Evaluating the optimal management strategy for intraoperative iatrogenic injury to the medial collateral ligament during primary total knee arthroplasty: A systematic review.

INTRODUCTION: Intraoperative iatrogenic MCL injuries during primary TKA are rare complications that lack a gold standard management protocol. This review aims to provide insight into various treatment modalities and evidence-based guidance for improved patient outcomes. METHODS: A comprehensive search across five databases identified relevant randomized control trials and retrospective cohort studies with reported outcomes. A total of 17 studies were included, and variables such as patient demographics, injury type, management, and Knee Society Scores (KSS) were assessed. The quality of included studies was evaluated using the Critical Appraisal Skills Programme tool. RESULTS: Mean age of included patients ranged from 60.0 to 71.4 years. The mean Body Mass Index ranged from 26.75 to 34.40 kg/m2. Among the included knees, 298 were categorized as MCL avulsion, and 167 as midsubstance/transection injuries. Primary repair with sutures or bone staples emerged as the most common management. Intraoperative MCL injury was correlated with reduced preoperative range of motion (ROM) and postoperative KSS clinical, functional, and pain scores compared to control groups. Postoperative ROM was comparable between MCL injury and control groups, ranging from 100.0° to 130.0° and 107.0° to 130.0°, respectively. CONCLUSION: Current evidence supports primary repair as the preferred management for this complication. Factors such as extent of the tear, type of injury, and the surgeon's experience also help to guide treatment. While treatment modalities like allograft or autograft reconstruction show promise, further research with larger sample sizes is needed to enhance future outcomes.

Antibiotic cement nails manufactured with threaded rods or cannulated intramedullary nails are better than those made with guidewires and do not debond.

Purpose: The purpose of this study was to comparatively evaluate cement debonding at the time of removal of antibiotic cemented coated nails (ABNs) with cores made with a guidewire ($120), a regular intramedullary nail ($1100) or a threaded rod from a circular frame external fixator set ($60). Methods: A retrospective study was performed on 32 ABNs that had been implanted for long bone infections after intramedullary nailing. All ABNs were manufactured intraoperatively by the treating surgeon using 2 grams of vancomycin and single package of Tobramycin Simplex Cement (Stryker, Kalamazoo, MI). The powder, antibiotics, and polymer were mixed and then injected into an ABN cement mold (Bonesetter Holdings USA). Debonding was assessed at time of removal by the operating surgeon. Rates of cement debonding between the 3 groups were statistically compared. Results: Debonding occurred in 0/12 of the cement nails manufactured with an intramedullary nail, 0/7 threaded rod ABNs, and 6/13 guidewire ABNs. There was a significant difference in the rate of debonding between the 3 groups (P < 0.01). Removal of the remnant cement was accomplished with thin osteotomes, long pituitary rongeurs, or reamers. The canal was visualized using an arthroscope to ensure complete removal of the cement. Conclusion: ABNs fabricated with standard intramedullary nails or threaded rods did not lead to any debonding. Debonding of the cement from the inner core of an antibiotic nail often requires significant effort to remove the remnant cement. Given that threaded rods are often cheaper than guidewires, we recommend that ABNs be fabricated with either threaded rods or interlocking nails, but not guidewires, depending on the level of stability required.

A Novel Digital Templating Method for Total Hip Arthroplasty in Patients With Unilateral Hip Arthrosis.

BACKGROUND: Identification of the hip center of rotation (HCOR) before total hip arthroplasty (THA) is crucial for achieving optimal implant position and size, and for restoring native biomechanics around the hip joint. Current techniques for determining the HCOR in cases of abnormal hip anatomy are limited and unreliable. This study presents a novel technique using open-access software for preoperative THA templating for patients with significantly abnormal hip anatomy due to unilateral hip arthrosis. The aim is to reliably predict the HCOR and acetabular implant size compared with a traditional intraoperative method. MATERIALS AND METHODS: This retrospective study involved 20 patients with unilateral hip arthrosis who underwent THA. Preoperative templating was performed using the experimental technique, and the position of the HCOR was measured on preoperative and postoperative radiographs. The positions of the predicted and actual HCOR were compared, along with the inclination and size of the acetabular component. RESULTS: The difference between the predicted and actual HCOR positions was insignificant (0.43±0.22 mm vertically and 0.18±0.20 mm horizontally), and there was a positive correlation between them (r=0.78, P<.005; r=0.72, P<.005). The agreement between the predicted and actual acetabular implant sizes was 85%, with near-perfect interobserver agreement (Cohen's kappa=0.827). CONCLUSION: This novel technique provides a reliable method for predicting HCOR and acetabular implant size for THA in cases of unilateral hip arthrosis. This technique may help optimize biomechanics and improve outcomes in challenging cases. Further research and validation are warranted to establish its broader applicability. [Orthopedics. 2024;47(3):e139-e145.].

