WO2014123874A1

WO2014123874A1 - System for performing surgical procedures with a tool tube that is bent to provide a view of the tissue working member at the end of the tube

Info

Publication number: WO2014123874A1
Application number: PCT/US2014/014627
Authority: WO
Inventors: Zachary A. KEMP; Matteo Gubellini
Original assignee: Stryker Corporation
Priority date: 2013-02-05
Filing date: 2014-02-04
Publication date: 2014-08-14

Abstract

A system (30) for performing minimal invasive procedures wherein the site at which the procedure is performed is accessed through an access tube (32) that is part of the system. The system includes a tool tube (78) that is inserted in the access tube. A tissue working member (120) that component that performs the procedure, is disposed at the distal end of the tool tube. Slightly rearward of the distal end of the tool tube the tube is bent so as to define a tube main section (82) and tube distal section (84). The bend (83) facilitates the view of the tissue working member.

Description

SYSTEM FOR PERFORMING SURGICAL PROCEDURES WITH A TOOL TUBE THAT IS BENT TO PROVIDE A VIEW OF THE TISSUE WORKING MEMBER

AT THE END OF THE TUBE

Field Of The Invention

[0001] This invention generally relates to a tool system for performing a minimally invasive surgical procedure.

More particularly, the tool system of this invention is designed to reduce obstructions in the practitioner' s view of the site to which the tool is applied.

Background Of The Invention

[0002] A surgical procedure typically involves making incisions into the epidural layer, the skin, of the patient and sometimes the bone to access the tissue on which the procedure is to be performed. The need to having to

separate this soft tissue and hard tissue, and then reattach the cut tissue, exposes the patient to appreciable trauma. In some instances, post procedure, the patient requires more time to recover or is subjected to more discomfort as result of the healing of the tissue that is cut to access the surgical site than as a result of the healing that goes on due to the procedure performed at the surgical site.

Further, if it is necessary to form a large incision in a patient to access the surgical site, an appreciable surface area of the patient's internal tissue is exposed to the ambient environment. Even in the most sterile of operating environments, this means that the patient's internal tissue is exposed to agents that could infect the tissue. Should the tissue become infected, the patient may be subjected to additional discomfort and the recovery delayed.

[0003] Consequently, it is a goal of modern surgical practice to minimize, if not eliminate, the need to make incisions into a patient to access the site internal to the body at which the procedure is to be formed. Generally, the practice of performing a procedure on a patient in which either no incision is made to access the surgical site or only a small incision is made is known as a minimally invasive surgical (MIS) procedure.

[0004] To perform some MIS procedures, a small incision is cut in a patient. An access tube is inserted in the incision and directed toward the site at which the procedure is to be performed. An access tube typically has an inside diameter of between 1.0 and 4.0 cm and, more often, between 1.4 and 3.0 cm. Surgical instruments especially designed to perform an MIS procedure are then inserted into the access tube to perform the procedure. These instruments differ from many surgical instruments in that they are formed with tubes or necks that are relatively long in length, (lengths of 9 cm or more) and are narrow in width, (diameters of less than 0.6 cm) . These instruments have this structure so they can fit in the access tube and extend to the tissue at which the procedure is to be performed. At the distal end of the instrument is a working component, the component of the instrument that is applied to the tissue to perform the procedure. The tool often includes an elongated tube.

Internal to this tube are one or more linkage members that control the operation of the component. For example, if the component is a rotating head, such as a bur, the linkage is a rotating shaft. The shaft transfers the rotational motion of the motor connected to the tool to the head so that the head will rotation. If the working component is the jaw of a pair of scissors or a clamp, the component internal to the shaft is a cable. The cable is attached to mechanism that allows the surgeon to longitudinally move the cable in the shaft. The displacement of the cable results in the

appropriate motion of the working component that extends from the shaft. [0005] Some surgical tools used to perform MIS procedures are components of surgical tool systems. One component of this system may be the handpiece. The handpiece contains a power generating unit. This power generating unit converts one form of energy into another form of energy useful for performing the desired procedure. For example, some

handpieces include a motor. The motor is a power generating unit that converts electrical energy into mechanical energy. A laser converts electrical energy into photonic (light energy) . A front end attachment is removably attached to the handpiece. The front end attachment is the component of the system that has the elongated shaft. In some surgical tool systems, the working component is an integral part of the front end attachment. In still other surgical tool systems, the working component is removably attached to the attachment. For example if the working component is a rotating tool such as a drill bit, a rasp, a bur or a shaver. The rotating component may be removably fitted to the attachment. This type of working component has an elongated shaft. The elongated shaft of the working

component is often dimensioned to be removably seated in the tube of the front end attachment. A coupling assembly integral with the attachment may removably connect the shaft of the rotating component to the shaft of the motor integral with the handpiece.

[0006] It is known to provide a tool system designed for an MIS procedure with a tube that, adjacent the proximal end, is formed with a bend or an angle. This is so, when the surgeon places the tool tube in the access tube to perform the procedure, the proximal portion of the tool is laterally spaced from the tool. When the surgeon is

manipulating the tool, the proximal portion of the tool as well as the hand manipulating the tool are spaced away from the line of site down the tube in which the tool is seated. This minimizes the extent to which the proximal portion of the tool, as well as the hand of the surgeon manipulating the tool, obstruct the view down the tube.

