A device for treating de Quervain's tenosynovitis may include a handle, an introducer shaft extending from the handle, and a blade that includes a blade shaft extending along a top surface of the introducer shaft and onto the handle and a blade cutting edge that faces toward the handle. The device may further include a blade slider attached to a proximal portion of the blade shaft, a blade pivot attached to at least one of the proximal portion of the blade shaft or the blade slider, an upper deck along which the blade slider slides in an upper horizontal orientation, and a lower deck along which the blade slider slides in a lower horizontal orientation. The blade pivot is configured to allow the blade slider to rotate in a plane that is perpendicular to a plane of the introducer shaft.