Anterior Knee Pain After Total Knee Arthroplasty: A Critical Review of Peripatellar Variables.

¼ Despite the widespread success of total knee arthroplasty (TKA), postoperative anterior knee pain (AKP) remains a common occurrence and source of dissatisfaction with several readily discernible and diagnosable causes of AKP after TKA, including component malpositioning, infection, wear and osteolysis, instability, and loosening, among others.¼ In the setting of the well-appearing but painful TKA, potential intraoperative contributors to AKP have been extensively investigated, but remain controversial and include patellar resurfacing, patellar denervation, and patellofemoral joint overstuffing or understuffing.¼ Intraoperative management of peripatellar soft tissues has comparatively attained substantially less attention recently, and persistent controversy exists in the literature to make informed decisions on soft-tissue management and identify potential contributors to AKP.¼ Further investigations and research is needed, including exploration of multifactorial or alternative etiologies, specifically ones related to less obvious soft-tissue-related factors, needed to better understand and ultimately avoid AKP after TKA.

Improved performance of machine learning models in predicting length of stay, discharge disposition, and inpatient mortality after total knee arthroplasty using patient-specific variables.

BACKGROUND: This study aimed to compare the performance of ten predictive models using different machine learning (ML) algorithms and compare the performance of models developed using patient-specific vs. situational variables in predicting select outcomes after primary TKA. METHODS: Data from 2016 to 2017 from the National Inpatient Sample were used to identify 305,577 discharges undergoing primary TKA, which were included in the training, testing, and validation of 10 ML models. 15 predictive variables consisting of 8 patient-specific and 7 situational variables were utilized to predict length of stay (LOS), discharge disposition, and mortality. Using the best performing algorithms, models trained using either 8 patient-specific and 7 situational variables were then developed and compared. RESULTS: For models developed using all 15 variables, Linear Support Vector Machine (LSVM) was the most responsive model for predicting LOS. LSVM and XGT Boost Tree were equivalently most responsive for predicting discharge disposition. LSVM and XGT Boost Linear were equivalently most responsive for predicting mortality. Decision List, CHAID, and LSVM were the most reliable models for predicting LOS and discharge disposition, while XGT Boost Tree, Decision List, LSVM, and CHAID were most reliable for mortality. Models developed using the 8 patient-specific variables outperformed those developed using the 7 situational variables, with few exceptions. CONCLUSION: This study revealed that performance of different models varied, ranging from poor to excellent, and demonstrated that models developed using patient-specific variables were typically better predictive of quality metrics after TKA than those developed employing situational variables. LEVEL OF EVIDENCE: III.

Assessing the predictive capacity of machine learning models using patient-specific variables in determining in-hospital outcomes after THA.

