Strikingly High Rates of Periprosthetic Joint Infection Following Revision Surgery for Periprosthetic Fractures Regardless of Surgery Timing.

BACKGROUND: Periprosthetic fractures following total hip arthroplasty (THA) often occur in the early postoperative period. Recent data has indicated that early revisions are associated with higher complication rates, particularly periprosthetic joint infection (PJI). The purpose of this study was to assess the effect of timing of periprosthetic fracture surgery on complication rates. We hypothesized that complication rates would be significantly higher in revision surgeries performed within 3 months of the index THA. METHODS: The Medicare Part A claims database was queried from 2010 to 2017 to identify patients who underwent surgery for a periprosthetic fracture following primary THA. Patients were divided based on time between index and revision surgeries: <1, 1 to 2, 2 to 3, 3 to 6, 6 to 9, 9 to 12, and >12 months. Complication rates were compared between groups using multivariate analyses to adjust for demographics, comorbidities, and types of revision surgery. RESULTS: Of 492,340 THAs identified, 4,368 (0.9%) had a subsequent periprosthetic fracture requiring surgery: 1,725 (39.4%) at <1 month, 693 (15.9%) at 1 to 2 months, 202 (4.6%) at 2 to 3 months, 250 (5.7%) at 3 to 6 months, 134 (3.1%) at 6 to 9 months, 85 (19.4%) at 9 to12 months, and 1,279 (29.3%) at >12 months. The risk of PJI was 11.0% in the <1 month group, 11.1% at 1 to 2 months, 7.9% at 2 to 3 months, 6.8% at 3 to 6 months, 8.2% at 6 to 9 months, 9.4% at 9 to 12 months, and 8.5% at >12 months (P = .12). Adjusting for confounding factors, risk of PJI following periprosthetic fracture surgery was similar regardless of timing (P > .05). Rates of subsequent dislocation and aseptic loosening were also similar regardless of timing. CONCLUSIONS: The risk of PJI following repeat surgery for a periprosthetic fracture was strikingly high regardless of timing (6.8 to 11.1%), underscoring the high-risk of complications.

Complications and costs of patellofemoral arthroplasty versus total knee arthroplasty.

BACKGROUND: Patellofemoral arthroplasty (PFA) is an alternative to total knee arthroplasty (TKA) for the treatment of patellofemoral arthritis. Although PFA may preserve native kinematics and accelerate recovery, it has been associated with higher revision rates. The purpose of this study is to compare complication rates and costs between PFA and TKA. METHODS: Using the PearlDiver database, 6,179 patients with isolated patellofemoral arthritis treated with PFA or TKA from 2010-2015 were retrospectively reviewed with 5-year follow up. PFA and TKA patients were matched by age, sex, and Elixhauser Comorbidity Index via a 1:1 stepwise algorithm. Five-year costs and complications were compared between matched cohorts. The lifetime costs of PFA and TKA were evaluated with Markov decision modeling. RESULTS: Compared to TKA, PFA was associated with fewer Emergency Department (ED) visits (6.1% vs 3.9%, p = 0.004) but a higher 5-year revision rate (9.9% vs 4.2%, p < 0.001). After multivariate regression, PFA was independently more likely to require revision (odds ratio 2.60, 95% confidence interval 1.32-4.71, p = 0.003). PFA was associated with lower total healthcare costs at every time point between 3 months ($18,014 vs $26,473, p < 0.001) and 5 years ($20,837 vs $27,942, p < 0.001). On average, the lifetime cost of PFA per patient was $5,235 less than for TKA ($26,343 vs $31,578). CONCLUSIONS: PFA is a less expensive alternative to TKA with a similar risk of medical complications but is associated with a significantly higher 5-year revision rate. Future studies should examine the reasons for PFA failure and methods to mitigate this risk.

Over Half of All Medicare Total Knee Arthroplasty Patients Are Now Classified as an Outpatient-Three-Year Impact of the Removal From the Inpatient-Only List.

