The Perspectives of Robotic Surgeons.

Given recent advancements in artificial intelligence and robotic surgery, attention has now been paid to the concept of autonomous surgery. As robotic surgery has developed and matured, examples of autonomous surgery have arisen through the assistance of artificial intelligence. As with any new technology, ethical and legal considerations also arise, and there are special considerations that should be taken into account with the adaptation of new technology involving patient care. In this paper, we will describe autonomous surgery used in general surgery and lower extremity joint arthroplasty, and we will highlight the current ethical and legal considerations associated with this technology.

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.

Are Metal Ion Levels Elevated After Dual Mobility Acetabular Systems: Minimum Five-Year Analyses.

INTRODUCTION: While dual mobility systems in total hip replacements have demonstrated reduced dislocation and revision occurrences, concerns persist about the potential elevation of metal ions in the bloodstream, leading to negative tissue reactions. Notably, there's a scarcity of research spanning over five years post-surgery that examines cobalt and chromium levels after such implants. This study aimed to delve into these metal ion concentrations after a five-year period, building on previous metal-ion findings. We focused on: (1) cobalt concentrations in blood and urine; (2) chromium concentrations in blood and urine; (3) cobalt variations based on follow-up duration and specific implant metrics (e.g., offset, cup dimension, stem, and neck inclination); and (4) chromium variations based on the same parameters. MATERIALS AND METHODS: We tracked 57 individuals who received THA using modular dual mobility systems from January 1, 2011, to December 31, 2016, for an average span of six years (ranging from five to 10 years). At the final check-up, we measured cobalt and chromium levels in serum, plasma, blood, and urine. We also evaluated parameters like head composition and dimension, stem offset, cup dimension, and stem-neck inclination. RESULTS: Cobalt concentrations remained minimal, with average blood and urine values being 0.8+0.6mcg/L (standard <1.8mcg/L) and 1.2+1.0mcg/L (standard <2.8mcg/L), respectively. Two individuals exhibited a slight increase in blood cobalt concentration by 0.1 and 0.2mcg/L. Chromium averages in blood and urine were also minimal, with readings of 0.9+0.2mcg/L (standard <1.2mcg/L) and 1.3 + 0.5mcg/L (standard <2mcg/L), respectively. One individual had a marginally increased blood chromium concentration of 1.3mcg/L. Evaluations considering ceramic or cobalt-chrome heads, up to a decade of follow up, or varying implant metrics showed negligible variations in metal ion concentrations. CONCLUSION: The findings reveal that over a minimum of five years (average = six years; span, five to 10 years), cobalt and chromium concentrations in patients' systems remained within normal limits and were clinically insignificant, irrespective of the follow-up duration, head material, or implant specifications. This underscores the efficacy of dual mobility systems in ensuring minimal metal ion presence.

Optimal Method of Skin Wound Management for Total Knee Arthroplasty: A Systematic Review and Meta-Analysis.

Skin closure for total knee arthroplasty (TKA) typically focuses on promoting optimal healing, while preventing wound complications and infection, allowing for functionality and immediate ambulation, and providing for excellent cosmesis. In this systematic review and meta-analysis of the literature, we will focus on closure of the skin. Specifically, we assessed: (1) wound complication risk of different techniques and (2) closing time of different sutures/techniques. There were 20 reports on infection risk and closing time. Meta-analyses focused on the qualifying studies for closing time and wound complication risk reports were also performed. These studies (378 patients) demonstrated overall lower wound complication risks with the use of barbed compared with traditional sutures (3% vs. 6%, p < 0.05). The subsequent meta-analysis included 749 patients demonstrating overall significant closing time reductions of a mean of 7 minutes with the use of barbed sutures (p < 0.05). Therefore, multiple recent reports suggest superior outcomes and faster results when using barbed sutures for TKA skin closure.

Patient-reported and radiographic outcomes of a porous-coated acetabular cup in robotic assisted total hip arthroplasty at 2-year follow up.

