Dual Mobility Articulation in Revision Total Hip Arthroplasty: An American Joint Replacement Registry Analysis of Patients Aged 65 Years and Older.

BACKGROUND: Increasingly, dual mobility (DM) articulations have been used in revision total hip arthroplasty (THA), which may prevent postoperative hip instability. The purpose of this study was to report on outcomes of DM implants used in revision THA from the American Joint Replacement Registry (AJRR). METHODS: Revision THA cases performed between 2012 and 2018 Medicare were eligible and categorized by 3 articulations: DM, ≤32 mm, and ≥36 mm femoral heads. The AJRR-sourced revision THA cases were linked to Centers for Medicare and Medicaid Services (CMS) claims data to supplement (re)revision cases not captured in the AJRR. Patient and hospital characteristics were described and modeled as covariates. Using multivariable Cox proportional hazard models, considering competing risk of mortalities, hazard ratios were estimated for all-cause re-revision and re-revision for instability. Of 20,728 revision THAs, 3,043 (14.7%) received a DM, 6,565 (31.7%) a ≤32 mm head, and 11,120 (53.6%) a ≥36 mm head. RESULTS: At 8-year follow-up, the cumulative all-cause re-revision rate for ≤32 mm heads was 21.9% (95%-confidence interval (CI) 20.2%-23.7%) and significantly (P < .0001) higher than DM (16.5%, 95%-CI 15.0%-18.2%) and ≥36 mm heads (15.2%, 95%-CI 14.2%-16.3%). At 8-year follow-up, ≥36 heads had significantly (P < .0001) lower hazard of re-revision for instability (3.3%, 95%-CI 2.9%-3.7%) while the DM (5.4%, 95%-CI 4.5%-6.5%) and ≤32 mm groups (8.6%, 95%-CI 7.7%-9.6%) had higher rates. CONCLUSION: The DM bearings are associated with lower rates of revision for instability compared to patients who had ≤32 mm heads and higher revision rates for ≥36 mm heads. These results may be biased due to unidentified covariates associated with implant selection.

Risk Should Not Be a "Four-Letter Word" in Healthcare. Risk and the Future of Musculoskeletal Care.

Orthopaedics has seen a rapid transition to value-based care. As we transition away from fee-for-service models, healthcare systems, groups, and surgeons are being asked to take on an increasing amount of risk. While on the surface risk may have a negative connotation, managing risk allows surgeons to maintain autonomy while taking on value-based care to the next level. The purpose of this paper, the first in a series of 2, is to walk through the impact that value-based care has had on musculoskeletal surgeons, to understand the continued movement healthcare is making into risk sharing models, and to introduce the concept of surgeon specialist-led care.

A Specialist-Led Care Model: Aligning the Patient and Specialist for the Greatest Impact.

In the previous paper, discussing "Risk and the Future of Musculoskeletal Care," we reviewed the basic concepts of the risk corridor, implications on health care overall if we maintain a fee-for-service model, and the need for musculoskeletal specialists to begin taking on/managing risk to reinforce our presence in a "value-based care" system. This paper discusses the successes and failures of recent value-based care models and provides the framework for the paradigm of a specialist-led care model. We posit that orthopedic surgeons are the most knowledgeable physicians to manage musculoskeletal conditions, create new and innovative models, and lead value-based care to the next level.

Health Policy Views and Political Advocacy of Arthroplasty Surgeons: A Survey of the American Association of Hip and Knee Surgeons Members.