BACKGROUND: In 2018, Centers for Medicare & Medicaid Services removed total knee arthroplasty (TKA) from its inpatient-only list, triggering many unintended consequences. The purpose of this study was to determine how the impact of TKA removal affected the number of outpatient TKA patients, which patients were being labeled outpatient, and how outpatient classification affected discharge location and readmission rates. METHODS: Using a large administrative claims database, we reviewed a consecutive series of 216,365 primary TKA Medicare patients from 2015 to 2020. Patients who had an inpatient status (n = 63,356) were compared to patients who had an outpatient status (n = 38,510) from 2018 to 2020 based on demographics, comorbidities, discharge dispositions, and readmissions. RESULTS: In 2015, only 1.8% of TKA patients were designated as outpatients, but by 2020, 57.2% of Medicare TKA patients were classified as outpatients. A majority of patients (72%) who had an outpatient designation remained in the hospital for >24 hours (average length of stay was 2.7 days). Patients who had an outpatient status were discharged to skilled nursing facilities more frequently than patients who had an inpatient status (3.1 versus 2.0%, P < .001) with increased emergency visits (5.1 versus 3.9%, P < .001) and 90-day readmissions (2.2 versus 0.9%, P < .001). CONCLUSION: Over half of all Medicare TKA patients are being classified as outpatients 3 years following the policy to remove TKA from the inpatient-only list. Patients designated as outpatients had higher readmissions than those designated as inpatients. This policy should be re-evaluated in the context of failure to demonstrate safer discharge of Medicare patients who undergo TKA.

The Cost-Effectiveness of Tibial Metaphyseal Cones in Revision Total Knee Arthroplasty.

BACKGROUND: The purpose of this study is to evaluate the cost-effectiveness of tibial cones in revision total knee arthroplasty. METHODS: A Markov model was used for cost-effectiveness analysis. The average cone price was obtained from Orthopedic Network News. The average cone aseptic loosening rate was determined by literature review. Hospitalization costs and baseline re-revision rates were calculated using the PearlDiver Database. RESULTS: The maximum cost-effective cone price varied from $3514 at age 40 to $648 at age 90, compared to the current average selling price of $4201. Cones became cost-effective with baseline aseptic loosening rates of 0.89% annually at age 40 to 4.38% annually at age 90, compared to the current average baseline loosening rate of 0.76% annually. CONCLUSION: For the average patient, tibial cones are not cost-effective, but may become so at lower prices, in younger patients, or in patients at substantially increased risk of aseptic loosening.

National Trends in Post-Acute Care Costs Following Total Hip Arthroplasty from 2010 through 2018.

BACKGROUND: Post-acute care remains a target for episode-of-care cost reduction following total hip arthroplasty (THA). The introduction of bundled payment models in the United States in 2013 aligned incentives among providers to reduce post-acute care resource utilization. Institution-level studies have shown increased rates of home discharge with substantial cost savings after adoption of bundled payment models; however, national data have yet to be reported. The purpose of this study was to evaluate national trends in post-acute care utilization and costs following primary THA over the last decade. METHODS: We reviewed the cases of 189,847 patients undergoing primary THA during 2010 through 2018 from the PearlDiver database. Annual trends in patient demographics, discharge disposition, and post-acute care resource utilization were evaluated. Post-acute care reimbursements were standardized to 2020 dollars and included outpatient visits, prescriptions, physical therapy, home health, inpatient rehabilitation, skilled nursing facilities, and any rehospitalizations or emergency department (ED) visits within 90 days of surgery. RESULTS: From 2010 to 2018, the mean episode-of-care costs ($31,562 versus $24,188; p < 0.001) and overall post-acute care costs ($5,903 versus $3,485; p < 0.001) both declined. Post-acute care savings were primarily driven by reduced costs of skilled nursing facilities ($1,533 versus $627; p < 0.001), home health ($1,041 versus $763; p = 0.002), inpatient rehabilitation ($949 versus $552; p < 0.001), ED visits ($508 versus $102; p < 0.001), and rehospitalizations ($367 versus $179; p < 0.001). Post-acute care costs declined by $578 (p = 0.025) during 2010 to 2012, $768 (p = 0.038) during 2013 to 2015, and $884 (p = 0.020) during 2016 to 2018. CONCLUSIONS: Over the last decade, the rate of home discharge after THA increased while rehospitalization and ED visit rates declined, resulting in a substantial decrease in total and post-acute care costs. Post-acute care costs declined most rapidly after the introduction of the new Medicare bundled payment programs in 2013 and 2016.

