An apparatus for cutting a portion of an immobilization cast to facilitate removal of the cast from a body part of a patient may comprise a handle structure for being held by the hand of a user, a cutting device extending from the handle for cutting the cast material, with the cutting device including a blade and a blade movement device configured to cause ultrasonic movement of the blade, and a shielding structure configured for at least partially positioning between the cast and a part of the patient's body part such that a portion of the shield extends between the blade and the body part to shield the body part from the blade.