Connective tissue is a broad term referring to different supportive tissue types within the musculoskeletal system. All connective tissues consist of a main ground substance (matrix), a set of protein fibers, and a community of cells living among the fibers. Variations are based on thickness of the matrix, density of fiber content, and types of cells present.
Loose connective tissues include adipose (fat) and muscle coatings. Dense connective tissues contain more collagen fibers and include tendons and ligaments. Cartilage has a rubberized form of the gel matrix and an even higher density of fibers. Bone is the most dense connective tissue with a calcified matrix. The protein fibers are interwoven throughout all the connective tissues, so anything that affects the tissue anywhere translates throughout the body.