Excellent 10-Year survivorship of robotic-arm-assisted unicompartmental knee arthroplasty.

Introduction: Robotic-arm-assisted unicompartmental knee arthroplasty (UKA) is an excellent solution for patients suffering from single-compartment knee arthritis. While outcomes tend to be favorable for UKAs, revision operations, commonly due to component malpositioning and malalignment resulting in accelerated wear, are a major concern. Intraoperative technologies, such as robotic assistance, can help better ensure that implants are positioned based on a patient's specific anatomy and mechanical physiology. However, long-term survivorship and patient-reported satisfaction with robotic-assisted UKAs are limited. Therefore, the purpose of this study was to assess the 10-year outcomes of patients who underwent robotic-arm-assisted unicompartmental knee arthroplasty. Specifically, we evaluated: 1) 10-year survivorships; 2) patient satisfaction scores; and 3) re-operations. Methods: From a single surgeon and single institution, 185 patients who had a mean age of 65 years (range, 39 to 92) and a mean body mass index of 31.6 (range, 22.4 to 39) at a mean of 10 years follow-up were evaluated (range, 9 to 11). For all patients, the same robotic-assistive device was utilized intraoperatively, and all patients underwent standardized physical therapy and received standardized pain control management. Then 10-year survivorships with Kaplan-Meir curves, patient satisfaction evaluations with a 5-point Likert scale, and re-operations were assessed as primary outcomes. Results: Overall implant survivorship was 99%, with only two patients requiring revision surgery. There was one patient who was converted to a total knee arthroplasty, while the other patient underwent polyethylene exchange at 5 weeks for an acute infection with successful implant retention. Overall, 97% of the patients were satisfied with their postoperative outcomes, with 81% of patients reporting being very satisfied. There were two other patients who required arthroscopic intervention: one to remove a cement loose body, the other to remove adhered scar from the fat pad and the anterior cruciate ligament. Conclusion: This study is one of the first to provide longer-term (mean 10-year) survivorship and patient-reported satisfaction outcomes for robotic-assisted UKA patients. These data show strong support for utilizing this surgical technique, as nearly all patients maintained their original prostheses and reported being satisfied after a mean of 10 years. Therefore, based on these results, we recommend the use of robotic assistance when performing UKAs.

Robotic-Arm Assisted Lateral Unicompartmental Knee Arthroplasty: Case Series with Minimum Five-Year Follow-Up.

INTRODUCTION: Lateral unicompartmental knee arthroplasty has been shown to be a successful treatment modality for isolated lateral osteoarthritis (OA) of the knee. The reproduction of proper knee kinematics, limb alignment, as well as proper soft tissue balancing and component positioning have been shown to be of the utmost importance for a successful unicompartmental knee arthroplasty (UKA). Robotic assistance has shown to be a reliable tool in order to replicate these factors, as compared to manual instrumentation alone. Recent studies have shown the potential of robotic-assisted surgery in controlling these surgical factors for medial UKA; however, studies assessing outcomes of robotic-assisted lateral UKA (RAUKA) are lacking. Therefore, a retrospective single-center study was performed to assess outcomes of lateral RAUKA. MATERIALS AND METHODS: Patients who underwent lateral RAUKA from a single surgeon at a central institution between January 2008 and June 2017 were identified. All patients received a lateral UKA with a fixed-bearing metal backed onlay tibial component. Patients over the age of 18, with at least a five-year follow-up and a lateral UKA were contacted by phone and asked a series of questions to determine satisfaction and survivorship. Each patient was asked in a "yes" or "no" manner, if they have had their implant revised or reoperated for any reason, and a 5-point Likert scale was used to assess satisfaction. RESULTS: Data was collected from 50 patients (53 knees). Of the patients that responded: 32 (60%) were right knees; 32 (60%) were female, and average follow-up was 7.6 years (5-14 years). Of the 53 knees, one had a revision (98% survivorship). Excluding the revision, 51 (98%) of the included cases were either "very satisfied" or "satisfied" with their surgery. DISCUSSION/CONCLUSIONS: Robotic-arm assisted lateral UKA was found to have high survivorship and a satisfaction rate in patients that had at least a five-year follow-up. In the future, larger prospective comparison studies with longer follow-ups are necessary to adequately compare survivorship and satisfaction rates of robotic-assisted lateral UKA to conventional UKA.

