IASTM stands for Instrument Assisted Soft Tissue Mobilization, and has come to mean any type of tool-assisted massage. Sometimes it goes by the shortened name of ISTM, or by particular brands of IASTM such as Graston® and Fibroblaster. Westernized Gua Sha has often been called an IASTM as well. Consistent with other IASTMs, Gua Sha considers certain trauma to the tissues desirable and leaves patients with a “road-rash” effect immediately after treatment. The main focus of IASTM is the direct, mechanical breaking up of tissue. These tooled massages are generally unresearched and are usually quite aggressive. They vary in how they are done, whether they have positive effect, and how many negative side effects they can have. A big concern with IASTM is the damage it can cause to healthy tissue.