The Development and Application of a Forearm Simulator to Investigate Radial Head Biomechanics

The forearm is a complex articular unit, with poorly understood biomechanics. A novel forearm simulator to facilitate physiologic testing of cadavers for multiple clinical scenarios was designed, manufactured and validated. A number of outcome measurements were potentiated including the forearm’s resistance to rotation, radiocapitellar contact pressure and area as well as IOM loads. Testing of changes to forearm biomechanics due to radial head excision and variations of radial head arthroplasty dimensions was conducted. Radial head arthroplasty using the correct radial head length and diameter recreated the biomechanics of an intact forearm. Radial head excision as well an implant of non-anatomic length or diameter created abnormal radiocapitellar joint properties and load transfer within the forearm. The simulator had good repeatability and reproducibility. If radial head arthroplasty is clinically required, an implant that is similar in dimensions to the native radial head maintains native forearm biomechanics

Contemporary Strategies to Prevent Infection in Hip and Knee Arthroplasty

© 2020, Springer Science+Business Media, LLC, part of Springer Nature. Purpose of Review: Prosthetic joint infection (PJI) remains a serious concern in lower limb arthroplasty. Despite the significant consequences of PJI, the assessment of the safety and efficacy of preventative measures is challenging due to a low event rate. Notwithstanding, enormous efforts have been made in this arena, and prevention strategies continue to evolve. This review provides an update on contemporary literature (published within the last 5 years) pertaining to infection prevention in primary hip and knee arthroplasty. Recent Findings: Patient optimization has been highlighted as a critical preoperative factor in mitigating PJI risk. Recent evidence emphasizes the importance of preoperative glycaemic control, nutritional status, weight optimization and smoking cessation prior to hip and knee arthroplasty. Perioperatively, attention to detail in terms of surgical skin preparation agent and technique as well as prophylactic antibiotic agent, spectrum, dose and timing is important with statistically and clinically significant differences seen between differing strategies. Intraosseous regional antibiotic administration is an emerging technique with promising preclinical data. Dilute betadine lavage also shows promise. Data supporting bundled interventions continues to grow. Summary: A multimodal approach is required in PJI prevention, and attention to detail is important with each element. Patient optimization is critical, as is the execution of the planned perioperative infection prevention strategy

Functional outcomes of acutely infected knee arthroplasty: A comparison of different surgical treatment options

© 2015 8872147 Canada Inc. Background: An infected total knee arthroplasty (TKA) can be treated with irrigation and débridement with polyethylene exchange (IDPE) or a 2-staged revision (2SR). Although research has examined infection eradication rates of both treatments, patient outcomes have not been reported. We examined patient-reported outcomes following treatment compared with matched, noninfected controls. Methods: We retrospectively identified patients with infected TKAs who had undergone the index procedure between May 1991 and November 2011. Patient-reported outcomes included the 12-item Short Form Health Survey, Western Ontario and McMaster Universities Arthritis Index, and Knee Society Scores as well as range of motion. Patients with noninfected primary TKAs matched by age and age-adjusted Charlson Comorbidity Index score were used as controls. Intention-to-treat groups of 2SR and IDPE were used, with the IDPE group subdivided into successful and unsuccessful groups. Results: We included 145 patients with infected TKAs with mean follow-up of 64.2 months and 145 controls with a mean follow-up of 35.4 months in our analysis. Outcomes of the controls and the successful IDPE groups were equivalent. The 2SR cohort had lower scores in all categories than controls. There was a 39% success rate in eradicating infection with IDPE. Patients in whom IDPE failed had lower scores in all categories than controls. There was no difference between the failed IDPE group and the 2SR group. Conclusion: Controversy regarding treatment options for acutely infected TKA has been focused on infection eradication. However, functional outcomes following treatment need to be taken into consideration. Patients whose infections were successfully treated with IDPE had equivalent outcomes to controls

Quantifying physical and psychological outcomes after periprosthetic femoral fracture in older adults