Mako™ Robotic-Arm Assisted Medial Unicompartmental Knee Arthroplasty: Surgical Technique from the Office to the Operating Room.

The utilization of robotic-arm assisted unicompartmental knee arthroplasty (UKA) or partial knee arthroplasty (PKA) for the treatment of medial unicompartmental osteoarthritis has continued to increase. This is in part due to the consistently reproducible accuracy and precision of implant planning, intra-operative ligament balancing software, tracking optimization software, robotic-arm assisted bone preparation, excellent survivorship rates, and improvements in many patient-reported outcomes compared to manual UKA, using the Stryker Mako™ Robotic Partial Knee System (Stryker, Mako Surgical Corp., Mahwah, New Jersey). Training in the utilization of robotic-arm assistance can be time-consuming and comes with an associated learning curve even after the in-person training and coursework is complete, like most procedures. Therefore, our aim was to describe the pre-operative planning and intra-operative surgical technique for using a robotic-arm assisted partial knee system for UKA/PKA in patients who have unicompartmental medial knee osteoarthritis. Specifically, we will discuss: 1) pre-operative planning; 2) operative setup; 3) intra-operative steps; 4) execution of the plan; and 5) trialing, implantation, and final assessments.

Medial Varus Proximal Tibial Resection is Superior to Pie-Crusting of the Medial Collateral Ligament During Primary Total Knee Arthroplasty.

BACKGROUND: Medial varus proximal tibial (MPT) resection or soft tissue releases (STRs) of the medial collateral ligament (MCL) in the form of pie-crusting can be performed to achieve a balanced knee in a varus deformity. Studies comparing the 2 modalities have not been addressed within the literature. Therefore, the aims of this study were to assess the following: (1) compartmental changes between the 2 methods and (2) changes in patient-reported outcome measurements. METHODS: Using our institution's total joint arthroplasty registry, patients who underwent primary total knee arthroplasty from January 1, 2017, to December 31, 2019, were identified. The MPT resection and STR patients were 1:1 matched with baseline parameters yielding 196 patients. Outcomes of interest included: changes in compartmental pressures at 10, 45, and 90° degrees and change to the Short-Form 12, Western Ontario and McMaster Universities Osteoarthritis Index, and Forgotten Joint Scores (FJSs) at the 2-year follow-up period. A P value less than .05 was used as our threshold for statistical difference. RESULTS: The MPT resection led to significant reductions in compartmental pressures at 10° [43 versus 19 pounds (lbs.), P < .0001], 45° (43 versus 27 lbs., P < .0001), and 90° degrees (27 versus 16 lbs., P < .0001) compared to STR. MPT resection also had significantly improved Short-Form 12 (47 versus 38, P < .0001), Western Ontario and McMaster Universities Osteoarthritis Index (9 versus 21, P < .0001), and Forgotten Joint Score (79 versus 68, P = .005). CONCLUSION: Bone modification was superior to pie-crusting of the MCL in achieving consistent pressure balancing and improved outcomes. The investigation can guide surgeons on the preferred method to achieve a well-balanced knee.

Mid-Term Survivorship, Radiographic and Functional Outcomes of Robotic-Assisted Unicompartmental Knee Arthroplasty.

INTRODUCTION: The use of robotic-arm assistance for medial unicompartmental knee arthroplasty (RAUKA) has become an area of interest to overcome technical challenges, improve accuracy, and optimize patient outcomes. Due to the rise in osteoarthritis (OA) and robotic assistance, well-powered long-term studies are warranted. The aim of this study was to analyze midterm survivorship, radiographic changes, range of motion (ROM), and patient-reported outcome measurements (PROMs) of RAUKA. MATERIALS AND METHODS: Patients who underwent RAUKA for medial compartmental OA were identified from April 2009 to May 2014. The query yielded 162 knees with a mean follow up of 6.5 years. Primary endpoints were to compare survivorship, final mechanical axis alignment, radiographic changes, mean ROM, and changes to the following PROMs: Knee Society Score (KSS), International Knee Documentation Committee (IKDC), and Oxford Knee Score (OKS). Statistical analyses were primarily descriptive. A p-value less than 0.05 was considered statistically significant. RESULTS: There were no revisions of the primary implant, one case required exchange of polyethylene bearing and debridement for deep infection, and five cases required additional surgical intervention with implant retention. Overall survivorship was 100%. Radiographic assessment demonstrated no mechanical loosening or osteolysis surrounding the implant. Mean ROM was 3 to 121.9º. Patients demonstrated a mean functional KSS of 78.55, IKDC of 78.22, and OKS of 43.94. CONCLUSIONS: The study supports excellent mid-term outcomes in patients undergoing RAUKA for medial compartment OA. Longer term follow-up studies are necessary to determine the efficacy of this technology for patients undergoing RAUKA for medial compartment OA.

