Wheel Running Exacerbates Joint Damage after Meniscal Injury in Mice, but Does Not Alter Gait or Physical Activity Levels.

Purpose: Exercise and physical activity are recommended to reduce pain and improve joint function in patients with knee osteoarthritis (OA). However, exercise has dose effects, with excessive exercise accelerating OA development and sedentary behaviors also promoting OA development. Prior work evaluating exercise in preclinical models has typically used prescribed exercise regimens; however, in-cage voluntary wheel running creates opportunities to evaluate how OA progression affects self-selected physical activity levels.

Effects of Repeat Test Exposure on Gait Parameters in Naïve Lewis Rats.

Rodent gait analysis has emerged as a powerful, quantitative behavioral assay to characterize the pain and disability associated with movement-related disorders. In other behavioral assays, the importance of acclimation and the effect of repeated testing have been evaluated. However, for rodent gait analysis, the effects of repeated gait testing and other environmental factors have not been thoroughly characterized.

African Spiny Mice () Exhibit Mild Osteoarthritis Following Meniscal Injury.

Objective: Hyaline cartilage has limited innate healing abilities and hyaline cartilage loss is a hallmark of osteoarthritis (OA). Animal models can provide important insights into cartilage regeneration potential. One such animal model, the African spiny mouse (), is capable of regenerating skin, skeletal muscle, and elastic cartilage.

Recommendations for the analysis of rodent gait data to evaluate osteoarthritis treatments.

Behavioral assays of animal pain and disability can increase the clinical relevance of a preclinical study. However, pain and symptoms are difficult to measure in preclinical models. Because animals often alter their movement patterns to reduce or avoid joint pain, gait analysis can be an important tool for quantifying OA-related symptoms in rodents.

Age alters gait compensations following meniscal injury in male rats.

With age, susceptibility to osteoarthritis (OA) and OA-related pain and disability increases. Like in OA patients, gait patterns in rodent OA models shift to protect the injured limb during loading. However, unlike in OA patients, it is unknown how age affects gait changes in rodent OA models.

Non-Destructive Spatial Mapping of Glycosaminoglycan Loss in Native and Degraded Articular Cartilage Using Confocal Raman Microspectroscopy.

Articular cartilage is a collagen-rich tissue that provides a smooth, lubricated surface for joints and is also responsible for load bearing during movements. The major components of cartilage are water, collagen, and proteoglycans. Osteoarthritis is a degenerative disease of articular cartilage, in which an early-stage indicator is the loss of proteoglycans from the collagen matrix.

The effects of age on the severity of joint damage and intra-articular inflammation following a simulated medial meniscus injury in 3, 6, and 9 month old male rats.

: Aging is a known risk factor for osteoarthritis (OA). Several transgenic rodent models have been used to investigate the effects of accelerated or delayed aging in articular joints. However, age-effects on the progression of post-traumatic OA are less frequently evaluated.