Introduction. Pressure to control health care costs may limit the ability of new implants to enter the market. Customized individually made (CIM) knee implants are produced from CT scans of each patient and may result in improved clinical outcomes based on early data showing less blood loss, reduced bone resection, and better implant function and alignment. Limited economic evidence suggests that the use of CIM technology may result in cost savings, particularly when post-discharge expenses are included. The purpose of this study was to evaluate real-world cost data to determine episode spending in a Medicare population receiving either CIM or off-the-shelf (OTS) implants. Methods. The Yale Center for Musculoskeletal Care and Baker Tilly Healthcare Management reviewed episode expenditures among Medicare beneficiaries who received CIM and OTS implants for TKA between 01/01/2015 and 12/31/2015. Episode costs included the pre-operative CT scan, index TKA procedure, and 12-month post-index spending for inpatient (IP), outpatient (OP), emergency room (ER), skilled nursing facility (SNF), and home health (HH) services. CIM patients were identified through a matching process utilizing de-identified patient demographic and procedural information and the presence of a CT scan 28–365 days before index. OTS patients included those without a CT scan within one year of index. CIM and OTS cohorts were propensity matched to produce comparable cohorts at a one-to-five ratio based on age range, gender, race, geographical location, and comorbidities. Average expenditure was used to calculate one-year costs of care differences between the CIM and the OTS technologies. A Generalized Linear Model (GLM) and two-part model (logistics and GLM) were used to test statistical significance. Results. The study included 4,434 patients (CIM: 739, OTS: 3,695). CIM index hospital expenses were 6.5% less than OTS (CIM: $11,579; OTS: $12,386, p<0.0001). CIM patients were 37.5% less likely to incur SNF costs than OTS patients (CIM: 3.0% vs. OTS: 4.8%; p=0.0241) and had 45.1% lower average SNF expenditures (CIM: $8,882 vs. OTS: $16,183; p=0.0236). There was no difference in the probability of incurring post-index IP costs (CIM: 15.7% vs. OTS: 15.4%; p=0.9437) but average post-index IP expenditures were 27.2% lower among the CIM cohort than OTS (CIM: $12,817 vs. OTS: $17,605; p=0.0008). However, CIM patients were 10.5% more likely to incur OP costs (CIM: 90.9% vs. OTS: 85.7%; p=0.0005) and had 6.1% higher average OP expenditures (CIM: $2,328 vs. OTS: $2,106; p=0.0377). Average 12-month episode spending for the CIM cohort was 8.4% less than the OTS cohort ($1,697 Difference; CIM: $18,585 vs. OTS: $20,280; p<0.0001). Conclusion. Study findings demonstrate that the use of CIM technology can result in significant 12-month episode savings among a Medicare population. The average expenditure differences noted for post-index IP, SNF, and OP cost categories suggest there are differences in required post-operative treatment across the two cohorts. Savings calculated in the analysis is a meaningful reduction for payers. Providers may also benefit from index and episode cost savings through shared savings arrangements. CIM technology should be considered as a method to reduce TKA episode spending

Abstract. Introduction. Uni-compartmental knee replacement (UKR) has become popularised due to quicker recovery times, reduced postoperative pain, and blood loss. The desire to increase bed capacity and reduce costs, while preserving safety and patient satisfaction, has led to increased interest in day-case arthroplasty. This study observes the feasibility of UKR as a day-case procedure and whether this affects short and long-term postoperative outcomes. Methodology. Between 2018 and 2021, at a single institution and operated by a single orthopaedic surgeon, seventy-seven patients received a UKR on an elective basis. The patients were divided into two groups: ‘day-case’ for those discharged on the same day, and ‘non day-case’ group. Results. 31 patients were identified as day case procedures with the remaining 46 requiring between one to three days before discharge. Mean age, sex, modal ASA score, BMI, Charlson co-morbidity index, and pre-op oxford knee score showed no statistically significant difference between the two groups (p>0.05). No significant difference between the post-op oxford knee score at 1 year was found for patients treated and discharged as a day case procedure (37.8 +/− 6.88) and those who remained as an inpatient postoperatively (37.8 +/− 10.7); t(df) = −0.0007, p=0.994. No patients in either group suffered any complications beyond the peri-operative period. 30-day and 90-day readmission rates were equal. Conclusions. With no significant differences in post-op knee scores, complication, and readmission rates, we feel UKR can be performed as a viable day case procedure in a planned elective setting. This will result in significant cost savings

