A new application of superelastic SMAs in surgical instruments - hemostatic forceps with safe pressures

Yun Luo 1Masaru Higa Shintaro Amae Tomoyuki Yambe Toshiyuki Takagi 

1. Tohoku University, Sendai, Japan


The authors have proposed a new application of superelastic SMAs in surgical instruments to enhance their safety. The constant stress property exhibited during the stress-induced transition of superelastic SMA is used to control the clamping pressure of hemostatic forceps within a safe range on biological tissues. Conventional hemostatic forcepses have rigid structures and might apply pressure higher than enough on biological tissues. In contrast, with the new SMA combined forceps it is possible to apply sufficient but not excessive pressure for homeostasis or arrest of bleeding, and is therefore able to minimize the damage on tissues under clamping.
In this paper, the basic concept of this new application of superelastic SMAs will be described first. Then design issues including material selection, safe pressure range of general forceps, activation mechanism of induction of transformation by stress will be discussed. Basic designs will be given to match the different purpose and specification of hemostatic forceps. The validity of the proposed concept has been examined by the experimental results obtained from the developed prototypes.


Presentation: oral at E-MRS Fall Meeting 2005, Symposium C, by Yun Luo
See On-line Journal of E-MRS Fall Meeting 2005

Submitted: 2005-05-30 12:32
Revised:   2009-06-07 00:44