Yumoto Orthopaedic Clinic (JP HOME) is the Originator of
  Percutaneous Trigger Finger Release Surgery with Guided Knife		 Since
2011/07/31		  
Shape and Function

- Guided Knife -

Guided Knife - Shape -

[Appearance and terms]
1) The knife consists of four parts, welded together as a piece.
  • They are grip section, shaft section, blade section and guide section respectively.
2) Guided Knife comes in two types with different blade section.
  • Standard: Guided Knife with sharp blade.
  • Blunt: Guided Knife with blunt blade.
When simply talking about Guided Knife, it refers to one with sharp blade.

3) This instrument is NOT disposable, and could be reused by washing and sterilization.



[Blade Section]
(Comments from the inventor)
Right figure demonstrates two types of Guided Knives, and part names are the same.

During the guided division as in the upper illustration, K is the functional part of Blade section.

You may have witnessed in my operation videos already that H sometimes projects from the epidermal surface during and around guided division.

This drawing is from my patent application documents.
Blade section consists of three parts, H,J and K. These are imaginary divisions and there are no actual marks between them.
"H": Part of blade section that rises above the epidermal surface as in the drawings above. H varies in individual cases.
"K": Functional part in A1 pulley division from point "a" until "b" in the same drawings.
"J and H": Functional part at Tip-up division of A1 pulley.

Guided Knife - Function -

[Division of A1 Pulley]
Guided Knife can divide A1 Pulley without injuring the flexor tendon underneath, once its guide section has been set between.


Guided Division again is a term I assigned to explain GK-PTFR procedure, and essential technique for GK-PTFR.

Fig.2. is a modified reproduction from my contribution to the book below. When A1 pulley has been divided halfway like this, the consequence is very easy to predict because of the role of guide section.

In GK-PTFR, passage of the division of A1 pulley could easily be foreseen if it had started from the right place, due to the role of guide section, hence the term guided division.

Generally speaking, as percutaneous trigger finger releases are closed operations, it is very encouraging that final achievement comes as a natural consequence and not dependent on good luck in GK-PTFR.

"Trigger Finger Operation by Guided Knife", p.2-9. Yoshiji Yumoto

Guided Knife Specifications

[Where to buy]
Y's Guided Knife can be purchased at Tsuda Medical Instruments Co., and reached at:

Tsuda Medical Instruments Co.
Zip: 933-0958
46-3 Namioka, Takaoka City, Toyama Prefecture
Tel: 0766-23-3625
FAX: 0766-23-3679

Due to restriction by Pharmaceutical Affairs Act and patent reasons, this medical instrument could not be shipped out of Japan (as of July 1, 2011).

Yumoto ORTHO CLINIC is not a dealer of any medical instrument, and owes no responsibility to any damages derived from use or handling of Y's Guided Knife or from other medical instruments thereof.

[Intended use of Guided Knife]
Aside from PTFR, Guided Knife has realized minimally invasive surgery for each of the following disabilities.
They are linked with each individual video in the VideoLibrary.

1) de Quervain disease, to divide 1st dorsal compartment.
2) Carpal tunnel syndrome,, to divide transverse carpal ligament.

[U.S. Patent]
US Pat No.5,893,861 (PDF)

[Japanese Patent]
･ 1852829 (PDF)

[EU Patent]
･ Peritenon Incision Knife (PDF)
･ Surgical knife for cutting out tendon sheath
･ EU Patent Office