BACKGROUND: The American Association of Hip and Knee Surgeons (AAHKS) is the largest specialty society for arthroplasty surgeons in the United States and is dedicated to education, research, and advocacy. The purpose of this study was to identify the health policy views of AAHKS members and better characterize their advocacy participation. METHODS: A 22 question survey was electronically distributed multiple times via email link to all 3,638 United States members of AAHKS who were in practice or training in 2022. Study results were analyzed using descriptive statistics. RESULTS: There were 311 responses (9%), with 18% of respondents being within 5 years of practice and 38% having more than 20 years of practice. Respondents identified as Republicans (40%), Independents (37%), and Democrats (21%). Top policy issues included preserving physician reimbursement and equitable fee schedule representation (95%), the burden of prior authorization (53%), the impact of Center of Medicare and Medicaid Services regulations (39%), and medical liability and tort reform (39%). Members ranked maintaining appropriate physician reimbursement (44%) and advocating for patients (37%) as the top benefits to participation in advocacy. A majority of respondents (81%) stated that they spend more time on presurgery optimization now than 10 years ago. The most common barrier to advocacy participation was a lack of time (77%). CONCLUSION: Responding AAHKS members are well-informed, politically engaged, patient-oriented, and eager for a voice in policy decisions that affect the professional future of arthroplasty surgeons. These results can be used to help direct strategic efforts of the AAHKS Advocacy Committee to further increase advocacy efforts.

Effects of Hospital and Surgeon Volume on Patient Outcomes After Total Joint Arthroplasty: Reported From the American Joint Replacement Registry.

BACKGROUND: The purpose of this study was to evaluate outcomes and complications because it relates to surgeon and hospital volume for patients undergoing primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) using the American Joint Replacement Registry from 2012 to 2017. METHODS: A retrospective study was conducted on Medicare-eligible cases of primary elective THAs and TKAs reported to the American Joint Replacement Registry database and was linked with the available Centers of Medicaid and Medicare Services claims and the National Death Index data from 2012 to 2017. Surgeon and hospital volume were defined separately based on the median annual number of anatomic-specific total arthroplasty procedures performed on patients of any age per surgeon and per hospital. Values were aggregated into separate surgeon and hospital volume tertile groupings and combined to create pairwise comparison surgeon/hospital volume groupings for hip and knee. RESULTS: Adjusted multivariable logistic regression analysis found low surgeon/low hospital volume to have the greatest association with all-cause revisions after THA (odds ratio [OR], 1.63, 95% confidence interval [CI], 1.41-1.89, P < 0.0001) and TKA (OR, 1.72, 95% CI, 1.44-2.06, P < 0.0001), early revisions because of periprosthetic joint infection after THA (OR, 2.50, 95% CI, 1.53-3.15, P < 0.0001) and TKA (OR, 2.18, 95% CI, 1.64-2.89, P < 0.0001), risk of early THA instability and dislocation (OR, 2.47, 95% CI, 1.77-3.46, P < 0.0001), and 90-day mortality after THA (OR, 1.72, 95% CI, 1.27-2.35, P = 0.0005) and TKA (OR, 1.47, 95% CI, 1.15-1.86, P = 0.002). CONCLUSION: Our findings demonstrate considerably greater THA and TKA complications when performed at low-volume hospitals by low-volume surgeons. Given the data from previous literature including this study, a continued push through healthcare policies and healthcare systems is warranted to direct THA and TKA procedures to high-volume centers by high-volume surgeons because of the evident decrease in complications and considerable costs associated with all-cause revisions, periprosthetic joint infection, instability, and 90-day mortality. LEVEL OF EVIDENCE: III.

Cementless Fixation Is Associated With Increased Risk of Early and All-Time Revision After Hemiarthroplasty But Not After THA for Femoral Neck Fracture: Results From the American Joint Replacement Registry.