Abstract. Background. Daycase pathways which aim to discharge patients the same day following Unicompartmental Knee Replacement have been introduced in some centres, though most continue with Standard pathways. While Daycase pathways have cost savings, recovery data comparing pathways is limited. This study aims to compare patient-reported early recovery between Daycase and Standard pathways following UKR. Method. This study was carried out in two centres that originally used the same Standard recovery pathway for UKR. In one centre, the Standard pathway was modified into a Daycase pathway. 26 Daycase-Outpatient, 11 Daycase-Inpatient, and 18 Standard patients were recruited. Patients completed the Oxford Arthroplasty Early Recovery Score (OARS) and SF-36 (Acute) measure between Days 1–42. Results. Standard patients had significantly better Day-1 scores than Daycase patients, but this difference rapidly diminished, and from Day-3 onwards both groups had near-identical scores (OARS Day-1, 59 vs 37, p=0.002, stemming from differences in Pain, Nausea/Feeling-Unwell, Function/Mobility subscores p=0.003,0.014,0.011. OARS Day-3 48 vs 49, p=0.790). Daycase-Outpatients had a higher overall OARS (p=0.002), recovering 1–2 weeks faster than Daycase-Inpatients. OARS subscores demonstrated that Daycase-Outpatients had better Pain, Nausea/Feeling-Unwell, Fatigue/Sleep scores (p=0.020,0.0004,0.019 respectively). SF-36 scores corroborate OARS scores. Conclusion. The Standard cohort had better Day-1 scores than the Daycase cohort, likely due to later mobilisation and stronger inpatient analgesia; these differences diminished by Day-3. Daycase-Outpatients recovered substantially faster than Daycase-Inpatients – likely due to the factors that delayed their discharge. The convergence of scores at 6 weeks demonstrates that both pathways have similar early recovery outcomes

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

Patient specific instrumentation (PSI) uses advanced imaging of the knee (CT or MRI) to generate individualised cutting blocks aimed to make the procedure of total knee arthroplasty (TKA) more accurate and efficient. However, in this era of healthcare cost consciousness, the value of new technologies needs to be critically evaluated. There have been several comparative studies looking at PSI versus standard instrumentation. Most compare PSI with conventional instrumentation in terms of alignment in the coronal plane, operative time and surgical efficiency, cost effectiveness and short-term outcomes. Several systematic reviews and meta-analyses have also been published. PSI has not been shown to be superior compared with conventional instrumentation in its ability to restore traditional mechanical alignment in primary TKA. Most studies show comparative efficacy and no decrease in the number of outliers in either group. In terms of operative time and efficiency, PSI tended towards decreasing operative time, saving a mean of five minutes per patient (0 to 20). Furthermore, while some cost savings could be realised with less operative time and reduced instrumentation per patient, these savings were overcome by the cost of the CT/MRI and the cutting blocks. Finally, there was no evidence that PSI positively affected clinical outcomes at two days, two months, or two years. Consequently, current evidence does not support routine use of PSI in routine primary TKA. Cite this article: Bone Joint J 2016;98-B(1 Suppl A):78–80

Introduction. The purpose of bundled payment programs is to reduce cost via risk sharing, while still maintaining quality. If savings are achieved under a historic target price, the orthopedic surgeon will receive a monetary bonus. If costs are higher, a portion is deducted from payment to the orthopedic surgeon. The purpose of this study was to evaluate our experience with the Bundled Payments for Care Improvement Program (BPCI) when run by an orthopedic surgeon group to determine patient safety and who benefited the most financially. Methods. This program ran from January 2015 through September 2018. 3,186 Medicare total hip and knee replacements, elective (DRG 470) and for fracture (DRG 469), performed by our group were included. 90 day hospital and all postoperative expenditures were reconciled against our historic cost. All patients were medically optimized with discharge plans established preoperatively. We developed preferred skilled nursing facilities and home health care agencies with synergistic medical providers so that discharges were recommended as soon as appropriate. We hired two full-time case managers to have direct contact with patients pre-and post-operatively. Waiver assistance such as house and pet sitters were used if necessary at our expense. 35% of savings went to the convener, who acted as a liaison between our group and CMS. Expenditures for the 90-day period for all patients were calculated to determine where savings occurred and which entity benefitted financially. Results. There was an average 9.2% reduction in hospital readmissions. An estimated total savings of $5,100,000 occurred. There was a 17% reduction in hospital costs, a 12.1% reduction in admissions to skilled nursing facilities with a 34% reduction in length of stay, and a 5% reduction in admissions to inpatient rehabilitation facilities. There was a 35% reduction in home health visits, but no change in outpatient physical therapy visits. After group expenses, final bonus to the orthopedic provider was on average $262 per patient. Conclusion. The physician managed program was very successful from Medicare's standpoint, achieving significant monetary savings without reducing quality of care. However, the bonus to the providing and managing physicians was nominal. It also does not take into consideration the 50 plus hours spent in meetings to develop this program. Participation could be considered a defensive posture so as not to lose more reimbursement. However, experience was gained which will be valuable for future gain sharing programs. Physicians and physician organizations need to sit at the head of the table to manage future payment bundles and perhaps also act as the convener. We deserve this, as a result of demonstrating high safety and cost savings. For figures, tables, or references, please contact authors directly

