The Importance of Medial Patellar Shape as a Risk Factor for Recurrent Patellar Dislocation in Adults.

Background: Research on the cause of lateral patellar dislocation (LPD) has focused on trochlear morphologic parameters, joint alignment, and patellofemoral soft tissue forces. A paucity of information is available regarding how patellar morphologic parameters influence the risk for LPD.

Purpose/hypothesis: The purpose was to assess whether patellar morphology is a risk factor for recurrent LPD.

Catastrophic Sports Injuries: Causation and Prevention.

➤ Catastrophic injuries in U.S. high school and college athletes are rare but devastating injuries.

Using bilateral data in controls and patients with bilateral and unilateral pathology requires increased scrutiny.

In many aspects of human research, capturing multiple measures from the same participant is common due to the symmetric nature of the human body (e.g., two eyes, ten fingers, two legs, etc.

Neuromechanical Properties of the Vastus Medialis and Vastus Lateralis in Adolescents With Patellofemoral Pain.

Background: An alteration in the force distribution among quadriceps heads is one possible underlying mechanism of patellofemoral pain. However, this hypothesis cannot be directly tested as there are currently no noninvasive experimental techniques to measure individual muscle force or torque in vivo in humans. In this study, the authors considered a combination of biomechanical and muscle activation measures, which enabled us to estimate the mechanical impact of the vastus medialis (VM) and vastus lateralis (VL) on the patella.

Semi-automatic muscle segmentation in MR images using deep registration-based label propagation.

Fully automated approaches based on convolutional neural networks have shown promising performances on muscle segmentation from magnetic resonance (MR) images, but still rely on an extensive amount of training data to achieve valuable results. Muscle segmentation for pediatric and rare diseases cohorts is therefore still often done manually. Producing dense delineations over 3D volumes remains a time-consuming and tedious task, with significant redundancy between successive slices.

Mechanism of non-contact ACL injury: OREF Clinical Research Award 2021.

Anterior cruciate ligament (ACL) ruptures significantly impact athletes in terms of return to play and loss of long-term quality of life. Before the onset of this study, understanding the mechanism of ACL injury was limited. Thus, the primary focus of this manuscript is to describe our multi-faceted approach to uncovering the mechanism of noncontact ACL injury (NC-ACLI) with the goal of developing preventive strategies.

Automatic quadriceps and patellae segmentation of MRI with cascaded U -Net and SASSNet deep learning model.

Purpose: Automatic muscle segmentation is critical for advancing our understanding of human physiology, biomechanics, and musculoskeletal pathologies, as it allows for timely exploration of large multi-dimensional image sets. Segmentation models are rarely developed/validated for the pediatric model. As such, autosegmentation is not available to explore how muscle architectural changes during development and how disease/pathology affects the developing musculoskeletal system.

Patellofemoral kinematics in patellofemoral pain syndrome: The influence of demographic factors.

Due to the multifactorial nature of patellofemoral pain, it is often difficult to identify an individual patient's exact cause of pain. Understanding how demographic variability influences these various factors will support improved consensus in regards to the etiology of PF pain. Thus, in this retrospective study, we tested the hypothesis that sex, height, weight, body mass index (BMI), and age influence the determination of between-groups differences in PF kinematics.

Adolescents and adults with patellofemoral pain exhibit distinct patellar maltracking patterns.

Background: Chronic idiopathic patellofemoral pain is associated with patellar maltracking in both adolescents and adults. To accurately target the underlying, patient-specific etiology, it is crucial we understand if age-of-pain-onset influences maltracking.

Methods: Twenty adolescents (13.

A Word of Caution for Future Studies in Patellofemoral Pain: A Systematic Review With Meta-analysis.

Background: Patellar maltracking is widely accepted as an underlying mechanism of patellofemoral pain. However, methodological differences in the literature hinder our ability to generate a universal quantitative definition of pathological patellofemoral kinematics (patellar maltracking) in patellofemoral pain, leaving us unable to determine the cause of patellofemoral pain.

Purpose: To systematically review the literature to provide evidence regarding the influence of confounding variables on patellofemoral kinematics.

Healthy versus pathological learning transferability in shoulder muscle MRI segmentation using deep convolutional encoder-decoders.

Fully-automated segmentation of pathological shoulder muscles in patients with musculo-skeletal diseases is a challenging task due to the huge variability in muscle shape, size, location, texture and injury. A reliable automatic segmentation method from magnetic resonance images could greatly help clinicians to diagnose pathologies, plan therapeutic interventions and predict interventional outcomes while eliminating time consuming manual segmentation. The purpose of this work is three-fold.

Patellofemoral Pain in Adolescents: Understanding Patellofemoral Morphology and Its Relationship to Maltracking.

Background: Developing bone is highly adaptable and, as such, is susceptible to pathological shape deformation. Thus, it is imperative to quantify if changes in patellofemoral morphology are associated with adolescent-onset patellofemoral pain, as a pathway to improve our understanding of this pain's etiology.

Purpose: To quantify and compare patellofemoral morphology in adolescent patients with patellofemoral pain with matched healthy adolescent controls and determine if a relationship exists between patellofemoral shape and kinematics (measured during active flexion-extension).

Fully automated patellofemoral MRI segmentation using holistically nested networks: Implications for evaluating patellofemoral osteoarthritis, pain, injury, pathology, and adolescent development.