BACKGROUND: Despite ample evidence supporting cemented femoral fixation for both hemiarthroplasty and THA for surgical treatment of displaced femoral neck fractures, cementless fixation is the preferred fixation method in the United States. To our knowledge, no nationally representative registry from the United States has compared revision rates by fixation for this surgical treatment. QUESTION/PURPOSE: After controlling for relevant confounding variables, is femoral fixation method (cemented or cementless) in hemiarthroplasty or THA for femoral neck fracture associated with a greater risk of (1) all-cause revision or (2) revision for periprosthetic fracture? METHODS: Patients with Medicare insurance who had femoral neck fractures treated with hemiarthroplasty or THA reported in the American Joint Replacement Registry database from 2012 to 2017 and Centers for Medicare and Medicaid Services claims data from 2012 to 2017 were analyzed in this retrospective, large-database study. Of the 37,201 hemiarthroplasties, 42% (15,748) used cemented fixation and 58% (21,453) used cementless fixation. Of the 7732 THAs, 20% (1511) used cemented stem fixation and 80% (6221) used cementless stem fixation. For both the hemiarthroplasty and THA cohorts, most patients were women and had cementless femoral fixation. Early revision was defined as a procedure that occurred less than 90 days from the index procedure. All patients submitted to the registry were included in the analysis. Patient follow-up was limited to the study period. No patients were lost to follow-up. Due to inherent limitations with the registry, we did not compare medical complications, including deaths attributed directly to cemented fixation. A logistic regression model including the index arthroplasty, age, gender, stem fixation method, hospital size, hospital teaching affiliation, and Charlson comorbidity index score was used to determine associations between the index procedure and revision rates. RESULTS: For the hemiarthroplasty cohort, risk factors for any revision were cementless stem fixation (odds ratio 1.42 [95% confidence interval 1.20 to 1.68]; p < 0.001), younger age (OR 0.96 [95% CI 0.95 to 0.97]; p < 0.001), and higher Charlson comorbidity index (OR 1.06 [95% CI 1.02 to 1.11]; p = 0.004). Risk factors for early revision were cementless stem fixation (OR 1.77 [95% CI 1.43 to 2.20]; p < 0.001), younger age (OR 0.98 [95% CI 0.97 to 0.99]; p < 0.001), and higher Charlson comorbidity index (OR 1.09 [95% CI 1.04 to 1.15]; p < 0.001). Risk factors for revision due to periprosthetic fracture were cementless fixation (OR 6.19 [95% CI 3.08 to 12.42]; p < 0.001) and higher Charlson comorbidity index (OR 1.16 [95% CI 1.06 to 1.28]; p = 0.002). Risk factors for early revision due to periprosthetic fracture were cementless fixation (OR 7.38 [95% CI 3.17 to 17.17]; p < 0.001), major teaching hospital (OR 2.10 [95% CI 1.08 to 4.10]; p = 0.03), and higher Charlson comorbidity index (OR 1.20 [95% CI 1.09 to 1.33]; p < 0.001). For the THA cohort, there were no associations. CONCLUSION: These data suggest that cemented fixation should be the preferred technique for most patients with displaced femoral neck fractures treated with hemiarthroplasty. The fact that stem fixation method did not affect revision rates for those patients with displaced femoral neck fractures treated with THA may be due to current practice patterns in the United States. LEVEL OF EVIDENCE: Level III, therapeutic study.

Migration Patterns for Revision Total Knee Arthroplasty in the United States as Reported in the American Joint Replacement Registry.

BACKGROUND: Revision total knee arthroplasty (TKA) is associated with a higher complication rate and a greater cost when compared to primary TKA. Based on patient choice, referral, or patient transfers, revision TKAs are often performed in different institutions by different surgeons than the primary TKA. The aim of this study is to evaluate the effect of hospital size, teaching status, and revision indication on the migration patterns of failed primary TKA in patients 65 years of age and older. METHODS: All primary and revision TKAs reported to the American Joint Replacement Registry from January 2012 through March 2020 were included and merged with the Centers for Medicare and Medicaid Services database. Migration was defined as a patient having a primary TKA and revision TKA performed at separate institutions by different surgeons. RESULTS: In total, 9167 linked primary and revision TKAs were included in the analysis. Overall migration rates were significantly higher from small (<100 beds; P = .019), non-teaching institutions (P = .002) driven primarily by patients diagnosed with infection. Infection patients had significantly higher migration rates from small (46.8%, P < .001), non-teaching (43.5%, P < .001) institutions, while migration rates for other causes of revision were statistically similar. Most patients migrated to medium or large institutions (84.7%) for revision TKA rather than small institutions (15.3%, P < .001) and to teaching (78.3%) rather than non-teaching institutions (21.7%, P < .001). CONCLUSION: There is a diagnosis-dependent referral bias that affects the migration rates of infected primary TKA from small non-teaching institutions leading to a flow of more medically complex patients to medium and large teaching institutions for infected revision TKA.