How does sleep apnea impact outcomes following primary total hip arthroplasty for femoral neck fractures: a matched-control analysis.

BACKGROUND: Cross-sectional studies have demonstrated that the prevalence of sleep apnea (SA) to be increasing within the United States. While studies have shown the association of SA and its association on complications following elective orthopedic procedures, well-powered studies investigating its impact in a traumatic setting are limited. The purpose of this study was to determine whether SA patients undergoing primary total hip arthroplasty (THA) for femoral neck fractures have higher rates of: (1) hospital lengths of stay (LOS); (2) readmissions; (3) complications; and (4) healthcare expenditures. METHODS: The 100% Medicare Standard Analytical Files was queried from 2005 to 2014 for patients who sustained femoral neck fractures and were treated with primary THA. The study group consisted of patients with concomitant diagnoses of SA, whereas patients without SA served as controls. Study group patients were matched to controls in a 1:5 ratio by age, sex, and various comorbid conditions. Demographics of the cohorts were compared using Pearson's chi-squared analyses, and multivariate logistic regression analyses were used to calculate the odds (OR) of the effects of SA on postoperative outcomes. A p value less than 0.006 was considered to be statistically significant. RESULTS: The final query yielded 24,936 patients within the study (n = 4166) and control (n = 20,770) cohorts. SA patients had significantly longer in-hospital LOS (6 vs. 5 days, p < 0.0001) but similar readmission rates (24.12 vs. 20.50%; OR: 1.03, p = 0.476). SA patients had significantly higher frequency and odds of developing medical complications (72.66 vs. 43.85%; OR: 1.57, p < 0.0001), and higher healthcare costs ($22,743.79 vs. $21,572.89, p < 0.0001). CONCLUSION: SA is associated with longer in-hospital LOS, higher rates of complications and healthcare expenditures. This study is vital as it can allow orthopaedists to educate patients with SA on the potential complications which may occur following their procedure. LEVEL OF EVIDENCE: III.

Do Patients with Paget's Disease Have Worse Outcomes following Primary Total Knee Arthroplasty?

Well-powered studies evaluating the effects of Paget's disease on patient outcomes following primary total knee arthroplasty (TKA) are limited. The objective of this study was to determine whether Paget's disease patients undergoing primary TKA have higher rates of complications. A query of an administrative database was performed identifying Paget's disease patients undergoing primary TKA as the study cohort. Patients who did not have Paget's disease served as a matching cohort. Study group patients were matched in a 1:5 ratio by age, sex, and comorbidities. The query yielded 34,284 patients in the study (n = 5,714) and matched (n = 28,570) cohorts. Outcomes analyzed included length of stay (LOS), costs of care, 90-day medical and surgical complications, and 2-year implant-related complications. Multivariate logistic regression analyses were used to calculate the odds ratios (ORs) of complications. Paget's disease patients undergoing primary TKA were found to have significantly longer in-hospital LOS (4 vs. 3 days, p < 0.0001). Study group patients incurred significantly higher 90-day episode-of-care costs ($15,124.55 vs. $14,610.01, p < 0.0001). Additionally, Paget's disease patients were found to have higher incidences and odds of medical/surgical (25.93 vs. 13.58%; OR: 1.64, p < 0.0001) and implant-related complications (8.97 vs. 5.02%; OR: 1.71, p < 0.0001). Specifically, Paget's disease patients were more likely to have periprosthetic fractures, mechanical loosening, and revision TKAs (p < 0.0001). This study demonstrated that Paget's disease was associated with longer in-hospital LOS, increased costs, and higher rates of complications. The study can be utilized by physicians to adequately educate patients with Paget's disease concerning potential complications following their primary TKA.

Opioid Use Disorder in Patients Undergoing Primary 1- to 2-Level Anterior Cervical Discectomy and Fusion Is Associated With Longer In-Hospital Lengths of Stay and Higher Rates of Readmissions, Complications, and Costs of Care.

