthroplasty (TKA) systems, as well as a titanium nitride (TiN)-coated variant. Methods. A total of 63 patients (65 implants) were treated using either a MoM-coated (n = 29) or TiN-coated (n = 7) hinged TKA (GenuX mobile bearing, MUTARS; Implantcast, Germany) versus the BPKS (Brehm, Germany) hinged TKA (n = 27), in which the weight placed on the MoM hinge is diffused through a polyethylene (PE) inlay, reducing the direct load on the MoM hinge. Serum cobalt and chromium ion concentrations were assessed after minimum follow-up of 12 months, as well as functional outcome and quality of life. Results. No differences in mean age (69 years, 40 to 86), mean age adapted Charlson Comorbidity Index (3.1 (SD 1.4)), mean BMI (29.2 kg/m. 2. (SD 5.8)), or number of other implants were observed between groups. Significant improvements in outcome scores and pain levels were achieved for all groups, and there was no difference in quality of life (12-Item Short-Form Health Survey questionnaire (SF-12)). Mean cobalt and chromium ion levels were significantly higher for the GenuX versus the BPKS hinged TKA (GenuX vs BPKS: cobalt: 16.3 vs 9.4 µg/l; chromium: 9.5 vs 5.2 µg/l). The TiN-coated implants did not appear to confer improvement in the metal ion levels. Metal ion concentrations above 7 µg/l were detected in 81%(29/36) of GenuX patients versus 41% (11/27) in the BPKS group. No GenuX patients had normal levels under 2 µg/l, versus 22% of BPKS patients. No significant reduction in outcome scores was observed regardless of the metal ion levels, whereas higher work-related activity was correlated with higher chromium concentrations. Conclusion. Hinged TKA, using MoM hinges, resulted in critically high cobalt and chromium ion concentrations. The BPKS hinged TKA showed significantly lower metal ion concentrations compared with the GenuX TKA. No benefits were observed using TiN coating. The different weightbearing mechanics might influence the wear of the component materials. Higher workloads and physical activity could influence chromium levels. Cite this article: Bone Joint J 2022;104-B(3):376–385

Introduction. Recent studies of novel healthcare episode payment models, such as the Bundled Payments for Care Improvement (BPCI) initiative, have demonstrated pathways for improving value. However, these models may not provide appropriate payments for patients with significant medical comorbidities or complications. The objective of this study was to identify risk factors for exceeding our institution's target payment, the so-called “bundle busters.”. Methods. After receiving an exemption from the Institutional Review Board, we queried our institutional data warehouse for all patients (n=412) that underwent total joint arthroplasty (TJA) of the hip (n=192), knee (n=207), or ankle (n=13), and qualified for our institution's bundled payments model during the study time period (July 2015 – May 2017). Patients with medical conditions that were not well controlled or were potentially optimizable were all sent for preoperative medical optimization prior to surgery. For each 90-day episode, patient characteristics, medical comorbidities, perioperative data, and payments from the Centers for Medicare and Medicaid Services (CMS) were obtained. Episodes where Medicare payments exceeded the target payment were considered “busters”. The busters were older, and had higher comorbidity scores (all, p<0.01). Variables were summarized using descriptive statistics and risk ratios were calculated using a modified Poisson regression analysis. Results. Of the 412 patients, 123 were bundle busters (30%). There was a median institutional loss of $11,797 (IQR, $4,312 – $26,771) for the bundle busters and a median gain of $7,402 ($5,657 – $9,206) for the non-busters. Of the 32 risk factors evaluated, 11 were identified as Independent risk factors for busting the bundle (all, p<0.05). Nine of the 11 (82%) are non-modifiable risk factors and include age, disease specific diagnoses (fracture and avascular necrosis), and medical comorbidities (congestive heart failure, pulmonary circulation disorders, renal disease, cardiac arrhythmia, chronic pulmonary disease, and neurological disorder). The remaining two medical comorbidities are potentially modifiable and include diabetes with complications, and preoperative anemia. Conclusion. Though modifiable risk factors should continue to be optimized prior to TJA, as they were in this population, there are still many non-modifiable preoperative risk factors that can lead to costs exceeding the BPCI established institutional payment goal. As such, further work with payors may be needed to help fairly and appropriately consider these non-modifiable factors which result in increased costs