Medicare bundles for arthroplasty : a journey back to fee for service?

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. METHODS: Using the Centers for Medicare and Medicaid Services (CMS) data, we compared the Target Price factors for hospitals and physician groups that participated in both BPCI Classic and BPCI Advanced (legacy groups), with groups that only participated in BPCI Advanced (non-legacy). With rebasing of Target Prices in 2020 and opportunity for participants to drop out, we compared retention rates of hospitals and physician groups enrolled at the onset of BPCI Advanced with current enrolment in 2020. RESULTS: At its peak in July 2015, 342 acute care hospitals and physician groups participated in Lower Extremity Joint Replacement (LEJR) in BPCI Classic. At its peak in March 2019, 534 acute care hospitals and physician groups participated in LEJR in BPCI Advanced. In January 2020, only 14.5% of legacy hospitals and physician groups opted to stay in BPCI Advanced for LEJR. Analysis of Target Price factors by legacy hospitals during both programmes demonstrates that participants in BPCI Classic received larger negative adjustments on the Target Price than non-legacy hospitals. CONCLUSION: BPCI Advanced provides little opportunity for a reduction in cost to offset a reduced Target Price for efficient providers, as made evident by the 85.5% withdrawal rate for BPCI Advanced. Efficient providers in BPCI Advanced are challenged by the programme's application of trend and efficiency factors that presumes their cost reduction can continue to decline at the same rate as non-efficient providers. It remains to be seen if reverting back to Medicare fee for service will support the same level of care and quality achieved in historical bundled payment programmes. Cite this article: Bone Joint J 2021;103-B(6 Supple A):119-125.

Adult Hip and Knee Reconstruction Education during the COVID-19 Pandemic.

BACKGROUND: The COVID-19 pandemic caused an abrupt disruption in residency and fellowship training, with most in-person teaching ceasing in March 2020. The AAHKS (American Association of Hip and Knee Surgeons) Board of Directors quickly initiated an online lecture series named the Fellows Online COVID-19 AAHKS Learning initiative. The purpose of this study is to illustrate the impact that this educational platform had on residents and adult hip and knee reconstruction fellows. METHODS: Between March 31, 2020 and June 25, 2020 an online educational platform was simultaneously developed and delivered. Adult hip and knee reconstruction fellows and residents were invited to participate in the free, live, online education sessions. Faculty from well-respected institutions from around the United States volunteered their time to host the initiative, choosing topics to present, ranging from hip (13 lectures) and knee (9 lectures), to practice management/miscellaneous (12 lectures). Attendee registrations were tracked via the online platform and the maximum number of attendees per session was recorded. A survey was administered to attendees for feedback. RESULTS: Thirty-four, 1-hour virtual lectures were delivered in real time by 79 different faculty members from 20 different institutions. A total of 4746 registrations for the 34 lectures were received, with 2768 registrants (58.3%) attending. The average attendance was 81 viewers per session (range 21-143), with attendance peaking mid-April 2020. A survey administered to lecture participants showed that 104/109 (95.4%) attended live lectures and 93/109 (85.3%) watched recorded sessions. About 92.5% of attendees responded that they wanted the lectures to continue after clinical responsibilities resumed. CONCLUSION: Amid a pandemic with cessation of in-person training, AAHKS delivered a robust virtual training alternative, exposing residents and fellows to a variety of renowned faculty and topics. Attendance with the program was very high, along with continued interest to continue this initiative. These worldwide lectures may lead to future opportunities in virtual residency and fellowship education.

Can an outpatient risk assessment tool predict who needs postoperative haemoglobin monitoring?