[0007] The above design feature reduces the obstructions in the surgeon's line of sight when performing an MIS procedure. However, a disadvantage of the current system is that it is that it tool tube often obstructs the downline view of the tissue working component. The obstruction of this view can make it difficult for the surgeon to

manipulate the tool to ensure that the working component is correctly applied.

[0008] One solution to minimizing the extent the view of the tissue working component is obstructed is to form the tool tube with a curve adjacent the distal end of the tool. The tissue working component extends forward of this curve. A disadvantage of this solution is that the curved distal end of the tube is difficult to maneuver in the relatively confines of the access tube.

[0009] Another disadvantage of these assemblies is that, to ensure that the rotating shaft internal to the fixed outer tube can rotate, a liner formed from low friction material is disposed in the fixed in the tube that forms the front end attachment. This liner forms the interface between the rotating shaft of the bur and the fixed

attachment. This is a disadvantage because, is that, each time this type of curved tube-and-bur assembly is used, the liner is subjected to significant wear. It is not uncommon for the liner to wear out after it has been used for just a single procedure or a part of a procedure. It is difficult, if not practically impossible, to change the liner each time a new bur is required. This is especially true if one is to try to change the liner in the middle of a surgical

procedure. Accordingly, this type of curved tube-and-bur assembly is typically configured as a use once item. In comparison to providing a system that comprises a single front end attachment to which separate burs can be

successively removably attached, it is more costly to provide a system wherein each time this assembly is

required, a new tool-and-bur assembly must be used.

Summary Of The Invention.

[00010] This invention is directed to a new and useful surgical tool sometimes referred to as a surgical tool system. The surgical tool system of this invention is designed to perform a minimally invasive surgical procedure. The surgical tool system of this invention includes

components designed to present the surgeon with a view of the system working component that is relatively

unobstructed .

[00011] The tool system of this invention includes an access tube. The tube is shaped to be inserted into a patient and directed to the site internal to the patient at which the procedure is to be performed. The tube defines a channel in which other components of the system can be inserted and positioned at the surgical site.

[00012] Another component of the tool of this system is a tool tube, sometimes referred to as the front end

attachment. The working component, the component of the system that actually performs the surgical or therapeutic task on the patient extends forward from the distal end of the tool tube. System components that actuate the working component extend from the proximal end of the tool tube. The tool tube itself has three sections. There is a

proximal section, the section to which the system components that actuate the working components are attached. A main section extends forward from the proximal section. The longitudinal axis of the main section is angularly offset from the longitudinal axis of the proximal section. A distal section extends forward from the main section so as to form the third section of the tool tube. The distal section is the section from which the working component is attached. The longitudinal axis of the distal section is axially offset from the longitudinal axis of the main section. In some but not all versions of the invention the longitudinal axes of the proximal and distal sections are parallel. Typically the main section is longest of the three sections. In some but not all versions of the

invention, the overall length of the main section is greater than the combined lengths of the proximal and distal

sections. In an alternative two section version of the tool tube of this invention, the proximal section is not present.

[00013] In many but not all versions of the invention, the tube sections are of different diameters. Typically, the proximal section has the largest diameter. The distal section has the smallest diameter. In many but not all versions of the invention, the system is further designed so working member extends outwardly beyond the perimeter of the cross sectional area subtended by the distal section.

[00014] When the tool system of this invention is used, the access tube is inserted in the patient so as to open above the tissue internal to the patient at which the procedure is to be performed. The tool tube, with tissue working component attached thereto, is inserted in the access tube. A handpiece may be coupled to the proximal end of the tool. The surgeon holds the handpiece to direct the working component to the site at which the procedure is to be performed. Owing to the bend between the proximal and main sections of the tool the proximal end of the tool tube and attached handpiece are angled out of the way of the open proximal end of the tube. These components of the system thus only minimally, if at all, obstruct the view of the surgeon into the tube. Owing to the angle between the main section and distal end of the tube, the working component is laterally offset from the longitudinal axis down the main section of the tube. Owing to this lateral offset, the main section of the tube does not appreciably obstruct the surgeon' s view of where the application of the working component against the tissue to which the component is being applied. This is especially true in constructions of the invention wherein the working component extends beyond the perimeter of the distal section.

[00015] The surgical tool system of this invention

includes features that facilitate the removable attachment of the tissue working member to the tool tube. Thus

multiple tissue working members can be successively be used as part of the tool system of this invention.

Brief Description Of The Drawings

[00016] The invention is pointed out with particularity in the claims. The above and further features and benefits of this invention are understood by the accompanying Detailed Description in combination with the drawings in which:

[00017] Figure 1 is an overview of the components of a surgical tool system of this invention;

[00018] Figure 2 is a cross sectional view of the interior of the front end attachment without any components disposed in the tool;

[00019] Figure 3 is a cross sectional view of the interior of the front end attachment with the components internal to the tool;

[00020] Figure 3A is an enlarged cross sectional view of a portion of the interior of front end attachment;

[00021] Figure 4 is a plan view of one working component that can be employed as part of the tool system of this invention ; [00022] Figure 5 is a cross sectional view of the front end attachment with the working component mounted to the attachment ;

[00023] Figure 6 is a side view of the front end

attachment and tissue working component seated in the access tube; and

[00024] Figure 7 is a view looking forward into an access tube showing how it is possible to view the tissue working component located adjacent the distal end of the tube.