Background: Machine learning is a subset of artificial intelligence using algorithmic modeling to progressively learn and create predictive models. Clinical application of machine learning can aid physicians through identification of risk factors and implications of predicted patient outcomes. Aims: The aim of this study was to compare patient-specific and situation perioperative variables through optimized machine learning models to predict postoperative outcomes. Methods: Data from 2016 to 2017 from the National Inpatient Sample was used to identify 177,442 discharges undergoing primary total hip arthroplasty, which were included in the training, testing, and validation of 10 machine learning models. 15 predictive variables consisting of 8 patient-specific and 7 situational specific variables were utilized to predict 3 outcome variables: length of stay, discharge, and mortality. The machine learning models were assessed in responsiveness via area under the curve and reliability. Results: For all outcomes, Linear Support Vector Machine had the highest responsiveness among all models when using all variables. When utilizing patient-specific variables only, responsiveness of the top 3 models ranged between 0.639 and 0.717 for length of stay, 0.703-0.786 for discharge disposition, and 0.887-0.952 for mortality. The top 3 models utilizing situational variables only produced responsiveness of 0.552-0.589 for length of stay, 0.543-0.574 for discharge disposition, and 0.469-0.536 for mortality. Conclusions: Linear Support Vector Machine was the most responsive machine learning model of the 10 algorithms trained, while decision list was most reliable. Responsiveness was observed to be consistently higher with patient-specific variables than situational variables, emphasizing the predictive capacity and value of patient-specific variables. The current practice in machine learning literature generally deploys a single model, it is suboptimal to develop optimized models for application into clinical practice. The limitation of other algorithms may prohibit potential more reliable and responsive models.Level of Evidence III.

Epidemiology of primary and revision total knee arthroplasty: analysis of demographics, comorbidities and outcomes from the national inpatient sample.

INTRODUCTION: Primary total knee arthroplasty (TKA) is a preferred treatment for end-stage knee osteoarthritis. In the setting of a failed TKA, revision total knee arthroplasty (rTKA) acts as a salvage procedure and carries a higher risk compared to primary TKA. Given increased interest in postoperative outcomes from these procedures, a thorough understanding of the demographics, comorbidities, and inpatient outcomes is warranted. This study aimed to report the epidemiological data of demographics, comorbidity profiles and outcomes of patients undergoing TKA and rTKA. METHODS: A retrospective review of NIS registry discharge data from 2006 to 2015 third quarter was performed. This study included adults aged 40 and older who underwent TKA or rTKA. A total of 5,901,057 TKA patients and 465,968 rTKA patients were included in this study. Simple descriptive statistics were used to present variables on demographics, medical comorbidities, and postoperative complications. RESULTS: A total of 5,901,057 TKA and 465,968 rTKA discharges were included in this study, with an average age of 66.30 and 66.56 years, and the major payor being Medicare, accounting for 55.34% and 59.88% of TKA and rTKA cases, respectively. Infection (24.62%) was the most frequent reason for rTKA, and was followed by mechanical complications (18.62%) and dislocation (7.67%). The most common medical comorbidities for both groups were hypertension, obesity, and diabetes. All types of inpatient complications were reported in 22.21% TKA and 28.78% of rTKA cases. Postoperative anemia was the most common complication in both groups (20.34% vs. 25.05%). CONCLUSIONS: Our data demonstrated a 41.9% increase in patients receiving TKA and 28.8% increase in rTKA from the years 2006 to 2014. The data showed a 22.21% and a 28.78% "complication" rate with TKA and rTKA, with postoperative anemia being the most common complication. The top 3 medical comorbidities were hypertension, obesity, and diabetes for both groups and with increased focus on perioperative optimization, future analyses into preoperative medical optimization, and improved primary arthroplasty protocol may result in improved postoperative outcomes.

Comorbidity, Racial, and Socioeconomic Disparities in Total Knee and Hip Arthroplasty at High Versus Low-Volume Centers.

INTRODUCTION: The purpose of this study was to compare the epidemiologic and demographic profiles and inpatient postoperative complication and economic outcomes of patients undergoing total joint arthroplasty of the hip and knee (TJA) at high-volume centers (HVCs) versus low-volume centers (LVCs) using a large national registry. METHODS: This retrospective cohort study used data from the National Inpatient Sample from 2006 to the third quarter of 2015. Discharges representing patients aged 40 years or older receiving a primary total hip arthroplasty or total knee arthroplasty were included. Patients were stratified into those undergoing their procedure at HVCs versus LVCs. Epidemiologic, demographic, and inpatient postoperative complications and economic outcomes were comparatively analyzed between groups. RESULTS: A total of 7,694,331 TJAs were conducted at HVCs while 1,044,358 were conducted at LVCs. Patients at LVCs were more likely to be female, be Hispanic, be non-Hispanic Black, and use Medicare and Medicaid than patients at HVCs. Of the 29 Elixhauser comorbidities examined, 14 were markedly higher at LVCs while 11 were markedly higher at HVCs. Patients who underwent TJA at LVCs were more likely to develop cardiac, respiratory, gastrointestinal, genitourinary, hematoma/seroma, wound dehiscence, and postoperative infection complications and were more likely to die during hospitalization. Patients at HVCs were more likely to develop postoperative anemia. Length of stay and total charges were higher at LVCs compared with HVCs. DISCUSSION: There are notable differences in the demographics, epidemiologic characteristics, and inpatient outcomes of patients undergoing TJA at HVCs versus LVCs. Attention should be directed to identifying and applying the specific resources, processes, and practices that improve outcomes at HVCs while referral practices and centralization efforts should be mindful to not worsen already existing disparities.

