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.

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.

An electronic knife assembly and associated systems and methods are disclosed herein. In some embodiments, the knife includes a blade and a handle operably couplable to the blade. The handle can include an oscillator operably coupled to the blade, at least one sensor configured to obtain one or more measurements, and a controller operably coupled to the oscillator and the least one sensor. The measurements from the sensor can include a spatial position of the electronic knife, a spatial orientation of the electronic knife, a mass of a user's hand, a grip of the user's hand, and/or a resistance to the oscillation of the blade. The controller can adjust an operating frequency of the oscillator based at least partially on the one or more measurements from the at least one sensor. The handle can also include a wireless power supply.