Rethinking the 10% strain rule in fracture healing: A distal femur fracture case series.

Since the 1970s, the 2%-10% rule has been used to describe the range of interfragmentary gap closure strains that are conducive for secondary bone healing. Interpreting the available evidence for the association between strain and bone healing remains challenging because interfragmentary strain is impossible to directly measure in vivo. The question of how much strain occurs within and around the fracture gap is also difficult to resolve using bench tests with osteotomy models because these do not reflect the complexity of injury patterns seen in the clinic. To account for these challenges, we used finite element modeling to assess the three-dimensional interfragmentary strain in a case series of naturally occurring distal femur fractures treated with lateral plating under load conditions representative of the early postoperative period. Preoperative computed tomography scans were used to construct patient-specific finite element models and plate fixation constructs to match the operative management of each patient. The simulations showed that gap strains were within 2%-10% only for the lowest load application level, 20% static body weight (BW). Moderate loading of 60% static BW and above caused gap strains that far exceeded 10%, but in all cases, strains in the periosteal region external to the fracture line remained low. Comparing these findings with postoperative radiographs suggests that in vivo secondary healing of distal femur fractures may be robust to early gap strains much greater than 10% because formation of new bone is initiated outside the gap where strains are lower, followed by later consolidation within the gap.

Liposomal Bupivacaine in Adductor Canal Blocks Before Total Knee Arthroplasty Leads to Improved Postoperative Outcomes: A Randomized Controlled Trial.

BACKGROUND: This study compares the use of liposomal bupivacaine (Exparel) versus ropivacaine in adductor canal blocks (ACB) before total knee arthroplasties (TKAs). METHODS: From the months of April 2020 to September 2021, 147 patients undergoing unilateral primary TKA were asked to participate in this prospective, double-blinded randomized controlled trial. Each patient received an iPACK block utilizing ropivacaine and was additionally randomized to receive an ACB with Exparel or Ropivacaine. For each patient, demographic information, inpatient hospital information, postoperative opioid use, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire scores were collected. RESULTS: Overall, 100 patients were included (50 in each cohort). The Exparel group had a lower hospital length of stay compared to the Control group (36.3 vs 49.7 hours, P < .01). Patients in the Exparel group reported an increased amount of Numerical Rating Scale pain score improvement at all postoperative timepoints. These patients also used a lower amount of inpatient opioids (40.9 vs 47.3 MME/d, P = .04) but a similar amount of outpatient opioids (33.4 vs 32.1 MME/d, P = .351). Finally, the Exparel group had increased improvements in all WOMAC subscores and total scores at most timepoints compared to the Control group (P < .05). CONCLUSION: Exparel peripheral regional nerve blocks lead to decreases in pain levels, shorter hospital lengths of stay, inpatient opioid usage, and improved WOMAC scores. Exparel can be safely used in ACB blocks before TKA to help in controlling postoperative pain and decrease length of stay.

Boundary Conditions Matter-Impact of Test Setup on Inferred Construct Mechanics in Plated Distal Femur Osteotomies.

The mechanics of distal femur fracture fixation has been widely studied in bench tests that employ a variety of approaches for holding and constraining femurs to apply loads. No standard test methods have been adopted for these tests and the impact of test setup on inferred construct mechanics has not been reported. Accordingly, the purpose of this study was to use finite element models to compare the mechanical performance of a supracondylar osteotomy with lateral plating under conditions that replicate several common bench test methods. A literature review was used to define a parameterized virtual model of a plated distal femur osteotomy in axial compression loading with four boundary condition sets ranging from minimally to highly constrained. Axial stiffness, fracture gap closure, and transverse motion at the fracture line were recorded for a range of applied loads and bridge spans. The results showed that construct mechanical performance was highly sensitive to boundary conditions imposed by the mechanical test fixtures. Increasing the degrees of constraint, for example, by potting and rigidly clamping one or more ends of the specimen, caused up to a 25× increase in axial stiffness of the construct. Transverse motion and gap closure at the fracture line, which is an important driver of interfragmentary strain, was also largely influenced by the constraint test setup. These results suggest that caution should be used when comparing reported results between bench tests that use different fixtures and that standardization of testing methods is needed in this field.

Surgical timing for torsional ankle fractures is not associated with post-operative complications in patients with type II diabetes mellitus.

INTRODUCTION: Surgical stabilization of ankle fractures is one of the most commonly performed procedures in orthopedics, but these injuries can prove difficult to manage in patients with type II diabetes mellitus (DMII). The goal of this study is to determine if a correlation exists between surgical timing and complication rates among diabetic patients with ankle fractures. METHODS: This is a retrospective case-control study spanning from 2012 to 2019 including patients with DMII undergoing operative fixation for ankle fractures. The primary independent variable was surgical timing and the primary dependent variable was the rate of post-operative complications. RESULTS: The overall complication rate was 25.5% with 60% of these patients requiring repeat surgical intervention. The most common complication was superficial surgical-site infection. There was no significant difference in surgical timing between patients experiencing post-operative complication compared to those who did not. CONCLUSION: Among patients with DMII, we failed to show a correlation between surgical timing and post-operative complication.