Introduction. Robotic assisted Total Knee Arthroplasty (rTKA), provides surgeons with preoperative planning and real-time data allowing for continuous assessment of ligamentous tension and range-of-motion. Using this technology, soft tissue protection, reduced early post-operative pain and improved patient satisfaction have been shown. These advances have the potential to enhance surgical outcomes and may also reduce episode-of-care (EOC) costs for patients, payers, and hospitals. The purpose of this study was to compare robotic assisted vs. manual total knee arthroplasty: 1) 90-day episode-of-care (EOC) costs; 2) index costs; 3) lengths-of-stay (LOS); 4) discharge disposition; and 5) readmission rates. Methods. TKA procedures were identified using the Medicare 100% Standard Analytic Files including; Inpatient, Outpatient, Skilled Nursing (SNF) and Home Health. Members included patients with rTKA or manual TKA (mTKA) between 1/1/2016-3/31/2017. To account for potential baseline differences, propensity score matching (PSM) was performed in a 1-to-5 ratio, robotic to manual based on age, sex, race, geographic division, and comorbidities. After PSM, 519 rTKA and 2,595 mTKA were identified and included for analysis. Ninety-day episode-of-care cost, index cost, LOS, discharge disposition and readmission rates were assessed. Results. Overall 90-day EOC costs were $2,391 less for rTKA patients ($18,568 vs. $20,960; p<.0001). Index facility cost and LOS were also less for rTKA patients by $640 ($12,384 vs. $13,024; p=.0001) and 0.7 days (p<.0001). Additionally, rTKA patients were discharged to SNF less frequently (12.52% vs. 21.70%; p<.0001) and home with health aid (56.65% vs. 46.67%; p<.0001) or self-care (27.55% vs. 23.62%; p=.0566) more frequently and had a 90-day readmission reduction of 33% (p=.0423). Conclusion. Robotic assisted TKA resulted in an overall lower 90-day episode-of-care cost when compared to manual TKA. The 90-day EOC cost savings of rTKA were driven by reduced facility costs, LOS and readmissions, and an economically beneficial discharge destination

Introduction. Robotic-arm total knee arthroplasty (RTKA) was developed to potentially improve accuracy of bone cuts, component alignment, soft tissue balance, and patient outcomes. There is a paucity of data demonstrating that RTKA is superior to conventional total knee arthroplasty (CTKA) in terms of any of these metrics. This prospective comparative multicenter study was designed with these purposes in mind. Methods. Patients were enrolled between June 1st, 2016 and March 31st, 2018 in a prospective, non-randomized, open-label, multicenter, consecutive comparative cohort study comparing RTKA and CTKA. Only patients who satisfied the following inclusion criteria were included: body mass index (BMI) ≤ 40kg/m2, primary unilateral TKA procedure, at least 18 years of age, and no joint infection. The following data were collected for analysis:. Preoperative data on component size prediction from CT scans. Intraoperative data on bone resection levels and joint line maintenance. Functional activity scores, patient-reported symptoms, satisfaction and expectation scores using The New Knee Society Scoring System. Radiographic results, specifically coronal alignment. Results. For femoral components implanted, 82% were the exact size as predicted by the robotic-software and the remaining 18% were within 1 size (100% within 1 size). For tibial implants, 69% were the exact size of what the robotic-software predicted and 29% were within 1 size (98% within 1 size). RTKAs had significantly less distal lateral femoral resection (5.55 vs. 7.11 mm), distal medial femoral resection (6.89 vs. 7.97 mm), lateral tibial resection (7.76 vs. 8.54 mm), and medial tibial resection (4.11 vs. 5.56 mm, p<0.05) compared to CTKA. Joint line restoration was comparable between RTKA and CTKA, but required less tibial bone removal when using robotic techniques. Pre-operatively, all demographic, functional, symptom, satisfaction, and expectation measures were similar between treatment groups (all p<0.05, Tables 1–5). Those who underwent RTKA had significantly higher mean functional activity walking and standing score improvements from baseline to 4–6 weeks (1.4 vs. −1.2 points; p=0.019) and to 6 months (9.6 vs. 6.9 points; p=0.017) after surgery compared to CTKA. The mean overall functional activity score improvement from baseline to 1-year post-surgery was also higher for RTKA compared to CTKA (36.8 vs. 15.0 points; p=0.020). For all other parameters (standard activities, advanced activities, pain with walking, pain with stairs, satisfaction and expectation scores), score changes from baseline were not significantly different between groups, though many trended slightly higher for RTKA. Radiographic evaluation of RTKA demonstrated that varus deformity was corrected to neutral in 96% of cases and valgus deformity was corrected in 100%. Conclusion. To the best of our knowledge, this is the first study to prospectively evaluate outcomes of RTKA patients compared to CTKA. A number of positive early effects were seen with RTKA. This patient cohort will continue to be followed, and these findings may translate into longer-term patient reported outcomes improvement, longer component survivorship and cost savings. For any figures or tables, please contact authors directly