Aims. The aim of this study was to compare ten-year longitudinal healthcare costs and revision rates for patients undergoing unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA). Methods. The Humana database was used to compare 2,383 patients undergoing UKA between 2007 and 2009, who were matched 1:1 from a cohort of 63,036 patients undergoing primary TKA based on age, sex, and Elixhauser Comorbidity Index. Medical and surgical complications were tracked longitudinally for one year following surgery. Rates of revision surgery and cumulative mean healthcare costs were recorded for this period of time and compared between the cohorts. Results. Patients undergoing TKA had significantly higher rates of manipulation under anaesthesia (3.9% vs 0.9%; p < 0.001), deep vein thrombosis (5.0% vs 3.1%; p < 0.001), pulmonary embolism (1.5% vs 0.8%; p = 0.001), and renal failure (4.2% vs 2.2%; p < 0.001). Revision rates, however, were significantly higher for UKA at five years (6.0% vs 4.2%; p = 0.007) and ten years postoperatively (6.5% vs 4.4%; p = 0.002). Longitudinal-related healthcare costs for patients undergoing TKA were greater than for those undergoing UKA at one year ($24,771 vs $22,071; p < 0.001) and five years following surgery ($26,549 vs $25,730; p < 0.001); however, the mean costs of TKA were comparable to UKA at ten years ($26,877 vs $26,891; p = 0.425). Conclusion. Despite higher revision rates, patients undergoing UKA had lower mean healthcare costs than those undergoing TKA up to ten years following the procedure, at which time costs were comparable. In the era of value-based care, surgeons and policymakers should be aware of the costs involved with these procedures. UKA was associated with fewer complications at one year postoperatively but higher revision rates at five and ten years. While UKA was significantly less costly than TKA at one and five years, costs at ten years were comparable with a mean difference of only $14. Lowering the risk of revision surgery should be targeted as a source of cost savings for both UKA and TKA as the mean related healthcare costs were 2.5-fold higher in patients requiring revision surgery. Cite this article: Bone Joint J 2021;103-B(6 Supple A):23–31

Aims. While patients with psychological distress have poorer short-term outcomes after total knee arthroplasty (TKA), their longer-term function is unknown. We aimed to 1) assess the influence of preoperative mental health status on long-term functional outcomes, quality of life, and patient satisfaction; and 2) analyze the change in mental health after TKA, in a cohort of patients with no history of mental health disorder, with a minimum of ten years’ follow-up. Methods. Prospectively collected data of 122 patients undergoing primary unilateral TKA in 2006 were reviewed. Patients were assessed pre- and postoperatively at two and ten years using the Knee Society Knee Score (KSKS) and Function Score (KSFS); Oxford Knee Score (OKS); and the Mental (MCS) and Physical Component Summary (PCS) which were derived from the 36-Item Short-Form Health Survey questionnaire (SF-36). Patients were stratified into those with psychological distress (MCS < 50, n = 51) and those without (MCS ≥ 50, n = 71). Multiple regression was used to control for age, sex, BMI, Charlson Comorbidity Index (CCI), and baseline scores. The rate of expectation fulfilment and satisfaction was compared between patients with low and high MCS. Results. There was no difference in the mean KSKS, KSFS, OKS, and SF-36 PCS at two years or ten years after TKA. Equal proportions of patients in each group attained the minimal clinically important difference for each score. Psychologically distressed patients had a comparable rate of satisfaction (91.8% (47/51) vs 97.1% (69/71); p = 0.193) and fulfilment of expectations (89.8% vs 97.1%; p = 0.094). The proportion of distressed patients declined from 41.8% preoperatively to 29.8% at final follow-up (p = 0.021), and their mean SF-36 MCS improved by 10.4 points (p < 0.001). Conclusion. Patients with poor mental health undergoing TKA may experience long-term improvements in function and quality of life that are comparable to those experienced by their non-distressed counterparts. These patients also achieved a similar rate of satisfaction and expectation fulfilment. Undergoing TKA was associated with improvements in mental health in distressed patients, although this effect may be due to residual confounding. Cite this article: Bone Joint J 2020;102-B(7):845–851