Detailed Description

[00025] As seen in Figure 1 a surgical tool system 30 of this invention includes an access tube 32. Access tube 32 is inserted into the patient to define an access

channel (33) (Figure 7) internal to the patient to the tissue on which the procedure is to be performed. The system includes a working component 120, the head of which is seen in Figure 1. The working component 120 is the component of the system that is applied to the tissue to performed the desired procedure. Proximal to the working component 120 is a handpiece 50. ("Proximal" is understood to mean toward the surgeon holding the handpiece 50; away from the site to which the working component 120 is applied. "Distal" is understood to mean away from the surgeon, toward the site to which the working component 120 is applied.) A tool tube 78 extends forward from the handpiece to connect the working component 120 to the handpiece 50. Sometimes a number of other components are attached to the tube. One such component may be a foot 62 that facilitates the

removable attachment of the tool tube 78 to the

handpiece 50. In these versions of the invention that tool tube 78 and attached components may be collectively

described as a front end attachment 60. [00026] Access tube 32 is generally cylindrical in shape. The depicted tube is shown as having a lip 34 that extends outwardly around the outer perimeter of the distal end of the tube. A finger hold 36 extends radially away from a section of the lip 34.

[00027] The structure of the handpiece 50 is a function of the structure and purpose of the working component 120. For example, in the illustrated version of the invention, the working component 120 is bur head. The bur head functions by rotating against tissue. In these versions of the invention, internal to the handpiece is a motor 52,

represented as a dashed rectangle. Not depicted is the shaft of the motor 52. In other versions of the invention internal to the handpiece is a power generating unit that converts electrical energy into another form of energy, such as photonic energy. Alternatively, in some versions of the invention the handpiece the handpiece may simply function as a passive handpiece. The primary function of the handpiece of this version of the invention is to serve a handhold the surgeon manipulates to apply the tissue working

component 120 to the surgical site. In still other versions of the invention, the handpiece may consist of one or more fingerholds. If there are plural fingerholds often one fingerhold is able to move relative to the other fingerhold. This movement drives a manually actuated tissue working component 120.

[00028] In many versions of the invention, the tool tube 78, especially if part of a front end attachment 60, is removably attached to the handpiece 50. In Figure 1, an adapter 57 is shown immediately forward of the handpiece 50. Adapter 57 is designed to be removably attached to the front end of the handpiece 50. Ring 53 integral with the

handpiece represents the coupling assembly integral with the handpiece that removably holds adapter 57 to the handpiece 50.

[00029] Adapter 57 contains coupling assemblies that

(1) removably hold the front end attachment to the

adapter 57 and (2) removably connect the drive member integral with the tissue working member 120 to the handpiece drive components. In this version of the invention, adapter 57 connects the foot 126 (Figure 4) integral with the tissue working component 120 to the shaft integral with the handpiece motor 52. Ring 58 represents the coupling assembly integral with the adapter 57 that removably holds the front end attachment 60 to the adapter. The structure of the adapter, when present, is a function of the structure of the handpiece that is a part of this system.

Accordingly, it should be understood that the structure of the adapter is not part of the present invention.

[00030] The structure of front end attachment 60 including the tool tube 78 integral with the attachment is now

described by reference to Figures 2 and 3. Attachment 60 includes a proximal end foot 62 that, in the planes

perpendicular to the longitudinal axis of the foot is circular in cross section. The outer diameter of the foot changes along the length of the foot. Generally the outer diameter of the foot 62 around the longitudinal axis decreases with increases in distance from the proximal end of the foot. While not called out in the Figures, in the illustrated version of the invention, there is a section distal to the proximal end of the foot wherein the outer diameter of the foot is constant.

[00031] Foot 62 is formed to have a number of bores.

Bore 64 extends forward from the proximal end of the foot. Bore 66 is smaller in diameter than bore 64 and extends forward from bore 64. (Undercut between bores 64 and 66 not identified.) A bore 68 extends forward from bore 66 and is smaller in diameter than bore 66. Bores 64, 66 and 68 are designed to receive the proximal portions of adapter 57. Not identified a geometric features adjacent the bores 64, 66, 68 that cooperate with the attachment-to-adapter

coupling assembly for removably holding the attachment 60 to the adapter 57.

[00032] A bore 72 extends proximally rearward from the distal front end of attachment foot 62. Bore 72 is smaller in diameter than bore 68. A small through hole 70 extends through the web internal to foot 62 that forms the proximal end base of bore 68 and the distal end base of bore 72.

Hole 70 is smaller in cross sectional diameter than both bore 68 and bore 72.

[00033] Tool tube 78 is in the form of an elongated tube through which a lumen 79 extends proximally to distally along the length of the tube. Tube 78 has outer and inner diameters that generally, along the length of the tube are constant. In some versions of the invention, tool tube 78 has an outer diameter that is a maximum of 0.8 cm. In still other versions of the invention, tool tube 78 has a diameter of 0.6 cm or less. In still other versions of the

invention, tool tube 78 has an outer diameter of 0.4 cm or smaller. The tool tube 78 has a wall thickness of between 0.02 and 0.1 cm. Tool tube 78 has a proximal section, section 80, a main section, section, section 82, and a distal section, section 84. The longitudinal axes of the adjacent sections are angularly offset from each other. In some versions of the invention, the longitudinal axes of the proximal and main sections 80 and 82, respectively, are offset by an angle of 4 to 14°. In still other versions of the invention sections 80 and 82 are offset by an angle of between 7 to 11°.