Home Health Care in Medicare-Aged Patients is Associated With Increased Early Emergency Visits, Readmissions, and Costs Following Total Knee Arthroplasty.

BACKGROUND: Home health services are utilized in order to provide at-home care following total knee arthroplasty (TKA). The purpose of this study is to determine whether patients receiving home health services post-operatively had lower rates of complications, emergency room visits, and readmissions as well as to determine if home health provided value by reducing total episode-of-care costs. METHODS: The PearlDiver database was retrospectively reviewed to identify all primary TKA patients over 65 years old from 2010 to 2018. Patients who received home health services were matched using a propensity score algorithm to a set of similar patients who were discharged home under self-care. We compared complication rates, emergency room visits, readmissions, and 90-day episode-of-care claims costs between the groups. Multivariate regression analysis was performed to determine the independent effect of home health services on emergency department (ED) visits and hospital readmissions. RESULTS: Of the 185,444 TKA patients discharged home, 15,849 (8.5%) received home health services. Patients who received home health services had higher rates of ED visits at 2 weeks (3.3% vs 2.8%, P = .014) and 3 months (7.1% vs 6.5%, P = .038) as well as increased readmissions at 2 weeks (0.9% vs 0.7%, P = .028); complication rates were similar between groups (11.4% vs 10.9%, P = .159). Episode-of-care costs for home health patients were higher than those discharged under self-care ($24,266 vs $22,539, P < .001). CONCLUSION: Home health services do not appear to provide value as they are associated with significantly increased costs and do not lower the rates of complications, ED visits, or readmissions following TKA.

Costs of unicompartmental compared with total knee arthroplasty : a matched cohort study over ten years.

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.

National Trends in Post-Acute Care Costs Following Total Knee Arthroplasty From 2007 to 2016.

BACKGROUND: Post-acute care continues to represent a target for cost savings with increasing popularity of value-based payment models in total knee arthroplasty (TKA). Rapid recovery and accelerated rehabilitation protocols have been successful in reducing costs at the institutional level, but national trends are less clear. This study aimed to determine if advancements in perioperative care led to a reduction in post-acute care costs and resource utilization following TKA. METHODS: We reviewed a consecutive series of 79,843 primary TKA patients from the Humana claims dataset from 2007 to 2016. Post-acute care costs included any claims within 90 days of surgery for subacute or inpatient rehabilitation, home health, outpatient or emergency visits, prescription medications, physical therapy, and readmissions. Demographics, episode-of-care and post-acute care costs, readmissions, and discharge disposition were compared. Controlling for demographics and comorbidities, multivariate regression analyses were performed to compare trends in discharge disposition and post-acute care costs. RESULTS: From 2007 to 2016, the average episode-of-care costs ($46,754 vs $31,856) and post-acute care costs per patient decreased ($20,224 vs $13,498). Rates of discharge to skilled nursing facilities (25.0% vs 22.5%) and inpatient rehabilitation also declined (12.4% vs 2.1%). Readmissions also decreased (8.1% vs 7.1%) saving an average of $324 per patient. When compared to 2007-2012, total costs declined most rapidly after 2013 primarily due to a $3516 (21%) decrease in post-acute spending. CONCLUSION: There has been a substantial decline in post-acute care costs and resource utilization following TKA, with the largest decrease occurring following the introduction of Medicare bundled payment models in 2013.

Revision Surgery for Instability After Total Hip Arthroplasty: Does Timing Matter?

