Accuracy of Intraoperative Mechanical Axis Alignment to Long-Leg Radiographs following Robotic-Arm-Assisted Unicompartmental Knee Arthroplasty.

Improper alignment and implant positioning following unicompartmental knee arthroplasty (UKA) has been shown to lead to postoperative pain and increase the incidence of revision procedures. The use of robotic-arm assistance for UKA (RAUKA) has become an area of interest to help overcome these challenges. The accuracy of intraoperative alignment compared with standing long-leg X-rays postoperatively following medial RAUKA has been in question. Therefore, the purpose of this study was to (1) determine final mean intraoperative coronal alignment in extension utilizing an image based intraoperative navigation system, and (2) compare final intraoperative alignment to 6-week weight-bearing (WB) long-leg X-rays. Patients who underwent RAUKA for medial compartmental osteoarthritis were identified from January 1, 2018, to August 31, 2019, through our institution's joint registry. The query yielded 136 (72 right and 64 left) patients with a mean age of 72.02 years and mean body mass index (BMI) of 28.65 kg/m2 who underwent RAUKA. Final intraoperative alignment was compared with WB long leg X-rays 6 weeks postoperatively by measuring the mechanical alignment. Statistical analysis was primarily descriptive. Pearson's correlation coefficient was used to determine the relationship between intraoperative alignment to 6-week alignment. A p-value of <0.05 was considered statistically significant. Mean intraoperative coronal alignment after resections and trialing was 4.39 varus ± 2.40 degrees for the right knee, and 4.81 varus ± 2.29 degrees for the left knee. WB long-leg X-rays 6 weeks postoperatively demonstrated mechanical axis alignment for the right and left knees to be 3.01 varus ± 2.10 and 3.7 varus ± 2.38 degrees, respectively. This resulted in a change in alignment of 1.36 ± 1.76 and 1.12 ± 1.84 degrees for the right and left knees, respectively (p < 0.05). Pearson's correlation coefficient demonstrated a correlation of 0.69 between intraoperative to long-leg-X-ray alignment. RAUKA demonstrates excellent consistency when comparing postoperative WB long-leg X-rays to final intraoperative image-based non-WB alignment.

The Effects of Patient Occupation, Hobbies, and Body Mass Index on Kneeling after Total Knee Arthroplasty.

A common patient concern after total knee arthroplasty (TKA) is the ability to kneel. Kneeling may have a substantial impact on the patients' ability to perform many activities of daily living, occupations, and hobbies. The purpose of this study was to quantify the percentage of patients able to kneel after TKA after 2 years and to evaluate preoperative patient characteristics that influence the patient's perceived ability to kneel after TKA such as obesity, occupation, and hobbies. We retrospectively assessed a cohort of 404 patients who underwent primary TKA with patellar resurfacing. We assessed the impact of patient hobbies, occupation, employment status, and body mass index (BMI) on the kneeling capacity and patient-reported satisfaction. Univariate analysis was performed using Fisher's exact test, and multivariate analysis was performed using logistic regression with multiple imputations. A total of 404 patients were included. Sixty percent of patients were unable to kneel after TKA. Males (p < 0.001) and patients with occupations or hobbies requiring kneeling (p < 0.05) were more likely to kneel after surgery. We identified an inverse relationship between BMI and the ability to kneel. No correlation was found between duration and frequency of kneeling relative to patient-reported ease or difficulty with kneeling. Patient-reported factors that prevented patients from kneeling were pain, physical inability, and fear of damaging the prosthesis. Patient education may be helpful in improving patient expectations about kneeling after surgery. A small but significant difference in subjective patient satisfaction was observed when comparing patients able to kneel with those unable to kneel.

Implant-Related Complications Among Patients With Opioid Use Disorder Following Primary Total Hip Arthroplasty: A Matched-Control Analysis of 42,097 Medicare Patients.