AIMS: Recent improvements in surgical technique and perioperative blood management after total joint replacement (TJR) have decreased rates of transfusion. However, as many surgeons transition to outpatient TJR, obtaining routine postoperative blood tests becomes more challenging. Therefore, we sought to determine if a preoperative outpatient assessment tool that stratifies patients based on numerous medical comorbidities could predict who required postoperative haemoglobin (Hb) measurement. METHODS: We performed a prospective study of consecutive unilateral primary total knee arthroplasties (TKAs) and total hip arthroplasties (THAs) performed at a single institution. Prospectively collected data included preoperative and postoperative Hb levels, need for blood transfusion, length of hospital stay, and Outpatient Arthroplasty Risk Assessment (OARA) score. RESULTS: A total of 504 patients met inclusion criteria. Mean age at time of arthroplasty was 65.3 years (SD 10.2). Of the patients, 216 (42.9%) were THAs and 288 (57.1%) were TKAs. Six patients required a blood transfusion postoperatively (1.19%). Transfusion after surgery was associated with lower postoperative day 1 Hb (median of 8.5 (interquartile range (IQR) 7.9 to 8.6) vs 11.3 (IQR 10.4 to 12.2); p < 0.001), longer length of stay (1 day (IQR 1 to 1) vs 2 days (IQR 2 to 3); p < 0.001), higher OARA score (median of 60.0 (IQR 40 to 75) vs 5.0 (IQR 0-35); p = 0.001), and total hip arthroplasty (p < 0.001). All patients who received a transfusion had an OARA score > 34; however, this did not reach statistical significance as a screening threshold. CONCLUSION: Risk of blood transfusion after primary TJR was uncommon in our series, with an incidence of 1.19%. Transfusion was associated with OARA scores > 60. The OARA score, not American Society of Anesthesiologists grade, reliably identified patients at risk for postoperative blood transfusion. Selective Hb monitoring may result in substantial cost savings in the era of cost containment. Cite this article: Bone Joint J 2021;103-B(1):65-70.

Assessment of a Satisfaction Measure for Use After Primary Total Joint Arthroplasty.

BACKGROUND: Patient satisfaction after total hip (THA) and total knee arthroplasty (TKA) is a core outcome selected by the Outcomes Measurement in Rheumatology. Up to 20% of THA/TKA patients are dissatisfied. Improving patient satisfaction is hindered by the lack of a validated measurement tool that can accurately measure change. METHODS: The psychometric properties of a proposed satisfaction instrument, consisting of 4 questions rated on a Likert scale, scored 1-100, were tested for validity, reliability, and sensitivity to change using data collected between 2007 and 2011 in an arthroplasty registry. RESULTS: We demonstrated construct validity by confirming our hypothesis; satisfaction correlated with similar constructs. Satisfaction correlated moderately with pain relief (TKA ρ = 0.61, THA ρ = 0.47) and function (TKA ρ = 0.65, THA ρ = 0.51) at 2 years; there was no correlation with baseline/preoperative pain/function values, as expected. Overall Cronbach's alpha >0.88 confirmed internal consistency. Test-retest reliability with weighted kappa ranged 0.60-0.75 for TKA and 0.36-0.56 for THA. Hip disability and Osteoarthritis Outcome Score/Knee injury and Osteoarthritis Outcome Scores quality of life improvement (>30 points) corresponds to a mean satisfaction score of 93.2 (standard deviation, 11.5) after THA and 90.4 (standard deviation, 13.8) after TKA, and increasing relief of pain and functional improvement increased the strength of their association with satisfaction. The satisfaction measure has no copyright and is available free of cost and represents minimal responder burden. CONCLUSION: Patient satisfaction with THA/TKA can be measured with a validated 4-item questionnaire. This satisfaction measure can be included in a total joint arthroplasty core measurement set for total joint arthroplasty trials.

One-Stage Periprosthetic Joint Infection Reimbursement-Is It Worth The Effort?