Introduction: Several implant manufacturers have developed ultra-porous metal substrate acetabular components recently. Despite this, data on clinical and radiographic outcomes remain limited. Our study evaluated postoperative patient-reported outcome measures (PROMs) and radiographic analyses in patients fitted with a novel acetabular porous-coated component. Methods: A total of 152 consecutive patients underwent a total hip arthroplasty by a single orthopaedic surgeon. All patients underwent surgery utilizing the same CT-scan based robotic-assisted device with the same porous cementless acetabular shell. They received standardized postoperative physical therapy, rehabilitation, and pain protocols. Preoperatively, first postoperative visit, 6-months, 1-year, and 2-years, patients were evaluated based on Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain, physical function, and total scores; 2) Patient-Reported Outcomes Measurement Information System (PROMIS)-10 physical and mental scores; 3) Hip Disability and Osteoarthritis Outcome Score (HOOS)-Jr scores; as well as 4) acetabular component positions and 5) evidence of acetabular component loosening. Results: Significant improvements were observed by 6 months in WOMAC pain, physical function, and total scores (p < 0.05), maintained at 1 and 2 years. PROMIS-10 physical scores also improved significantly from preoperative to 6 months postoperative and remained so at 1 and 2 years postoperative (p < 0.05). No significant changes were found in PROMIS-10 mental scores. HOOS-Jr scores significantly improved from preoperative to 6 months postoperative and remained so through 2 years (p < 0.05). At 6 months, slight changes were noted in abduction angle and horizontal and vertical offset. Radiolucencies, initially found in 3 shells, reduced to 1 shell with 2 new radiolucencies by 6 months, and remained stable with no subsequent operative interventions. At 1 year and 2 years, no radiographic abnormalities were noted, including complete resolution of prior radiolucencies as well as stable components. Conclusion: This porous cementless acetabular shell, implanted with CT-scan-based robotic-assisted techniques, demonstrated excellent postoperative PROMs at 2 years. Stable radiolucencies suggest good component stability. The early stable clinical and radiographic results suggest promising long-term outcomes with this device. Level of evidence: III (retrospective cohort study).

Use of Remote Physiologic and Therapeutic Monitoring Following Total Knee Arthroplasty.

INTRODUCTION: Remote physiologic monitoring (RPM), or remote therapeutic monitoring (RTM), has grown exponentially for the management of chronic medical diseases in Medicare patients. More recently, the application of this technology has ventured into the orthopaedic arena, and more specifically, for total joint arthroplasty. Platforms to expedite this monitoring can provide continuous biodata feedback on digital biomarkers to patients and surgeons, which can potentially help improve and create novel patient-specific recovery pathways. Furthermore, various devices developed for this monitoring might help obviate the need for frequent emergency room visits, readmissions, and prolonged outpatient physical therapy sessions, as well as reduce complications and increase patient satisfaction scores after total joint arthroplasty surgery. However, while there are a number of potential benefits to technology for this type of care, its application following total knee arthroplasty has not been well-studied. Therefore, after an overview of the usage of RPM and RTM, the purpose of this study was to review the current literature regarding three common remote monitoring technologies: 1) smartphone apps; 2) wearables; and 3) combined smartphone apps and wearables. We also considered the potential financial implications of remote physiologic monitoring. MATERIALS AND METHODS: A comprehensive search of the PubMed, Cochrane Library, MedLine, and Web of Science databases was performed. Three main subgroups of monitoring devices were included for analysis: smartphone apps, wearable devices, and combined wearable plus smartphone app platforms. Searches focused on remote physiologic monitoring, patient-specific advantages, financial advantages, billing and coding options, as well as overall efficacy of platforms. RESULTS: The current review found smartphone apps, wearables, and combined smartphone app and wearable platform technologies to be advantageous in the postoperative period following total knee arthroplasty. The wearable components can provide highly accurate and reproducible data, which the user-friendly smartphone app can relay to the patient so they can easily understand their progress. Additionally, through the apps, patients can directly access their surgical team. By constantly collecting and evaluating range of motion and functional data, the surgical team can identify if the patient is appropriately progressing through treatment or if further intervention is warranted. CONCLUSION: The incorporation of the remote physiologic monitoring devices during the post-total knee arthroplasty period shows strong promise as a progress-tracking modality. Published benefits include reduced physical therapy visits, decreased pain scores and reliance on opioids, increased activity levels as assessed by step counts, increased ability to follow less well-performing patients, reduced readmissions, reduced in-person clinic visits, and decreased postoperative costs.