BACKGROUND: Opioid use disorders (OUD) are a major cause of morbidity and mortality. The authors of this study hypothesize that patients who have an OUD will have greater relative risk of implant-related complications, periprosthetic joint infections (PJIs), readmission rates, and will incur greater costs compared to non-opioid use disorder (NUD) patients following primary total hip arthroplasty (THA). METHODS: OUD patients who underwent a THA between 2005 and 2014 were identified and matched to controls in a 1:5 ratio according to age, sex, a comorbidity index, and various medical comorbidities yielding 42,097 patients equally distributed in both cohorts. Pearson's chi-square analyses were used to compare patient demographics. Relative risk (RR) was used to analyze and compare risk of 2-year implant-related complications, 90-day PJIs, and 90-day readmission rates. Welch's t-tests were used to compare day of surgery and 90-day episode-of-care costs between the cohorts. A P value less than .006 was considered statistically significant. RESULTS: OUD patients had higher incidences and risks of implant-related complications (11.99% vs 6.68%; RR, 1.74; P < .001), developing PJIs within 90 days (2.38% vs 1.81%; RR, 1.32; P = .001), and 90-day readmissions (21.49% vs 17.35%; RR, 1.23; P < .001). Additionally, the study demonstrated OUD patients incurred greater day of surgery ($14,384.30 vs $13,150.12, P < .0001) and 90-day costs ($21,183.82 vs $18,709.02, P < .0001) compared to controls. CONCLUSION: After controlling for age, sex, a comorbidity index, and various medical complications, OUD patients are at greater risk to experience implant-related complications, PJIs, readmissions, and have greater costs following primary THA compared to non-OUD patients. This study should help orthopedic surgeons counsel their patients of potential complications which may arise following their primary THA.

Operative Reports in Orthopaedic Surgery: The Need for Assessment and Education.

BACKGROUND: The ability to complete an operative report is a vital skill for an orthopaedic surgeon. We hypothesized that most programs do not have formal operative report teaching, that resident operative reports at our institution are incomplete, and that a formal teaching program would improve operative reports. METHODS: A survey of residencies in the United States was conducted assessing the state of operative report education. In addition, resident operative reports were collected at our institution both pre and post a formal educational session. Scores were given for each report out of a possible 35 points. RESULTS: Total 54 institutions responded to the survey, of which 83% indicated that they had no formal resident operative report teaching. Within our institution, 100 resident operative dictations were assessed prior to instituting a formal education session, with a mean score of 24.5. The most commonly missed items in the report were preoperative antibiotics, deep venous thrombosis prophylaxis, and tourniquet time. The mean score of 100 resident operative dictations following the educational session improved to 31.8. CONCLUSION: Most residency programs do not conduct formal resident operative report teaching. Formal instruction on how to complete a comprehensive operative report resulted in a significant improvement in their quality.

A Nationwide Analysis on the Impact of Schizophrenia Following Primary Total Knee Arthroplasty: A Matched-Control Analysis of 49,176 Medicare Patients.

BACKGROUND: The influence of schizophrenia on total knee arthroplasty (TKA) is limited in the literature. Therefore, the purpose of this study was to investigate whether patients with schizophrenia undergoing primary TKA have (1) longer in-hospital length of stay (LOS); (2) higher readmission rates; (3) higher medical complications; (4) higher implant-related complications; and (5) higher costs of care compared to controls. METHODS: Patients with schizophrenia undergoing primary TKA were identified within the Medicare claims database. The study group was randomly matched in a 1:5 ratio to controls according to age, sex, and medical comorbidities. The query yielded 49,176 patients with (n = 8,196) and without (n = 40,980) schizophrenia undergoing primary TKA. Primary outcomes analyzed included in-hospital LOS, 90-day readmission rates, 90-day medical complications, 2-year implant-related complications, in addition to day of surgery and 90-day costs of care. A P-value less than .01 was considered statistically significant. RESULTS: Schizophrenia patients had longer in-hospital LOS (3.73 days vs 3.22 days, P < .0001) and had higher incidence and odds ratios (ORs) of readmission rates (18.26 vs 12.07%; OR: 1.58, P < .0001) compared to controls. Schizophrenia patients had higher incidence and odds of medical (3.23 vs 1.10%; OR: 2.99, P < .0001) and implant-related complications (5.92 vs 3.59%; OR: 1.68, P < .0001) and incurred significantly higher day of surgery ($13,300.58 vs $11,681.77, P < .0001) and 90-day costs of care ($18,222.18 vs $14,845.64, P < .0001). CONCLUSION: This study demonstrates that patients with schizophrenia have longer in-hospital LOS, higher readmission rates, higher complications, and increased costs of care after primary TKA.

Opioid Disorders Are Associated With Thromboemboli Following Primary Total Knee Arthroplasty.