BACKGROUND: Instability is a common reason for revision surgery after total hip arthroplasty (THA). Recent studies suggest that revisions performed in the early postoperative period are associated with higher complication rates. The purpose of this study is to assess the effect of timing of revision for instability on subsequent complication rates. METHODS: The Medicare Part A claims database was queried from 2010 to 2017 to identify revision THAs for instability. Patients were divided based on time between index and revision surgeries: <1, 1-2, 2-3, 3-6, 6-9, 9-12, and >12 months. Complication rates were compared between groups using multivariate analyses to adjust for demographics and comorbidities. RESULTS: Of 445,499 THAs identified, 9298 (2.1%) underwent revision for instability. Revision THA within 3 months had the highest rate of periprosthetic joint infection (PJI): 14.7% at <1 month, 12.7% at 1-2 months, and 10.6% at 2-3 months vs 6.9% at >12 months (P < .001). Adjusting for confounding factors, PJI risk remained elevated at earlier periods: <1 month (adjusted odds ratio [aOR]: 1.84, 95% confidence interval [CI]: 1.51-2.23, P < .001), 1-2 months (aOR: 1.45, 95% CI: 1.16-1.82, P = .001), 2-3 months (aOR: 1.35, 95% CI: 1.02-1.78, P = .036). However, revisions performed within 9 months of index surgery had lower rates of subsequent instability than revisions performed >12 months (aOR: 0.67-0.85, P < .050), which may be due to lower rates of acetabular revision and higher rates of head-liner exchange in this later group. CONCLUSION: When dislocation occurs in the early postoperative period, delaying revision surgery beyond 3 months from the index procedure may be warranted to reduce risk of PJI.

Patient Attitudes Toward Resident and Fellow Participation in Orthopedic Surgery.

BACKGROUND: Residents' and fellows' participation in orthopedic surgery is a potential source of anxiety and concern for patients. The purpose of this study was to determine patients' attitudes toward trainee involvement in orthopedic surgery, surgeons as educators, and disclosure of trainee involvement. METHODS: Three hundred two consecutive patients with preoperative and postoperative appointments at three arthroplasty practices in academic medical centers were surveyed with an anonymous, self-administered questionnaire. The questionnaire was developed in consultation with an expert in survey design. RESULTS: Two hundred thirty-four patients completed the questionnaire (response rate 77.5%). Respondents were 60.5% female, 79.6% white, 66.5% privately insured, and 82.8% had at least some college education. About 65.9% of the respondents felt that surgeons who teach are better surgeons. Nearly all felt residents and fellows should perform surgeries as part of their education (94.1% and 95.3%, respectively). However, 39.7% of the respondents were not satisfactory with a second-year resident assisting in their own surgery. Patients dissatisfied with their most recent orthopedic surgery were more likely to respond that they did not want residents helping with their surgery. Respondents agreed that resident or fellow involvement in surgery should be disclosed (92.2% and 90.1%, respectively). CONCLUSIONS: Insured and educated patients in the United States overwhelmingly desire disclosure of trainee involvement in their surgery. To address the need for orthopedic training in the context of a patient population that is not fully comfortable with trainee involvement in their own surgery, an open discussion between patients and surgeons regarding trainees' roles may be the best course of action.

The Unintended Impact of the Removal of Total Knee Arthroplasty From the Center for Medicare and Medicaid Services Inpatient-Only List.

