Skeletal Muscle
Nassir H. Sabah in Neuromuscular Fundamentals, 2020
The endomysium, perimysium, and epimysium are interconnected together and blend with tendons and aponeuroses. Tendon is a tough, fibrous, whitish, cord-like tissue that connects muscle to bone and is composed of parallel arrays of closely packed fibers that are mostly collagen. The collagen fibers aggregate to form fascicles that are surrounded by connective tissue. Bundles of fascicles, as well as the tendon as a whole, are surrounded in turn by connective tissue. Some tendons are surrounded, in addition, by a sheath that encloses synovial fluid, which acts as a lubricant that reduces friction associated with tendon movements. Tendons include blood vessels and fibroblasts for maintaining tendon tissue, as well as a type of receptor, the Golgi tendon organ (Section 9.4.1) that responds to tension in the tendon.
Inflammatory Responses Acquired Following Environmental Exposures Are Involved in Pathogenesis of Musculoskeletal Pain
Kohlstadt Ingrid, Cintron Kenneth in Metabolic Therapies in Orthopedics, Second Edition, 2018
Musculoskeletal tissues are quite diverse in makeup and physiology. We have seen differences between nucleus pulposus cells, synoviocytes and muscle, for example. Two additional tissues where inflammatory mediators have important effects are tendon and enthesium. These next two sections are devoted to these tissues. Tendon is defined as a “uniaxial connective tissue component of the musculoskeletal system. Tendon is involved in forced transmission between the muscle and bone” [56]. While tendon is not avascular, it is poorly vascularized. It is largely composed of Type I collagen fibrils organized in parallel fashion along the long axis of the tissue. Injury to a tendon involves injury to production and assembly of Type 1 collagen. Tendons establish specific connections between muscles, enthesium and the skeleton by transferring contraction forces from muscle to bone allowing organized body motion. Because of the reduction of blood flow in tendon, it is not surprising that tendon injuries heal slowly; surgery cannot restore a damaged tendon to its normal structural integrity and mechanical strength [57].
Introduction and Review of Biological Background
Luke R. Bucci in Nutrition Applied to Injury Rehabilitation and Sports Medicine, 2020
Tendons and aponeuroses29,32–34 — In general, tendons attach muscle to bone. Tendons are longitudinal and rope-like in shape, while aponeuroses are flat sheets, to connect similarly shaped muscles. Type I collagen bundles are interwoven with a reticular network of Type III fibers, along with blood vessels, lymphatics, and fibroblasts. Attachment to bone is accomplished by a gradual merging of collagen fibers to fibrocartilage to mineralized fibrocartilage to bone. Tendon sheaths cover tendons, allowing for smooth gliding of tendons in their traverses. The ratio of collagen to elastin in tendons is 50:1, which makes tendons very tough and resistant to pulling forces. However, this trait also makes tendon injuries pull apart from bones and muscles.
An Investigation of a Novel Tendon Transfer Surgery for High Median-Ulnar Nerve Palsy in a Chicken Model
Published in Journal of Investigative Surgery, 2019
Geoffrey R. Browning, Anthony H. Le, Jennifer J. Warnock, Ravi Balasubramanian
The medial spur of the left hindlimb was used as a landmark to identify the bifurcation of the EDL tendon. For the implant group chickens, the implant was placed just distal of the EDL tendon bifurcation (mean 8.50 ± 3.73 mm). For the sham group chickens, sutures were placed in a similar location in respect to the EDL tendon bifurcation. The EDL tendon anatomy schematic can be seen in Figure 7 with the depiction of where the implant was located. Anecdotally, the lateral tendon appeared larger than the medial tendon branch, and both tendon branches were subjectively more robust in males than females. Tendon mineralization was suspected in some but not all male chickens just distal to the EDL bifurcation, which was noted by the surgeon's ability to pass the needle through each tendon during placement of sutures. Tendons were surrounded by thin connective tissue. There were no vessels surrounding the bifurcation or proximal EDL branches that required ligation or cauterization.
Cell-cell junctions in developing and adult tendons
Published in Tissue Barriers, 2020
Sophia K. Theodossiou, Jett B. Murray, Nathan R. Schiele
Tendons are musculoskeletal tissues that transfer mechanical forces from muscles to bones and are vital for skeletal movement. A major clinical challenge is the limited healing ability of tendon. If ruptured, tendon healing is characterized by the formation of scar tissue1,2 and inferior mechanical properties, compared to uninjured tissues.3 Even with surgical repair, re-rupture rates range from 3.6% to 94% depending on the tendon, size of the tear, age, and other factors.4–6 In addition, tendon injury rates are climbing, with a 10-fold increase in the incidence of Achilles tendon ruptures from 1979 to 2011.7 The limitations of existing treatment options emphasize the need for tissue engineering and regenerative strategies to improve tendon healing and repair.
Essential role of Mohawk for tenogenic tissue homeostasis including spinal disc and periodontal ligament
Published in Modern Rheumatology, 2018
Ryo Nakamichi, Kensuke Kataoka, Hiroshi Asahara
Currently, musculoskeletal disorders are a major problem that affects healthy life [1]. Within the musculoskeletal system, tendons and ligaments serve as connective tissue. Tendons connect muscles and bones and play an important role in transmitting force, and ligaments connect bone to bone and regulate mobility and stability. Tendons and ligaments function in various parts of the body. For example, the annulus fibrosus connects the vertebral bodies, maintaining stabilization and allowing flexible movement of the spine [2]. The periodontal ligament (PDL) connects the teeth with the alveolar bone and acts not only as a stabilizer but also as a sensory receptor for the masticatory system [3]. Damage to and degeneration of these tissues causes disorders and diseases associated with pain and disability, but the current therapy that relies on self-repair is not sufficient for the reacquisition of mechanical strength [4]. A better understanding of the molecular mechanism of the development and homeostasis of tendons and ligaments is required for the conception of more advanced therapy for these tissues. While research in this area is progressing, it is not as advanced as that in other aspects of the musculoskeletal system.
Related Knowledge Centers
- Bone
- Collagen
- Type I Collagen
- Connective Tissue
- Ligament
- Skeletal Muscle
- Extracellular Matrix
- Fibroblast
- Dense Regular Connective Tissue
- Tendon Cell