BACKGROUND: Opioid use disorder (OUD) is defined as a problematic pattern of opioid abuse and dependency leading to problems or distress. The purpose of this study is to investigate whether OUD patients undergoing primary total knee arthroplasty (TKA) have higher rates of venous thromboembolisms (VTEs), readmissions, and costs of care. METHODS: Patients undergoing TKA with OUD were identified and matched to controls in a 1:4 ratio according to age, gender, comorbidity index, and comorbidities within the Medicare database. Ninety-day VTEs, 90-day readmissions, and costs of care were compared. A P-value less than .01 was considered statistically significant. RESULTS: The study yielded 54,480 patients with (n = 10,929) and without (n = 43,551) OUD undergoing primary TKA. Matching was successful as there were no significant differences in baseline characteristics. OUD patients were found to have greater odds of VTEs (odds ratio 2.27, P < .0001) 90 days following primary TKA. OUD patients were found to have greater odds of 90-day readmissions (odds ratio 1.39, P < .0001) in addition to incurring higher day of surgery ($13,360.73 vs $11,911.94, P < .0001) and 90-day costs ($18,380.89 vs $15,565.57, P < .0001) compared to controls. CONCLUSION: After adjusting for confounders, this analysis of 54,480 patients identified that patients with OUD have higher rates of VTEs, readmissions, and costs following primary TKA. In addition to using these data to help educate and counsel patients, the study should be used to help further regulate and control opioid prescriptions written by healthcare professionals.

Comparison of implant related complications amongst patients with opioid use disorder and non-users following total knee arthroplasty.

BACKGROUND: The influence of opioid use disorder on implant related complications, infection and readmission rates, and total global episode-of-care costs following primary total knee arthroplasty (TKA) is limited. AIM: To examine whether opioid abuse in patients undergoing primary TKA. METHODS: A retrospective analysis of the Medicare dataset, using the PearlDiver database, from 2005-2014 comparing outcomes in patients with opioid abusers (OUD) to non-opioid abusers (NOU) undergoing primary TKA was performed. Patient outcomes were analyzed including implant complications, readmission rates, and day-of-surgery and 90-d cost. Statistical analysis was performed with R (University of Auckland, New Zealand) calculating odds-ratio (OR) along with their respective 95% confidence interval (95%CI) and P-values. RESULTS: The OUD group was at greater odds of having implant related complications overall (20.84% vs 11.25%; OR: 2.07; 95%CI: 1.93-2.23; P < 0.001). Revision (OR: 2.07; 95%CI: 1.11-3.84; P < 0.001), infection (OR: 1.92; 95%CI: 1.72-2.18; P < 0.001), periprosthetic fractures (OR: 1.83; 95%CI: 1.16-4.79; P < 0.001), and 90-d readmission rates (OR: 1.47, 95%CI: 1.35-1.61, P < 0.001) were also significantly increased. OUD patients also incurred in higher day-of-surgery and total global 90-d episode-of-care costs compared to NOU. CONCLUSION: Patients with OUD show an increased risk of complications compared to the non-opioid users group. Appropriate recognition, pre-surgical optimization, and patient education are essential to mitigate these complications and improve patient outcome.

The Impact of Medical Comorbidities on Primary Total Knee Arthroplasty Reimbursements.

Medical comorbidities have been shown to cause an increase in peri-and postoperative complications following total knee arthroplasty (TKA). However, the increase in cost associated with these complications has yet to be determined. Factors that influence cost have been of great interest particularly after the initiation of bundled payment initiatives. In this study, we present and quantify the influence of common medical comorbidities on the cost of care in patients undergoing primary TKA. A retrospective level of evidence III study was performed using the PearlDiver supercomputer to identify patients who underwent primary TKA between 2007 and 2015. Patients were stratified by medical comorbidities and compared using analysis of variance for reimbursements for the day of surgery and over 90 days postoperatively. A cohort of 137,073 US patients was identified as having undergone primary TKA between 2007 and 2015. The mean entire episode-of-care reimbursement was $23,701 (range: $21,294-26,299; standard deviation [SD] $2,611). The highest reimbursements were seen in patients with chronic obstructive pulmonary disease (mean $26,299; SD $3,030), hepatitis C (mean $25,662; SD $2,766), morbid obesity (mean $25,450; SD $2,154), chronic kidney disease (mean $25,131, $3,361), and cirrhosis (mean $24,890; SD $2,547). Medical comorbidities significantly impact reimbursements, and therefore cost, after primary TKA. Comprehensive preoperative optimization for patients with medical comorbidities undergoing TKA is highly recommended and may reduce perioperative complications, improve patient outcome, and ultimately reduce cost.

Trends in total ankle arthroplasty and revisions in the Medicare database.