BACKGROUND: One-stage protocols for the management of periprosthetic infection take an extended period of time requiring two separate preps and sets of instruments to ensure optimal sterility. While intraoperative service time is one part of the reimbursement algorithm, reimbursement has lagged behind for single-stage treatment with respect to the time and resources necessary to perform these complex treatment regimens. If one-stage results are shown to be acceptable, but not reimbursed appropriately, surgeons will be discouraged from managing periprosthetic joint infection (PJI) in a one-stage fashion. METHODS: The reimbursement and operative time for 50 PJI procedures were compared with 250 primary total hips and 250 primary total knees by the same 4 surgeons. RESULTS: The average reimbursement for a one-stage knee procedure was $2,597.08, with an average intraoperative service time of 259 minutes ($601.60/h). The average reimbursement for a primary total knee was $2,435.00, with an average intraoperative service time of 100 minutes ($1,461/h). The average reimbursement for a one-stage hip procedure was $2,826.17, with an average intraoperative service time of 311 minutes ($545.24/h). The average reimbursement for a primary total hip was $2,754.71 with an average intraoperative service time of 104 minutes ($1,589.26/h). CONCLUSION: One-stage procedures for PJI are reimbursed at approximately 1/3 the hourly rate of a primary procedure, which may discourage surgeons from selecting this treatment alternative even if recent studies confirm efficacy. Payers should be encouraged to reimburse physicians commensurate with the intraoperative service time needed to perform a one-stage procedure as adoption will decrease morbidity and save the healthcare system financially.

What Are the Migration Patterns for U.S. Primary Total Joint Arthroplasty Patients?

BACKGROUND: Evaluation of total joint arthroplasty (TJA) patient-reported outcomes and survivorship requires that records of the index and potential revision arthroplasty procedure are reliably captured. Until the goal of the American Joint Replacement Registry (AJRR) of more-complete nationwide capture is reached, one must assume that patient migration from hospitals enrolled in the AJRR to nonAJRR hospitals occurs. Since such migration might result in loss to followup and erroneous conclusions on survivorship and other outcomes of interest, we sought to quantify the level of migration and identify factors that might be associated with migration in a specific AJRR population. QUESTIONS/PURPOSES: (1) What are the out-of-state and within-state migration patterns of U.S. Medicare TJA patients over time? (2) What patient demographic and institutional factors are associated with these patterns? METHODS: Hospital records of Medicare fee-for-service beneficiaries enrolled from January 1, 2004 to December 31, 2015, were queried to identify primary TJA procedures. Because of the nationwide nature of the Medicare program, low rates of loss to followup among Medicare beneficiaries, as well as long-established enrollment and claims processing procedures, this database is ideal for examining patient migration after TJA. We identified an initial cohort of 5.33 million TJA records from 2004 to 2016; after excluding patients younger than 65 years of age, those enrolled solely due to disability, those enrolled in a Medicare HMO, or residing outside the United States, the final analytical dataset consisted of 1.38 million THAs and 3.03 million TKAs. The rate of change in state or county of residence, based on Medicare annual enrollment data, was calculated as a function of patient demographic and institutional factors. A multivariate Cox model with competing risk adjustment was used to evaluate the association of patient demographic and institutional factors with risk of out-of-state or out-of-county (within-state) migration. RESULTS: One year after the primary arthroplasty, 0.61% (95% confidence interval [CI], 0.60-0.61; p < 0.001 for this and all comparisons in this Results section) of Medicare patients moved out of state and another 0.62% (95% CI, 0.60-0.63) moved to a different county within the same state. Five years after the primary arthroplasty, approximately 5.41% (95% CI, 5.39-5.44) of patients moved out of state and another 5.50% (95% CI, 5.46-5.54) Medicare patients moved to a different county within the same state. Among numerous factors of interest, women were more likely to migrate out of state compared with men (hazard ratios [HR], 1.06), whereas black patients were less likely (HR, 0.82). Patients in the Midwest were less likely to migrate compared with patients in the South (HR, 0.74). Patients aged 80 and older were more likely to migrate compared with 65- to 69-year-old patients (HR, 1.19). Patients with higher Charlson Comorbidity Index scores compared with 0 were more likely to migrate (index of 5+; HR, 1.19). CONCLUSIONS: Capturing detailed information on patients who migrate out of county or state, with associated changes in medical facility, requires a nationwide network of participating registry hospitals. At 5 years from primary arthroplasty, more than 10% of Medicare patients were found to migrate out of county or out of state, and the rate increases to 18% after 10 years. Since it must be assumed that younger patients might exhibit even higher migration levels, these findings may help inform public policy as a "best-case" estimate of loss to followup under the current AJRR capture area. Our study reinforces the need to continue aggressive hospital recruitment to the AJRR, while future research using an increasingly robust AJRR database may help establish the migration patterns of nonMedicare patients. LEVEL OF EVIDENCE: Level III, therapeutic study.