Relationship Between Preoperative Nutritional Status and Predicting Short-Term Complications Following Revision Total Hip Arthroplasty.

BACKGROUND: The association between malnutrition and complications following primary total joint arthroplasty is well-delineated; however, nutritional status has yet to be explored specifically in revision total hip arthroplasty (THA). Therefore, our objective was to examine if a patient's nutritional status based on body mass index, diabetic status, and serum albumin predicted complications following a revision THA. METHODS: A retrospective national database review identified 12,249 patients who underwent revision THA from 2006 to 2019. Patients were stratified based on body mass index (<18.5 = underweight, 18.5-29.9 = healthy/overweight, ≥30 = obese), diagnosis of diabetes (no diabetes, insulin-dependent diabetes mellitus (IDDM), non-insulin-dependent diabetes mellitus), and preoperative serum albumin (<3.5 = malnourished, ≥3.5 = non-malnourished). Multivariate analyses were performed using chi-square tests and multiple logistic regressions. RESULTS: In all groups including underweight (1.8%), healthy/overweight (53.7%), and obese (44.5%), those without diabetes were less likely to be malnourished (P < .001), while those with IDDM had a higher rate of malnutrition (P < .001). Underweight patients were significantly more malnourished compared to healthy/overweight or obese patients (P < .05). Malnourished patients had an increased risk of wound dehiscence/surgical site infections (P < .001), urinary tract infection (P < .001), requiring a blood transfusion (P < .001), sepsis (P < .001), and septic shock (P < .001). Malnourished patients also have worse postoperative pulmonary and renal function. CONCLUSION: Patients who are underweight or have IDDM are more likely to be malnourished. The risk of complications within 30 days of surgery following revision THA significantly increases with malnutrition. This study shows the utility of screening underweight and IDDM patients for malnutrition prior to revision THA to minimize complications.

Early Infection Trends for Primary Total Knee Arthroplasty: A 5-Year Review.

The aim of this study was to track the annual rates and trends of overall, deep, and superficial surgical site infections (SSIs) following total knee arthroplasty using the most recent results from a large and nationwide database. A total of 197,192 cases were performed between 2012 and 2016 from a nationwide database stratified into years and based on superficial and/or deep SSIs. Cohorts were analyzed individually and then combined to evaluate overall SSI rates. The infection incidence for each year was calculated. After a 6-year correlation and trends analysis, univariate analyses were performed to compare the most recent year, 2016, with each of the preceding 4 years. Overall, there was a downward trend in overall SSI rates over the study period (2012-2016, with the lowest rate occurring in the most recent year, 2016 [0.11%]). Additionally, there was a decreasing trend for superficial SSI, with the lowest superficial SSI incidence occurring in 2016 (0.47%) and the greatest incidence occurring in 2012 (0.53%). An overall trend of decreasing SSI rates was observed nationwide over the 5-year period evaluated. A similar decreasing trend was also noted specifically for deep SSI rates, which can be potentially more complicated to manage, and result in decreased implant survivorship. The down trending SSI rates observed give potential credence to the value for newer and developing SSI preventative therapies as well as improved medical and surgical patient management. Nevertheless, there is still room for improvement, and continued efforts are needed to further lower SSIs after total knee arthroplasty.

Dressing Management during Total Knee Arthroplasty: A Systematic Review and Meta-Analysis.

Dressings for total knee arthroplasty (TKA) typically focus on promoting optimal healing, while preventing infection, allowing for functionality and immediate ambulation, while providing for excellent cosmesis. We have previously described four aspects of closure after TKA involving the: (1) deep fascial layer; (2) subdermal layer; (3) intradermal layer, including the subcuticular region; and (4) a specific aseptic dressing. In this meta-analysis and systematic review of the literature, we will focus on the dressing. Specifically, we assessed: (1) infection risk of different techniques; (2) re-operation or readmission risk; and (3) length of time until dressing change needed. There were 16 reports on infection risk, re-operation risk, and length of time until change needed. A meta-analysis focused on the qualifying wound complication risk reports was also performed. The meta-analysis including four studies (732 patients) demonstrated overall lower wound complication risk with the use of adhesives and mesh dressings (odds ratio 0.67) versus traditional closures. Additionally, studies demonstrated fewer re-operations and readmissions with the use of adhesives and mesh dressings. Furthermore, one report demonstrated mesh dressings persist longer than silver dressings. Therefore, multiple recent reports suggest superior outcomes when using adhesive and mesh dressings for TKAs.