BACKGROUND: High failure rates and unacceptable patient outcomes have kept total ankle arthroplasty (TAA) from becoming a favorable treatment option. Modern prosthetic designs and techniques have improved outcomes and decreased revision rates. Current literature has not adequately investigated the recent trends in TAA utilization and revision rate. The purpose of this study was to determine the trends in TAA utilization and the rate of revision TAA by analyzing a comprehensive Medicare database for procedures performed between 2005 and 2012. METHODS: A retrospective review of a comprehensive Medicare database within the PearlDiver Supercomputer application (Warsaw, IN) of the index procedures TAA and revision TAA was conducted. Patients who underwent TAA and revision TAA were identified by Current Procedural Terminology (CPT)-27702, 27703, and International Classification of Disease ninth revision (ICD) codes 81.56, 81.59 respectively. The primary outcomes of this study were annual revision incidence and TAA annual utilization. Demographic data such as age, gender, and geographical location of patients were also examined. RESULTS: Within our study period of 2005-2012 there was a reported total of 7,181 TAAs and 1,431 revision TAAs which is a revision incidence of 19.928% amongst the Medicare population. The compound annual growth rate (CAGR) was 16.37% for TAA, 7.74% for revision TAA, and a mean 7.41% annual revision incidence. Amongst females there were 3,568 TAA and 731 revision TAA compared with 3,336 TAA and 613 revision TAA amongst males. The greatest amount of TAA and revision TAA were found in the 65-69 age group followed by the 70-74 age group. Regionally, the highest number of TAA and revision TAA were found in the South and the lowest in the Northeast. CONCLUSIONS: Our analysis of the Medicare database shows that there is a high rate of annual growth in TAA utilization (16.37%) and revision TAA (7.74%) indicating that there is an increased demand for TAA in the Unites States. However, failed TAA can have serious consequence and revision TAA remains to have suboptimal results. This study highlights the recent trends in ankle arthroplasty and serves to increase awareness of this increasingly popular procedure.

Hypothyroidism Increases 90-Day Complications and Costs Following Primary Total Knee Arthroplasty.

BACKGROUND: Thyroid disease is common and often remains undetected in the US population. Thyroid hormone has an array of metabolic, immunologic, and musculoskeletal functions crucial to well-being. The influence of thyroid disease on perioperative outcomes following primary total knee arthroplasty (TKA) is poorly understood. We hypothesized that hypothyroidism was associated with a higher risk of postoperative complications and 90-day costs following primary TKA. METHODS: The Medicare standard analytical files were queried using International Classification of Disease codes between 2005 and 2014 to identify patients undergoing primary TKA. Patients with a diagnosis of hypothyroidism were matched by age and gender on a 1:1 ratio. Ninety-day postoperative complication rates, day of surgery, and 90-day global period charges and reimbursements were compared between matched cohorts. RESULTS: A total of 2,369,594 primary TKAs were identified between 2005 and 2014. After age and gender matching, each cohort consisted of 98,555 patients. Hypothyroidism was associated with greater odds of postoperative complications compared to matched controls (odds ratio 1.367, 95% confidence interval 1.322-1.413). The 90-day incidence of multiple postoperative medical and surgical complications, including periprosthetic joint infection, was higher among patients with hypothyroidism. Day of surgery and 90-day episode of care costs were significantly higher in the hypothyroidism cohort. CONCLUSION: This study demonstrated an increased risk of multiple postoperative complications and higher costs among patients with hypothyroidism following primary TKA. Surgeons should counsel patients on these findings and seek preoperative optimization strategies to reduce these risks and lower costs in this patient population.

The Impact of Discharge Disposition on Episode-of-Care Reimbursement After Primary Total Hip Arthroplasty.

BACKGROUND: Total joint arthroplasty (TJA) accounts for more Medicare expenditure than any other inpatient procedure. The Comprehensive Care for Joint Replacement model was introduced to decrease cost and improve quality in TJA. The largest portion of episode-of-care costs occurs after discharge. This study sought to quantify the cost variation of primary total hip arthroplasty (THA) according to discharge disposition. METHODS: The Medicare and Humana claims databases were used to extract charges and reimbursements to compare day-of-surgery and 91-day postoperative costs simulating episode-of-care reimbursements. Of the patients who underwent primary THA, 257,120 were identified (204,912 from Medicare and 52,208 from Humana). Patients were stratified by discharge disposition: home with home health, skilled nursing facility, or inpatient rehabilitation facility. RESULTS: There is a significant difference in the episode-of-care costs according to discharge disposition, with discharge to an inpatient rehabilitation facility the most costly and discharge to home the least costly. CONCLUSION: Postdischarge costs represent a sizeable portion of the overall expense in THA, and optimizing patients to allow safe discharge to home may help reduce the cost of THA.