[00034] The longitudinal axes of the main and distal sections 82 and 84, respectively, are offset by an angle that is within the above-stated ranges of offset angles between the proximal and main section, 80 and 82,

respectively. In some, but not all versions of the

invention, the two offset angles of the two pairs of

adjacent tool sections are identical to each other. In these versions the longitudinal axis of the tool distal section 84 is parallel to and spaced from the longitudinal axis of the tool proximal section 80.

[00035] Further it should be understood that the bend at least between the main section 82 and distal section 84 visually appears as a bend 83, not a curve. In quantifiable terms, this bend has a maximum radius of curvature of 15 cm. In more preferred versions of the invention, the maximum radius of curvature is 12 cm. While not required, the bend 81 between the tool proximal section 80 and main section 82 typically has a similar, if not identical

relatively small radius of curvature.

[00036] It sure further be understood that, in preferred versions of the invention, tool tube 78 is constructed so that the longitudinal axes of tube sections 80, 82 and 84 are in a common plane.

[00037] Generally, tool tube 78 is designed so that the main section 82 and distal section 84 collectively have a length greater than the length of the access tube 32. In some versions of the invention, tube 78 proximal section 80 has a length of between 2 and 5 cm. The proximal most portion of tube proximal section 80 is seated in bore 72 internal to foot 62. When attachment 60 is assembled, the portion of the proximal section 80 that extends forward of foot 62 is anywhere from nonexistent, 0 cm in length, to 1 cm. Tool main section 82 has a length of between 3 and 15 cm. Tool distal section 84, including the below

described nose 88, has a length of less than 5 cm and typically between 1 and 5 cm. [00038] Tool tube 78 is further formed to have forward of distal section 84 a nose 88. Nose 88 is conical in shape. A bore 90 extends longitudinally through nose 88. Bore 90 extends from the distal end of nose 88 into the central lumen that extends through the tool.

[00039] Internal to tool tube 78 are six bearing

assemblies. The bearing assemblies center the elongated drive member associated with the tissue working

component 120 in the tool. The bearing assemblies also allow the elongated drive member to move within the tool tube 78 so the drive member can, as appropriate, actuate the tissue working member 120. In the depicted version of the invention, the elongated drive member associated with the tissue working member is a rotating shaft, shaft 124

(Figure 4 ) .

[00040] Figure 3A is an enlarged view of one bearing assembly, the below discussed bearing assembly 96. As evidenced by this drawing, each bearing assembly consists of a ring like outer and inner races 130 and 136. Outer race 130 has an outer diameter that facilitates the close slip fitting of the bearing assembly 96 in the tool. The inner race 136 is configured to allow the close slip fit of the bur shaft 124 in the race 136. Ball bearings 134 between the races 130 and 36 allow the inner race 136 to rotate freely relative to the inner race. The other bearing assemblies 90, 92, 94, 98 and 100 are of similar, if not identical, construction.

[00041] One bearing assembly, assembly 90, is located in the portion of the tool proximal section that is seated in foot bore 72. A spacer, not identified, holds bearing assembly 90 in position forward from the proximal end of the tool tube 78. A second bearing assembly, assembly 92, is spaced approximately 0.5 cm forward of bearing assembly 90. A helical spring 91 is disposed between bearing assemblies 90 and 92. A third bearing assembly, assembly 94, is located in the tube main section 82. In most versions of the invention, bearing assemblies 92 and 94 are spaced equidistantly from the center of the bend between the tube proximal and main sections 80 and 82, respectively. Ideally this distance, the distance from the bend to the bearing assembly, is at least 1.0 cm from the bend and more

typically approximately 1.5 cm from the bend to the bearing assembly .

[00042] A fourth bearing assembly, bearing assembly 96 is located in the tool main section a short distance from the bend that separates tool main section 82 from tool distal section 84. A fifth bearing assembly, assembly 98, is located in the tool distal section 84. In many versions of the invention, bearing assemblies 96 and 98 are spaced equidistantly from the center of the bend between the tube main and distal sections 82 and 84, respectively.

Typically the bend-to-bearing distance in this portion of tool tube 78 is the same as the bend-to-bearing distance adjacent the bend between the proximal and distal sections 80 and 82 of the tool tube 78. A sixth bearing assembly, bearing assembly 100, abuts the step internal to the tool that forms the concealed proximally directed face of nose 88. Bearing assembly 100 is located approximately 0.5 cm forward of bearing assembly 98. A helical spring 99 is disposed between the outer race of bearing assembly 98 and the outer race of bearing assembly 100.

[00043] Springs 91 and 99 are present to adjust for component tolerances and variations that occur during the manufacture of the front end attachment 60.

[00044] Also internal to attachment tool tube 78 are three sleeves 102, 104 and 106. The sleeves are formed from stainless steel. Sleeves 102 and 104 and 106 are each seated immediately forward of bearing assemblies 92, 94 and 96, respectively. Each sleeve 102, 104, 106 is formed with a bore that is conic is shape. More particularly each sleeve is arranged so that the wide end of the sleeve bore is distally forward of the bearing assembly with which the sleeve is associated. The narrow diameter proximal end of the sleeve bore is immediately adjacent the opening that extends axially through the associated bearing assembly 92, 94 or 96.

