The Biomechanical, Biochemical, and Morphological Properties of 19 Human Cadaveric Lower Limb Tendons and Ligaments: An Open-Access Data Set.

Background: Methodological heterogeneity hinders data comparisons across isolated studies of tendon and ligament properties, limiting clinical understanding and affecting the development and evaluation of replacement materials.

Purpose: To create an open-access data set on the morphological, biomechanical, and biochemical properties of clinically important tendons and ligaments of the lower limb, using consistent methodologies, to enable direct tendon/ligament comparisons.

Study Design: Descriptive laboratory study.

Tendon biomechanical properties are altered by storage duration but not freeze-thaw temperatures or cycles.

Tendon allograft and xenograft processing often involves one or more steps of freezing and thawing. As failure strength is an important graft consideration, this study aimed to evaluate effects on failure properties when varying freeze-thaw conditions. Kangaroo tendons, a potential xenograft source, were used to evaluate changes in ultimate tensile strength (UTS), failure strain and elastic modulus after exposure to different freezer-storage temperatures (-20°C vs.

Loss of Grem1-lineage chondrogenic progenitor cells causes osteoarthritis.

Osteoarthritis (OA) is characterised by an irreversible degeneration of articular cartilage. Here we show that the BMP-antagonist Gremlin 1 (Grem1) marks a bipotent chondrogenic and osteogenic progenitor cell population within the articular surface. Notably, these progenitors are depleted by injury-induced OA and increasing age.

Streamlining quantitative joint-wide medial femoro-tibial histopathological scoring of mouse post-traumatic knee osteoarthritis models.

Objectives: Histological scoring remains the gold-standard for quantifying post-traumatic osteoarthritis (ptOA) in animal models, allowing concurrent evaluation of numerous joint tissues. Available systems require scoring multiple sections/joint making analysis laborious and expensive. We investigated if a single section allowed equivalent quantitation of pathology in different joint tissues and disease stages, in three ptOA models.

Disease-modifying interactions between chronic kidney disease and osteoarthritis: a new comorbid mouse model.

Objective: The prevalence of comorbid chronic kidney disease (CKD) and osteoarthritis (OA) is increasing globally. While sharing common risk factors, the mechanism and consequences of concurrent CKD-OA are unclear. The aims of the study were to develop a preclinical comorbid model, and to investigate the disease-modifying interactions.

Multiphasic scaffolds for the repair of osteochondral defects: Outcomes of preclinical studies.

Osteochondral defects are caused by injury to both the articular cartilage and subchondral bone within skeletal joints. They can lead to irreversible joint damage and increase the risk of progression to osteoarthritis. Current treatments for osteochondral injuries are not curative and only target symptoms, highlighting the need for a tissue engineering solution.

Deletion of the chondrocyte glucocorticoid receptor attenuates cartilage degradation through suppression of early synovial activation in murine posttraumatic osteoarthritis.

Objective: Disruption of endogenous glucocorticoid signalling in bone cells attenuates osteoarthritis (OA) in aged mice, however, the role of endogenous glucocorticoids in chondrocytes is unknown. Here, we investigated whether deletion of the glucocorticoid receptor, specifically in chondrocytes, also alters OA progression.

Design: Knee OA was induced by surgical destabilisation of the medial meniscus (DMM) in male 22-week-old tamoxifen-inducible glucocorticoid receptor knockout (chGRKO) mice and their wild-type (WT) littermates (n = 7-9/group).

Loss of -articular cartilage progenitor cells causes osteoarthritis.

Osteoarthritis (OA), which carries an enormous disease burden across the world, is characterised by irreversible degeneration of articular cartilage (AC), and subsequently bone. The cellular cause of OA is unknown. Here, using lineage tracing in mice, we show that the BMP-antagonist () marks a novel chondrogenic progenitor (CP) cell population in the articular surface that generates joint cartilage and subchondral bone during development and adulthood.

Challenging the Perceptions of Human Tendon Allografts: Influence of Donor Age, Sex, Height, and Tendon on Biomechanical Properties.

Background: The use of allograft tendons has increased for primary and revision anterior cruciate ligament reconstruction, but allograft supply is currently limited to a narrow range of tendons and donors up to the age of 65 years. Expanding the range of donors and tendons could help offset an increasing clinical demand.

Purpose: To investigate the effects of donor age, sex, height, and specific tendon on the mechanical properties of a range of human lower leg tendons.

Animal models of osteoarthritis : the benefits and costs of reducing variability.

Cite this article:  2022;11(8):514-517.

Muscle spindles of the multifidus muscle undergo structural change after intervertebral disc degeneration.

Purpose: Proprioceptive deficits are common in low back pain. The multifidus muscle undergoes substantial structural change after back injury, but whether muscle spindles are affected is unclear. This study investigated whether muscle spindles of the multifidus muscle are changed by intervertebral disc (IVD) degeneration in a large animal model.

Osteoarthritis Pathophysiology: Therapeutic Target Discovery may Require a Multifaceted Approach.

Molecular understanding of osteoarthritis (OA) has greatly increased through careful analysis of tissue samples, preclinical models, and large-scale agnostic "-omic" studies. There is broad acceptance that systemic and biomechanical signals affect multiple tissues of the joint, each of which could potentially be targeted to improve patient outcomes. In this review six experts in different aspects of OA pathogenesis provide their independent view on what they believe to be good tractable approaches to OA target discovery.