Medical Comorbidities Impact the Episode-of-Care Reimbursements of Total Hip Arthroplasty.

BACKGROUND: Total hip arthroplasty (THA) costs are a source of great interest in the currently evolving health care market. The initiation of a bundled payment system has led to further research into costs drivers of this commonly performed procedure. One aspect that has not been well studied is the effect of comorbidities on the reimbursements of THA. The purpose of this study was to determine if common medical comorbidities affect these reimbursements. METHODS: A retrospective, level of evidence III study was performed using the PearlDiver supercomputer to identify patients who underwent primary THA between 2007 and 2015. Patients were stratified by medical comorbidities and compared using the analysis of variance for reimbursements of the day of surgery, and over the 90-day postoperative period. RESULTS: A cohort of 250,343 patients was identified. Greatest reimbursements on the day of surgery were found among patients with a history of cirrhosis, morbid obesity, obesity, chronic kidney disease (CKD) and hepatitis C. Patients with cirrhosis, hepatitis C, chronic obstructive pulmonary disease, atrial fibrillation, and CKD incurred in the greatest reimbursements over the 90-day period after surgery. CONCLUSION: Medical comorbidities significantly impact reimbursements, and inferentially costs, after THA. The most costly comorbidities at 90 days include cirrhosis, hepatitis C, chronic obstructive pulmonary disease, atrial fibrillation, and CKD.

Comorbidity effects on shoulder arthroplasty costs analysis of a nationwide private payer insurance data set.

BACKGROUND: The purpose of this study was to evaluate the effect of common medical comorbidities on the reimbursements of different shoulder arthroplasty procedures. METHODS: We conducted a retrospective query of a single private payer insurance claims database using PearlDiver (Warsaw, IN, USA) from 2010 to 2014. Our search included the Current Procedural Terminology codes and International Classification of Diseases, Ninth Revision codes for total shoulder arthroplasty (TSA), hemiarthroplasty, and reverse shoulder arthroplasty (RSA). Medical comorbidities were also searched for through International Classification of Diseases codes. The comorbidities selected for analysis were obesity, morbid obesity, hypertension, smoking, diabetes mellitus, hyperlipidemia, atrial fibrillation, chronic obstructive pulmonary disease, cirrhosis, depression, and chronic kidney disease (excluding end-stage renal disease). The reimbursement charges of the day of surgery, 90-day global period, and 90-day period excluding the initial surgical day of each comorbidity were analyzed and compared. Statistical analysis was conducted through analyses of variance or Kruskal-Wallis test. RESULTS: Comorbidities did not have a significant effect on same-day reimbursements but instead caused a significant effect on the subsequent 89-day (interval) and 90-day reimbursements in the TSA and RSA cohorts. For TSA and RSA, the highest reimbursement costs during the 90-day period after surgery were seen with the diagnosis of hepatitis C, followed by atrial fibrillation and later chronic obstructive pulmonary disease. For hemiarthroplasty, the same was true in the following order: hepatitis C, cirrhosis, and atrial fibrillation. CONCLUSION: Shoulder arthroplasty reimbursements are significantly affected by comorbidities at time intervals following the initial surgical day.

Season of the year influences infection rates following total hip arthroplasty.

AIM: To research the influence of season of the year on periprosthetic joint infections. METHODS: We conducted a retrospective review of the entire Medicare files from 2005 to 2014. Seasons were classified as spring, summer, fall or winter. Regional variations were accounted for by dividing patients into four geographic regions as per the United States Census Bureau (Northeast, Midwest, West and South). Acute postoperative infection and deep periprosthetic infections within 90 d after surgery were tracked. RESULTS: In all regions, winter had the highest incidence of periprosthetic infections (mean 0.98%, SD 0.1%) and was significantly higher than other seasons in the Midwest, South and West (P < 0.05 for all) but not the Northeast (P = 0.358). Acute postoperative infection rates were more frequent in the summer and were significantly affected by season of the year in the West. CONCLUSION: Season of the year is a risk factor for periprosthetic joint infection following total hip arthroplasty (THA). Understanding the influence of season on outcomes following THA is essential when risk-stratifying patients to optimize outcomes and reduce episode of care costs.