Aims. The Bundled Payments for Care Improvement (BPCI) initiative has identified pathways for improving the value of care. However, patient-specific modifiable and non-modifiable risk factors may increase costs beyond the target payment. We sought to identify risk factors for exceeding our institution’s target payment, the so-called ‘bundle busters’. Patients and Methods. Using our data warehouse and Centers for Medicare and Medicaid Services (CMS) data we identified all 412 patients who underwent total joint arthroplasty and qualified for our institution’s BPCI model, between July 2015 and May 2017. Episodes where CMS payments exceeded the target payment were considered ‘busters’ (n = 123). Risk ratios (RRs) were calculated using a modified Poisson regression analysis. Results. An increased risk of exceeding the target payment was significantly associated with increasing age (adjusted RR 1.04, 95% confidence interval (CI) 1.01 to 1.06) and body mass index (adjusted RR 1.03, 95% CI 1.003 to 1.06). Eight comorbid risk factors were also identified (all p < 0.05), only two of which were considered to be potentially modifiable (diabetes with complications and preoperative anaemia). An American Society of Anesthesiologist physical status classification system (ASA) score ≥ 3 (adjusted RR 2.3, 95% CI 1.67 to 3.18) and Charlson Comorbidity Index (CCI) ≥ 3 (adjusted RR 1.94, 95% CI 1.45 to 2.60) were risk factors for bundle busting. Conclusion. Non-modifiable preoperative risk factors can increase costs and exceed the target payment. Future bundled payment models should incorporate the stratification of risk. Cite this article: Bone Joint J 2019;101-B(7 Supple C):64–69

Introduction. Total Knee Arthroplasty (TKA) in high risk patients may result in numerous post-operative complications that may ultimately lead to above knee amputation (AKA). There is a paucity of literature regarding AKA in patients with prior TKA. We sought to characterize the factors leading to AKA, as well as patient functional and clinical outcomes post-operatively, with the hypothesis that minimal activity would be achieved. Methods. This is a multicenter retrospective review for patient identification, with prospective telephone survey completion for assessment of functional status. All patients from January 2001 to December 2015 with AKA and prior TKA at two academic centers were included for possible survey enrollment. Demographic information and medical comorbidities were collected, in addition to perioperative and post-operative mortality data. A 23-item survey was provided to all available patients and analyzed for patient functional status. Results. 112 patients with AKA following TKA were included for analysis with mean age 60.6 (11.5) years at TKA, with 3.7 (3.14) surgeries over 6.0 (6.3) years prior to AKA. The most common medical comorbidities were cardiac disease (64.3%), renal insufficiency (34.8%), and atherosclerosis (26.8%). Indications for AKA were multifactorial, however, were primarily driven by infection (87.5%) and vascular disease (10.7%). At the time of the survey, 49 (43.8%) patients were deceased and the 5-year survival rate was 60.2% (figure I). 34 (30.4%) patients were enrolled for survey completion. Of the respondents, 32 (94.1%) reported owning a prosthesis but only 19 (55.9%) reported wearing it, and 19 (55.9%) primarily used a wheelchair for mobility. 27 (79.5%) noted phantom pain with 16 (47.1%) requiring chronic medication. Overall, only 18 patients (52.9%) were satisfied with their quality of life. Discussion and Conclusion. TKA patients often undergo multiple surgeries over many years prior to AKA. Following this procedure, there is a high mortality rate; for patients surviving, almost half are dissatisfied with their quality of life, and low functional status is observed. TKA patients that might be considered candidates for AKA should be made aware the expected clinical and functional outcomes. For any figures or tables, please contact authors directly