The statements contained in this document are solely those of the authors and do not necessarily reflect the views or policies of CMS. The authors assume responsibility for the accuracy and completeness of the information contained in this document. Background. The Bundled Payments for Care Improvement (BPCI) initiative was introduced to reduce healthcare costs while maintaining quality. We examined data from a healthcare system comprised of five hospitals that elected to participate in the BPCI Major Joint Replacement of the Lower Extremity Model 2 initiative beginning July 1, 2015. We compared one hospital that did 507 BPCI knee cases to the four other hospitals that did 566 cases. Stratifying the data by hospital volume, we sought to determine if costs decreased during the BPCI period, how the savings were achieved, and if savings resulted in financial rewards for participation. Methods. The Medicare data included the target cost for each episode (based on historical data from 2009–2012 for each hospital that was adjusted quarterly) and actual Part A and Part B spending for 90 days. Using 1,836 primary knee replacements, we analyzed the costs associated with the anchor hospitalization, inpatient rehabilitation, skilled nursing facilities, home health, outpatient physical therapy and readmission to compare the 1,073 knees done during the 16-month BPCI initiative period with the 763 knees done during the 1-year period preceding BPCI participation. Owing to the nonparametric distribution of the cost data, a Mann-Whitney U test was used to compare the higher volume hospital with the four lower volume hospitals. Results. Compared to the preceding year, the mean episode of care cost during BPCI participation decreased by 8.5% (from $20,853 to $19,087, p=0.24) at the higher volume hospital while remaining virtually unchanged (going from $20,383 to $20,380, p=0.10) at the lower volume hospitals. During the BPCI period, the mean Medicare 90-day target cost was $18,307 at the higher volume hospital and $22,287 at the lower volume hospitals (p<0.001). At the higher volume hospital, the major components of the savings included $367,290 from reduced readmission rates (5.7% versus 8.7%, p=0.11), $207,608 primarily due to a reduction in the length of stay at skilled nursing facilities (mean 15 days versus 25 days, p=0.005), and $130,894 associated with a decreased percentage of patients using inpatient rehabilitation (3.2% versus 4.9%, p=0.22). Although offset by other cost increases, the largest component of the savings at the lower volume hospitals was $262,548 due to a decrease in the percentage of patients (2.3% versus 4.8%, p=0.04) using inpatient rehabilitation. Despite its savings, the mean reconciliation penalty was $851 per case at the higher volume hospital while the lower volume hospitals received a mean reward of $2,165 per case. Conclusion. Based on the reduction in costs and decreased readmission rates, the BPCI initiative is achieving its objectives. Despite an 8.5% decrease in costs, the $18,307 target based on historical data resulted in an $851 penalty per case at the higher volume hospital. In contrast, as a result of a $3,980 higher target, the lower volume hospitals were rewarded even though they did not achieve cost savings. As structured, there is no incentive for centers with historically low costs to participate in BPCI