Diurnal effects of polypharmacy with high drug burden index on physical activities over 23 h differ with age and sex.

Aging, polypharmacy (concurrent use of ≥ 5 medications), and functional impairment are global healthcare challenges. However, knowledge of the age/sex-specific effects of polypharmacy is limited, particularly on daily physical activities. Using continuous monitoring, we demonstrated how polypharmacy with high Drug Burden Index (DBI-cumulative anticholinergic/sedative exposure) affected behaviors over 23 h in male/female, young/old mice.

Consensus for Statements Regarding a Definition for Spinal Osteoarthritis for Use in Research and Clinical Practice: A Delphi Study.

Objective: To determine consensus among an international, multidisciplinary group of experts regarding definitions of spinal osteoarthritis for research and for clinical practice.

Methods: A 15-member, multidisciplinary steering committee generated 117 statements for a 3-round Delphi study. Experts in back pain and/or osteoarthritis were identified and invited to participate.

Monocytes, Macrophages, and Their Potential Niches in Synovial Joints - Therapeutic Targets in Post-Traumatic Osteoarthritis?

Synovial joints are complex structures that enable normal locomotion. Following injury, they undergo a series of changes, including a prevalent inflammatory response. This increases the risk for development of osteoarthritis (OA), the most common joint disorder.

Corrigendum to "Exploring translational gaps between basic scientists, clinical researchers, clinicians, and consumers: Proceedings and recommendations arising from the 2020 mine the gap online workshop" [Osteoarthritis Cartilage Open 29 (2021) 100163].

[This corrects the article DOI: 10.1016/j.ocarto.

Male-Female Differences in the Effects of Age on Performance Measures Recorded for 23 Hours in Mice.

Functional independence is an important aspect of successful aging and differs with age and by sex in humans. Physical performance often declines earlier than other age-associated functional impairments. Rodent models are used to study pharmacological/toxicological effects of human therapies.

Exploring translational gaps between basic scientists, clinical researchers, clinicians, and consumers: Proceedings and recommendations arising from the 2020 mine the gap online workshop.

Objective: To provide a summary of the translational gaps in musculoskeletal research as identified in the Mine the Gap workshop and propose possible solutions.

Methods: The Mine the Gap online workshop was hosted on October 14th and 15th, 2020. Five international panels, each comprised of a clinician, clinical researcher and basic scientist, presented gaps and proposed solutions for the themes of biomechanics, pain, biological measurements, phenotypes and imaging.

Limited utility of novel serological biomarkers in patients newly suspected of having giant cell arteritis.

Aim: Diagnosing and monitoring vascular activity in giant cell arteritis (GCA) is difficult due to the paucity of specific serological biomarkers. We assessed the utility of 8 novel biomarkers in an inception cohort of newly suspected GCA patients.

Method: Consecutive patients were enrolled between May 2016 and December 2017.

Extracellular Vesicles from Mesenchymal Stromal Cells for the Treatment of Inflammation-Related Conditions.

Over the past two decades, mesenchymal stromal cells (MSCs) have demonstrated great potential in the treatment of inflammation-related conditions. Numerous early stage clinical trials have suggested that this treatment strategy has potential to lead to significant improvements in clinical outcomes. While promising, there remain substantial regulatory hurdles, safety concerns, and logistical issues that need to be addressed before cell-based treatments can have widespread clinical impact.

Long-term Effect of a Single Subcritical Knee Injury: Increasing the Risk of Anterior Cruciate Ligament Rupture and Osteoarthritis.

Background: Rupture of the anterior cruciate ligament (ACL) is a well-known risk factor for the development of posttraumatic osteoarthritis (PTOA), but patients with the "same injury" can have vastly different trajectories for the onset and progression of disease. Minor subcritical injuries preceding the critical injury event may drive this disparity through preexisting tissue pathologies and sensory changes.

Purpose: To investigate the role of subcritical injury on ACL rupture risk and PTOA through the evaluation of pain behaviors, joint mechanics, and tissue structural change in a mouse model of knee injury.

Generation of a miR-26b stem-loop knockout human iPSC line, MCRIi019-A-1, using CRISPR/Cas9 editing.

miR-26b has been implicated in a wide range of human diseases, including cancer, diabetes, heart disease, Alzheimer's disease and osteoarthritis. To provide a tool to explore the importance of miR-26b in this broad context, we have generated and characterized a homozygous miR-26b stem-loop knockout human iPSC line. This gene-edited line exhibited a normal karyotype, expressed pluripotency markers and differentiated into cells representative of the three embryonic germ layers.

OATargets: a knowledge base of genes associated with osteoarthritis joint damage in animals.

Objectives: To collate the genes experimentally modulated in animal models of osteoarthritis (OA) and compare these data with OA transcriptomics data to identify potential therapeutic targets.

Methods: PubMed searches were conducted to identify publications describing gene modulations in animal models. Analysed gene expression data were retrieved from the SkeletalVis database of analysed skeletal microarray and RNA-Seq expression data.

Identification of the skeletal progenitor cells forming osteophytes in osteoarthritis.

Objectives: Osteophytes are highly prevalent in osteoarthritis (OA) and are associated with pain and functional disability. These pathological outgrowths of cartilage and bone typically form at the junction of articular cartilage, periosteum and synovium. The aim of this study was to identify the cells forming osteophytes in OA.