Aims. The outcomes of total knee arthroplasty (TKA) depend on many factors. The impact of implant design on patient-reported outcomes is unknown. Our goal was to evaluate the patient-reported outcomes and satisfaction after primary TKA in patients with osteoarthritis undergoing primary TKA using five different brands of posterior-stabilized implant. Patients and Methods. Using our institutional registry, we identified 4135 patients who underwent TKA using one of the five most common brands of implant. These included Biomet Vanguard (Zimmer Biomet, Warsaw, Indiana) in 211 patients, DePuy/Johnson & Johnson Sigma (DePuy Synthes, Raynham, Massachusetts) in 222, Exactech Optetrak Logic (Exactech, Gainesville, Florida) in 1508, Smith & Nephew Genesis II (Smith & Nephew, London, United Kingdom) in 1415, and Zimmer NexGen (Zimmer Biomet) in 779 patients. Patients were evaluated preoperatively using the Knee Injury and Osteoarthritis Outcome Score (KOOS), Lower Extremity Activity Scale (LEAS), and 12-Item Short-Form Health Survey questionnaire (SF-12). Demographics including age, body mass index, Charlson Comorbidity Index, American Society of Anethesiologists status, sex, and smoking status were collected. Postoperatively, two-year KOOS, LEAS, SF-12, and satisfaction scores were compared between groups. Results. Outcomes were available for 4069 patients (98%) at two years postoperatively. In multiple regression analysis, which separately compared each implant group with the aggregate of all others, there were no clinically significant differences in the change of KOOS score from baseline to two-year follow-up between any of the groups. More than 80% of patients in each group were satisfied at this time in all domains. In a multivariate regression model, patients in the NexGen group were the most likely to be satisfied (odds ratio (OR) 1.63; p = 0.006) and Optetrak Logic patients were the least likely to be satisfied (OR 0.60; p < 0.001). Conclusion. TKA provides improvement in function and satisfaction regardless of the type of implant. We could not demonstrate superiority of one design above others across these groups of implants, and any price premium for one above the other systems may not be justified. Healthcare administrators may find these similarities in outcomes helpful when negotiating purchasing contracts. Cite this article: Bone Joint J 2019;101-B(7 Supple C):48–54

Aims. This study investigated the influence of body mass index (BMI) on patients’ function and quality of life ten years after total knee arthroplasty (TKA). Patients and Methods. A total of 126 patients who underwent unilateral TKA in 2006 were prospectively included in this retrospective study. They were categorized into two groups based on BMI: < 30 kg/m. 2. (control) and ≥ 30 kg/m. 2. (obese). Functional outcome was assessed using the Knee Society Function Score (KSFS), Knee Society Knee Score (KSKS), and Oxford Knee Score (OKS). Quality of life was assessed using the Physical (PCS) and Mental Component Scores (MCS) of the 36-Item Short-Form Health Survey. Results. Patients in the obese group underwent TKA at a younger age (mean, 63.0 years, . sd. 8.0) compared with the control group (mean, 65.6 years, . sd. 7.6; p = 0.03). Preoperatively, both groups had comparable functional and quality-of-life scores. Ten years postoperatively, the control group had significantly higher OKS and MCS compared with the obese group (OKS, mean 18 (. sd. 5) vs mean 22 (. sd. 10), p = 0.03; MCS, mean 56 (. sd. 10) vs mean 50 (. sd. 11), p = 0.01). After applying multiple linear regression with the various outcomes scores as dependent variables and age, gender, and Charlson Comorbidity Index as independent variables, there was a clear association between obesity and poorer outcome in KSFS, OKS, and MCS at ten years postoperatively (p < 0.01 in both KSFS and OKS, and p = 0.03 in MCS). Both groups had a high satisfaction rate (97.8% in the control groupvs 87.9% in the obese group, p = 0.11) and fulfillment of expectations at ten years (98.9% in the control group vs 100% in the obese group, p = 0.32). Conclusion. Although both obese and non-obese patients have significant improvements in function and quality of life postoperatively, obese patients tend to have smaller improvements in the OKS and MCS ten years postoperatively. It is important to counsel patients on the importance of weight management to achieve a more sustained outcome after TKA. Cite this article: Bone Joint J 2018;100-B:579–83