Introduction. Cementless total knees were historically associated with early failure. These failures, likely associated with implant design, made cemented total knee arthroplasty (TKA) the “gold standard”. Manufacturers have introduced newer uncemented technologies that provide good initial stability and utilize a highly-porous substrates for bony in-growth. Outcome data on these implants has been limited. In addition, these implants typically have a price premium which makes them difficult to use in the setting of cost containment and in at risk 90-day bundles. Our purpose was to compare 90-day outcomes of a new uncemented implant with those of a comparable cemented implant from the same manufacturer. We hypothesized that the implants would have equivalent 90-day clinical and economic outcomes. Methods. Ninety-day clinical and economic outcomes for 252 patients with prospectively collected data from the Michigan Arthroplasty Registry Collaborative Quality Initiative (MARCQI) database were reviewed. Ninety-day outcomes were compared between uncemented knees and an age-matched group of cemented knees (Triathlon cemented vs uncemented Triathalon-tritanium, Stryker Orthopedics, Mahwah, NJ, USA). Both cruciate retaining and posterior stabilized designs were included. MARCQI data: demographics, co-morbidities, length of stay, complications, emergency department visits, discharge disposition, and readmissions were reviewed. Financial data provided by the hospital's finance department was used for economic comparisons. Fischer's test was done to assess categorical data and a student's t-test was used to compare numerical data. Results. Uncemented knees had shorter length of stay (1.58 vs. 1.87, p<0.0001), were more frequently discharged home (90.48% vs. 68.75%; p<0.0001) and used less home care or extended care facilities (6.35% vs. 19.14%, p<0.0001; 2.78% vs. 11.72%, p=0.0001). More uncemented knees had “no complications”. Moreover, there were no reoperations in uncemented knees, compared to 19 reoperations in cemented knees most being manipulations (14 vs. 0, p=0.0028). Uncemented knees scored better than age matched counterparts Knee Injury and Osteoarthritis Outcomes Score (63.69 vs. 47.10, n=85 and 43, p<0.0001), and Patient Reported Outcomes Measurement Information System T-physical and T-mental (44.12 vs. 39.45, n=95 and 59, p<0.0001; 51.84 vs 47.82, n=97 and 59, p=0.0018). Cemented cases were more expensive overall, the surgical costs were higher ($6806.43 vs. $5710.78 p<0.01) and the total hospital costs were higher ($8347.65 vs. $7016.11 p<0.01). The 90-day readmission and hospital outpatient costs were not significantly different between the designs. Conclusion. The use of a modern uncemented TKA implants has increased, but data on outcomes and the economic impact has been limited particularly in regard to 90-day at risk global periods. Our study suggests that patients receiving an new uncemented TKA have a shorter length of stay, higher rate of discharge to home, better patient reported outcome measures, fewer complications and fewer reoperations than an age-matched group of patients receiving a similar, cemented design during the 90-day global period. Importantly, the uncemented knees had $1,095 less surgical episode costs (p< 0.001) and a 90-day cost savings of over $1,300 (p< 0.001). Uncemented TKA, when utilizing modern technologies, is successful and economically viable for an at-risk bundle. The results of this study should alleviate fears increased cost, early failure, complications or poor outcomes with the use of a modern uncemented TKA

Introduction. The Rapid Recovery Program (RRP) is a holistic perioperative accelerated discharge process that aims to improve efficiency and quality of care, improve patient education, standardise protocols and pathways and encourage early mobilisation & discharge. Aims. To compare length of stay (LOS) of primary knee arthroplasty patients before and after implementation of the RRP. Method. A retrospective cohort study of all patients admitted for knee arthroplasty was performed between 1. st. May 2007 and 28. th. February 2009. Data were obtained from hospital computer records. LOS of 2 groups compared: Pre-RRP implementation (Pre-RRP) and post-RRP implementation (post-RRP) and analysed using Welch's t- and chi square tests with significant at the p<0.05 level. (Definitions: Day of operation = ‘day 0’, first post-operative day = ‘day 1’, discharge = to the patient's own home). Results. 315 patients identified: 147 Pre-RRP (mean age 72 years; range 48-90) and 168 post-RRP (mean age 71 years; range 38-98). Mean LOS was reduced from 8.5 days (range 2-30) Pre-RRP to 5.9 days (range 2-38) post-RRP (p<0.01). Median LOS was reduced from 6 days (Pre-RRP) to 4 days (post-RRP) (p<0.01). Following RRP implementation, more patients were discharged on day 3 (Pre-RRP 9% vs Post RRP 30%; p<0.001) and less patients stayed more than 5 days (Pre-RRP 60% vs Post RRP 34%; p<0.001). Conclusion. The Rapid Recovery Programme significantly reduced LOS for knee arthroplasty patients, by a mean of 2.6 days. Significantly more patients were discharged by day 3 and significantly less stayed longer than 5 days. As well as cost savings, the patient experience was enhanced and the multidisciplinary team moral increased through centralised team work. Further evaluation of patient outcomes such as complication rates and patient satisfaction must be evaluated

Aims

Blood transfusion and postoperative anaemia are complications of total knee arthroplasty (TKA) that are associated with substantial healthcare costs, morbidity, and mortality. There are few data from large datasets on the risk factors for these complications.

Aims

The tibial component of total knee arthroplasty can either be an all-polyethylene (AP) implant or a metal-backed (MB) implant. This study aims to compare the five-year functional outcomes of AP tibial components to MB components in patients aged over 70 years. Secondary aims are to compare quality of life, implant survivorship, and cost-effectiveness.

Aims

To perform an incremental cost-utility analysis and assess the impact of differential costs and case volume on the cost-effectiveness of robotic arm-assisted unicompartmental knee arthroplasty (rUKA) compared to manual (mUKA).