What is a better value for your time? Anterior cervical discectomy and fusion versus cervical disc arthroplasty.

Introduction: Compared to anterior cervical discectomy and fusion (ACDF), the motion preservation of cervical disc arthroplasty (CDA) provides an attractive alternative with similar short-term results. However, there is a paucity of the economics of performing CDA over ACDF. Study Design: This was retrospective study. Objective: The objective of this study is to evaluate relative-value-units (RVUs), operative time, and RVUs-per-minute between single-level ACDF and CDA. Secondary outcomes included 30-day readmission, reoperation, and morbidity. Methods: Adults who underwent ACDF or CDA in 2011-2019 National Surgical Quality Improvement Program database datasets. Multivariate quantile regression was utilized. Results: There were 26,595 patients (2024 CDA). ACDF patients were older, more likely to be female, discharged to inpatient rehabilitation, and have a history of obesity, smoking, diabetes, steroid use, and the American Society of Anesthesiologists-class ≥3. ACDF had greater median RVUs-per-case (41.2 vs. 24.1) and RVUs-per-minute (0.36 vs. 0.27), despite greater operative-time (109 min vs. 92 min) (P < 0.001). ACDF predicted a 16.9 unit increase in median RVUs per case (P < 0.001, confidence interval [CI]95: 16.3-17.5), an 8.81 min increase in median operative time per case (P < 0.001, CI95: 5.69-11.9), and 0.119 unit increase in median RVUs-per-minute (P < 0.001, CI95: 0.108-0.130). ACDF was associated with greater unadjusted rates of readmission (3.2% vs. 1.4%) morbidity (2.3% vs. 1.1%) (P < 0.001), but similar rates of reoperation (1.3% vs. 0.8%, P = 0.080). After adjusting for significant patient-related and procedural factors, readmission (odds ratio [OR] = 0.695, P = 0.130, CI95: 0.434-1.113) and morbidity (OR = 1.102, P = 0.688, CI95: 0.685-1.773) was similar between ACDF and CDA. Conclusions: Median RVUs-per-minute increased by 0.119 points for ACDF over CDA, or $257.7/h for each additional-hour of surgery. Adjusted 30-day outcomes were similar between procedures. Reimbursement for CDA does not appear to be in line with ACDF and may be a barrier to widespread usage.

Psoriasis and Post-Surgical Infections in Primary Total Knee Arthroplasty: An Analysis of 10,727 Patients.

BACKGROUND: Psoriasis is a dermatologic condition characterized by erythematous plaques that may increase wound complications and deep infections following total knee arthroplasty (TKA). There is a paucity of evidence concerning the association of this disease and complications after TKA. This study aimed to determine if patients who have psoriasis vs non-psoriatic patients have differences in demographics and various comorbidities as well as post-operative infections, specifically the following: (1) wound complications; (2) cellulitic episodes; and (3) deep surgical site infections (SSIs). METHODS: We identified 10,727 patients undergoing primary TKA utilizing an institutional database between January 1, 2017 and April 1, 2019. A total of 133 patients who had psoriasis (1.2%) were identified using International Classification of Diseases, Tenth Revision codes and compared to non-psoriatic patients. The rate of wound complications, cellulitic episodes, and deep SSIs were determined. After controlling for age and various comorbidities, multivariate analyses were performed to identify the associated risks for post-operative infections. RESULTS: Psoriasis patients showed an increased associated risk of deep SSIs (3.8%) compared to non-psoriasis patients (1.2%, P = .023). Multivariate analyses demonstrated a significant associated risk of deep SSIs (odds ratio 7.04, 95% confidence interval 2.38-20.9, P < .001) and wound complications (odds ratio 4.44, 95% confidence interval 1.02-19.2, P = .047). CONCLUSION: Psoriasis is an inflammatory dermatologic condition that warrants increased pre-operative counseling, shared decision-making, and infectious precautions in the TKA population given the increased risk of wound complications and deep SSIs. Increased vigilance is required given the coexistence of certain comorbidities with this population, including depression, substance use disorder, smoking history, gastroesophageal reflux disease, and inflammatory bowel disease.

