Evaluation of Mid-term Outcomes Following Shoulder Hemiarthroplasty for Avascular Necrosis of the Humeral Head in Patients 40 Years and Younger.

In order to evaluate postoperative function and failure rates among younger patients undergoing hemiarthroplasty for humeral head avascular necrosis (AVN), data from patients < 40 years treated between December 2008 - January 2018 was retrospectively analyzed. Pain was assessed preoperatively and at final follow up using a visual analogue scale (VAS). The American Shoulder and Elbow Surgeons (ASES) standardized assessment, single assessment numeric evaluation (SANE) score, and patient satisfaction were assessed at final follow up, as well as surgical revision rates.

Is Grit Associated with Burnout and Well-being in Orthopaedic Resident and Faculty Physicians? A Multi-institution Longitudinal Study Across Training Levels.

Background: Grit has been defined as "perseverance and passion for long-term goals" and is characterized by maintaining focus and motivation toward a challenging ambition despite setbacks. There are limited data on the impact of grit on burnout and psychologic well-being in orthopaedic surgery, as well as on which factors may be associated with these variables.

Questions/purposes: (1) Is grit inversely correlated with burnout in orthopaedic resident and faculty physicians? (2) Is grit positively correlated with psychologic well-being in orthopaedic resident and faculty physicians? (3) Which demographic characteristics are associated with grit in orthopaedic resident and faculty physicians? (4) Which demographic characteristics are associated with burnout and psychologic well-being in orthopaedic resident and faculty physicians?

Methods: This study was an institutional review board-approved interim analysis from the first year of a 5-year longitudinal study of grit, burnout, and psychologic well-being in order to assess baseline relationships between these variables before analyzing how they may change over time.

Early to midterm radiographic loosening of the press fit radial head prosthesis.

Background: Radiographic loosening is frequently seen around the radial head (RH) implant. The hypothesis of this study was that radiographic loosening will be more frequent in patients in which the RH prosthesis was implanted due to elbow trauma leading to instability that required lateral collateral ligament repair (LCL).

Materials And Methods: A retrospective review of the patients who had RH implantation between 2012 and 2019 was performed.

Peripheral Nerve Injury After Elbow Arthroscopy: An Analysis of Risk Factors.

Purpose: To identify risk factors associated with peripheral nerve injury after elbow arthroscopy and provide an updated incidence of those complications.

Methods: The elbow arthroscopies that were performed at our institution between 2006 and 2016 were identified. Over a 10-year period, 253 elbow arthroscopies were performed at our institution.

Extensive Hand Thermal and Blast Injury From Electronic Cigarette Explosion: A Case Report.

As the use of electronic cigarettes rises, more reports of injuries related to device explosion are surfacing. Presented here is the case of a 35-year-old man sustaining extensive thermal and blast injuries to his hand when the device exploded while he was holding it. He required multiple surgeries involving groin flap coverage, tendon transfer, and nerve grafting to optimize his postinjury function.

Shoulder Strength Requirements for Upper Limb Functional Tasks: Do Age and Rotator Cuff Tear Status Matter?

Understanding upper limb strength requirements for daily tasks is imperative for early detection of strength loss that may progress to disability due to age or rotator cuff tear. We quantified shoulder strength requirements for 5 upper limb tasks performed by 3 groups: uninjured young adults and older adults, and older adults with a degenerative supraspinatus tear prior to repair. Musculoskeletal models were developed for each group representing age, sex, and tear-related strength losses.

Basic Shoulder Arthroscopy: Beach Chair Patient Positioning.

Shoulder arthroscopy is an orthopaedic procedure that has grown significantly in popularity over the last 40 years. The 2 principle patient positions during shoulder arthroscopy include the beach chair position and lateral decubitus position. This Technical Note details the operating room setup for shoulder arthroscopy in the beach chair position.

The effects of a rotator cuff tear on activities of daily living in older adults: A kinematic analysis.

Rotator cuff tears (RCT) in older individuals may compound age-associated physiological changes and impact their ability to perform daily functional tasks. Our objective was to quantify thoracohumeral kinematics for functional tasks in 18 older adults (mean age=63.3±2.

Quantitative Analysis of Three-Dimensional Distribution and Clustering of Intramuscular Fat in Muscles of the Rotator Cuff.

The purpose of this study was to (1) develop and present a technique to quantitatively assess three-dimensional distribution and clustering of intramuscular fat and (2) use the technique to compare spatial characteristics of intramuscular fat in rotator cuff muscles of older adults with and without a supraspinatus tear. Moran's Index (I), an existing quantitative measure of clustering, was extended for use with MRI to allow comparisons across individuals with different size muscles. Sixteen older adults (>60 years) with (N = 6) and without (N = 10) a degenerative supraspinatus tear participated.

Assessments of Fatty Infiltration and Muscle Atrophy From a Single Magnetic Resonance Image Slice Are Not Predictive of 3-Dimensional Measurements.

Purpose: To (1) determine whether standard clinical muscle fatty infiltration and atrophy assessment techniques using a single image slice for patients with a rotator cuff tear (RCT) are correlated with 3-dimensional measures in older individuals (60+ years) and (2) to determine whether age-associated changes to muscle morphology and strength are compounded by an RCT.

Methods: Twenty older individuals were studied: 10 with an RCT of the supraspinatus (5 men and 5 women) and 10 matched controls. Clinical imaging assessments (Goutallier and Fuchs scores and cross-sectional area ratio) were performed for participants with RCTs.

A randomized trial of diagnostic ultrasound to improve outcomes in focal neuropathies.

Introduction: Neuromuscular ultrasound is valid, reliable, and accurate, but it is not known whether combining it with electrodiagnostic studies leads to better outcomes in individuals with focal neuropathies.