[00045] A set of tube-shaped spacers, seen only in

Figures 3 and 3A, hold the bearing assemblies 90, 92, 94, 96, 98 and 100 and sleeves 102, 104 and 106 in their proper positions in tube lumen 79. In some versions of the

invention, a first spacer, spacer 110 extends from the proximal end of the tube to the proximally directed face of bearing assembly 90. A spacer 112 extends from the distally directed face of sleeve 102 and the proximally directed face of the outer race of bearing assembly 94. A spacer 114 extends between the exposed face of spacer 104 and the facing outer race face of bearing assembly 96. A spacer 116 extends between the sleeve 106 and bearing assembly 98.

Spacers 110 and 114 have a wall thickness of between 0.01 and 0.1 cm. As discussed below, in one method of assembling attachment 62 of this invention, spaces 112 and 116 are bent. These spacers 112 and 116 have a wall thickness of between 0.01 and 0.02 cm.

[00046] One means of assembling front end attachment of this invention is to provide a straight tube that has the desired dimensions of the tool tube. The nose 88 is added to the formed with this tube. Bearing assemblies 90, 92, 94, 96, 98, 100, springs 91 and 99, sleeves 102, 104 and 106 and spacers 110, 112, 114 and 116 are stacked in the

appropriate order in the tube. The tube is then bent to form tool tube 78. More particularly, the bending forms the bends between the tube proximal 80 and main section 82 and 82 and between the main section 82 and the distal section 84. As a consequence of this bending bends are formed in spacers 112 and 116.

[00047] Tool tube 78 with the components contained therein is then press fitted in bore 72 internal to front end attachment foot 62. In some versions of the invention, spacer 110 seats on the annular washer-like web internal to the foot that defines both the distal end of bore 68, hole 70 and the proximal end base of bore 72.

[00048] In the depicted version of the invention, working component 120, now described with respect to Figure 4, is a bur head. The bur head shown is bulbous in shape. In the illustrated version of the invention the bur head is, more particularly spherical in shape thought that is understood to not be limiting as to this invention. While not

illustrated, it is understood that tissue cutting features flutes extend outwardly from the bur head. These tissue cutting features may be flutes or grains of hard particles such as real or artificially formed diamond grains. A cylindrical stem 122 extends distally away from the bur head. The stem 122 typically has a diameter of 0.2 cm or less and more often a diameter of 0.15 cm or less. A cylindrical flexible shaft 124 extends distally away from stem 122. Shaft 124 is distinguishable from stem 122 in that the diameter of the shaft 124 is less than that of the stem. Shaft 124 typically has a diameter of 0.15 cm or less and more often a diameter of 0.12 cm or less.

[00049] A foot 126 extends distally rearward from

shaft 124. In the depicted version of the invention, foot is a cylindrical in shape and has a diameter less than that of shaft 124. The foot 126 has a diameter usually less than 0.12 cm and more often less than 0.1 cm. Foot 126 is present in the described version of the invention because adapter 57 and shaft 124 are collectively designed to allow the practitioner to adjust the extent to which the tissue working member 120 extends forward of attachment nose 88. Foot 126 serves to limit the range of distance that the tissue working member can be adjusted. Specifically, the presence of foot 126 prevents the practitioner from

configuring the system so the tissue working member can seat and rotate against nose 88. This contact, if it allowed to occur, would result in excessive wear of the components as well as result in undesirable friction heating. Further the presence of the foot limits the extent to which the tissue working member can be positioned forward of the nose. If the tissue working member is positioned to forward of the nose the exposed stem 122 or shaft section may be subject to flexure that could result in component failure.

[00050] In some versions of the invention, the tissue working component, 120, stem 122, shaft 124 and foot 126 are formed from a single piece of material. Often these

components are made from a single piece of stainless or tool steel .

[00051] System 30 of this invention is prepared for use by first fitting adapter 57 to the handpiece 50. Front end attachment 60 is fitted to adapter 57. If necessary the handpiece 50 is connected to a console (not illustrated) . The console supplies the power that energizes the power generating unit (motor 52) internal to the handpiece. The tissue working component 120 is fitted to the handpiece 50. More particularly foot, 126, shaft 124 and stem 122 are inserted into tool tube lumen 79 through bore 90. As the foot 126 moves proximally through the tool, the foot enters the conical bores associated with first sleeve 106, then sleeve 104 and then sleeve 102. The passage of the foot through the sleeve bores centers the foot and then shaft 124 within bearing assemblies 90, 92, 94, 96, 98 and 100. Once the tissue working member 120 is fitted in tool tube 78 it should be appreciated that stem 122 is seated within bearing assembly 98 as seen in Figure 5. In the described version of the invention, adapter 57 provides the connection between the output shaft integral with the handpiece motor 52 and shaft 124 integral with the tissue working member 120.

[00052] As partially seen in Figure 5, as a consequence of tissue working member shaft 124 being seated in the bearing assemblies, the shaft 124 develops two curves within

tube 78. A first curve is formed in the section of the shaft that extends between bearing assemblies 92 and 94. This curve can be considered to be defined by a section of circle that is defined by the locations of bearing

assemblies 92 and 94, a tangent line defined by the line through bearing assemblies 90 and 92 and a tangent line through bearing assemblies 94 and 96. This assumes that bearing assemblies 92 and 94 are equally spaced from the bend between the tube proximal and distal sections 80 and 82, respectively. The second curve is formed in the sections of the shaft 124 that extend between bearing assemblies 96 and 98. This curve extends along a section of circle defined by bearing assemblies 96 and 98, the tangent line of the circle defined by the line extend through bearing assemblies 94 and 96 and the tangent line of the circle defined by the tangent line extending through bearing assemblies 98 and 100.