Distal Radius Fractures in Diabetic Patients: An Analysis of Surgical Timing and Other Factors That Affect Complication Rate.

BACKGROUND: While not studied for distal radius fractures, the effect of surgical timing on complication rate has been extensively analyzed in the treatment of pilon fractures. The primary aim of this study was to identify any effect surgical timing has on postoperative complication rates after surgical fixation of distal radius fractures in diabetic patients. METHODS: All patients who underwent surgical fixation of distal radius fractures at a single suburban academic hospital between 2012 and 2019 were reviewed. For each patient, demographics, comorbidities, injury details, fixation method, and postoperative complications were noted. The effect surgical delay, among other factors, had on complication rate in diabetic and nondiabetic patients was explored. RESULTS: Overall, 124 diabetic and 371 nondiabetic distal radius fractures were included. While diabetics had a statistically higher rate of total complications (21.0 vs. 13.5%, P = .045) but similar major complications requiring surgery (P = .12), there was no difference in surgical delay between groups among patients who had total (P = .31) or major (P = .69) complications. Surgical timing was not a risk factor for total (P = .50) or major complications (P = .32) in diabetic fracture bivariate or multivariate analysis. Only younger age and higher energy injuries were significant risk factors for total complications in bivariate (P = .02, P = .03) and multivariate (P = .04, P < .05) analysis. CONCLUSION: Complication rates after surgically stabilized distal radius fractures in diabetic patients are higher than in nondiabetic patients. However, this rate is not affected by surgical timing. Instead, surgeons should consider factors such as diabetic control in an effort to maximize outcomes and decrease complications. LEVEL OF EVIDENCE: Prognostic Level III.

International Orthopaedic Volunteer Opportunities in Low and Middle-Income Countries.

ABSTRACT: Globally, the burden of musculoskeletal conditions continues to rise, disproportionately affecting low and middle-income countries (LMICs). The ability to meet these orthopaedic surgical care demands remains a challenge. To help address these issues, many orthopaedic surgeons seek opportunities to provide humanitarian assistance to the populations in need. While many global orthopaedic initiatives are well-intentioned and can offer short-term benefits to the local communities, it is essential to emphasize training and the integration of local surgeon-leaders. The commitment to developing educational and investigative capacity, as well as fostering sustainable, mutually beneficial partnerships in low-resource settings, is critical. To this end, global health organizations, such as the Consortium of Orthopaedic Academic Traumatologists (COACT), work to promote and ensure the lasting sustainability of musculoskeletal trauma care worldwide. This article describes global orthopaedic efforts that can effectively address musculoskeletal care through an examination of 5 domains: clinical care, clinical research, surgical education, disaster response, and advocacy.

Mechanical characterization of bone quality in distal femur fractures using pre-operative computed tomography scans.

BACKGROUND: Mechanical testing of implant constructs designed to treat distal femur fractures has been hampered by a lack of clinical data on the biomechanical properties of the distal femur in patients who sustain these fractures. Therefore, the purpose of this study was to use quantitative computed tomography (qCT) to investigate the mechanical characteristics of fractured distal femurs to inform the selection of synthetic materials for biomechanical testing. METHODS: Distal femur fractures treated at a Level I trauma center were retrospectively reviewed and 43 cases with preoperative CT scans were identified for analysis. Scans were segmented and each bone fragment was reconstructed as a 3D model. The Young's modulus of the distal femur was determined from voxel-based radiodensity. FINDINGS: Median patient age was 72 years (IQR = 57-81), with 26% males and 74% females. Young's modulus in the distal femur was negatively correlated with patient age (R2 = 0.50, p < 0.001). The distribution of patient-specific modulus values was also compared with the compressive modulus ranges for graded polyurethane foams according to ASTM F1839. Bone quality ranged from Grade 25 in younger individuals to Grade 5 in older individuals. CONCLUSION: No single grade of synthetic polyurethane foam can be selected to model all clinically important scenarios for biomechanical testing of distal femur fracture fixation devices. Rather, this data can be used to select an appropriate material for a given clinical scenario. A Grade 25 foam is appropriate for implant longevity, whereas for implant stability, Grades 5-15 are more appropriate.

The Effect of an Orthopedic Hand Surgeon's Attire on Patient Confidence and Trust.