Background: Total hip arthroplasty (THA) and total knee arthroplasty (TKA) are common and effective treatments for osteoarthritis. Falls risk is increased after these surgeries due to age, proprioceptive changes and leg weakness. One devastating consequence of falling after these surgeries, both functionally and psychologically, is a peri-prosthetic femoral fracture (PFF). Existing research on PFF has focused on surgical management and not the functional or psychological impacts to the person after this injury. Hypothesis/Objectives: The study objectives are: 1) To evaluate the subjective and objective functional and psychological outcomes after sustaining a PFF, and 2) to estimate the prevalence of falls since the PFF and future falls risk. Proposed Methods: Participants will be recruited through the Orthopedic Outpatient Clinic at London Health Sciences Center. A self-report questionnaire will measure subjective functional ability (e.g., walking, driving) and psychological (e.g., depression, social isolation) outcomes. Future falls risk will be measured with the Falls Risk in Older People in a Community Setting (FROP-Com) scale and fear of falling by the Activities-specific Balance Confidence (ABC) scale. Participants will perform physical performance tests: 30-Second Sit to Stand Test and Step Test for measuring lower limb strength and balance, respectively. Data will be summarized in means and standard deviations or proportions and percentages as appropriate. Future Implications: There is limited knowledge about the functional and psychological outcomes after PFF post-THA/TKA. Understanding the effects that PFF can have on older adults is critical to health providers and patients in order to set appropriate rehabilitation goals to improve quality of life

Understanding the patellofemoral joint in total knee arthroplasty

© 2019 Joule Inc. or its licensors. Total knee arthroplasty (TKA) is one of the most successful procedures in orthopedic surgery. Nevertheless, postoperative patellofemoral complications remain a challenging problem, affecting a substantial proportion of patients. Complications involving the patellofemoral joint (PFJ) can occur in both resurfaced and nonresurfaced patellae. Types of PFJ complications include anterior knee pain, maltracking, fracture, avascular necrosis and patellar clunk. The causes of patellofemoral complications can be categorized into patient-, surgeon- and implant-related factors. Patient characteristics such as female sex, young age, depression and increased body mass index have been linked with increased complications. Important technical considerations to avoid complications include achieving appropriate rotational alignment of the femoral and tibial components, maintaining joint line height, medializing the patellar button and avoiding overstuffing the PFJ. Component design features such as conformity, shape and depth of the femoral trochlea have also been shown to be important. Although the cause of patellofemoral complications after TKA may sometimes be unknown, it remains important to minimize errors that can lead to these complications

Significant cost savings and similar patient outcomes associated with early discharge following total knee arthroplasty

© 2019 Joule Inc. or its licensors. Background: A substantial portion of the cost of total knee arthroplasty (TKA) results from the postoperative inpatient length of stay (LOS). Considering the annual increase in TKAs, reducing LOS represents a potential for cost savings. We sought to compare in-hospital costs and patient-reported outcomes for an early discharge protocol compared with the standard LOS following TKA. Methods: We conducted a retrospective matched cohort study, matching patients on age, sex, body mass index and preoperative Western Ontario & McMaster Universities Osteoarthritis Index (WOMAC) score. We compared costs associated with time in the operating room, intraoperative pain control and inpatient stay as well as 1-year postoperative patient-reported outcomes between early discharge and standard LOS groups. Results: We included 50 patients in our study (25 per group). The average LOS in the early discharge group was 26.5 hours, compared with 48.9 hours in the standard care group. The early discharge group had higher intraoperative costs associated with pain control (mean difference 26.98, 95% confidence interval 14.41-37.90, p \u3c 0.01); however, this difference was offset by substantial savings associated with the reduced LOS. The mean total cost for the early discharge group was $649.62 ±$281.71 versus $1279.71 ±$515.98 for the standard care group. There were no significant differences in SF12 or WOMAC scores between groups at 1 year postoperative. Conclusion: In-hospital costs were significantly lower with a postoperative day 1 discharge protocol than with standard LOS following TKA, with no difference in patient-reported outcomes

Le point de vue des patients sur le degré de participation des résidents en salle d’opération dans le cas d’une arthroplastie totale de la hanche ou du genou