BACKGROUND: Total knee arthroplasty (TKA) was removed from the Centers for Medicare and Medicaid Services (CMS) Inpatient-Only (IPO) list starting January 1, 2018. Many hospitals responded by instructing surgeons to schedule all TKAs as outpatient procedures, and some local Medicare Advantage contractors began to expect outpatient status for all or most TKA cases. This activity and ensuing confusion has caused considerable unintended disruption for surgeons, hospitals, and patients. The purpose of this study was to gauge the impact on providers and patients. METHODS: Active members of the American Association of Hip and Knee Surgeons were sent a 9-question survey asking if the surgeon's hospital was treating all patients undergoing TKA as outpatients and if Medicare Advantage administrators and commercial payers were treating all or most the same. Questions also inquired about the impact on surgeon practices and their patients. RESULTS: Seven hundred thirty members (26%) responded; of which, 59.5% reported that their hospitals have instructed them that all Medicare TKAs should be scheduled as outpatient procedures; 40.5% have been asked to use proscribed documentation to justify that change; 30.4% reported that their patients have incurred added personal cost secondary to their surgical procedure being billed as an outpatient procedure; and 76.1% report that this issue has become an administrative burden. CONCLUSION: The CMS clearly stated its expectation in the 2018 Outpatient Prospective Payment System Final Rule that the great majority of Medicare fee-for-service TKA patients would continue to be treated as inpatients. Nonetheless, many hospitals have decided to schedule all TKA cases as outpatients due to the 2-midnight rule despite a moratorium on recovery audits. It is the position of the American Association of Hip and Knee Surgeons that the CMS needs to provide more specific expectations concerning the needed language justifying admission or exempt TKA from the 2-midnight rule to mitigate the unintended confusion demonstrated by hospitals and some payers that has resulted from the removal of TKA from the Inpatient-Only list.

Risk Adjustment Is Necessary in Medicare Bundled Payment Models for Total Hip and Knee Arthroplasty.

BACKGROUND: Concerns exist that high-risk patients in alternative payment models may face difficulties with access to care without proper risk adjustment. The purpose of this study is to identify the effect of medical and orthopedic specific risk factors on the cost of a 90-day episode of care following total hip (THA) and knee arthroplasty (TKA). METHODS: We queried the Medicare 5% Limited Data Set for all patients undergoing primary THA and TKA from 2010 to 2014. To evaluate the cost of an episode of care, we calculated all claims for 90 days following surgery. Multivariate analysis was performed to quantify the added episode-of-care costs for demographic variables, geography, medical comorbidities, and orthopedic specific risk factors. RESULTS: Of the 58,809 TKA patients, the median 90-day Medicare costs was $23,800 (interquartile range, $18,900-$32,300), while the median of the 27,293 THA patients was $24,000 (interquartile range, $18,500-$33,900). Independent risk factors (all P < .05) resulting in at least a 10% increase in episode-of-care costs following TKA included malnutrition, age over 85, male gender, pulmonary disorder, failed internal fixation, Northeast region, lower socioeconomic status, neurologic disorder, and rheumatoid arthritis. Independent risk factors (all P < .05) resulting in at least a 10% increase in episode-of-care costs following THA included malnutrition, male gender, age over 85, failed internal fixation, hip dysplasia, Northeast region, neurologic disorder, lower socioeconomic status, conversion THA, avascular necrosis, and depression. CONCLUSION: Certain comorbidities and orthopedic risk factors increase 90-day episode-of-care costs in the Medicare population. The current lack of proper risk stratification could be a powerful driver of decreased access to care for our most medically challenged members of society.

Can Total Knee Arthroplasty Be Performed Safely as an Outpatient in the Medicare Population?

BACKGROUND: The Centers for Medicare and Medicaid Services has solicited public comments for the 2017 Proposed Rule to consider removing total knee arthroplasty (TKA) from the Inpatient Only List. The purpose of this study is to compare the complication rates between outpatient (same-day discharge), short-stay (discharge within 1 day), and inpatient TKA and to identify the ideal candidates for a short-stay or outpatient procedure. METHODS: We queried the American College of Surgeons-National Surgical Quality Improvement Program database for patients over age 65 years who underwent TKA from 2014 to 2015. Demographics, comorbidities, 30-day complications, and readmission rates were compared between patients after outpatient, short-stay, and inpatient procedures. A multivariate regression analysis was then performed to identify at-risk patients who should not be candidates for outpatient or short-stay TKA. RESULTS: Of the 49,136 Medicare-aged TKA patients, 365 (0.7%) were outpatient, 3033 (6%) were short-stay and 45,738 (93%) were inpatient. Short-stay patients had a lower complication rate than both the outpatient and inpatient groups (2% vs. 8% vs. 8%, P < .001). Independent risk factors (all P < .05) for experiencing a complication or requiring an inpatient stay include female gender (odds ratio [OR] 1.655), general anesthesia (OR 1.282), diabetes mellitus (OR 1.171), chronic obstructive pulmonary disease (OR 1.579, P < .001), hypertension (OR 1.144), kidney disease (OR 1.425), American Society of Anesthesiologists Score 4 (OR 1.748), body mass index >35 kg/m2 (OR 1.265), and age >75 years (OR 1.429). CONCLUSION: TKA can be performed safely as an outpatient in a subset of healthy Medicare patients with a complication rate similar to an inpatient stay. A 23-hour stay, however, may be the "sweet spot" that minimizes complications in this population.