Frailty Among Total Hip and Knee Arthroplasty Recipients: Epidemiology and Propensity Score-weighted Analysis of Effect on In-hospital Postoperative Outcomes.

INTRODUCTION: Total joint arthroplasty (TJA) is one of the most successful and frequently performed procedures in the United States. The number of these procedures is projected to continue growing rapidly in the coming years, and with it comes the demand for more sophisticated perioperative risk and complication assessment. This study examines the effect of frailty on postoperative inpatient complications and hospital resource utilization after TJA. METHODS: Discharge data from the National Inpatient Sample were used to identify all patients aged 50 years or older who underwent TJA between 2006 and 2015. Nonelective admissions and hip fractures were excluded. Patients were stratified into two groups with and without concomitant ICD-9 diagnostic criteria that qualified them has having frailty. An analysis comparing the 2 groups' epidemiology, medical comorbidities, and propensity score-weighted postoperative clinical and economic outcomes was done. RESULTS: A total of 7,854,890 TJAs were included in this analysis, with 136,516 meeting the criteria for frailty and 7,718,374 being nonfrail. Among these patients, the average age was 67.3 years and the female distribution was 61.1%. Frail patients were found to have markedly higher rates of all but two individual comorbidities constituting the Modified Elixhauser Profile compared with nonfrail patients. Compared with the control group, frail patients were found to have increased risk of any postoperative complication, central nervous system complications, hematoma/seroma, wound dehiscence, infection, and postoperative anemia. Frail patients also had longer length of stay, higher discharge to rehabilitation facilities, and higher hospital charges. DISCUSSION: Patients with frailty undergoing TJA procedures are at a markedly higher risk for developing postoperative complications and worse hospital economic outcomes. As this patient population continues to increase, it is imperative for clinicians to use their risk factors in optimizing their perioperative care and support.

Epidemiology of total hip arthroplasty: demographics, comorbidities and outcomes.

BACKGROUND: Primary THA (THA) is a successful procedure for end-stage hip osteoarthritis. In the setting of a failed THA, revision total hip arthroplasty (rTHA) acts as a salvage procedure. This procedure has increased risks, including sepsis, infection, prolonged surgery time, blood loss, and increased length of stay. Increasing focus on understanding of demographics, comorbidities, and inpatient outcomes can lead to better perioperative optimization and post-operative outcomes. This epidemiological registry study aimed to compare the demographics, comorbidity profiles, and outcomes of patients undergoing THA and rTHA. METHODS: A retrospective review of discharge data reported from 2006 to the third quarter of 2015 using the National Inpatient Sample registry was performed. The study included adult patients aged 40 and older who underwent either THA or rTHA. A total of 2,838,742 THA patients and 400,974 rTHA patients were identified. RESULTS: The primary reimbursement for both THA and rTHA was dispensed by Medicare at 53.51% and 65.36% of cases respectively. Complications arose in 27.32% of THA and 39.46% of rTHA cases. Postoperative anemia was the most common complication in groups (25.20% and 35.69%). Common comorbidities in both groups were hypertension and chronic pulmonary disease. rTHA indications included dislocation/instability (21.85%) followed by mechanical loosening (19.74%), other mechanical complications (17.38%), and infection (15.10%). CONCLUSION: Our data demonstrated a 69.50% increase in patients receiving THA and a 28.50% increase in rTHA from the years 2006 to 2014. The data demonstrated 27.32% and 39.46% complication rate with THA and rTHA, with postoperative anemia as the most common cause. Common comorbidities were hypertension and chronic pulmonary disease. Future analyses into preoperative optimizations, such as prior consultation with medical specialists or improved primary hip protocol, should be considered to prevent/reduce postoperative complications amongst a progressive expansion in patients receiving both THA and rTHA.

