A handheld medical device comprises an internal flow passage that is in axial alignment with an output drive shaft. The drive shaft is powered by a motor assembly that is offset from the internal flow passage and the output drive shaft. The drive shaft and the motor assembly can be connected by a gear train. A collet mechanism can be used to secure a surgical implement to the handheld medical device. A first button assembly and a second button assembly can be positioned on diametrically opposed portions of the handheld medical device.