[00053] The foot 62 of the front end attachment 60 is connected to adapter 57. Adapter 57 holds the attachment and tissue working member to the handpiece 50. The adapter also connect the foot 126 integral with the tissue working member 120 to the output shaft of the handpiece motor 52.

[00054] In versions of the invention wherein the bearing assemblies that define the opposed terminuses of the curve of the shaft 124 are equally spaced from the bend, the shaft curve has a radius of curvature not less than the radius of curvature of the bend of the tool tube. It should further be understood that the components of this invention are further configured so that shaft 124 does not rub against the adjacent tube spacer.

[00055] At the start of the procedure, the practitioner inserts the access tube 32 into the patient so that the distal end of the tube is directed towards the location internal to the patient at which the procedure is to be performed. This process may involve cutting one or more incisions in the patient and/or retracting tissue so a path can be cleared for the insertion of the access tube.

[00056] The practitioner then inserts the tissue working component 120 in the access tube 32 so the component can be applied to the tissue on which the procedure is to be formed as seen in Figure 6.

[00057] As discussed above, the longitudinal axis of tool distal section 84 is angularly offset from tool main

section 82. Consequently, as seen in Figure 7 this means that, when one looks down the access cannula the distal section 84 is laterally spaced away from the main

section 82. By extension, this means that the tissue working component 120, which extends forward from the tool distal section 84, is likewise spaced from the main

section 82. As seen in Figure 7 this reduces the extent to which tool tube 78 blocks the view of the application of the tissue working component 120 to the tissue to which the component is applied. This is especially true in

configurations of this invention wherein portions of the tissue working component extend outwardly beyond the cross- sectional area subtended by tool distal section 84.

[00058] Thus, in comparison to other systems used to apply a tissue working component in a minimally invasive process, the system of this invention only presents an obstruction of relatively small area between the tissue working component 120 and the practitioner performing the procedure. This makes it possible for the practitioner, with relative ease, view the application of the tissue working

component 120 to the tissue to which the component is applied. Providing the surgeon with this ability to easily view the tissue working component 120, makes it possible for the surgeon to improve the overall efficiency with which the procedure is performed.

[00059] When the tissue working invention includes the rotating shaft 124 of the described version of the

invention, the shaft rotates around the arc around which the shaft normally extends. Owing to the relatively wide radius of curvature of this arc, the rotation of the shaft around this arc does not impose appreciable mechanical stress on the shaft 124. This means the stress of the rotation of this shaft typically is not sufficient to cause breakage of the shaft.

[00060] Still another feature of system 30 of this

invention is that the components forming front end

attachment 60 are capable of withstanding the rigors of autoclave sterilization. Once the system is used in a procedure, the tissue working component 120 is removed from the handpiece and front end attachment. Since the tissue working component is the component of the system that is least likely to be able to be reconditioned, this component can, if necessary, be discarded. The handpiece and, more significantly, the front end attachment can then be

decontaminated and sterilized. Once these components of the system are decontaminated and sterilized, a new tissue working component can be fitted to the attachment and the handpiece. Thus, when the system of this invention is, over time, used on different patients, its more economical to provide than a system wherein the angled tube with rotating tissue working component are a single use device not intended for multiple uses.

[00061] The above is directed to one specific version of the invention. The invention may have features different from what has been described. For example, it should be clear that components other than burs may function as the tissue working component that is applied to the tissue to perform a medical/surgical task. Another type of rotating device that may the tissue working component is a shaver. The handpiece motors that actuate these tissue working components may be electrically, pneumatically or

hydraulically driven. A saw blade that reciprocates may function as the tissue working component. Still other tissue working components may be those that are not actuated with a motor. Ultrasonic tips, electrodes, light emitting head may all function as the tissue working component of this invention. Still other tissue working components may be devices that are manually actuated. These devices include clamps, forceps and scissors.

[00062] Thus the device that extends through tool tube 78 to transmit energy to the tissue working component may be something other than a flexible shaft that rotates. This component of the system of this invention may be: a shaft that reciprocates to transfer a reciprocating motion to the tissue working component' a fiber optic cable; and one or more electrical conductors.

[00063] Likewise, it should be understood that the

components proximal to the tissue working component, more specifically the handpiece, is not limited to the described handpiece with a motor. Other handpieces may have other devices that convert a line voltage into a form of energy that actuates the tissue working component. If the tissue working component is manually actuated, the handpiece may consists of one or more finger grips such that one grip is able to be manually displaced relative to the other grip.

[00064] Likewise it should be appreciated that there is no requirement that there always be an adapter between the handpiece and the tool to removably couple the tool tube 78 to the handpiece 50. For example, US Pat. No. the

Inventor's Assignee's US Pat. No. 5,888,200, MULTI-SURGICAL TOOL SYSTEM, issued 30 March 1999, the contents of which is incorporated herein by reference, discloses a handpiece with a coupling assembly that both removably holds a front end attachment to the handpiece and rotating shaft internal to the handpiece to the output shaft of the motor internal to the handpiece.