At our tertiary, large, academic healthcare system, we have access to an academic medical center (AMC), a community based, orthopedic friendly, efficient hospital (CBH) and several ambulatory care centers (ASC) which are being prepared to provide same day discharge (SDD) TJA and UKA. We had a near-capacity AMC with an excellent ability to care for medically and technically complicated TJA patients. However, efficiency was less than desired regardless of case complexity with an average effective case time of 4 hours. Concurrently, the orthopaedically, under-utilized community-based hospital (CBH) wanted to increase volume, improve margins, and become a TJA Center of Excellence with the ability to provide an efficient Hospital Outpatient Department (HOPD) and SDD TJA surgery experience. Methods. The CBH had a main operating floor and a separate floor of four OR suites which were repurposed with the goal of utilizing these rooms for TJA four days per week with an average of 3.5 cases per room per day. We preferentially performed primary, uncomplicated TJA, UKA, and minimally invasive TJA at the CBH. Revision surgeries, patients with extensive medical comorbidities, and complex primary surgeries would be performed at the AMC. Our goals were to decrease costs, readmissions, length of stay, and increase margins at the CBH while increasing efficiency, revenue and volume. Protocols were developed to facilitate SDD UKA and THA at both hospitals as well as rapid recovery protocols for TKA at both hospitals with the understanding that the CBH would perform more of these cases but the efficiency could also be implemented at the AMC when possible. We also needed a strategy to deal with TKA and eventually THA being removed from the Inpatient Only (IPO) list. CMS has utilized the “Two-Midnight Rule” to define outpatient status for both THA and TKA. This has distinct financial implications for the facility's reimbursement with outpatient being $10,123 on average versus $12,380 for inpatient status. A protocol-based system was put in place to make both hospitals compliant with the removal of TKA from the IPO List in order to avoid Quality Improvement Organization (QIO) and Recovery Audit Contractor (RAC) after implementation. Results. Comparing FY 2018 to FY 2019, volume increased 26.4% at the CBH. Outpatient case volume rose substantially from 14 cases to 243. Volumes were slightly decreased at the AMC (−4.57%) resulting in a substantial increase in margin contribution for the parent enterprise. Quality metrics at the CBH (surgical site infections (SSI), length of stay (LOS), readmissions, and mortality) were improved. LOS improved from 52% to 71% discharge before 48 hours. The LOS decreased 12% for THA and 8.1% for TKA. CBH readmission rates decreased from 1.38% to 0.9% with no deaths. Surgeon satisfaction is greatly improved as their volume, efficiency, quality metrics, and finances were enhanced. Financial performance was improved in aggregate and per case for the CBH. Although the CBH per-case revenue was 80.3% and 74.4% of the AMC for THA and TKA: the net margins were 3.6% and 18.8% higher for THA and TKA, respectively. The increased efficiency, lower hospital cost and higher volume at the CBH allowed for an increase in revenue despite lower reimbursement per case. Conclusions. A shifting reimbursement landscape, value-based payment initiatives, and increasing volume have challenged traditional TJA delivery systems. This demonstrates one strategy to help hospital systems improve net margins while improving patient care despite lower net revenue per TJA episode. These strategies will become increasingly important going forward with the transition of higher numbers of TJA patients to outpatient settings including ambulatory surgery centers which will be subjected to even further decreases in net revenue per patient

Aims

The purpose of this study was to assess mid-term survivorship following primary total knee arthroplasty (TKA) with Optetrak Logic components and identify the most common revision indications at a single institution.