STUDY DESIGN: Retrospective study. OBJECTIVE: To determine whether opioid use disorder (OUD) patients undergoing 1- to 2-level anterior cervical discectomy and fusion (1-2ACDF) have higher rates of: 1) in-hospital lengths of stay (LOS); 2) readmissions; 3) complications; and 4) costs. METHODS: OUD patients undergoing primary 1-2ACDF were identified within the Medicare database and matched to a control cohort in a 1:5 ratio by age, sex, and medical comorbidities. The query yielded 80,683 patients who underwent 1-2 ACDF with (n = 13,448) and without (n = 67,235) OUD. Outcomes analyzed included in-hospital LOS, 90-day readmission rates, 90-day medical complications, and costs. Multivariate logistic regression analyses were used to calculate odds-ratios (OR) for medical complications and readmissions. Welch's t-test was used to test for significance for LOS and cost between the cohorts. An alpha value less than 0.002 was considered statistically significant. RESULTS: OUD patients were found to have significantly longer in-hospital LOS compared to their counterparts (3.41 vs. 2.23-days, P < .0001), in addition to higher frequency and odds of requiring readmissions (21.62 vs. 11.57%; OR: 1.38, P < .0001). Study group patients were found to have higher frequency and odds of developing medical complications (0.88 vs. 0.19%, OR: 2.80, P < .0001) and incurred higher episode of care costs ($20,399.62 vs. $16,812.14, P < .0001). CONCLUSION: The study can help to push orthopaedic surgeons in better managing OUD patients pre-operatively in terms of safe discontinuation and education of opioid drugs and their effects on complications, leading to more satisfactory outcomes.

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.

Iron deficiency anemia is associated with increased medical and implant-related complications and length of stay for patients undergoing total shoulder arthroplasty.

BACKGROUND: Iron deficiency anemia (IDA) is associated with decreased bone mineral density and osteoporosis; however, studies investigating the effects of IDA in patients undergoing primary total shoulder arthroplasty (TSA) have not been well studied. The purpose of this study is to utilize a nationwide administrative claims database to investigate whether patients with diagnosed IDA undergoing primary TSA have higher rates of 1) in-hospital length of stay (LOS); 2) medical complications; and 3) implant-related complications. METHODS: A retrospective review from 2005 to 2014 was conducted using the Medicare Standard Analytical Files. Patients with IDA undergoing primary TSA were identified and matched to controls without IDA, in a 1:5 ratio by age, sex, and medical comorbidities. Outcomes analyzed included in-hospital LOS and 90-day medical and implant-related complications. Mann-Whitney U tests compared in-hospital LOS, and multivariate logistic regression was used to calculate odds ratios (ORs) on the effects of IDA on postoperative complications after adjusting for age, sex, and Elixhauser Comorbidity Index. RESULTS: A total of 17,689 patients with IDA and 88,445 without IDA participated in the matched-cohort analysis, with no differences in age, gender, and comorbidities (P = .99). IDA patients were found to have significantly longer in-hospital LOS (3-days vs. 2-days, P < .0001). IDA patients were also found to have significantly higher odds of 90-day implant-related complications (OR: 1.65, P < .0001), such as periprosthetic joint infections (OR: 1.80, P < .0001) and 90-day medical complications (OR: 2.87, P < .0001), including blood transfusions (OR: 10.37, P < .0001). CONCLUSION: Patients with IDA undergoing primary TSA have significantly longer in-hospital LOS, and medical and implant-related complications. Patients were 10 times more likely to undergo a blood transfusion and 2 times more likely to have a periprosthetic fracture.

Alcohol Abuse, Morbid Obesity, Depression, Congestive Heart Failure, and Chronic Pulmonary Disease are Risk Factors for 90-Day Readmission After Arthroscopic Rotator Cuff Repair.