Introduction: Previous work suggests that patients do not understand the extent of trainee involvement in their care and are uncomfortable with trainee involvement. Methods: We recruited 202 English speaking patients with previous or planned total joint arthroplasty of the lower limb for a prospective survey trial. We assessed participant’s knowledge of trainee level of education and confidence of trainee involvement in their surgery as a function of supervision. Results: Participants’ mean level of confidence in the consultant surgeon was 4.30 (SD±1.13) on a 5-point Likert scale. Confidence in residents was significantly less, regardless of resident experience (p < 0.05). 11.1% of participants did not want trainees involved in their treatment.  60.6% would like to know more about the education level of the trainee. Less than half of participants correctly identified the education level of residents and fellows. Conclusion: Patient confidence in trainees performing part or all of their surgery increases with resident experience and supervision. Most patients do not understand the hierarchy in education of medical trainees and would like to know more about the education level of the trainee involved in their care. Further work should explore how we can help patients better understand trainee involvement in their surgical care.Contexte: Des travaux antérieurs suggèrent que les patients ne comprennent pas le degré de participation des stagiaires dans leurs soins et que cette participation les rend mal à l’aise. Méthodes : Nous avons recruté 202 patients anglophones qui ont eu ou qui vont avoir une arthroplastie totale du membre inférieur pour un essai prospectif par sondage. Nous avons évalué les connaissances des participants sur le niveau de formation des résidents et leur confiance dans la participation des stagiaires dans l’intervention en fonction de la supervision dont ils font l’objet. Résultats : Le niveau moyen de confiance des participants dans le chirurgien consultant était de 4,30 (SD±1,13) sur une échelle de Likert à 5 points. Le degré de confiance dans les résidents était bien inférieur, quelle que soit l’expérience du résident (p < 0,05). Parmi les participants, 11,1 % ne voulaient pas que les résidents interviennent dans leur traitement et 60,6 % souhaitaient en savoir plus sur leur niveau de formation. Moins de la moitié des participants ont correctement identifié le niveau de formation des résidents et des fellows. Conclusion : La confiance des patients par rapport au fait que les stagiaires effectuent une partie ou la totalité de l’intervention chirurgicale augmente avec l’expérience et la supervision des résidents. La plupart des patients ne comprennent pas les niveaux de formation des stagiaires en médecine et voudraient en savoir plus sur celui du médecin en formation qui intervient dans leurs soins. Des études plus poussées s’imposent sur la manière d’aider les patients à mieux comprendre la participation des stagiaires dans les soins chirurgicaux

Surgical approach in primary total hip arthroplasty: Anatomy, technique and clinical outcomes

©2015 8872147 Canada Inc. Total hip arthroplasty (THA) has revolutionized the treatment of hip arthritis. A number of surgical approaches to the hip joint exist, each with unique advantages and disadvantages. The most commonly used approaches include the direct anterior, direct lateral and posterior approaches. A number of technical intricacies allow safe and efficient femoral and acetabular reconstruction when using each approach. Hip dislocation, abductor insufficiency, fracture and nerve injury are complications of THA, although their relative risk varies by approach. Numerous clinical trials have sought to elicit differences in patient-reported outcomes, complication rates and return to function among the surgical approaches. This review outlines some of the technical pearls of performing a THA through either a direct anterior, direct lateral or posterior approach. A literature review outlines the impact of surgical approach on clinical outcomes and clinically relevant complication rates

A protocol for a randomized controlled trial investigating the safety and cost-effectiveness of outpatient total hip arthroplasty

© 2020 The Author(s). Background: A significant proportion of the overall cost of total hip arthroplasty (THA) results from the inpatient hospital stay following the procedure. Considering the substantial and increasing number of these procedures performed annually, shifting to an outpatient model of care where the patient is discharged home the same day as their surgery represents a potential for significant cost savings. The potential significant impact of an outpatient care model on constrained healthcare budgets and lack of high-quality evidence regarding its effectiveness warrants a rigorous comparative trial. The purpose of this prospective, randomized controlled trial is to evaluate outpatient care pathways for THA. Specifically, our objectives are to compare the rate of serious adverse events and estimate the cost-effectiveness of outpatient compared to standard inpatient THA. Methods: We will include patients undergoing primary THA whom have an American Society of Anaesthetists status equal to or less than three, live within a 60-min driving distance of the institution and have an adult to accompany them home postoperatively and stay with them overnight. Consenting patients will be randomized to be discharged on the same day as surgery, as outpatients, or as inpatients according to standard of care (minimum of one night in hospital) using a modified Zelen consent model. The primary outcome measure is the incidence of serious adverse events at 30 days postoperative. Participants and their caregivers will complete secondary outcomes measures at each follow-up visit including patient-reported outcome measures and self-reported cost questionnaires. Discussion: This protocol is the first randomized trial to use blinding to evaluate outpatient THA compared to standard overnight stay and first to prospectively perform a full economic evaluation. It is also the first adequately powered trial to prospectively assess the safety of outpatient THA. Successful completion of this study could have the potential to provide clinical evidence for the role of outpatient THA in current practice. Trial registration: This study was retrospectively registered on ClinicalTrials.gov (NCT03026764) on March 9th, 2016