Improved Component Placement Accuracy with Robotic-Arm Assisted Total Knee Arthroplasty.

Component position of total knee arthroplasty (TKA) has been shown to influence prosthetic survivorships and clinical outcomes. Our objective was to compare the three-dimensional accuracy to plan of robotic-arm assisted TKA (RATKA) with conventional TKA for component position. We conducted a nonrandomized, prospective study comparing 143 RATKA with 86 conventional TKA operated at four U.S. centers between July 2016 and October 2018. Computed tomography (CT) scans obtained approximately 6 weeks postoperatively were analyzed using anatomical landmarks. Absolute deviation from surgical plans were defined as the absolute value of the difference between the CT measurements and surgeons' femoral and tibial component mechanical varus/valgus alignment, tibial component posterior slope, and femoral component internal/external rotation. Differences of absolute deviations were tested using stratified Wilcoxon's tests that controlled for study center. Patient-reported outcome measures collected through 1 postoperative year were modeled using multiple regression controlling for age, sex, body mass index, study center, and the preoperative score. RATKA demonstrated greater accuracy for tibial component alignment (median [25th, 75th percentiles] absolute deviation from plan of all centers combined for conventional vs. RA, 1.7 [0.9, 2.9] vs. 0.9 [0.4, 1.9] degrees, p < 0.001), femoral component rotation (1.5 [0.9, 2.5] vs. 1.3 [0.6, 2.5] degrees, p = 0.015), and tibial slope (2.9 [1.5, 5.0] vs. 1.1 [0.6, 2.0] degrees, p < 0.001). In multivariable analyses, RATKA showed significantly greater Veterans RAND 12-item health survey (VR-12) physical component scores (adjusted mean difference [95% confidence interval (CI)]: 2.4 [0.2, 4.5] points, p = 0.034) and qualitatively greater Knee Society (KS) composite functional scores (3.5 [-1.3, 8.2] points, p = 0.159), though not statistically significant. Compared with conventional instrumentation, RATKA demonstrated greater three-dimensional accuracy to plan for various component positioning parameters and clinical improvements in physical status and function with no major safety concerns during the first postoperative year. These results may be attributed to the preoperative CT scan planning, real-time intraoperative feedback, and stereotactic-guided cutting that takes into consideration patient-specific bony anatomy. These findings support the use of RATKA for enhanced arthroplasty outcomes.

How Does Robotic-Arm Assisted Technology Influence Total Knee Arthroplasty Implant Placement for Surgeons in Fellowship Training?

Implant malalignment during total knee arthroplasty (TKA) may lead to suboptimal postoperative outcomes. Accuracy studies are typically performed with experienced surgeons; however, it is important to study less experienced surgeons when considering teaching hospitals where younger surgeons operate. Therefore, this study assessed whether robotic-arm assisted TKA (RATKA) allowed for more accurate and precise implant position to plan when compared with manual techniques when the surgery is performed by in-training orthopaedic surgical fellows. Two surgeons, currently in their fellowship training and having minimal RATKA experience, performed a total of six manual TKA (MTKA) and six RATKAs on paired cadaver knees. Computed tomography scans were obtained for each knee pre- and postoperatively. These scans were analyzed using a custom autosegmentation and autoregistration process to compare postoperative implant position with the preoperative planned position. Mean system errors and standard deviations were compared between RATKA and MTKA for the femoral component for sagittal, coronal, and axial planes and for the tibial component in the sagittal and coronal planes. A 2-Variance testing was performed using an α = 0.05. Although not statistically significant, RATKA was found to have greater accuracy and precision to plan than MTKA for: femoral axial plane (1.1° ± 1.1° vs. 1.6° ± 1.3°), coronal plane (0.9° ± 0.7° vs. 2.2° ± 1.0°), femoral sagittal plane (1.5° ± 1.3° vs. 3.1° ± 2.1°), tibial coronal plane (0.9° ± 0.5° vs. 1.9° ± 1.3°), and tibial sagittal plane (1.7° ± 2.6° vs. 4.7° ± 4.1°). There were no statistical differences between surgical groups or between the two surgeons performing the cases. With limited RATKA experience, fellows showed increased accuracy and precision to plan for femoral and tibial implant positions. Furthermore, these results were comparable to what has been reported for an experienced surgeon performing RATKA.

