A retractor instrument for minimally invasive surgery may include a housing with a longitudinal axis, an arm extending from a distal end of the housing, and an actuation mechanism, wherein actuation of the actuation mechanism causes radial expansion of the arm relative to the longitudinal axis. The device may be adapted for use with an endoscope or arthroscope or may be an integral part of one such scope. A method of performing surgery in constrained areas within the body is also included and may be applicable to the carpal tunnel of a wrist and palm or the cubital tunnel of an elbow.