Purpose: Our clinical understanding of the relationship between 3D bone morphology and knee osteoarthritis, as well as our ability to investigate potential causative factors of osteoarthritis, has been hampered by the time-intensive nature of manually segmenting bone from MR images. Thus, we aim to develop and validate a fully automated deep learning framework for segmenting the patella and distal femur cortex, in both adults and actively growing adolescents.

Methods: Data from 93 subjects, obtained from on institutional review board-approved protocol, formed the study database.

Increased Patellar Volume/Width and Decreased Femoral Trochlear Width Are Associated With Adolescent Patellofemoral Pain.

Background: Patellofemoral pain is one of the most common forms of knee arthralgia in adolescent females. Unlike in adults, in whom the etiology of patellofemoral pain is considered to be multifactorial (eg, altered bone shape and musculoskeletal dynamics), the etiology of adolescent patellofemoral pain has been historically attributed to overuse. Although it is highly plausible that adolescent patellofemoral pain results from excessive maltracking, as suggested by recent research, an increase in patellar, relative to femoral, size could also contribute to patellofemoral pain through altered cartilage stresses/strains, resulting in overloading of the subchondral bone.

Advancing quantitative techniques to improve understanding of the skeletal structure-function relationship.

Although all functional movement arises from the interplay between the neurological, skeletal, and muscular systems, it is the skeletal system that forms the basic framework for functional movement. Central to understanding human neuromuscular development, along with the genesis of musculoskeletal pathologies, is quantifying how the human skeletal system adapts and mal-adapts to its mechanical environment. Advancing this understanding is hampered by an inability to directly and non-invasively measure in vivo strains, stresses, and forces on bone.

Shoulder muscle atrophy and its relation to strength loss in obstetrical brachial plexus palsy.

Background: Treatment/prevention of shoulder muscle strength imbalances are major therapeutic goals for children with obstetrical brachial plexus palsy. The study aims were to characterize muscle atrophy in children/adolescents with unilateral obstetrical brachial plexus palsy, to quantify the agonist-antagonist muscle volume balance and the association between muscle volume and strength.

Methods: Eight boys and four girls (age=12.

Normalized patellofemoral joint reaction force is greater in individuals with patellofemoral pain.

Patellofemoral pain is a disabling, highly prevalent pathology. Altered patellofemoral contact forces are theorized to contribute to this pain. Musculoskeletal modeling has been employed to better understand the etiology of patellofemoral pain.

The Relationship of Static Tibial Tubercle-Trochlear Groove Measurement and Dynamic Patellar Tracking.

Background: The tibial tubercle to trochlear groove (TT-TG) distance is used for screening patients with a variety of patellofemoral joint disorders to determine who may benefit from patellar medialization using a tibial tubercle osteotomy. Clinically, the TT-TG distance is predominately based on static imaging with the knee in full extension; however, the predictive ability of this measure for dynamic patellar tracking patterns is unknown.

Purpose: To determine whether the static TT-TG distance can predict dynamic lateral displacement of the patella.

Patellar Maltracking Persists in Adolescent Females With Patellofemoral Pain: A Longitudinal Study.

Background: Patellofemoral pain is one of the most common conditions seen in sports medicine practices, particularly among adolescent females. However, the natural history of the underlying pathology in patellofemoral pain during puberty remains poorly understood.

Purpose: The purpose of this longitudinal study is to assess changes in patellar maltracking patterns in subjects with patellofemoral pain as they mature from mid- to late adolescence.

The Tibial Tubercle-Trochlear Groove Distance Is Greater in Patients With Patellofemoral Pain: Implications for the Origin of Pain and Clinical Interventions.

Background: The distance between the tibial tubercle (TT) and trochlear groove (TT-TG distance) is known to be greater in patients with patellar instability. However, the potential role and prevalence of pathological TT-TG distances in a large cohort of skeletally mature patients with isolated patellofemoral pain (PFP) are not clear.

Purpose: To determine if the mean TT-TG distance is greater in patients with PFP, who lack a history of patellar dislocations, knee trauma, or osteoarthritis, relative to healthy controls.

Patellofemoral Kinematics and Tibial Tuberosity-Trochlear Groove Distances in Female Adolescents With Patellofemoral Pain.

Background: Patellofemoral pain (PFP) is a prevalent disorder among female adolescents. Overuse is frequently cited as the cause of pain for this population. What is currently unclear, however, is if the patella demonstrates abnormal tracking patterns relative to the femoral trochlear groove in female adolescents with PFP.

Video Analysis of Anterior Cruciate Ligament (ACL) Injuries: A Systematic Review.

Background: As the most viable method for investigating in vivo anterior cruciate ligament (ACL) rupture, video analysis is critical for understanding ACL injury mechanisms and advancing preventative training programs. Despite the limited number of published studies involving video analysis, much has been gained through evaluating actual injury scenarios.

Methods: Studies meeting criteria for this systematic review were collected by performing a broad search of the ACL literature with use of variations and combinations of video recordings and ACL injuries.

The effective quadriceps and patellar tendon moment arms relative to the tibiofemoral finite helical axis.

The moment arm is a crucial parameter for understanding musculoskeletal dynamics as it defines how linear muscle force is transformed into a moment. Yet, for the quadriceps tendon this parameter cannot be directly calculated, as the patella creates a dynamic fulcrum. Thus, the effective quadriceps moment arm (EQma) was developed to define the quadriceps force to tibial moment relationship.