Introduction. As total knee arthroplasty incidence in the United States continues to increase, health care entities are looking to reform policy to decrease costs while improving efficiency and quality of care. The allocation of hospital and surgeon charges and payments is an important aspect of health care economics, but the trends and relationship between surgeon and hospital charges and payments for knee arthroplasty have not been well examined. The goal of this study is to report trends and variation in hospital charges and payments compared to surgeon charges and payments for total knee arthroplasty in a Medicare population. Methods. The 5% Medicare sample was used to capture hospital and surgeon charges and payments for total knee arthroplasty from 2005–2014. Two important values were calculated: (1) the charge multiplier (CM) which is the ratio of hospital to surgeon charges, and (2) the payment multiplier (PM), which is the ratio of hospital to surgeon payments. The year to year variation and regional trends in patient demographics, Charlson Comorbidity Index (CCI), length of stay (LOS), CM and PM were evaluated for all patients. Statistical significance of trends was evaluated using student's t-tests. Correlations between the financial multipliers and LOS were evaluated using a Pearson correlation coefficient (r). Results. 117,698 patients were included. Hospital charges were significantly higher than surgeon charges throughout the study period and increased substantially (CM increased from 7.9 to 11.4, p <0.0001) [Fig 1,2]. Hospital payments relative to surgeon payments ratio (PM) followed a similar trend, increasing from 10.0 to 14.6 (p < 0.0001). [Fig 1,2]. Similar trends were noted in all four regions of the US. LOS decreased significantly throughout the study from 3.8 to 2.8 days (p < 0.0001). CCI remained stable over the study period. Both the CM (r2 = −0.90) and PM (r2 = −0.84) were strongly negatively associated with LOS, meaning that as LOS decreased, the ratio of hospital to surgeon charges and payments (CM and PM) paradoxically significantly increased [Fig 3]. Conclusions. Hospital charges and payments relative to surgeon charges and payments have significantly increased for total knee arthroplasty despite stable patient complexity as measured by CCI and decreasing LOS. These results encourage the need for future studies with detailed cost analysis to identify the causes of hospital and surgeon financial malalignment. As healthcare shifts toward value-based care with shared responsibility for outcomes and cost, more closely aligned incentives between hospitals and providers is needed. For figures, tables, or references, please contact authors directly

Aims

Patient dissatisfaction following primary total knee arthroplasty (TKA) with manual jig-based instruments has been reported to be as high as 30%. Robotic-assisted total knee arthroplasty (RA-TKA) has been increasingly used in an effort to improve patient outcomes, however there is a paucity of literature examining patient satisfaction after RA-TKA. This study aims to identify the incidence of patients who were not satisfied following RA-TKA and to determine factors associated with higher levels of dissatisfaction.

Aims. The aim of this study was to characterize the factors leading to transfemoral amputation after total knee arthroplasty (TKA), as well as the rates of mortality and functional independence after this procedure in these patients. Patients and Methods. This was a multicentre retrospective review with a prospective telephone survey for the assessment of function. All patients with a TKA who subsequently required transfemoral amputation between January 2001 and December 2015 were included. Demographic information, medical comorbidities, and postoperative mortality data were collected. A 19-item survey was used for the assessment of function in surviving patients. Results. A total of 111 patients were included. Their mean age was 61.0 years (42.0 to 88.0) at the time of TKA, with a subsequent mean of 3.7 operations (0 to 15) over a mean period of 6.1 years (0.05 to 30.1) before amputation. The indication for amputation was chronic infection in 97 patients (87.4%). The rate of five-year survival was 51.7%, and advanced age (p = 0.001) and renal failure (p = 0.045) were associated with an increased risk of mortality. Of the 62 surviving patients, 34 completed the survey; 32 (94.1%) owned a prosthesis but only 19 (55.9%) used it; 19 (55.9%) primarily used a wheelchair for mobility; 27 (79.5%) had phantom pain; and 16 (47.1%) required chronic pain medication. Only 18 patients (52.9%) were satisfied with the quality of life. Conclusion. Patients with complications after TKA, in whom transfemoral amputation is considered, should be made aware of the high rate of mortality and the poor functional outcome in the survivors. Alternative forms of treatment including arthrodesis of the knee should be investigated

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In cases of severe periprosthetic joint infection (PJI) of the knee, salvage procedures such as knee arthrodesis (KA) or above-knee amputation (AKA) must be considered. As both treatments result in limitations in quality of life (QoL), we aimed to compare outcomes and factors influencing complication rates, mortality, and mobility.

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The aim of this study was to assess factors associated with the estimated lifetime risk of revision surgery after primary knee arthroplasty (KA).

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The aim of this study was to describe the pattern of revision indications for unicompartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA) and any change to this pattern for UKA patients over the last 20 years, and to investigate potential associations to changes in surgical practice over time.

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Periprosthetic fractures (PPFs) around the knee are challenging injuries. This study aims to describe the characteristics of knee PPFs and the impact of patient demographics, fracture types, and management modalities on in-hospital mortality.

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This study aims to determine the rate of and risk factors for total knee arthroplasty (TKA) after operative management of tibial plateau fractures (TPFs) in older adults.