Inpatient dislocation after primary total hip arthroplasty: incidence and associated patient and hospital factors.

INTRODUCTION: Inpatient dislocation following total hip arthroplasty (THA) may incur substantial financial penalties for hospitals in the United States. However, limited studies report on current incidence and variability of dislocations. We utilised a large national database to evaluate inpatient hip dislocation trends regarding: (1) yearly incidences; (2) lengths of stay (LOS); (3) demographic factors; and (4) hospital metrics. METHODS: The National Inpatient Sample was queried from 2012 to2016 for primary THA patients (n = 1,610,155), identifying 2490 inpatient dislocations. Various patient demographics and hospital characteristics were assessed. Multivariate regression analyses were conducted to identify dislocation risk factors. RESULTS: Dislocation rates increased from 0.11% in 2012 to 0.18% in 2016 (p < 0.001). Dislocated patients experienced significantly longer LOS (p < 0.001). Patient demographic factors associated with dislocation were sex, race, Medicaid insurance, alcohol use disorder, psychosis, hemiparesis/hemiplegia, chronic renal failure, and obesity. Spinal fusion was not associated with inpatient dislocation. Dislocations were likeliest in the South and least likely in teaching hospitals. CONCLUSION: Inpatient dislocation has increased in recent years. Optimised management and recognition of the patient and hospital factors outlined in this study may help decrease inpatient dislocation risks following THA, thus avoiding hospital reimbursement penalties for this preventable complication.

Impact of Parkinson's Disease on Complications, Readmission Rates, and Costs of Care following Primary Total Knee Arthroplasty.

Large-scale studies evaluating the effects of Parkinson's disease (PD) on primary total knee arthroplasty (TKA) are limited. The purpose of this study was to determine if PD patients undergoing primary TKA have increased: (1) medical complications; (2) implant-related complications; (3) readmission rates; and (4) costs. A query was performed using an administrative claims database. The study group consisted of all patients undergoing primary TKA who had a history of PD. Matched non-PD patients undergoing primary TKA served as a control group. The query yielded 72,326 patients (PD = 18,082; matching cohort = 54,244). Pearson's chi-square tests, logistic regression analyses, and Welch's t-tests were used to test for significance between the cohorts. Primary TKA patients who had PD were found to have greater incidences and odds of medical complications (4.21 vs. 1.24%; odds ratio [OR]: 3.50, 95% confidence interval [CI]: 3.15-3.89, p < 0.0001) and implant-related complications (5.09 vs. 3.15%; OR: 1.64, 95% CI: 1.51-1.79, p < 0.0001) compared with the matching cohort. Additionally, the rates and odds of 90-day readmission were higher (16.29 vs. 12.66%; OR:1.34, p < 0.0001) and episodes of care costs were significantly greater ($17,105.43 vs. $15,252.34, p < 0.0001) in patients who had PD. Results demonstrate that PD patients undergoing primary TKA had higher incidences of medical and implant-related complications. They also had increased 90-day readmission rates and costs compared with controls. The findings of this study should be used in risk stratification and should inform physician-patient discussion but should not be arbitrarily used to deny access to care.

Intra-Articular Corticosteroid or Hyaluronic Acid Injections Are Not Associated with Periprosthetic Joint Infection Risk following Total Knee Arthroplasty.