[00065] In the ideal configuration of the invention, as described above, the components are selected so that tissue working component 120 projects outwardly beyond the outer circumference of the tool distal section 84 and nose 88. The arrangement facilitates the view of the application of the tissue working component to the tissue. However, the system of this invention can alternatively be formed from components wherein the tissue working component does not project outwardly beyond the tool distal section 84 and nose 88. The system of this invention is still useful because, owing to the angular offset of the tool main section 82 from the distal section 84, the extent to which the tool obstructs the view of the tissue working

component 120 is reduced.

[00066] Further it should be understood that in some versions of the invention the tissue working component is not removably attached to the angled tool that supports the component. In these versions of the invention, the tissue working component is a part of the shaft that is built into the shaft. In these versions of the invention the component internal to the tool that transfers energy to the tissue working component is often likewise built into the tool, in other words, not readily detachable. For example in

versions of the invention in which the tissue working component is an ultrasonic vibrating head, the ultrasonic member forming the head may be essentially fixed to the tool tube 78. In these versions of the invention the

piezoelectric component that converts the electrically energy into mechanical energy that causes the tip assembly to vibrate may also be part of the tool. In these and other versions of the invention, the tool with the bends may be built into the handpiece from which the tool extends.

[00067] Likewise not all of the described components may be in all versions of the invention. For example, it may be possible to eliminate one or more of the spacers that ensure that correct positioning of the bearing assemblies 90, 92, 94, 96, 98 and 100. In these and other versions of the invention, the tube is formed to have one or more internal steps or grooves. The bearing assemblies and related components seat on these steps or in these grooves.

Likewise it may be preferable to form the tube out of plural sections. In some versions of this embodiment of the inventions, the appropriate components are placed in each tube section. The tube sections are welded or otherwise joined together. In these versions of the invention, the tube sections may be constructed so that a joint between two sections forms one of the tube bends.

[00068] Other bearing assemblies may have alternative designs .

[00069] In some version of the invention the shaft that transmits energy to the tissue working member, shaft 124 in the described version of the invention, may be formed with features that facilitate the attachment of the shaft to the handpiece power generating component. If this shaft is intended to rotate or reciprocate longitudinally, these features may be indentations or tabs.

[00070] Further there is no requirement that in all versions of the invention the tool tube 78 have three sections. In some versions of the invention that tool may have a distal section and a main section that is angled from the distal section. In these and other versions of the invention, the tool may be shaped so that the distal section extends rearward a relatively short distance, a maximum of 1.5 cm and sometimes a maximum of 0.5 cm from the distal end of the tool. In these versions of the invention the tool does not include a proximal section that is angled from the main section.

[00071] Similarly, it should be understood that, unless recited by the claims, the quantitative component data set forth in this disclosure are merely exemplarily and not limiting. For example, in versions of this invention wherein the tissue working member include a rotating shaft, it may not be necessary to always space bearing assemblies 96 and 98 equidistantly from the bend between the tool main and distal sections 82 and 84. In some versions of this invention, the end goals of the positioning of the bearing assemblies 96 and 98 may be obtained by simply ensuring that these bearing assemblies are spaced apart a minimum

distance. This minimum distance is typically 2.0 cm or more and often 3.0 cm or more.

[00072] Likewise, while many versions of the invention are configured so the tissue working component extends radially beyond the outer surface of tool distal section 86, this is likewise not a required feature of this invention.

[00073] Similarly, in some configurations of the system of this invention it may not be necessary to employ the access tube. This is the situation when there is no need to define an access channel to the tissue to which the working component is applied.

[00074] Accordingly, it is an object of the appended claims to cover all such modifications and variations that come within the true spirit and scope of this invention.

Claims

What is claimed is:

1. A surgical tool system (30), the system

comprising :

an access tube (32) that has opposed proximal and distal ends and dimensioned and configured for insertion into a living being so as to define an access channel (33) through the access tube to a site internal to the patient adjacent the distal end of the tube;

a tool tube (78) disposed in the access tube (32), the tool tube having opposed proximal and distal ends, wherein the distal end of the tool tube is located adjacent the distal end of the access tube and the proximal end of the tool tube is located adjacent the proximal end of the access tube ;

a tissue working member (120) that extends forward from the distal end of the tool tube (78) for positioning at the site internal to the patent, the tissue working member being configured to perform a task on tissue internal to the patient and a drive member (124) that is connected to the tissue working member for actuating the tissue working member that extends from the tissue working member through the tool tube towards the proximal end of the tool tube; and a handpiece (50) that extends from the proximal end of the tool tube so as to be located proximally from the access tube (32) the handpiece configured for positioning the tool tube in the access tube so the tissue working member can be positioned adjacent the tissue on which the procedure is to be performed, wherein the tissue working member drive member (124) is attached to and controlled by the handpiece,

characterized in that:

the tool tube is formed to have a distal section (84) with a longitudinal axis that defines the distal end of the tool tube and from which the tissue working member (120) extends, and a main section (82) with a longitudinal axis that extends proximally from the distal section wherein the longitudinal axis of the tube distal section is angularly offset from the longitudinal axis of the tube main section and the tube main section is longer in length than the distal section.

2. The surgical tool system of Claim 1, wherein tool tube (78) and the tissue working member (120) are

collectively shaped so that at least a portion of the tissue working member extends radially outwardly from the tool tube distal section (84).

