Generating New Meniscus Therapies via Recent Breakthroughs in Development, Model Systems, and Clinical Diagnostics.

Over 850,000 surgeries are performed to treat meniscal injuries each year in the United States. Even with repair, patients are likely to develop osteoarthritis (OA) within the next two decades. There is a pressing clinical need to improve meniscal repair procedures to restore tissue function and prevent joint degeneration later in life.

Arthroscopic synovitis severity scoring in canine stifles with cranial cruciate ligament disease.

Objective: To investigate the occurrence, degree, and risk factors associated with arthroscopic stifle joint synovitis in dogs with cranial cruciate ligament (CCL) disease.

Study Design: Retrospective, observational study.

Sample Population: Canine CCL disease (n = 163) from 149 dogs and their arthroscopic video recordings.

Interleukin receptor therapeutics attenuate inflammation in canine synovium following cruciate ligament injury.

Objective: In the knee, synovial fibrosis after ligamentous injury is linked to progressive joint pain and stiffness. The objective of this study was to evaluate changes in synovial architecture, mechanical properties, and transcriptional profiles following naturally occurring cruciate ligament injury in canines and to test potential therapeutics that target drivers of synovial inflammation and fibrosis.

Design: Synovia from canines with spontaneous cruciate ligament tears and from healthy knees were assessed via histology (n = 10/group) and micromechanical testing (n = 5/group) to identify changes in tissue architecture and stiffness.

Transient inhibition of meniscus cell migration following acute inflammatory challenge.

Meniscus tears represent a common orthopedic injury that often requires surgery to restore pain-free function. The need for surgical intervention is due, in part, to the inflammatory and catabolic environment that inhibits meniscus healing after injury. In other organ systems, healing is dependent on the migration of cells to the site of injury; however, in the meniscus, it is currently unknown how the microenvironment dictates cell migration in the postinjury inflamed setting.

Six-Month Outcomes of Clinically Relevant Meniscal Injury in a Large-Animal Model.

Background: The corrective procedures for meniscal injury are dependent on tear type, severity, and location. Vertical longitudinal tears are common in young and active individuals, but their natural progression and impact on osteoarthritis (OA) development are not known. Root tears are challenging and they often indicate poor outcomes, although the timing and mechanisms of initiation of joint dysfunction are poorly understood, particularly in large-animal and human models.

Photobiomodulation does not influence maturation and mildly improves functional healing of mouse achilles tendons.

Tendon rupture can occur at any age and is commonly treated nonoperatively, yet can result in persisting symptoms. Thus, a need exists to improve nonoperative treatments of injured tendons. Photobiomodulation (PBM) therapy has shown promise in the clinic and is hypothesized to stimulate mitochondrial-related metabolism and improve healing.

Partial-width injuries of the rat rotator cuff heal with fibrosis.

Purpose: Identify the healing outcomes following a partial-width, full-thickness injury to the rotator cuff tendon-bone attachment and establish if the adult attachment can regenerate the morphology of the healthy attachment.

Hypothesis: We hypothesized that a partial-width injury to the attachment would heal via fibrosis and bone remodeling, resulting in increased cellularity and extra-cellular matrix deposition, reduced bone volume (BV), osteoclast presence, and decreased collagen organization compared to shams.

Materials And Methods: A partial-width injury was made using a biopsy punch at the center one-third of the rat infraspinatus attachment.

Strain Distribution of Intact Rat Rotator Cuff Tendon-to-Bone Attachments and Attachments With Defects.

This study aimed to experimentally track the tissue-scale strains of the tendon-bone attachment with and without a localized defect. We hypothesized that attachments with a localized defect would develop strain concentrations and would be weaker than intact attachments. Uniaxial tensile tests and digital image correlation were performed on rat infraspinatus tendon-to-bone attachments with defects (defect group) and without defects (intact group).