Extraction device for bone staples

Inventors

Bianchi, Riccardo • Berberich, Sascha • Siccardi, Francesco

Assignees

Medacta International SA

Abstract

An extraction system for bone staples provided with a first and a second element, comprising a main gripping body having a distal end and a proximal end. The device comprises, in addition, a central rod provided with a proximal end and a distal end, the latter adapted to couple with the first element of the staple. The central rod slides axially within the main gripping body between a first position and a second position by means of suitable movement means. The device has a plurality of abutment elements protruding in the axial direction from the distal end of the main body, which are arranged circumferentially around the central rod, adapted to act on the second element of the staple to obtain, in cooperation with the movement of the central rod, the separation of the second element of the staple from the first element of the staple and the removal thereof.

Core Innovation

The invention provides an extraction system comprising an extraction device and a bone staple, where the bone staple has a first element comprising a plate with a central through hole and four tips, and a second element with a central through hole placed in contact below the plate and enclosed inside a volume defined by the four tips. The extraction device includes a main gripping body with a proximal end and a distal end, and a central rod having a proximal end and a distal end that is adapted to directly couple with the first element of the staple. The central rod is axially slidable within the main gripping body between a first position and a second position.

The extraction device further comprises movement means for moving the central rod and a plurality of abutment elements protruding axially from the distal end of the main gripping body and arranged circumferentially around the central rod. The abutment elements are adapted to act on the second element of the staple to obtain, in cooperation with the movement of the central rod, separation of the second element from the first element and removal of the first element.

In refinement, a lever-to-translation conversion is implemented in which movement of a first lever actuator through a rack-and-pinion mechanism drives axial translation of the central rod. The rod travel is defined with a first position, a second position, and a third intermediate position between the first and second positions, and the distal end of the central rod includes an edge configured to engage a centrally formed undercut on the bone staple below the first element.

Geometric constraints are further specified at the third intermediate position, and an elastic spring-back element can be included to act between the central rod and an internal portion of the distal end of the main gripping body.

Claims Coverage

The document includes one independent claim directed to a bone staple extraction system, with dependent claims that add specific structural and positional refinements to the central rod actuation, engagement geometry, and rod travel positions. Across the independent claim, the inventive concept is centered on directly coupling the central rod to the staple first element and using circumferential abutment elements acting on the second element to achieve separation and removal.

The claim set is directed to a bone staple extraction system where a central rod directly couples to the staple first element and is moved axially between positions while circumferential abutment elements act on the second element to separate and remove the first element. Dependent refinements specify rack-and-pinion lever-to-translation conversion, engagement of a centrally formed undercut using a distal edge, controlled geometry at a third intermediate rod position, and optional use of an elastic spring-back element.

Stated Advantages

Documented Applications