A retractor system for percutaneous surgery in a patient includes first and second retractor portions positionable opposite one another in an incision of the patient. The system also includes at least one actuating member operable to provide an oscillating motion to at least one of the first and second retractor portions. The actuating member is in communication with a controller and is responsive to the controller to move and adjust at least one of the first and second retractor portions between a first position and a second position. The system also includes at least one pressure sensor and display and at least one timing circuit with display. In another form, a method is directed to retracting tissue for percutaneous access to a surgical site in a patient using the pressure sensors and display as will as the timing circuit and display to assure that the amount of pressure applied and the duration does not exceed pre-determined values.