Purpose: The purpose of this study was to report the rate and causes of 90-day readmissions after arthroscopic rotator cuff repair. Methods: A retrospective query from January 2005 to March 2014 was performed using a nationwide administrative claims registry. Patients and complications were identified using International Classification of Disease, Ninth Revision (ICD-9) and Current Procedural Terminology (CPT) codes. Patients who underwent arthroscopic rotator cuff repair (RCR) and were readmitted within 90 days after their index procedure were identified. Patients not readmitted represented controls. Patients readmitted were stratified into separate cohorts depending on the primary cause of readmission, which included cardiac, endocrine, hematological, infectious, gastrointestinal, musculoskeletal (MSK), neoplastic, neurological or psychiatric, pulmonary, and renal. Risk factors assessed were comorbidities comprising the Elixhauser-Comorbidity Index (ECI). Primary outcomes analyzed and compared included cause for readmission, patient demographics, risk factors, in-hospital length of stay (LOS), and costs. Pearson's chi-square was used to compare patient demographics, and multivariate binomial logistic regression was used to calculate odds ratios (OR) on patient-related risk factors for 90-day readmissions. Results: 10,425 readmitted patients and 301,625 control patients were identified, representing a 90-day readmission rate of 3.5%. The causes of readmissions were primarily related to infectious diseases (15%), MSK (15%), and cardiac (14%) complications. The most common MSK readmissions were osteoarthrosis of the leg or shoulder (24.8%) and spinal spondylosis (8.4%). Multivariate binomial logistic regression analyses demonstrated patients with alcohol abuse (OR, 1.42; P < .0001), morbid obesity (OR, 1.38; P < .0001), depression (OR, 1.35; P < .0001), congestive heart failure (OR, 1.34; P < 0.0001), and chronic pulmonary disease (OR, 1.28; P < .0001) were at the greatest risk of readmissions after RCR. Conclusions: Significant differences exist among patients readmitted, and those patients who do not require hospital readmission within 90 days following arthroscopic rotator cuff repairs. Readmissions are associated with significant patient comorbidities and were primarily related to medically based complications. Level of Evidence: Level III, prognostic, retrospective cohort study.

Implant-related complications in patients with opioid use disorder undergoing primary shoulder arthroplasties: a matched-controlled analysis.

Background: The purpose of this study was to investigate whether patients undergoing primary shoulder arthroplasty with opioid use disorder have higher rates of (1) implant-related complications; (2) in-hospital lengths of stay; (3) readmission rates; and (4) costs of care. Methods: Opioid use disorder patients undergoing primary shoulder arthroplasty were queried and matched in a 1:5 ratio to controls by age, sex, and medical comorbidities within the Medicare database. The query yielded 25,489 patients with (n = 4253) and without (n = 21,236) opioid use disorder. Primary outcomes analyzed included: 2-year implant related complications, in-hospital lengths of stay, 90-day readmission rates, and 90-day costs of care. A p value less than 0.01 was considered statistically significant. Results: Opioid use disorder patients had significantly longer in-hospital lengths of stay (3 days vs. 2 days; p < 0.0001) compared to matched controls. Opioid use disorder patients were also found to have higher incidence and odds (OR) of readmission rates (12.84 vs. 7.45%; OR: 1.16, p < 0.0001) and implant-related complications (20.03 vs. 7.95%; OR: 1.82, p < 0.0001). Study group patients also incurred significantly higher 90-day costs of care ($16,918.85 vs. $15,195.37, p < 0.0001). Discussion: This study can be used to help further augment efforts to reduce opioid prescriptions from healthcare providers in shoulder arthroplasty settings.

The association of iron deficiency anemia and perioperative complications following revision total knee arthroplasty.

BACKGROUND: Recent studies show an increase in the prevalence of iron deficiency anemia (IDA) worldwide and a concomitant rise in the number of revision total knee arthroplasty (RTKA). The literature evaluating the association between IDA and perioperative outcomes following RTKA are limited. Therefore, the purpose of this study was to determine whether IDA patients undergoing RTKA have higher rates of (1) in-hospital lengths of stay (LOS), (2) complications; and (3) costs. METHODS: Using International Classification of Disease, Ninth Revision (ICD-9) and Current Procedural Terminology (CPT), a retrospective query was performed from January 1st, 2005 to March 31st, 2014. The inclusion criteria consisted of those patients who have IDA undergoing RTKA. Study group patients were 1:5 ratio matched to a comparison cohort by age, sex, and various comorbidities: coronary artery disease, chronic obstructive pulmonary disease, diabetes mellitus, hyperlipidemia, hypertension, obesity, and tobacco use, yielding a total of 106,534 patients within the study (n = 17,784) and control (n = 88,750) cohorts. Outcomes assessed included: in-hospital LOS, costs of care, and medical complications. Multivariate Logistic regression analyses were used to calculate the odds-ratios (OR) and respective 95% confidence intervals (95%CI). Welch's t-tests were used to compare in-hospital LOS and costs of care. Following Bonferroni-correction, a P-value less than 0.001 was considered statistically significant. RESULTS: IDA patients undergoing RTKA were found to have significantly higher in-hospital LOS (4-days vs. 3-days, P < 0.0001). Additionally, IDA patients were found to have significantly higher odds (OR) of medical complications (OR: 5.29, P < 0.0001) such as: pneumonia (OR: 6.86, P < 0.0001), respiratory failures (OR: 5.95, P < 0.0001), myocardial infarctions (OR: 4.31, P < 0.0001) and other complications. Furthermore, IDA patients incurred significantly higher day of surgery ($16,976.01 vs. $14,515.81, P < 0.0001) and 90-day costs ($22,548.71 vs. $16,819.15, P < 0.0001). CONCLUSION: The study demonstrated IDA patients undergoing RTKA have higher rates of in-hospital LOS, costs of care, and medical complications. Orthopedic surgeons and other healthcare professionals can use this information to adequately educate these patients of the potential complications following their procedure.