3. The surgical tool system of Claims 1 or 2, wherein the tool tube is further formed to have a proximal section (80) with a longitudinal axis, wherein the longitudinal axis of the tool tube proximal section is angularly offset from the longitudinal axis of the tool tube main section (82) and the tool tube proximal section is the section of the tool tube (78) that extends forward from the handpiece.

4. The surgical tool system of Claim 3, wherein the tool tube proximal section (80) and the tool tube distal section (84) are angularly offset from the tool tube main section (82) so that the tool tube proximal section is parallel with the tool tube distal section.

5. The surgical tool system of any one of Claims 1 to 4, wherein the tool tube (78) is formed so that the tube distal section (84) has a longitudinal axis that is

substantially linear.

6. The surgical tool system of any one of Claims 1 to 5, wherein the tool tube (78) is formed to have a bend (83) between the main section (82) and the distal section (84) of the tube and the bend has a maximum radius of curvature of 15 cm.

7. The surgical tool system of any one of Claims 1 to 6, wherein:

the tool tube is formed to have a bend (83) between the main section (82) and the distal section (84) of the tube; a first bearing assembly (96) is disposed in the tool tube (78) at a location proximal to the tube bend (83) and a second bearing assembly (98) is disposed in the tool tube at a location distal to the tube bend; and

the drive member (124) that extends from the tissue working member (120) is rotatably disposed in the tool tube and suspended in the tool tube by and between the first and second bearing assemblies.

8. The surgical tool system of Claim 7, wherein said first and second bearing assemblies (96, 98) are located approximately equidistantly from the tube bend (83) .

9. The surgical tool system of Claims 8 or 9 wherein a spacer (116) is located internal to the tube adjacent an inner surface of the tube so as to hold said first and second bearing assemblies (96, 98) apart from each other.

10. The surgical tool system of any one of Claims 1 to 9 wherein said tool tube (78) and said tissue working member drive member (124) are releasably attached to the handpiece .

11. The surgical tool system of any one of Claims 1 to

10, wherein the handpiece includes a motor (52) for

actuating the drive member (124) and the tissue working member (120) .

12. The surgical tool system of any one of Claims 1 to

11, wherein the tissue working member is one from the group consisting of: a drill bit; a bur; a rasp; a shaver; and a saw blade.

13. The surgical tool system of any one of Claims 1 to

12, wherein:

the tool tube (78) extends distally forward from a foot ( 62 ) ; and

said foot (62) is releasably connected to the handpiece (50) so as to releasably hold the tool tube to the

handpiece .

14. A tool tube (78) for use with the system (30) of any one of Claims 1 to 13, said tube comprising:

an elongated tube (78) that has opposed proximal and distal ends and a lumen (79) for holding a drive member (124) of a tissue working member,

characterized in that:

the tube is formed to have a distal section (84) with a longitudinal axis that defines the distal end of the tool tube and from which the tissue working member extends, and a main section (82) with a longitudinal axis that extends proximally from the distal section wherein the longitudinal axis of the tube distal section is angularly offset from the longitudinal axis of the tube main section and the tube main section (82) is longer in length than the distal section.

15. The tool tube (78) of Claim 14, wherein the tube distal section (84) has a length of less than 5 cm.

16. The tool tube (78) of Claims 14 or 15, wherein the angular offset between the tube main section (84) and the tube distal section (86) is less than 14°.

17. The tool tube (78) of any one of Claims 14 to 16, wherein the tube has a maximum outer diameter of 0.8 cm.

18. The tool tube (78) of any one of Claims 14 to 17, wherein the tube is further formed to have a proximal section (80) with a longitudinal axis, wherein the

longitudinal axis of the tool tube proximal section is angularly offset from the longitudinal axis of the tool tube main section (82) and the tool tube proximal section is the section of the tool tube (78) that extends forward from the handpiece .

19. The surgical tool system of Claim 18, wherein the tool tube proximal section (80) and the tool tube distal section (84) are angularly offset from the tool tube main section (82) so that the tool tube proximal section is parallel with the tool tube distal section.

20. The tool tube of any one of Claims 14 to 19, wherein the tube (78) is formed so that the tube distal section (84) has a longitudinal axis that is substantially linear .

21. The tool tube (78) of any one of Claims 14 to 20, wherein the tube (78) is formed to have a bend (83) between the main section (82) and the distal section (84) of the tube and the bend has a maximum radius of curvature of

15 cm.

22. The tool tube (78) of any one of Claims 14 to 21, wherein :

the tool tube is formed to have a bend (83) between the main section (82) and the proximal section (84) of the tube; and

a first bearing assembly (96) is disposed in the tool tube (78) at a location proximal to the tube bend (83) and a second bearing assembly (98) is disposed in the tool tube at a location distal to the tube bend and said bearing assembly being to rotatably hold a rotating shaft (124) in the tube lumen (79) .

23. The tool tube (78) of Claim 22, wherein said first and second bearing assemblies (96, 98) are located

approximately equidistantly from the tube bend (83) .

24. The tool tube (78) of Claims 22 or 23, wherein a spacer (116) is located internal to the tube adjacent an inner surface of the tube so as to hold said first and second bearing assemblies (96, 98) apart from each other.

25. The tool tube (78) of any one of Claims 14 to 24, wherein integral with the proximal end of the tube are features for cooperating with a handpiece (50) to releasably hold the tube to the handpiece.