Methods: One hundred twenty individuals with focal neuropathy, based on history, examination, and electrodiagnosis, were enrolled in this study. All patients underwent neuromuscular ultrasound and were randomized to either have their ultrasound results sent to the referring physician or not have them sent.

Can self-report instruments of shoulder function capture functional differences in older adults with and without a rotator cuff tear?

Rotator cuff tears (RCT) are prevalent in older individuals and may compound age-associated functional declines. Our purpose was to determine whether self-report measures of perceived functional ability are valid for older patients with RCT. Twenty five subjects participated (12M/13F; age=63.

Advanced age diminishes tendon-to-bone healing in a rat model of rotator cuff repair.

Background: Advanced patient age is associated with recurrent tearing and failure of rotator cuff repairs clinically; however, basic science studies have not evaluated the influence of aging on tendon-to-bone healing after rotator cuff repair in an animal model. Hypothesis/

Purpose: This study examined the effect of aging on tendon-to-bone healing in an established rat model of rotator cuff repair using the aged animal colony from the National Institute on Aging of the National Institutes of Health. The authors hypothesized that normal aging decreases biomechanical strength and histologic organization at the tendon-to-bone junction after acute repair.

Age-related changes affect rat rotator cuff muscle function.

Background: The influence of age on rotator cuff function and muscle structure remains poorly understood. We hypothesize that normal aging influences rotator cuff function, muscle structure, and regulatory protein expression in an established rat model of aging.

Methods: Seventeen rats were obtained from the National Institute on Aging.

Rotator cuff injuries in professional and recreational athletes.

Professional and recreational athletes involved in contact sports and sports with repetitive overhead motion are at increased risk for rotator cuff tears. Shoulder anatomy, pathology, and biomechanics place unique stress on the rotator cuff tendons during sports activity. Athletes demand effective treatment to quickly return to elite competition.

Age-related degenerative functional, radiographic, and histological changes of the shoulder in nonhuman primates.

Background: Nonhuman primates have similar shoulder anatomy and physiology compared to humans, and may represent a previously underutilized model for shoulder research. This study sought to identify naturally occurring bony and muscular degeneration in the shoulder of nonhuman primates and to assess relationships between structural and functional aspects of the shoulder and measures of physical function of the animals. We hypothesized that age-related degenerative changes in the shoulders of nonhuman primates would resemble those observed in aging humans.

Botulinum Neurotoxin A injections influence stretching of the gastrocnemius muscle-tendon unit in an animal model.

Botulinum Neurotoxin A (BoNT-A) injections have been used for the treatment of muscle contractures and spasticity. This study assessed the influence of (BoNT-A) injections on passive biomechanical properties of the muscle-tendon unit. Mousegastrocnemius muscle (GC) was injected with BoNT-A (n = 18) or normal saline (n = 18) and passive, non-destructive, in vivo load relaxation experimentation was performed to examine how the muscle-tendon unit behaves after chemical denervation with BoNT-A.

The science of rotator cuff tears: translating animal models to clinical recommendations using simulation analysis.

Purpose: The purpose of this article is to review basic science studies using various animal models for rotator cuff research and to describe structural, biomechanical, and functional changes to muscle following rotator cuff tears. The use of computational simulations to translate the findings from animal models to human scale is further detailed.

Methods: A comprehensive review was performed of the basic science literature describing the use of animal models and simulation analysis to examine muscle function following rotator cuff injury and repair in the ageing population.

Evaluation of in vivo rotator cuff muscle function after acute and chronic detachment of the supraspinatus tendon: an experimental study in an animal model.

Background: Surgical repair of large chronic rotator cuff tears can be technically demanding because it requires manipulation of a muscle-tendon unit that is scarred, retracted, and stiffer than normal, all of which contribute to increased tension at the repair site. The purpose of the present study was to characterize the in vivo rotator cuff muscle-tendon unit function after acute and chronic injury at surgically relevant preload tensions.

Methods: Sixty-two Sprague-Dawley rats were divided into a healthy, uninjured (control) group (n = 22), an acute injury group (n = 20), and a chronic injury group (n = 20) and underwent in vivo muscle force testing and electromyographic testing of the supraspinatus muscle-tendon unit at various preload tensions.

Postural dependence of passive tension in the supraspinatus following rotator cuff repair: a simulation analysis.

Background: Despite surgical advances, repair of rotator cuff tears is associated with 20-70% incidence of recurrent tearing. The tension required to repair the torn tendon influences surgical outcomes and may be dependent on the gap length from torn tendon that must be spanned by the repair. Detailed understanding of forces throughout the range of motion (ROM) may allow surgeons to make evidence-based recommendations for post-operative care.

Contributions of neural tone to in vivo passive muscle--tendon unit biomechanical properties in a rat rotator cuff animal model.

Passive viscoelastic properties of muscle-tendon units are key determinants of intra- and post-operative success. Atrophied, retracted, and stiff muscle-tendon units are technically challenging to manipulate and perform poorly after surgical repair. This study employs botulinum neurotoxin A (BoNT-A)-mediated inhibition of presynaptic acetylcholine release to examine in vivo neural contributions to soft-tissue biomechanical properties.

Hand and body radiation exposure with the use of mini C-arm fluoroscopy.

Purpose: To determine whole body and hand radiation exposure to the hand surgeon wearing a lead apron during routine intraoperative use of the mini C-arm fluoroscope.

Methods: Four surgeons (3 hand attending surgeons and 1 hand fellow) monitored their radiation exposure for a total of 200 consecutive cases (50 cases per surgeon) requiring mini C-arm fluoroscopy. Each surgeon measured radiation exposure with a badge dosimeter placed on the outside breast pocket of the lead apron (external whole body exposure), a second badge dosimeter under the lead apron (shielded whole body exposure), and a ring dosimeter (hand exposure).