The COVID-19 pandemic has led to unprecedented times worldwide. From lockdowns to masks now being part of our everyday routine, to the halting of elective surgeries, the virus has touched everyone and every part of our personal and professional lives. Perhaps, now more than ever, our ability to adapt, change and persevere is critical to our survival. This year's closed meeting of The Knee Society demonstrated exactly those characteristics. When it became evident that an in-person meeting would not be feasible, The Knee Society leadership, under the direction of President John Callaghan, MD and Program Chair Craig Della Valle, MD created a unique and engaging meeting held on September 10–12, 2020. Special recognition should be given to Olga Foley and Cynthia Garcia at The Knee Society for their flexibility and creativeness in putting together a world-class flawless virtual program. The Bone & Joint Journal is very pleased to partner with The Knee Society to once again publish the proceedings of the closed meeting of the Knee Society. The Knee Society is a United States based society of highly selected members who have shown leadership in education and research in knee surgery. It invites up to 15% international members; this includes some of the key opinion leaders in knee surgery from outside the USA. Each year, the top research papers from The Knee Society meeting will be published and made available to the wider orthopaedic community in The Bone & Joint Journal. The first such proceedings were published in BJJ in 2019. International dissemination should help to fulfil the mission and vision of the Knee Society of advancing the care of patients with knee disorders through leadership, education and research. The quality of dissemination that The Bone & Joint Journal provides should enhance the profile of this work and allow a larger body of surgeons, associated healthcare professionals and patients to benefit from the expertise of the members of The Knee Society. The meeting is one of the highlights of the annual academic calendar for knee surgeons. With nearly every member in attendance virtually throughout the 3 days, the top research papers from the membership were presented and discussed in a virtual format that allowed for lively interaction and discussion. There are 75 abstracts presented. More selective proceedings with full papers will be available after a robust peer review process in 2021, both online and in The Bone & Joint Journal. The meeting commenced with the first group of scientific papers focused on Periprosthetic Joint Infection. Dr Berry and colleagues from the Mayo Clinic further help to clarify the issue of serology and aspirate results to diagnose TKA PJI in the acute postoperative setting. 177 TKA's had an aspiration within 12 weeks and 22 were proven to have PJI. Their results demonstrated that acute PJI after TKA should be suspected within 6 weeks if CRP is ≥81 mg/L, synovial WBCs are ≥8500 cells/μL, and/or synovial neutrophils≥86%. Between 6– 12 weeks, concerning thresholds include a CRP ≥ 32 mg/L, synovial WBC ≥7450, and synovial neutrophils ≥ 84%. While historically the results of a DAIR procedure for PJI have been variable, Tom Fehring's study showed promise with the local delivery of vancomycin through the Intraosseous route improved early results. New member Simon Young contrasted the efficacy of the DAIR procedure when comparing early infections to late acute hematogenous PJI. DAIR failed in 63% of late hematogenous PJIs (implant age>1 year) compared to 36% of early (<1year) PJIs. Dr Masri demonstrated in a small group of patients that those with well-functioning articulating spacers can retain their spacers for over 12 months with no difference in infection from those that had a formal two stage exchange. The mental toll of PJI was demonstrated in a longitudinal study by Doug Dennis, where patient being treated with 2 stage exchange had 4x higher rates of depression compared to patient undergoing aseptic revision. The second session focused on both postoperative issues with regards to anticoagulation and manipulation. Steven Haas demonstrated high complication rates with utilization of anticoagulation for treatment of postoperative pulmonary embolism with modern therapeutic anticoagulation (warfarin, enoxaparin, Xa inhibitors) with the Xa inhibitors demonstrating lower complication rates. Two papers focused on the topic of manipulation. Mark Pagnano presented data on timing of manipulation under anesthesia up to even past 12 months. While gains were modest, a subset of patients did achieve substantial gains in ROM > 20degrees even after 3 months post op. Dr Westrich's study demonstrated no difference in MUA outcomes with either IV sedation or neuraxial anesthesia although the length of stay was shorter in the IV sedation group. Several studies in Session II focused on kinematics and femoral component position. Dr Li's in vivo kinematic study during weightbearing flexion and gait demonstrated that several knees rotated with a lateral pivot motion and not all knees can be described with a single motion character. Dr Mayman and his group utilized a computational knee model to demonstrate that additional distal femoral resection results in increasing levels of mid -flexion instability and cautioned against the use of additional bony resection as the first line for flexion contractures. Using computer navigation, Dr Huddleston's study nicely outlined the variability in femoral component rotation to achieve a rectangular flexion gap utilizing a gap balanced method. The third session opened the meeting on Friday morning. The focus was on unicompartmental knee arthroplasty and the increasing utilization of robotic assisted total knee arthroplasty. David Murray showed using registry data that for patient with higher comorbidities (ASA >3), UKA was safer and more cost effective than TKA while Dr Della Valle's group demonstrated overall lower average healthcare costs in UKA patients compared to TKA in the first 10 years after surgery. Dr Geller assessed UKA survivorship among 3 international registries. While survivorship varied by nation and designs, certain designs consistently had better overall performance. Dr Nunley and his group showed robotic navigation UKA significantly reduced outliers in alignment and overhang compared to manual UKA. Dr Catani's data demonstrated that full thickness cartilage loss should still be considered a requirement for UKA success even with robotic assistance. Despite a high dislocation rate of 4%, Mr Dodd demonstrated high survivorship for lateral UKA despite historical contraindications. The growing evidence for robotics TKA was demonstrated in two studies. Professor Haddad showed less soft tissue injury, reduced bone trauma and improved accuracy or rTKA compared to manual TKA while Dr Gustke single surgeon study showed his rTKA had improved forgotten joint scores and less ligament releasing required for balancing. Despite these finding, Dr Lee's study demonstrated that a robotic TKA could not guarantee excellent pain relief and other factors such a patient expectations and psychological factors play a role. Our fourth session was devoted to machine learning and smart tools and modeling. Dr Meneghini used machine learning algorithms to identify optimal alignment outcomes that correlated with patient outcomes. Several parameters such as native tibial slope, femoral sagittal position and coronal limb alignment correlated with outcomes. Along the same lines, Bozic and coauthors demonstrated that using AI algorithms incorporated with PROM's improved levels of shared decision