Improving Value in Total Hip and Knee Arthroplasty: The Role of High Volume Hospitals.

BACKGROUND: Recent healthcare reform efforts have focused on improving the quality of total joint replacement care while reducing overall costs. The purpose of this study is to determine if higher volume centers have lower costs and better outcomes than lower volume hospitals. METHODS: We queried the Centers for Medicare and Medicaid Services (CMS) Inpatient Charge Data and identified 2702 hospitals that performed a total of 458,259 primary arthroplasty procedures in 2014. Centers were defined as low (performing <100 total joint arthroplasty [TJA] per year) or high volume and mean total hospital-specific charges and inpatient payments were obtained. Patient satisfaction scores as well 30-day risk-adjusted complication and readmission scores were obtained from the multiyear CMS Hospital Compare database. RESULTS: Of all the hospitals, 1263 (47%) hospitals were classified as low volume and performed 60,895 (12%) TJA cases. Higher volume hospitals had lower mean total hospital-specific charges ($56,323 vs $60,950, P < .001) and mean Medicare inpatient payments ($12,131 vs $13,289, P < .001). Higher volume facilities had a lower complication score (2.96 vs 3.16, P = .015), and a better CMS hospital star rating (3.14 vs 2.89, P < .001). When controlling for hospital geographic and demographic factors, lower volume hospitals are more likely to be in the upper quartile of inpatient Medicare costs (odds ratio 2.127, 95% confidence interval 1.726-2.621, P < .001). CONCLUSION: Hospitals that perform <100 TJA cases per year may benefit from adopting the practices of higher volume centers in order to improve quality and reduce costs.

Risk Adjustment Is Necessary in Value-based Outcomes Models for Infected TKA.

BACKGROUND: The Medicare Access and CHIP Reauthorization Act of 2015 provides the framework to link reimbursement for providers based on outcome metrics. Concerns exist that the lack of risk adjustment for patients undergoing revision TKA for an infection may cause problems with access to care. QUESTIONS/PURPOSES: (1) After controlling for confounding variables, do patients undergoing revision TKA for infection have higher 30-day readmission, reoperation, and mortality rates than those undergoing revision TKA for aseptic causes? (2) Compared with patients undergoing revision TKA who are believed not to have infections, are patients undergoing revision for infected TKAs at increased risk for complications? METHODS: We queried the American College of Surgeons National Surgical Quality Improvement Program database for patients undergoing revision TKA from 2012 to 2015 identified by Current Procedural Terminology (CPT) codes 27486, 27487, and 27488. Of the 10,848 patients identified, four were excluded with a diagnosis of malignancy (International Classification of Diseases, 9th Revision code 170.7, 170.9, 171.8, or 198.5). This validated, national database records short-term outcome data for inpatient procedures and does not rely on administrative coding data. Demographic variables, comorbidities, and outcomes were compared between patients believed to have infected TKAs and those undergoing revision for aseptic causes. A multivariate logistic regression analysis was performed to identify independent factors associated with complications, readmissions, reoperations, and mortality. RESULTS: After controlling for demographic factors and medical comorbidities, TKA revision for infection was independently associated with complications (odds ratio [OR], 3.736; 95% confidence interval [CI], 3.198-4.365; p < 0.001), 30-day readmission (OR, 1.455; 95% CI, 1.207-1.755; p < 0.001), 30-day reoperation (OR, 1.614; 95% CI, 1.278-2.037; p < 0.001), and 30-day mortality (OR, 3.337; 95% CI, 1.213-9.180; p = 0.020). Patients with infected TKA had higher rates of postoperative infection (OR, 3.818; 95% CI, 3.082-4.728; p < 0.001), renal failure (OR, 36.709; 95% CI, 8.255-163.231; p < 0.001), sepsis (OR, 7.582; 95% CI, 5.529-10.397; p < 0.001), and septic shock (OR, 3.031; 95% CI, 1.376-6.675; p = 0.006). CONCLUSIONS: Policymakers should be aware of the higher rate of mortality, readmissions, reoperations, and complications in patients with infected TKA. Without appropriate risk adjustment or excluding these patients all together from alternative payment and quality reporting models, fewer providers will be incentivized to care for patients with infected TKA. LEVEL OF EVIDENCE: Level III, therapeutic study.

