Design and validation of finite element models for the assessment of post-fixation distal femur fracture motion.

Fracture site motion is thought to play an important role in the healing of complex fractures of the distal femur via mechanotransduction. Measuring this motion in vivo is challenging, and this has led researchers to turn to finite element modeling approaches to gain insights into the mechanical environment at the fracture site. Developing a systematic understanding of the effect of different model choices for distal femur fractures may allow more accurate prediction of fracture site motion from these types of simulations.

Geriatric femur fractures: Index fracture pattern is associated with the risk of subsequent peri-implant fracture.

Introduction: Following an index femoral fragility fracture, patients are at risk of a subsequent peri-implant fracture. Management of these injuries are further complicated by patient factors and multi-institutional care. This study quantifies such events and compare rate of identification between in-system and out-of-system patients.

Stable Lateral Compression Pelvic Ring Injury Requiring Operative Treatment due to Bladder Impingement: A Case Report.

Case: A 25-year-old man sustained a stable lateral compression Type I (LC I) pelvic ring injury upon missing the landing of a downhill ski jump. He presented with painful voiding from a displaced bony fragment, partially impaling the bladder wall. With operative fixation of the fracture and urologic co-management, the patient had excellent outcomes at 1-year follow-up.

For Surgically Treated Geriatric Acetabular Fractures, Longer Duration between Admission and Surgery Is Associated with an Increase in Post-operative Complications: A Study Using the National Trauma Data Bank.

Introduction: The purpose of this study was to determine whether time from hospital admission to surgery is associated with inpatient complications and mortality for geriatric patients undergoing surgical treatment of acetabular fractures.

Methods: This was a retrospective cohort study using the National Trauma Data Bank from 2016 to 2018 of patients presenting to level I through IV trauma centers in the United States. All patients aged 60 years or older with acetabular fractures requiring surgical treatment were included.

Thermodynamic properties and switching dynamics of perpendicular shape anisotropy MRAM.

The power consumption of modern random access memory (RAM) has been a motivation for the development of low-power non-volatile magnetic RAM (MRAM). Based on a CoFeB/MgO magnetic tunnel junction, MRAM must satisfy high thermal stability and a low writing current while being scaled down to a sub-20 nm size to compete with the densities of current RAM technology. A recent development has been to exploit perpendicular shape anisotropy along the easy axis by creating tower structures, with the free layers' thickness (along the easy axis) being larger than its width.

Sagittal Angulation and the Treatment of Geriatric Femoral Neck Fractures: Time to Update our Classification Systems.

Objectives: Inconsistent outcomes have been reported for percutaneous fixation of Garden I/II femoral neck fractures in geriatric patients. It was hypothesized that accounting for variable follow-up would better estimate the failure rate of percutaneous fixation with and without significant sagittal angulation.

Design: Retrospective.

Treatment of Vancouver B2 Femur Fractures With Open Reduction Internal Fixation Versus Revision Arthroplasty.

Background Vancouver B2 periprosthetic femur fractures have traditionally been treated with revision arthroplasty. However, there is increasing evidence that open reduction and internal fixation (ORIF) may be a valid alternative treatment strategy. The purpose of this study was to compare the outcomes of ORIF versus revision arthroplasty for the treatment of Vancouver B2 fractures and evaluate the influence of the treating surgeon's fellowship training on treatment selection.

Bridge Plate Fixation of Distal Femur Fractures: Defining Deficient Radiographic Callus Formation and Its Associations.

Objective: To determine whether deficient early callus formation can be defined objectively based on the association with an eventual nonunion and specific patient, injury, and treatment factors.

Methods: Final healing outcomes were documented for 160 distal femur fractures treated with locked bridge plate fixation. Radiographic callus was measured on postoperative radiographs until union or nonunion had been declared by the treating surgeon.

Sagittal deformity of Garden type I and II geriatric femoral neck fractures is frequently misclassified by lateral radiographs.

Unlabelled: The objective of this study was to determine the validity and inter-rater reliability of radiographic assessment of sagittal deformity of femoral neck fractures.

Design: This is a retrospective cohort study.

Setting: Level 1 trauma center.

Immediate Fixation of Acetabular Fractures Through an Anterior Approach Does Not Increase Morbidity or Mortality.

Introduction: Acetabular fractures requiring an anterior approach have historically been delayed, allowing a stable clot to form before creating large surgical exposures. The purpose of this study was to determine whether immediate fixation of acetabular fractures within 24 hours using an anterior approach demonstrates notable difference in blood loss, length of stay (LOS), complications, or mortality compared with acetabular fractures treated after 24 hours.

Methods: Ninety-three patients were optimized for surgery within 24 hours of injury.

Review of human supraspinatus tendon mechanics. Part I: fatigue damage accumulation and failure.