Risk Factors for Infections Following Open Reduction and Internal Fixation for Distal Radius Fractures An Analysis of the Medicare Claims Database.

Bulletin of the Hospital for Joint Diseases 2022;80(2):228-33228 Mahmood B, Golub IJ, Ashraf AM, Ng MK, Vakharia RM, Choueka J. Risk factors for infections following open reduction and internal fixation for distal radius fractures: an analysis of the medicare claims database. Bull Hosp Jt Dis. 2022;80(2):228-33. Abstract Background: Infections following open reduction and internal fixation (ORIF) of distal radius fractures (DRFs) are associated with worse outcomes and increasing health care costs. The purpose of this study was to utilize a nationwide administrative claims database to compare patient demo- graphics of patients who did and did not develop infections and identify patient-related risk factors for postoperative infections. METHODS: Using the PearlDiver database, the 100% Medicare Files from 2005 to 2014 were queried. Patients undergoing ORIF for DRF were identified using Current Procedural Terminology (CPT) codes. Inclusion for the study group consisted of patients who developed infection within 90 days after the procedure and were identified us- ing CPT and International Classification of Disease, Ninth Revision (ICD-9) codes. Multivariable binomial logistic regression analyses were performed to calculate the odds (OR) of certain patient comorbidities and their association with infection following ORIF of DRFs. A p-value less than 0.002 was considered statistically significant after Bonfer- roni correction. RESULTS: The query yielded 132,650 patients within the study, 456 who developed surgical site infections (SSI) and 132,194 who did not. Surgical site infections were more commonly found in certain demographics, such as patients under the age of 65 (26.75 vs. 14.73%) and in males (20.83 vs. 14.15%). Multivariate regression analysis further highlighted that certain comorbidities increased odds for infections within 90-days following ORIF for distal radius fractures and those included: morbid obesity (OR: 2.06, p < 0.0001), depression (OR: 1.92, p = 0.0002), and pathologic weight loss (OR: 1.49, p = 0.001). CONCLUSION: The study found statistically significant dif- ferences between patients who developed and did not develop infection. These findings may help orthopedic surgeons to educate certain high-risk patients of the potential complica- tions that may occur following surgery.

Sleep Apnea and Postoperative Medical Complications and Health Care Expenditures Following Open Reduction and Internal Fixation of Bimalleolar Ankle Fractures.

INTRODUCTION: Sleep Apnea (SA) is a common sleep disorder that increases postoperative morbidity. There is limited research on how SA influences outcomes following operative fixation of ankle fractures. Therefore, the aim of this study was to determine whether patients who undergo surgical fixation for bimalleolar ankle fractures have higher rates of medical complications and health care expenditures. METHODS: A retrospective review from January 1, 2005 to March 31, 2014 was conducted using the parts A and B Medicare Data from PearlDiver database. Patients with and without SA on the day of the primary open reduction and internal fixation (ORIF) of their bimalleolar ankle fractures were queried using the International Classification of Diseases, Ninth Revision codes. Welch'st-tests were used to compare costs of care. A multivariate binomial logistic regression model was used to calculate the odds ratio (OR) of adverse events. A P-value <.001 was considered statistically significant. RESULTS: There were 20 560 patients (SA = 3150; comparison cohort = 17 410) who underwent ORIF for bimalleolar ankle fractures during the study period. Sleep apnea patients were found to have significantly higher rates and odds of 90-day medical complications (21.42% vs 7.47%, OR: 3.11, P < .0001) and 90-day costs of care ($7213.12 vs $5415.79, P < .0001). CONCLUSION: This research demonstrates an increased risk of postoperative medical complications and health care costs among patients with SA undergoing ORIF for bimalleolar ankle fractures. LEVEL OF EVIDENCE: Therapeutic, Level IV: Retrospective.