Antibiotic Cement-Coated Interlocked Intramedullary Nails for the Treatment of Infected Nonunion After Intramedullary Nailing.

OBJECTIVE: To evaluate outcomes using an interlocking antibiotic cement-coated nail and culture-specific systematic antibiotics in the treatment of infected nonunion after intramedullary nailing. DESIGN: Retrospective observational cohort study. SETTING: Urban level I trauma center. PATIENTS/PARTICIPANTS: Forty-one nonconsecutive patients who presented to a level I trauma center who underwent interlocked antibiotic nailing for treatment of infected nonunion status after primary intramedullary nailing. OUTCOMES: Eradication of infection, radiographic union by 2-year follow-up. RESULTS: Antibiotic nailing successfully eradicated infection and led to fracture healing in 35 patients (85.4%), while 6 patients (14.6%) had persistent infection and required further surgical treatment. Of the 6 patients who required further treatment, 5 eventually went on to heal with fracture union and eradication of their infection, while 1 required a salvage procedure. Of the 5 patients who eventually went on to heal, 4 of them healed with repeat antibiotic or intramedullary nails, while 1 required segmental resection and bone grafting before healing. CONCLUSIONS: This study suggests that the proposed interlocked antibiotic nailing technique is a viable therapeutic option to eradicate infected nonunion and support fracture healing. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Underweight Body Mass Index Is Associated With Increased In-Hospital Complications and Length of Stay After Revision Total Joint Arthroplasty.

INTRODUCTION: The purpose of this study was to assess the impact of underweight status on in-hospital postoperative outcomes and complications after revision total joint arthroplasty (rTJA) of the hip and knee. METHODS: Data from the National Inpatient Sample were used to identify all patients undergoing rTJA in the United States between 2006 and 2015. Patients were divided into two groups based on a concomitant diagnosis of underweight body mass index and a control normal weight group. Propensity score analysis was performed to determine whether underweight body mass index was a risk factor for in-hospital postoperative complications and resource utilization. RESULTS: A total of 865,993 rTJAs were analyzed. Within the study cohort, 2,272 patients were classified as underweight, whereas 863,721 were classified as a normal weight control group. Underweight patients had significantly higher rates of several comorbidities compared with the control cohort. Underweight patients had significantly higher rates of any complication (49.98% versus 33.68%, P = 0.0004) than normal weight patients. Underweight patients also had significantly greater length of stay compared with normal weight patients (6.50 versus 4.87 days, P < 0.0001). CONCLUSION: Underweight patients have notably higher rates of any complication and longer length of stay after rTJA than those who are not underweight. These results have important implications in preoperative patient discussions and perioperative management. Standardized preoperative protocols should be developed and instituted to improve outcomes in this patient cohort.

Femoral Stem Cementation in Primary Total Hip Arthroplasty.

➢: Femoral stem cementation has undergone considerable investigation since bone cement was first used in arthroplasty, leading to the evolution of modern femoral stem cementation techniques. ➢: Although there is a worldwide trend toward the use of cementless components, cemented femoral stems have shown superiority in some studies and have clear indications in specific populations. ➢: There is a large evidence base regarding cement properties, preparation, and application techniques that underlie current beliefs and practice, but considerable controversy still exists. ➢: Although the cementing process adds technical complexity to total hip arthroplasty, growing evidence supports its use in certain cohorts. As such, it is critical that orthopaedic surgeons and investigators have a thorough understanding of the fundamentals and evidence underlying modern cementation techniques.

Comparative Analysis of the Ability of Machine Learning Models in Predicting In-hospital Postoperative Outcomes After Total Hip Arthroplasty.