Repetitive stress injuries to the rotator cuff, and particularly the supraspinatus tendon (SST), are highly prevalent and debilitating. These injuries typically occur through the application of cyclic load below the threshold necessary to cause acute tears, leading to accumulation of incremental damage that exceeds the body's ability to heal, resulting in decreased mechanical strength and increased risk of frank rupture at lower loads. Consistent progression of fatigue damage across multiple model systems suggests a generalized tendon response to overuse.

Review of human supraspinatus tendon mechanics. Part II: tendon healing response and characterization of tendon health.

Overuse injuries of the rotator cuff, particularly of the supraspinatus tendon (SST), are highly prevalent and debilitating in work, sport, and daily activities. Despite the clinical significance of these injuries, there remains a large degree of uncertainty regarding the pathophysiology of injury, optimal methods of nonoperative and operative repair, and how to adequately assess tendon injury and healing. The tendon response to fatigue damage resulting from overuse is different from that of acute rupture and results in either an adaptive (healing) or a maladaptive (degenerative) response.

Mobility-Maintaining Facet Arthroplasty of the Lumbar Spine With the Second-Generation TOPS System: A Case Series.

Background: Lumbar spinal stenosis results from spinal canal narrowing and can lead to pain and dysfunction. Until recently, surgical treatment for lumbar spinal stenosis requiring an extensive decompression, with or without spondylolisthesis, had to balance pain relief with the long-term risks of spinal instability after decompression and adjacent segment disease (ASD) after spinal fusion. Spinal motion-preserving devices aim to reduce the incidence of ASD after posterolateral fusion and consequent need for revision surgery.

Developing a National Trauma Research Action Plan: Results from the geriatric research gap Delphi survey.

Background: Treating older trauma patients requires a focus on the confluence of age-related physiological changes and the impact of the injury itself. Therefore, the primary way to improve the care of geriatric trauma patients is through the development of universal, systematic multidisciplinary research. To achieve this, the Coalition for National Trauma Research has developed the National Trauma Research Action Plan that has generated a comprehensive research agenda spanning the continuum of geriatric trauma care from prehospital to rehabilitation.

AP pelvis radiograph is insufficient for diagnosis of U-type sacral fractures.

Purpose: We investigated the sensitivity of a screening test for pelvic ring disruption, the AP pelvis radiograph, for clinically serious U-type sacral fractures which merit consultation with an orthopedic trauma specialist and may require transfer to a higher level of care.

Methods: Retrospective clinical cohort of 63 consecutive patients presenting with U-type sacral fractures at one level 1 trauma referral center from January 2006 through December 2019. The sensitivity of the first AP pelvis radiograph obtained on admission, interpreted without reference to antecedent or concomitant pelvis computed tomography (CT) by a radiologist and a panel of three blinded orthopedic traumatologists, was determined against a reference diagnosis made from review of all pelvis radiographs, CT images, operative reports, and clinical documentation.

Distal Femoral Replacement for Fractures Allows for Early Mobilization with Low Complication Rates: A Multicenter Review.

Periprosthetic fractures around a total knee arthroplasty (TKA), comminuted and intra-articular femur fractures, or fracture nonunions in osteoporotic bone represent technically challenging problems. This is particularly true when the fracture involves a loose femoral component or the pattern results in suboptimal fixation potential. These clinical indications often arise in an older and comorbid patient population in whom a principal goal of treatment includes allowing for early mobilization.

Risk factors for failure of limb salvage among veterans with foot ulcers.

Background: There is limited available information to guide early discussions involving limb salvage for patients with non-traumatic foot ulcers. We hypothesized patient, wound and treatment factors identifiable at initial operative treatment would be associated with failure of attempted limb salvage.

Methods: We retrospectively assessed United States military veterans treated operatively for non-traumatic foot ulcers at a Veteran's Administration (VA) hospital from 2008 to 2018.

Clinical and Radiographic Predictors of Nonunion in Open Tibial Shaft Fractures.

Open fracture is a risk factor for nonunion of diaphyseal tibia fractures. Compared with closed injuries, there is a relative lack of scientific knowledge regarding the healing of open tibia fractures. The objective of this study was to investigate which patient, injury, and surgeon-related factors predict nonunion in open tibial shaft fractures.

Evaluation for septic arthritis of the native adult knee is aided by multivariable assessment.

Introduction: Evaluation of suspected septic arthritis of the native adult knee is a common diagnostic dilemma. Pre-aspirate criteria predictive of septic arthritis do not exist for the adult knee and investigations of aspiration results (cell count, differential, gram stain and crystal analysis) have been limited to univariate analyses. Given numerous clinical variables inform the risk of septic arthritis, multivariable analysis that incorporates all clinically available information is critical to allowing accurate decision-making.

Minimally Invasive Medial Plate Osteosynthesis of High-Energy Pediatric Tibia Fractures.

Objectives: We report on the largest series to date of minimally invasive medial plate osteosynthesis of high-energy tibia fractures in skeletally immature patients.

Design: Retrospective.

Setting: Level 1 trauma center.