Regenerative cells present in adipose tissue are used to treat patients, including patients with musculoskeletal diseases or disorders. Methods of treating patients include processing adipose tissue to deliver a concentrated amount of regenerative cells obtained from the adipose tissue to a patient. The methods may be practiced in a closed system so that the stem cells are not exposed to an external environment prior to being administered to a patient. Accordingly, in a preferred method, regenerative cells present in adipose tissue are placed directly into a recipient along with such additives necessary to promote, engender or support a therapeutic musculoskeletal benefit.