BACKGROUND: Machine learning (ML) methods have shown promise in a wide range of applications including the development of patient-specific predictive models before surgical interventions. The purpose of this study was to develop, test, and compare four distinct ML models to predict postoperative parameters after primary total hip arthroplasty. METHODS: Data from the Nationwide Inpatient Sample were used to identify patients undergoing total hip arthroplasty from 2016 to 2017. Linear support vector machine (LSVM), random forest (RF), neural network (NN), and extreme gradient boost trees (XGBoost) predictive of mortality, length of stay, and discharge disposition were developed and validated using 15 predictive patient-specific and hospital-specific factors. Area under the curve of the receiver operating characteristic (AUCROC) curve and accuracy were used as validity metrics, and the strongest predictive variables under each model were assessed. RESULTS: A total of 177,442 patients were included in this analysis. For mortality, the XGBoost, NN, and LSVM models all had excellent responsiveness during validation while RF had fair responsiveness. LSVM had the highest responsiveness with an AUCROC of 0.973 during validation. For the length of stay, the LSVM and NN models had fair responsiveness while the XGBoost and random forest models had poor responsiveness. LSVM had the highest responsiveness with an AUCROC of 0.744 during validation. For the discharge disposition outcome, LSVM had good responsiveness while the XGBoost, NN, and RF models all had fair responsiveness. LSVM had the highest responsiveness with an AUCROC of 0.801. DISCUSSION: The ML methods tested demonstrated a range of poor-to-excellent responsiveness and accuracy in the prediction of the assessed metrics, with LSVM being the best performer. Such models should be further developed, with eventual integration into clinical practice to inform patient discussions and management decision making, with the potential for integration into tiered bundled payment models.

Single incision fasciotomy for acute compartment syndrome of the leg: A systematic review of the literature.

Purpose: To review published literature assessing clinical outcomes and complication rates of single incision fasciotomy in fractures of the lower leg. Methods: We searched PubMed and EMBASE for articles published through July 5, 2021, using the terms "single incision fasciotomy", "acute compartment syndrome of the limbs", "compartment syndrome fasciotomy", and "(compartment syndrome fasciotomy) AND (incision)". The inclusion criteria were studies of Level I to IV evidence in English, published in 1970 or later, involving human subjects, reporting clinical outcomes of single incision fasciotomy performed in cases of acute compartment syndrome in lower leg fractures, including at least 1 patient. Results: Among the 3040 combined total results, 11 primary studies met our inclusion criteria. Adequate and safe compartment release was achieved with single-incision technique. No significant difference was found in terms of complications such as infection and non-union. Conclusions: The comparative efficacy and safety of single-incision fasciotomy is relatively equal to the two-incision techniques when evaluated in the literature. However, double-incision fasciotomy remains the predominant surgical technique, widely preferred by surgeons due to the familiarity with the technique and ease of full compartment release. In addition to the actual fasciotomy procedure, data suggests that operative timing, closure and fixation techniques can significantly impact patient outcomes. These findings may be used to guide the orthopedic community when determining the optimal incision-type to use in acute compartment syndrome emergencies for lower-extremity fracture cases in conjunction with closure and fixation techniques.

Predictive capacity of four machine learning models for in-hospital postoperative outcomes following total knee arthroplasty.

Background: Machine learning (ML) methods have shown promise in the development of patient-specific predictive models prior to surgical interventions. The purpose of this study was to develop, test, and compare four distinct ML models to predict postoperative parameters following primary total knee arthroplasty (TKA). Methods: Data from the Nationwide Inpatient Sample was used to identify patients undergoing TKA during 2016-2017. Four distinct ML models predictive of mortality, length of stay (LOS), and discharge disposition were developed and validated using 15 predictive patient and hospital-specific factors. Area under the curve of the receiver operating characteristic curve (AUCROC) and accuracy were used as validity metrics, and the strongest predictive variables under each model were assessed. Results: A total of 305,577 patients were included. For mortality, the XGBoost, neural network (NN), and LSVM models all had excellent responsiveness during validation, while random forest (RF) had fair responsiveness. For predicting LOS, all four models had poor responsiveness. For the discharge disposition outcome, the LSVM, NN, and XGBoost models had good responsiveness, while the RF model had poor responsiveness. LSVM and XGBoost had the highest responsiveness for predicting discharge disposition with an AUCROC of 0.747. Discussion: The ML models tested demonstrated a range of poor to excellent responsiveness and accuracy in the prediction of the assessed metrics, with considerable variability noted in the predictive precision between the models. The continued development of ML models should be encouraged, with eventual integration into clinical practice in order to inform patient discussions, management decision making, and health policy.