Should Medicare Remove Total Knee Arthroplasty From Its Inpatient Only List? A Total Knee Arthroplasty Is Not a Partial Knee Arthroplasty.

BACKGROUND: The Centers for Medicare and Medicaid Services have solicited comments to consider removing total knee arthroplasty (TKA) from the Inpatient Only list, as it has done for unicompartmental knee arthroplasty (UKA). The purpose of this study is to determine whether Medicare-aged patients undergoing TKA had comparable outcomes to those undergoing UKA. METHODS: We queried the American College of Surgeons-National Surgical Quality Improvement Program database for all patients aged 65 years or older who underwent elective TKA or UKA from 2014 and 2015. Demographic variables, comorbidities, length of stay (LOS), 30-day complication, and readmission rates were compared between UKA and TKA patients. A multivariate regression analysis was then performed to identify independent risk factors for complications and hospital LOS greater than 1 day. RESULTS: Of the 50,487 patients in the study, there were 49,136 (97%) TKA patients and 1351 UKA patients (3%). Medicare-aged TKA patients had a longer mean LOS (2.97 vs 1.57 days, P < .001), had a higher complication rate (9% vs 3%, P < .001), and were more likely to be discharged to a rehabilitation facility (31% vs 9%, P < .001) than Medicare-aged UKA patients. When controlling for other variables, TKA patients were more likely to experience a complication (odds ratio, 2.562; P < .001) and require LOS >1 day (odds ratio, 14.679; P < .001) than UKA patients. CONCLUSION: TKA procedure in the Medicare population is an independent risk factor for increased complications and LOS compared to UKA. Policymakers should use caution extrapolating UKA data to TKA patients and recognize the inherent disparities between the 2 procedures.

Reconsidering the Affordable Care Act's Restrictions on Physician-Owned Hospitals: Analysis of CMS Data on Total Hip and Knee Arthroplasty.