A nationwide analysis on the effects of chronic obstructive pulmonary disease following primary total shoulder arthroplasty for glenohumeral osteoarthritis.

Background: Chronic obstructive pulmonary disease patients have been shown in orthopedic literature to have poorer outcomes and higher rates of complications from surgery. In this retrospective review, medical complications, length of stay, and costs were obtained to explore the effects of chronic obstructive pulmonary disease on patients undergoing primary total shoulder arthroplasty. Methods: Total shoulder arthroplasty cases from January 2005 to March 2014 were queried and analyzed from a nationwide database. Study patients were matched 1:5 to controls by age, sex, and medical comorbidities associated with chronic obstructive pulmonary disease. In-hospital length of stay, 90-day medical complications, day of surgery, and total global 90-day episode of care costs were obtained for comparison. Results: Chronic obstructive pulmonary disease patients were found to have higher incidence and odds (53.91 vs. 11.95%; OR: 3.58, 95%CI: 3.18-3.92, p < 0.0001) of 90-day medical complications, longer in-hospital length of stay (3 vs. 2 days, p < 0.0001), and significantly higher 90-day costs ($14,768.37 vs. $13,379.20, p < 0.0001) following primary total shoulder arthroplasty compared to matched controls. Discussion: Chronic obstructive pulmonary disease patients undergoing primary total shoulder arthroplasty have higher rates of medical complications, in-hospital length of stay, and costs of care. This represents an important factor that will allow orthopedic surgeons to adequately manage expectations and educate chronic obstructive pulmonary disease patients of the potential complications which may occur following total shoulder arthroplasty.

Complications, readmission rates, and in-hospital lengths-of-stay in octogenarian vs. non-octogenarians following total knee arthroplasty: An analysis of over 1.7 million patients.

INTRODUCTION: Studies investigating complications between octogenarians and non-octogenarians undergoing primary total knee arthroplasty (TKA) are limited. Therefore, we investigated whether octogenarians are at greater odds of: (1) in-hospital lengths of stay (LOS) (2) readmission rates, (3) medical complications, and (4) hardware complications compared to non-octogenarians following TKA. METHODS: A retrospective query of the PearlDiver database isolated 1,775,460 patients who underwent primary TKA from 2005 to 2014. Patients aged 80 and above represented the study cohort (n = 295,908) and patients 65 to 79 represented the control cohort (n = 1,479,552). Study group patients were matched to controls in a 1:5 ratio according to gender and medical comorbidities. Pearson's Chi Square and logistic regression were used to analyze the primary outcomes of the study which included 90-day medical complications, 90-day readmission rates, 2-year implant-related complications, and in-hospital LOS. A p-value less than 0.001 was statistically significant. RESULTS: Octogenarians were found to have significantly higher incidence and odds of 90-day readmission rates (10.59 vs. 9.35%; OR: 1.15, p < 0.0001) and significantly longer in-hospital LOS (3.69 days ± 1.95 vs. 3.23 days ± 1.83, p < 0.0001) compared to controls. Octogenarians also had equal incidence and odds of developing any medical complication (1.26 vs. 1.26%; OR: 0.99, p = 0.99) and lower incidence and odds (1.67 vs. 1.93%; OR: 0.86, p < 0.001) of implant-related complications compared to controls. CONCLUSION: Octogenarians undergoing primary TKA have similar odds of medical related complications and lower odds of implant-related complications compared to non-octogenarian patients, whereas readmission rates and in-hospital LOS are greater.

The Association of Cannabis Use Disorder and Perioperative Complications After Primary Total Knee Arthroplasty.