This study evaluated whether the preoperative use and timing of the use of hyaluronic acid (HA) and/or corticosteroid (CS) injections were associated with an increased risk of periprosthetic joint infections (PJIs) following primary total knee arthroplasty (TKA). We tested the hypothesis that preoperative injection of HA or CS within 3 months prior to primary TKA was associated with an increased risk of PJI by specifically evaluating the association between PJI risk and (1) injection type; (2) timing; (3) patient demographic factors; and (4) surgery-related factors, such as surgeon injection volume, knee arthroscopy (pre- and postoperative), and hospital length of stay. The 5% Medicare part B claims database was queried for patients who received CS and/or HA injections. Cox proportional hazards regressions evaluated the risk of PJIs after TKA, adjusting for patient and clinical factors, as well as propensity scores. The unadjusted incidence of PJI at 2-year post-TKA was 0.75% for the CS group, 0.89% for the HA group, 0.96% for both CS and HA group, and 0.75% for those who did not use HA or CS in the 12 months before TKA. For patients who used HA and/or CS within 3 months prior to TKA, the unadjusted incidence of PJI at 2-year post-TKA was 0.75% for the CS group, 1.07% for the HA group, and 1.00% for both CS and HA group, compared with 0.77% for those who did not use HA or CS. The number of injections performed per year was inconsistently associated with PJI risk. Overall, we found that intra-articular injections given within the 4-month period prior to TKA were not associated with elevated PJI risk (evaluated at 1, 3, 12, and 24 months after the index TKA) within the elderly Medicare patient population.

Effect of Manual versus Robotic-Assisted Total Knee Arthroplasty on Cervical Spine Static and Dynamic Postures.

This study compared surgeon cervical (C) spine postures and repetitive motions when performing traditional manual total knee arthroplasty (MTKA) versus robotic-assisted TKA (RATKA). Surgeons wore motion trackers on T3 vertebra and the occiput anatomical landmarks to obtain postural and repetitive motion data during MTKA and RATKA performed on cadavers. We assessed (1) flexion-extension at T3 and the occiput anatomical landmarks, (2) range of motion (ROM) as the percentage of time in the flexion-extension angle, (3) repetition rate, defined as the number of the times T3 and the occiput flexion-extension angle exceeded ±10°; and (4) static posture, where T3 or occiput postures exceed 10° for more than 30 seconds. The average T3 flexion-extension angle for MTKA cases was 5-degree larger than for RATKA cases (19 ± 8 vs. 14 ± 8 degrees). The surgeons who performed MTKA cases spent 15% more time in nonneutral C-spine ROM than those who performed RATKA cases (78 ± 25 vs. 63 ± 36%, p < 0.01). The repetition rate at T3 was 4% greater for MTKA than RATKA (14 ± 5 vs. 10 ± 6 reps/min). The percentage of time spent in static T3 posture was 5% greater for overall MTKA cases than for RATKA cases (15 ± 3 vs. 10 ± 3%). In this cadaveric study, we found differences in cervical and thoracic ergonomics between manual and robotic-assisted TKA. Specifically, we found that RATKA may reduce a surgeon's ergonomic strain at both the T3 and occiput locations by reducing the time the surgeon spends in a nonneutral position.

A Survey of the Impact of the COVID-19 Crisis on Skill Decay Among Surgery and Anesthesia Residents.

OBJECTIVE: The SARS-CoV-2 (COVID-19) pandemic has profoundly impacted healthcare delivery and strained medical training. This study explores resident and faculty perceptions regarding the impact of the COVID-19 crisis on technical skill decay of surgical and anesthesia residents. We hypothesized that many residents perceived that their technical abilities diminished due to a short period of interruption in their training. DESIGN: An IRB-exempt, web-based cross-sectional survey distributed to residents and faculty SETTING: Two large academic tertiary medical centers, North Shore University Hospital and Long Island Jewish Medical Center, of the Northwell Health System in New York. PARTICIPANTS: General surgery, anesthesiology, plastic surgery, cardiothoracic surgery, orthopedic surgery, oral maxillofacial surgery, urology, podiatry residents and faculty. RESULTS: All residents reported a significant impact on their training. Residents (82%) and faculty (94%) reported a significant reduction in case volumes due to the COVID-19 pandemic (p < 0.05). 64% of residents reported a reduction in technical skills, and 75% of faculty perceived a decrease in resident technical skills. Residents were concerned about fulfilling ACGME case requirements, however faculty were more optimistic that residents would achieve level-appropriate proficiency by the conclusion of their training. Both residents and faculty felt that resident critical care skills improved as a result of redeployment to COVID-19 intensive care units (66% and 94%). Additionally, residents reported increased confidence in their ability to care for critically ill patients and positive impact on professional competencies. CONCLUSIONS: Effects of the COVID-19 pandemic on residency training are multi-dimensional. The majority of surgical and anesthesia residents perceived that their technical ability diminished as a result of skill decay, whereas other skillsets improved. Longitudinal surveillance of trainees is warranted to evaluate the effect of reduced operative volume and redeployment on professional competency.

