Animal models for rotator cuff repair

Abstract

Rotator cuff (RC) injuries represent a significant source of pain, functional impairment, and morbidity. The large disease burden of RC pathologies necessitates rapid development of research methodologies to treat these conditions. Given their ability to model anatomic, biomechanical, cellular, and molecular aspects of the human RC, animal models have played an indispensable role in reducing injury burden and advancing this field of research for many years. The development of animal models in the musculoskeletal (MSK) research arena is uniquely different from that in other fields in that the similarity of macrostructures and functions is as critical to replicate as cellular and molecular functions. Traditionally, larger animals have been used because of their anatomic similarity to humans and the ease of carrying out realistic surgical procedures. However, refinement of current molecular methods, introduction of novel research tools, and advancements in microsurgical techniques have increased the applicability of small animal models in MSK research. In this paper, we review RC animal models and emphasize a murine model that may serve as a valuable instrument for future RC tendon repair investigations.

Kartogenin Enhances Collagen Organization and Mechanical Strength of the Repaired Enthesis in a Murine Model of Rotator Cuff Repair

“…A higher Δb indicates superior collagen fiber organization. 15 All histomorpho-metric analyses were performed in a blinded fashion by 2 independent reviewers (Y.N., S.W.). The intraclass correlation coefficient (2,1) between the 2 reviewers was 0.81, 0.91, and 0.62 for cellularity, fibrocartilage, and collagen fiber organization analysis, respectively.…”

Cell therapy to improve regeneration of skeletal muscle injuries

“…The blunt, non‐penetrating impact model has been widely used to mimic contusion injuries and involves the dropping of a metallic object (usually spherical or cylindrical) of a defined mass from a certain height guided by a hollow tube directly onto the exposed muscle tissue . Laceration is another type of muscle injury that is conveniently replicated in animal models . A laceration injury occurs owing to a direct, penetrating trauma to the tissue by a sharp object and is usually associated with accidents, collisions, and military injuries .…”

“…66,67 Laceration is another type of muscle injury that is conveniently replicated in animal models. 68,69 A laceration injury occurs owing to a direct, penetrating trauma to the tissue by a sharp object and is usually associated with accidents, collisions, and military injuries. 70 This injury essentially splits the muscle tissue, causing damage to myofibers, blood vessels, nerves, and connective tissue and is accompanied by a large haematoma formation and substantial fibrosis.…”

<p>Promoting tendon to bone integration using graphene oxide-doped electrospun poly(lactic-co-glycolic acid) nanofibrous membrane</p>

“…Notably, this study was conducted on a rabbit model rather than the complex condition of a tendon in a human. 55,56 Another limitation of our study is that the last time point we selected is 12 weeks after the operation; it is desirable to carry out histological observation of the tendon to bone junctions even up to 1 year after surgery. 20 Finally, the underlying mechanisms of the promotion of BMSC differentiation and the enhancement of the tendon to bone healing by the nanostructured PLGA-GO membranes are unknown and need to be clarified.…”