Are Ceramic Bearings Becoming Cost-Effective for All Patients Within a 90-Day Bundled Payment Period?

BACKGROUND: We analyzed whether the total hospital cost in a 90-day bundled payment period for ceramic-on-polyethylene (C-PE) and ceramic-on-ceramic (COC) total hip arthroplasty (THA) bearings was changing over time, and whether the cost differential between ceramic bearings and metal-on-polyethylene (M-PE) bearings was approaching the previously published tipping point for cost-effectiveness of US$325. METHODS: A total of 245,077 elderly Medicare patients (65+) who underwent primary THA between 2010 and 2015 were identified from the United States Medicare 100% national administrative hospital claims database. The total inpatient cost, calculated up to 90 days after index discharge, was computed using cost-to-charge ratios, and hospital payment was analyzed. The differential total inpatient cost of C-PE and COC bearings, compared to metal-on-polyethylene (M-PE), was evaluated using parametric and nonparametric models. RESULTS: After adjustment for patient and clinical factors, and the year of surgery, the mean hospital cost up to 90 days for primary THA with C-PE or COC was within ±1% of the cost for primary THA with M-PE bearings (P < .001). From the nonparametric analysis, the median total hospital cost was US$296-US$353 more for C-PE and COC than M-PE. Cost differentials were found to decrease significantly over time (P < .001). CONCLUSION: Patient and clinical factors had a far greater impact on the total cost of inpatient THA surgery than bearing selection, even when including readmission costs up to 90 days after discharge. Our findings indicate that the cost-effectiveness thresholds for ceramic bearings relative to M-PE are changing over time and increasingly achievable for the Medicare population.

Cognitive Training for Robotic Arm-Assisted Unicompartmental Knee Arthroplasty through a Surgical Simulation Mobile Application.

Advances in mobile device technology combined with the implementation of surgical simulation have led to the development of novel applications (apps) as a potential learning tool for surgical trainees. Touch Surgery (TS) (Kinosis Limited, London, United Kingdom) is a mobile-based app that combines cognitive task analysis with a virtual reality medium to familiarize the user with a surgical procedure through interactive rehearsal. The purpose of this study was to compare the educational efficacy of the TS app with a traditional paper-based learning program in performing a robotic arm-assisted unicompartmental knee arthroplasty. Twelve participants (four interns, four residents, four adult reconstructive fellows) were randomized to a paper-based technique guide or learning modules from the Mako Partial Knee (Stryker, Mahwah, NJ) TS app. Trainees were subjected to a baseline pretest. After preparing with the allocated training tool, participants completed an immediate posttest followed by a retention test administered 3 weeks later. The TS simulation group demonstrated greater improvement (22% score increase; p = 0.001) in posttest assessment compared with the control group (10% score increase; p = 0. 09). The TS simulation group demonstrated better information recall compared with the control group based on the score differential following the 3-week retention test. This randomized comparative study demonstrated that the TS app was better than traditional paper-based learning for both immediate posttest performance and long-term information recall of the Mako robotic arm-assisted unicompartmental knee arthroplasty. Surgical simulation apps may be an effective learning tool for surgical trainees.

Practice Management Strategies Among Current Members of the American Association of Hip and Knee Surgeons.