Does Time Spent in the Post-Anesthesia Care Unit Affect Hospital Lengths of Stay following Primary Total Knee Arthroplasty?

Given the current healthcare economic environment, substantial efforts have been made to help streamline the in-hospital care for total knee arthroplasty (TKA) patients. While potential cost-reducing factors have been identified in the literature, analyses specifically considering post-anesthesia care unit (PACU) lengths of stay (LOS) are lacking. Therefore, the purpose of this study was to identify factors associated with (1) longer PACU LOS as well as (2) longer Hospital LOS. Prospectively collected TKA data from seven participating hospitals within a large health system were evaluated for patient demographics, body mass indices, Charlson Comorbidity Indices (CCI), surgeon volumes/training, admission types, anesthesia types, PACU LOS, and overall hospital LOS. Complete data was available for 1,690 patients (1,082 females, mean age: 67 years). Univariate and multivariate analytical models were constructed to identify which factors were predictive of longer PACU and overall hospital LOS. Same-day admissions, higher volume surgeons (≥ 100 cases per year), fellowship-trained arthroplasty surgeons, and longer operative times were associated with longer PACU LOS (p < 0.05). Multivariate analyses found age more than or equal to 65 years (ß= 0.124) and CCI more than or equal to 3 (ß= 0.088) to be associated with longer hospital LOS (p < 0.001). Operative times, PACU LOS, and procedure times (operative time plus PACU LOS) were not associated with longer hospital LOS (p > 0.05). These data identify associative factors for PACU LOS, as well as the influence of time spent in the PACU on overall hospital LOS. Interestingly, this analysis revealed that patients of arthroplasty fellowship-trained and higher-volume surgeons had longer PACU LOS; however, this could be explained by the observation that these particular surgeons tend to perform more complex deformity cases. Also of importance, increased PACU LOS, meaning the patient spent more time in a high-monitored setting immediately after surgery, did not necessarily confer a longer overall hospital LOS. Based on these data, it may be more beneficial to identify alternate sources than time spent in the operating room or PACU to potentially help reduce overall hospital LOS. LEVEL OF EVIDENCE: II, prospective cohort.

Comparison of Iatrogenic Soft Tissue Trauma in Robotic-Assisted versus Manual Partial Knee Arthroplasty.

Partial knee arthroplasty (PKA) is performed to treat end-stage osteoarthritis in a single compartment. There are minimal data characterizing soft-tissue injuries for PKA with robotic and manual techniques. This cadaver study compared the extent of soft-tissue trauma sustained through robotic-arm assisted PKA (RPKA) and manual PKA (MPKA). Five surgeons prepared 24 cadaveric knees for medial PKA, including six MPKA controls and 18 RPKA assigned into three different workflows: RPKA-LB (six knees) - RPKA with legacy burr; RPKA-NB (six knees) - RPKA with new burr design; and RPKA-NBS (six knees) - RPKA with new burr design and oscillating saw. Two surgeons estimated trauma to the patellar tendon, quadriceps tendon, anterior cruciate ligament (ACL), medial collateral ligament (MCL), medial capsule, posterior capsule, and posterior cruciate ligament (PCLs) using a five-grade system: Grade 1 - complete soft tissue preservation; Grade 2 - ≤25%; Grade 3 - 26 to 50%; Grade 4 - 51 to 75%; and Grade 5 - ≥76% trauma. A total trauma grade was assigned by summing the grades. Kruskal-Wallis statistical tests were used to assess outcomes. When compared to the MPKA group, all RPKA subgroups had lower total trauma grading (p<0.01), lower posterior capsular damage (p<0.01), and less severe ACL damage (p<0.01). The analysis demonstrated no significant difference between the three RPKA workflows. As this study was performed using cadaveric specimens, additional investigations are necessary to determine associations between robotic or manual-assisted technique, observed soft tissue damage, and postoperative clinical outcomes following PKA.