making and patient satisfaction. Dr Lombardi demonstrated that a mobile patient engagement platform that provided smart phone-based exercise and education was comparable to traditional methods. Dr Mahfouz demonstrated the accuracy of using ultrasound to produce 3D models of the bone compared to conventional CT based strategies and Dr Mahoney showed the valued of a preop 3D model in reproducing more normal knee kinematics. The last two talks of the session focused on some of the positives of the COVID-19 pandemic, namely the embracing of telemedicine by patients and surgeons as demonstrated by Dr Slover and the increasing and far reaching educational opportunities made available to residents and fellows during the pandemic. Session five focused on risk stratification and optimization prior to TKA. Dr O'Connor demonstrated that that the implementation of an optimization program preoperatively reduced length of stay and ED visits, and Charles Nelson's study showed that risk stratification tool can lower complication rates in obese patients undergoing TKA comparable to those that are nonobese. Dr Markel's study demonstrated that those who have preoperative depression and anxiety are at higher risk of complications and readmissions after surgery and these issues should be addressed preoperatively. Interestingly, a study by Dr Callaghan demonstrated that care improvement pathways have not lowered the gap in complications for morbidly obese patients undergoing TKA, Dr Barsoum argued that the overall complication rates were low and this patient cohort had significant gains in PROMS after TKA that would not be experienced if arbitrary cutoff for limited surgery were established. The final session on Friday, Session six, had several well done and interesting studies. There continues to be mounting evidence that liposomal bupivacaine has little effect on managing post-operative pain to warrant its increased use. Bill Macaulay and colleagues showed no change in pain scores, opioid consumption and functional scores when liposomal bupivacaine was discontinued at a large academic medical center. Dr Bugbee importantly demonstrated that a supervised ambulation program reduced falls in the early postoperative period. Several paper on healthcare economics were presented. Rich Iorio showed that stratifying complexity of total joint cases between hospitals with a system can be efficient and cost savings while Dr Jiranek demonstrated in his study that complex TKAs can be identified preoperatively and are associated with prolonged operative time and cost of care and consideration should be given in future reimbursement models to a complexity modifier. Dr Springer, in their evaluation of Medicare bundled payment models, demonstrated that providers and hospitals in historical bundled models that became efficient were penalized in the new model, forcing many groups to drop out and return to a fee for service model. Ron Delanois important work showed that social determinants can have a major negative impact on outcomes following TKA. Our final day on Saturday opened with Session seven, and several interesting paper on metal ions/debris in TKA. Dr Whitesides simulator study showed the absence of scratches and material loss in a ceramic TKA compared with Co-Cr TKA and suggested an advantage to this material in patients with metal sensitivity. Conversely, in a histological study of failed TKA, perivascular lymphocytic infiltration was not associated with worse clinical outcomes or differences in revision in a series of 617 aseptic revisions, 19% of which had PVLI found on histology. The Mayo group and Dr Trousdale however, noted that serum metal ion levels can be helpful in identifying implant failure in a group of revision TKAs, especially those with metallic junctions. Dr Dalury demonstrated nicely that use of maximally conforming inserts did not have a negative effect on implant loosening in a series of 76 revision TKA's at an average follow up of 7 years, while Kevin Garvin and his group showed no difference in end of stem pain between cemented and cementless stems in revision TKA. The final two studies in the session by Bolognesi and Peters respectively showed that metaphyseal cones continue to demonstrate excelled survivorship in rTKA setting despite extensive bone loss. Session eight was highlighted by a large series of revision reported by new member Dr Schwarzkopf, who showed that revision TKA done by high volume surgeons demonstrated better outcomes and lower revision rates compared to surgeon who did less than 18 rTKA's per year. Dr Maniar importantly showed that preoperatively, patients with high activity level and low pain and indicated by a high preop forgotten joint score did poorly following TKA while David Ayers nicely demonstrated that KOOS scores that assess specific postoperative outcomes can predict patient dissatisfaction after TKA. The final paper in this session by Max Courtney showed that the majority of surgical cancellations are due to medical issues, yet a minority of these undergo any intervention specifically for that condition, but they resulted in a delay of 5 months. The first two studies of Session nine focused on polyethylene thickness. Dr Backstein demonstrated no difference in KSS scores, change in ROM and aseptic revision rates based on polyethylene thickness in a series of 195 TKA's. An interesting lab study by Dr Tim Wright showed a surprising consistency in liner thickness choice among varying levels of surgeon experience that did not correlate with applied forces or gap stability estimates. Two studies looked specifically at the issue of tibial loosening and implant design. Nam and colleagues were not able to demonstrate concerning findings for increasing tibial loosening in a tibial baseplate with a shortened tibial keel at short term follow up, while Lachiewicz demonstrated a 19% revision or revision pending rate in 223 cemented fixed bearing ATTUNE TKA at a mean of 30 months. Our final session of the meeting, began with encouraging news, that despite only currently capturing about 40% of TJA's done in the US, the American Joint Replacement Registry data is representative of data in other representative US databases. An interesting study presented by Robert Barrack looked at bone remodeling in the proximal tibia after cemented and cementless TKA of two different designs. No significant difference was noted among the groups with the exception of the cemented thicker cobalt chrome tray which demonstrated significantly more bone mineral density loss. Along the same lines, a study out of Dr Bostrom's lab demonstrated treatment of a murine tibial model with iPTH prevents fibrous tissue formation and enhances bone formation in cementless implants. New Member Jamie Howard showed no difference in implant migration and kinematics of a single radius cementless design using either a measured resection or gap balancing technique and Dr Cushner show no difference in blood loss with cemented or cementless TKA with the use of TKA. The final two studies looked at staging and bilateral TKA's. Peter Sharkey showed that simultaneous TKA's were associated with higher complication compared to staged TKA and that staged TKA with less than a 90-day interval was not associated with higher risk. However, Mark Figgie showed that patients undergoing simultaneous TKA compared to staged TKA, missed 17 fewer days of work. In spite of the virtual nature of the meeting, there were some outstanding scientific interactions and the material presented will continue to generate debate and to guide the direction of knee arthroplasty as we move forwards