BACKGROUND: At the 2017 annual meeting of the American Association of Hip and Knee Surgeons (AAHKS), a survey was conducted to assess current practice management strategies by AAHKS members. METHODS: During the annual AAHKS meeting, a survey was conducted using an audience response system. The moderator queried AAHKS members with respect to a variety of practice management issues. The survey included both multiple choice and yes or no questions. The answers were collected in a central database and provided to the audience in real time. RESULTS: The survey responses provided valuable information with respect to the practice activity of AAHKS members. A total of 47% of AAHKS members are in private practice, and fee for service remains the major form of compensation for 39% of the membership. Participation in bundled-payment programs was 46%. A minority (22%) had performed a total joint arthroplasty in an outpatient surgery center. CONCLUSION: This survey of AAHKS members' practice patterns provided interesting data. Future surveys should determine potential changes in practice activity related to private practice, fee for service compensation, the use of outpatient surgery centers for total joint arthroplasty, and surgeon participation in bundled-payment programs.

Are Ceramic Bearings Becoming Cost-Effective for All Patients?

BACKGROUND: The purpose of this study is to analyze whether the cost for ceramic-on-polyethylene (C-PE) and ceramic-on-ceramic (COC) bearings used in primary total hip arthroplasty (THA) was changing over time, and if the cost differential between ceramic bearings and metal-on-polyethylene (M-PE) bearings was approaching the previously published tipping point for cost-effectiveness of $325. METHODS: A total of 245,077 elderly Medicare patients (65+) who underwent primary THA between 2010 and 2015 were identified from the United States Medicare 100% national administrative hospital claims database. The inpatient hospital cost, calculated using cost-to-charge ratios, and hospital payment were analyzed. The differential cost of C-PE and COC bearings, compared to M-PE, were evaluated using parametric and nonparametric models. RESULTS: After adjustment for patient and clinical factors, and the year of surgery, the mean hospital cost and payments for primary THA with a C-PE or COC was within ±1% of the cost for primary THA with M-PE bearings (P < .001). From the nonparametric analysis, the median hospital cost was $318-$360 more for C-PE and COC than M-PE. The differential in median Medicare payment for THA with ceramic bearings compared to M-PE was <$100. Cost differentials were found to decrease significantly over time (P < .001). CONCLUSION: Patient and clinical factors had a far greater impact on the cost of inpatient THA surgery than bearing selection. Because we found that costs and cost differentials for ceramic bearings were decreasing over time, and approaching the tipping point, it is likely that the cost-effectiveness thresholds relative to M-PE are likewise changing over time and should be revisited in light of this study.

Outcomes of Ceramic Bearings After Primary Total Hip Arthroplasty in the Medicare Population.

BACKGROUND: The purpose of this study was to analyze the outcomes of ceramic bearings used in primary total hip arthroplasty (THA) in the Medicare population. METHODS: A total of 315,784 elderly Medicare patients (65+) who underwent primary THA between 2005 and 2014 were identified from the United States Medicare 100% national administrative hospital claims database. Outcomes of interest included infection, dislocation, revision, or mortality at any time point after primary surgery. Propensity scores were developed to adjust for selection bias in the choice of bearing type at index primary surgery. RESULTS: For primary THA patients treated with ceramic-on-polyethylene (C-PE) bearings and ceramic-on-ceramic (COC) bearings, there was significantly reduced risk of infection relative to metal-on-polyethylene (M-PE) bearings (C-PE hazard ratio [HR]: 0.86, P = .001; COC HR: 0.74, P = .01). For the C-PE cohort, we also observed reduced risk of dislocation (HR: 0.81, P < .001) and mortality (HR: 0.92, P < .001). There was no significant difference in risk of revision for either the C-PE or COC bearing cohorts when compared with M-PE. For the COC cohort, there was no significant difference in dislocation or mortality risk. CONCLUSION: As in previous studies, we found that ceramic bearings have similar overall revision risk as M-PE bearings in primary THA at 8-9 years of follow-up. The results indicate that, after adjusting for selection bias and various confounding patient-, surgeon-, and hospital-related factors, Medicare primary THA patients treated with ceramic bearings exhibit lower risk of infection than those treated with M-PE bearings. In addition, C-PE bearings were associated with lower risk of dislocation and mortality.