INTRODUCTION: Although studies have shown the implications of substance use on total joint arthroplasty, studies investigating the association of patients exclusively who have cannabis use disorder (CUD) after primary total knee arthroplasty (TKA) are sparse. As such, this study analyzed a private payor database to assess the relationship of CUD after primary TKA. METHODS: Data from the Mariner data set were used to identify patients who have CUD undergoing primary TKA. Patients with CUD were ratio matched 1:5 to a comparison population by age, sex, and comorbidities, yielding 55,553 patients in the study (n = 9,260) and case-matched (n = 46,293) population. Variables compared included in-hospital length of stay, complications, and costs. A P value of less than 0.003 was considered statistically significant. RESULTS: Patients with CUD were found to have longer in-hospital length of stay (3.61 versus 2.07 days, P < 0.0001), in addition to higher frequency and odds ratio (OR) of medical (28.08 versus 12.5; OR, 1.50, P < 0.0001) and prostheses-related complications (9.63 versus 5.16%; OR, 1.56, P < 0.0001). Patients with CUD also incurred significantly higher episode of care costs ($29,025.34 versus $24,258.17, P < 0.0001). CONCLUSION: With the continued legalization of cannabis use across the United States, studies investigating the association of cannabis on outcomes after primary TKA are limited. The current study helps to expand the current literature on outcomes of substance abuse after total joint arthroplasty and can serve to help educate patients of potential complications after their TKA.

Increased In-Hospital Lengths of Stay, Readmission Rates, Complications, and Costs in Patients Who Have Depressive Disorders Following Primary Total Hip Arthroplasty.

INTRODUCTION: Recent studies have shown the prevalence of depressive disorders has increased within the United States. Studies investigating the impact of depressive disorders following primary THA are limited. Therefore, the purpose of this study was to determine whether patients with depressive disorders have higher rates of: 1) in-hospital lengths of stay (LOS); 2) readmission rates; 3) medical complications; and 4) implant-related complications. MATERIALS AND METHODS: A retrospective query of the Humana claims database was performed. Patients undergoing primary THA with a history of depressive disorders were identified by International Classification of Disease, Ninth Revision (ICD-9), and Current Procedural Terminology (CPT) codes. Study group patients were matched to controls in a 1:5 ratio by age, sex, and comorbidities. The query yielded 67,245 patients with (n=11,255) and without (n=55,990) depressive disorders. Welch's t-tests were used to test for significance in LOS between the cohorts; whereas, logistics regression analyses were used for complications and readmissions. A p-value less than 0.003 was statistically significant. RESULTS: Patients with depressive disorders undergoing primary THA had significantly longer in-hospital LOS (6.59 days vs. 2.96 days, p <0.0001). Additionally, patients with depressive disorders had higher incidence and odds of readmission rates (46.02 vs. 35.43%; OR: 1.55, p <0.0001), medical complications (7.05 vs. 1.84%; OR: 4.04, p <0.0001), and implant-related complications (5.76 vs. 2.75%; OR: 2.16, p <0.0001) compared to patients without depressive disorders. CONCLUSION: After matching age, sex, and medical comorbidities, the results of the study demonstrate patients with depressive disorders have longer in-hospital LOS and increased rates of complications and readmission rates. The study is useful as it can allow orthopedic surgeons to properly counsel these patients of the potential complications which may arise following their procedure.

Impact of Biological Sex on Complications, Lengths of Stay, Readmission Rates, and Costs of Care Following Primary Total Knee Arthroplasty.

The impact of gender on total knee arthroplasty (TKA) postoperative complications, readmission rates, and costs of care has not been often evaluated. Therefore, the purpose of this study was to investigate which sex had higher rates of: (1) medical complications; (2) implant complications; (3) lengths of stay (LOSs); (4) readmission rates; and (5) costs after TKA. A query was performed using an administrative claims database from January 1, 2005, to March 31, 2015. Patients who had TKAs were identified using International Classification of Diseases, Ninth Revision and Current Procedural Terminology codes. Males and females were filtered separately and matched according to age and various medical comorbidities leading to 1,590,626 patients equally distributed. Primary outcomes analyzed included 90-day medical complications, LOSs, 90-day readmission rates, in addition to day of surgery and total global 90-day episode of care costs. Pearson's chi-square analyses were used to compare medical complications and readmission rates. Welch's t-tests were used to test for significance in matching outcomes and costs. A p-value of less than 0.01 was considered statistically significant. Males had a smaller risk of complications than women (1.35 vs. 1.40%, p < 0.006) and higher rates of implant-related complications (2.28 vs. 1.99%, p < 0.0001). Mean LOSs were lower for males: 3.16 versus 3.34 days (p < 0.0001). The 90-day readmission rates were higher in men (9.67 vs. 8.12%, p < 0.0001). This study demonstrated that males undergoing primary TKA have lower medical complications and shorter LOSs then their female counterparts. However, males have higher implant-related complications, readmission rates, and costs of care.