Background: Multiple studies have concluded that patients are more likely to understand and trust physicians who dress in more formal attire (shirt and tie) as opposed to casual attire (t-shirts and jeans). The white coat has repeatedly been reported as a major source of trust and confidence in a patient's eyes. Methods: This study explores the effect an orthopedic hand surgeon's attire has on a patient's perception of their surgeon's clinical values. All patients 18 years of age and older who visited our orthopedic hand surgeon's suburban outpatient practice were asked to participate in our survey-based study. Results: Ninety-seven surveys were completed and included. A majority of our responders are female (n = 59, 60.8%), Caucasian (n = 83, 85.6%) between the ages of 55 and 74 years (n = 40, 41.2%), currently employed (n = 59, 60.8%) with private health insurance (n = 69, 71.1%), and married (n = 64, 66.0%). Patients rated male and female hand surgeons wearing a white coat highest using the Likert scale and when asked about their perceived clinical qualities. Patients consistently poorly rated their surgeons wearing casual attire. Patients did note that the white coat, or any specific attire, was not necessary during the initial encounter to build a strong patient-surgeon relationship. Finally, goatees and beards do not positively or negatively impact a surgeon's patient-constructed image. Conclusions: Combining strong clinical skills with appropriate clinical attire highlighted by the physician wearing a white coat appears to be an effective way to enhance patient satisfaction while ultimately gaining the trust and respect needed to properly care for patients.

Patient Comprehension and Compliance Survey to Assess Postoperative Pain Regimens in the Orthopaedic Trauma Population.

OBJECTIVE: This study aims to determine the groups of patients who are at risk for noncompliance and misunderstanding of their pain regimen. DESIGN: Survey-based cohort study. SETTING: Suburban Level-I trauma center. PATIENTS/PARTICIPANTS: A total of 171 patients between the ages of 18-89 years who underwent surgical fixation of fractures involving the pelvis, long bones, or periarticular regions of the knee, ankle, elbow, and wrist. MAIN OUTCOME MEASUREMENTS: Patients who cannot accurately reproduce their prescribed pain medication list and patients who modify this pain medication regimen were analyzed by age, employment status, income level, education level, time between surgery and follow-up, and whether pain interfered with activities of daily living. RESULTS: Overall, 147 patients completed the survey. Seventy percent (n = 114) of patients could not accurately reproduce their pain medication regimen, regardless of age, employment status, income level, education level, time between surgery and follow-up, and whether pain interfered with activities of daily living. Patients (61.2%; n = 90), regardless of the 6 aforementioned demographic factors, also admitted to modifying their pain medication regimen with non-prescribed medications, with 55.8% (n = 82) of patients adding over-the-counter medications to surgeon-prescribed narcotic medications. CONCLUSIONS: Misunderstanding and noncompliance of surgeon-prescribed pain regimens are prevalent across all patient demographics. Knowledge of the potential effects these augmentative medications can have on fracture healing and any drug-drug interactions that may arise is an important aspect of patient postoperative care. Surgeons must be wary of these trends and screen for any unintended side effects a patient's pain regimen may have. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

A Comprehensive Framework for International Medical Programs: A 2017 consensus statement from the American College of Academic International Medicine.

The American College of Academic International Medicine (ACAIM) represents a group of clinicians who seek to promote clinical, educational, and scientific collaboration in the area of Academic International Medicine (AIM) to address health care disparities and improve patient care and outcomes globally. Significant health care delivery and quality gaps persist between high-income countries (HICs) and low-and-middle-income countries (LMICs). International Medical Programs (IMPs) are an important mechanism for addressing these inequalities. IMPs are international partnerships that primarily use education and training-based interventions to build sustainable clinical capacity. Within this overall context, a comprehensive framework for IMPs (CFIMPs) is needed to assist HICs and LMICs navigate the development of IMPs. The aim of this consensus statement is to highlight best practices and engage the global community in ACAIM's mission. Through this work, we highlight key aspects of IMPs including: (1) the structure; (2) core principles for successful and ethical development; (3) information technology; (4) medical education and training; (5) research and scientific investigation; and (6) program durability. The ultimate goal of current initiatives is to create a foundation upon which ACAIM and other organizations can begin to formalize a truly global network of clinical education/training and care delivery sites, with long-term sustainability as the primary pillar of international inter-institutional collaborations.

Management of Distal Femur Fractures in Adults: An Overview of Options.

Surgical treatment of periarticular and intra-articular fractures of the distal femur pose a significant challenge to the orthopedic surgeon. The primary goal of surgical treatment remains: restoration of the articular surface to the femoral shaft, while maintaining enough stability and alignment to enable early range of motion and rehabilitation. With appropriate surgical planning, these injuries can be managed with a variety of methods and techniques, while taking into account patients' functional goals, fracture characteristics, health comorbidities, bone quality, and risk of malunion and nonunion.

The treatment of periprosthetic femur fractures after total knee arthroplasty.

Periprosthetic femur fractures after total knee arthroplasty are a rising concern; however, when properly diagnosed, they can be managed nonoperatively or operatively in the form of locking plate fixation, intramedullary nailing, and arthroplasty. The degree of osteoporosis, stability of the femoral implant, and goals of the patient are a few critical variables in determining the ideal treatment. Despite excellent outcomes from each of these operative choices, the risk of nonunion, malunion, instability, and refracture cannot be ignored.