The Impact of COVID-19 on the Orthopaedic Surgery Residency Experience.

INTRODUCTION: The rapid spread of the COVID-19 virus led to dramatic changes in graduate medical education and surgical practice. The purpose of this study was to evaluate the effects of the COVID-19 pandemic on Orthopaedic Surgery residency education in the United States. METHODS: A survey sent to all residents of the 201 ACGME-accredited Orthopaedic Surgery programs in the United States. RESULTS: A total of 309 Orthopaedic surgery residents responded to our survey. A subset of 283 (91.6%) residents surveyed reported decreased Orthopaedic-related clinical duty hours due to the COVID-19 pandemic, and 300/309 (97.1%) reported a decrease in surgical case volume. 298 (96.4%) residents reported that their program had scheduled activities or made changes to supplement their education, most common being virtual and video conferences 296/309 (95.5%), required practice questions 132/309 (42.7%), required reading or pre-recorded lectures 122/309 (39.5%), in-person small group meetings or lectures 24/309 (7.77%), and surgical simulation activities 17/309 (5.50%). Almost half (152/309 (48.9%)) of respondents reported their overall resident education was somewhat or much worse due to the impact of COVID-19. Over a quarter (81 (26.2%)) of residents reported their well-being was negatively impacted by residency-related changes due to COVID-19. CONCLUSIONS: Based on these results, the COVID-19 pandemic has brought about significant changes to the training experience of Orthopaedic surgery residents in the United States. Although the majority of residents in this sample had favorable opinions of the educational changes their programs have instituted in light of the pandemic, clinical duty hours and case volume were reported to have substantially decreased, with a large portion of residents viewing their overall resident education as worsened and reporting negative impacts on their overall well-being.

The prevalence of posterolateral tibial baseplate overhang: An anatomical CT study.

INTRODUCTION: Total Knee Arthroplasty (TKA) is used in patients with osteoarthritis who have failed conservative management to reduce pain, improve functional outcomes and ultimately quality of life. However, less than optimal patient satisfaction has led to continued improvements in design and technology of TKA. One factor that can limit patient satisfaction is postero-lateral overhang of the tibial baseplate. The purpose of our study is to utilize pre-operative CT scans to assess the prevalence of posterolateral tibial overhang with the use of a symmetric tibial baseplate component in a popular knee system with robotic assistance. METHODS: Ninety-eight (98) consecutive patients who underwent robotic-assisted total knee arthroplasty (TKA) were included in this study. Using both the most medial aspect of the tibial tubercle and the medial ⅓ of the tibial tubercle as reference points, we quantified the extent of posterolateral overhang when determining the rotation of the tibial component. RESULTS: Using the most medial aspect of the tibial tubercle as a reference point for rotation of the tibial baseplate, 63% of the instances of reviewed CT scans (369/588) had posterolateral overhang. Furthermore, 81% (406/588) had posterolateral overhang when using the medial ⅓ aspect of the tibial tubercle as the reference for rotation of the tibial baseplate. The average posterolateral tibial baseplate overhang was 1.5 mm (range 0-8 mm) when using the most medial aspect of the tibial tubercle and 2.4 mm (range 0-8 mm) when using the medial ⅓ tibial tubercle as the centering point for the tibial baseplate. DISCUSSION: Tibial baseplate overhang could lead to potential pain from irritation of soft tissues. To our knowledge, this is the first study that was able to valencquantify the amount of tibial baseplate overhang using pre-operative CT scans. Rotational alignment of the tibial baseplate needs to be balanced to ensure minimal lateral overhang while achieving sufficient external rotation of the tibial component. An asymmetric tibial component may provide a compromise in certain situations. LEVEL OF EVIDENCE: Diagnostic level IV case series.