Patent ID: 8246642

Claim:
An ultrasonic medical instrument comprising a handpiece and medical ultrasonic blade assembly, wherein the handpiece and medical ultrasonic blade assembly includes: a) a vibration antinode; b) a handpiece; and c) a medical ultrasonic blade, wherein the medical ultrasonic blade includes a first connecting member having a longitudinal axis, wherein the handpiece includes a second connecting member which is substantially coaxially aligned with the longitudinal axis and which has a distal portion which is in non-threadable and ultrasound-transmitting direct physical contact with a proximal portion of the first connecting member proximate the vibration antinode, wherein the handpiece includes a third connecting member which surrounds and is rotatably or fixedly attached to the second connecting member and which is threadably engaged with the first connecting member proximate the vibration antinode, and wherein the third connecting member is attached to the second connecting member when the medical ultrasonic blade is attached to the handpiece and the medical ultrasonic blade can be completely removed from the handpiece without removing the third connecting member from the second connecting member.