BACKGROUND: Concerns about financial incentives and increased costs prompted legislation limiting the expansion of physician-owned hospitals in 2010. Supporters of physician-owned hospitals argue that they improve the value of care by improving quality and reducing costs. The purpose of the present study was to determine whether physician-owned and non-physician-owned hospitals differ in terms of costs, outcomes, and patient satisfaction in the setting of total hip arthroplasty (THA) and total knee arthroplasty (TKA). METHODS: With use of the U.S. Centers for Medicare & Medicaid Services (CMS) Inpatient Charge Data, we identified 45 physician-owned and 2,657 non-physician-owned hospitals that performed ≥11 primary TKA and THA procedures in 2014. Cost data, patient-satisfaction scores, and risk-adjusted complication and 30-day readmission scores for knee and hip arthroplasty patients were obtained from the multiyear CMS Hospital Compare database. RESULTS: Physician-owned hospitals received lower mean Medicare payments than did non-physician-owned hospitals for THA and TKA procedures ($11,106 compared with $12,699; p = 0.002). While the 30-day readmission score did not differ significantly between the 2 types of hospitals (4.48 compared with 4.62 for physician-owned and non-physician-owned, respectively; p = 0.104), physician-owned hospitals had a lower risk-adjusted complication score (2.83 compared with 3.04; p = 0.015). Physician-owned hospitals outperformed non-physician-owned hospitals in all patient-satisfaction categories, including mean linear scores for recommending the hospital (93.9 compared with 87.9; p < 0.001) and overall hospital rating (93.4 compared with 88.4; p < 0.001). When controlling for hospital demographic variables, status as a non-physician-owned hospital was an independent risk factor for being in the upper quartile of all inpatient payments for Medicare Severity-Diagnosis Related Group (MS-DRG) 470 (odds ratio, 3.317; 95% confidence interval, 1.174 to 9.371; p = 0.024), which may be because of a difference in CMS payment methodology. CONCLUSIONS: Our findings suggest that physician-owned hospitals are associated with lower mean Medicare costs, fewer complications, and higher patient satisfaction following THA and TKA than non-physician-owned hospitals. Policymakers should consider these data when debating the current moratorium on physician-owned hospital expansion. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

A cost comparison of unicompartmental and total knee arthroplasty.

BACKGROUND: Unicompartmental knee arthroplasty (UKA) is an alternative to total knee arthroplasty (TKA) in appropriately selected patients. There is a paucity of data comparing hospital resource utilization and costs for UKA versus TKA. METHODS: We retrospectively reviewed 128 patients who underwent UKA or TKA for osteoarthritis by a single surgeon in the 2011 Fiscal Year. Sixty-four patients in each group were matched based on sex, age, race, body mass index, Charlson Comorbidity Index, and insurance type. Clinical data were obtained from medical records while costs were obtained from hospital billing. Bivariate analyses were used to compare outcomes. RESULTS: Both anesthesia and operative time (minutes) were significantly shorter for patients undergoing UKA (125.7 vs. 156.4; p<0.001, and 81.4 vs. 112.2; p<0.001). UKA patients required fewer transfusions (0% vs. 11.0%; p=0.007) and had a shorter hospital stay (2.2 vs. 3.8days; p<0.001). 96% of UKAs were discharged home compared with 75% of TKAs (p<0.001). Hospital direct costs were lower for UKA ($7893 vs. $11,156; p<0.001) as were total costs (hospital direct costs plus overhead; $11,397 vs. $16,243; p<0.001). Supply costs and implant costs were similarly lower for UKA ($701 vs. $781; p<0.001, and $3448 vs. $5006; p<0.001). CONCLUSION: Our data suggest that UKA provides a cost-effective alternative to TKA in appropriately selected patients. As the number of patients with end-stage arthritis of the knee requiring surgical care continues to rise, the costs of caring for these patients must be considered. LEVEL OF EVIDENCE: Level III, case control study.

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

BACKGROUND: A survey was conducted at the 2015 annual meeting of the American Association of Hip and Knee Surgeons (AAHKS) to determine current practice management patterns among AAHKS members. METHODS: A survey was conducted by the session moderator during the annual AAHKS meeting using an audience response system. A series of practice management issues were reviewed with AAHKS members. The survey contained multiple choice and yes and no questions. The audience responses were collected in a central database and then immediately displayed for the audience to review. RESULTS: The survey responses provided interesting data on a variety of topics including: surgeon demographics, surgical activity, practice status, use of physician extenders, sources of ancillary income, the use of electronic medical records and surgeon satisfaction. Interestingly, 51% of AAHKS members remain in private practice and fee for service remains the most common form of compensation (48%). The vast majority of AAHKS members do not perform hip arthroscopy (86%) or hip preservation procedures (87%). CONCLUSION: Valuable information regarding practice patterns of AAHKS members was obtained from this survey. Future surveys will need to focus on 3 areas of activity: surgeon involvement in bundled payment programs frequency of submission of patient data to a joint registry and the frequency of outpatient total joint arthroplasty.