Aims

In-hospital length of stay (LOS) and discharge dispositions following arthroplasty could act as surrogate measures for improvement in patient pathways, and have major cost saving implications for healthcare providers. With the ever-growing adoption of robotic technology in arthroplasty, it is imperative to evaluate its impact on LOS. The objectives of this study were to compare LOS and discharge dispositions following robotic arm-assisted total knee arthroplasty (RO TKA) and unicompartmental arthroplasty (RO UKA) versus conventional technique (CO TKA and UKA).

Aims

It has previously been shown that higher-volume hospitals have better outcomes following revision total knee arthroplasty (rTKA). We were unable to identify any studies which investigated the effect of surgeon volume on the outcome of rTKA. We sought to investigate whether patients of high-volume (HV) rTKA surgeons have better outcomes following this procedure compared with those of low-volume (LV) surgeons.

Aims

There is concern that aggressive target pricing in the new Bundled Payment for Care Improvement Advanced (BPCI-A) penalizes high-performing groups that had achieved low costs through prior experience in bundled payments. We hypothesize that this methodology incorporates unsustainable downward trends on Target Prices and will lead to groups opting out of BPCI Advanced in favour of a traditional fee for service.

Aims

Liposomal bupivacaine (LB) as part of a periarticular injection protocol continues to be a highly debated topic in total knee arthroplasty (TKA). We evaluated the effect of discontinuing the use of LB in a periarticular protocol on immediate postoperative pain scores, opioid consumption, and objective functional outcomes.

Aims

The COVID-19 pandemic led to a swift adoption of telehealth in orthopaedic surgery. This study aimed to analyze the satisfaction of patients and surgeons with the rapid expansion of telehealth at this time within the division of adult reconstructive surgery at a major urban academic tertiary hospital.