WO1997014347A1

WO1997014347A1 - Adjustable arm instrument holder

Info

Publication number: WO1997014347A1
Application number: PCT/US1996/016765
Authority: WO
Inventors: Anthony A. Nobles; Charles L. Jech; Kwok-Yeung A. Lai; Benjamin G. Brosch, Jr.
Original assignee: Nobles-Lai Engineering, Inc.
Priority date: 1995-10-16
Filing date: 1996-10-16
Publication date: 1997-04-24
Also published as: AU7457396A

Abstract

The present invention is an adjustable arm instrument holder (15). The adjustable arm (19) comprises a dual helical spring shaft (33 and 35) coated with a flexible plastic material (31). Attached to an end of the adjustable arm (19) is a ball joint (76) that allows an instrument holder (15) to swivel on the ball joint (76) for proper positioning. The instrument holder (15) comprises a plunger mechanism (57) to lock its position in place on the ball joint (76) and a clamping mechanism (25) for strongly grasping the instrument or device (29). The plunger mechanism (57) comprises a release lever (66) that upon depression releases the lock (57) on the ball joint (76) to allow the operator to swivel the instrument holder (15) into position. The clamping mechanism (25) comprises an adjustable hook (62) to accommodate different-sized instruments (29).

Description

ADJUSTABLEARMINSTRUMENTHOLDER

RELATED APPLTCA TOW This application claims the benefit of United States Provisional Patent Application Serial No. 60/005,473 filed October 16, 1995, the disclosure of which is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

In many medical procedures, it is imperative that medical devices and instruments are held steady without movement. This is especially true with neurosurgery procedures where delicate brain tissue can easily be unintentionally destroyed or damaged with only a slight inadvertent movement of the instrument.

To address this need, instrument holders are available to hold medical devices in place. However, these instrument holders do not exert enough force to grip the instrument and hold it in place, or they do not provide the required stability for heavy devices. Generally, the instrument holder must allow the medical practitioner to smoothly translate the instrument or device to the desired position, and be stable enough to maintain the position of the instrument or device during the procedure. Unfortunately, with the use of heavy instruments such as endoscopes and cannulas, the weight supported by the instrument holder increases to a point where the instrument holder bends, loses stability, or loses the grip on the instrument allowing the instrument to move out of position.

What is needed is an instrument holder that can securely grip a surgical instrument or device, allows smooth and accurate positioning of the instrument or device, and is strong and stable, so that the instrument or device will not move out of position during the procedure.

SUMMARY OF THF. INVENTION

The present invention is an adjustable arm instrument holder. The adjustable arm comprises a dual helical spring shaft coated with a flexible plastic material. Attached to an end of the adjustable arm is a ball joint that allows an instrument holder to swivel on the ball joint for proper positioning. The instrument holder comprises a locking means to lock its position in place on the ball joint and a grasping means for strongly grasping the instrument or device. The locking means comprises a release lever that upon depression, releases the lock on the ball joint to allow the operator to swivel the instrument holder into position. The grasping means comprises an adjustable hook to accommodate different sized instruments.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be better understood with reference to the drawings wherein some similar reference numerals are used in different parts and embodiments to indicate similar structures; wherein

FIG. 1 is a plan view of an adjustable arm instrument holder of the present invention;

FIG. 2 is a plan view of an instrument held by the adjustable arm instrument holder of the present invention; FIG. 3 is a plan view, partially in cross section of the flexible arm illustrated in FIG. 1 taken along line 3-3;

FIG. 4 is a plan view cf the instrument holder illustrated in FIG. 1 attached to a ball joint of a flexible arm;

FIG. 5 is a longitudinal cross-section of the instrument holder illustrated in FIG. 4;

FIG. 6 is a top view of a swivel body;

FIG. 7 is an end view of the swivel body of FIG. 6 taken along line 7-7;

FIG. 8 is a cop view of a grasper body; FIG. 9 is an end view of the grasper body of FIG. 8 taken along line 9-9;

FIG. 10 is an end view of a swivel lock lever illustrating the end that connects to a plunger;

FIG. 11 is a top schematic view of a locking plug; FIG. 12 is a cross-section view of the locking plug of FIG. 11 taken along line 12-12;

FIG. 13 is aπ end view cf the locking plug of FIG. 11 taken along line 13-13;

FIG. 14 is an end view of the locking plug of FIG. 11 taken along line 14-14;

FIG. 15 is an end view of a lock plate; FIG. 16 is a top view cf an end cap;

FIG. 17 is an end view of the top plate of FIG. 16 taken along line 17-17; FIG. 18 is a side view of the top plate of FIG. 16; FIG. 19 is a top view of a lock carrier;

FIG. 20 is an end view of the lock carrier of FIG. 19 taken along line 20-20; FIG. 21 is a longitudinal cross-section of the lock carrier of FIG. 19;

FIG. 22 is a top view of a hook used for grasping instruments; FIG. 23 is a side view of the hook of FIG. 22;

FIG. 24 is a top schematic view of a locking pawl to lock the hook of FIG. 22 in place;

FIG. 25 is a side view of the locking pawl of FIG. 24_; FIG. 26 is a top view cf a cam; FIG. 27 is a side view of the cam of FIG. 26;

FIG. 28 is an end view of the cam of FIG. 26 taken 90 degrees away from the view cf FIG. 27;

FIG. 29 is a top schematic view of a ball joint release lever; FIG. 30 is a side view of the release lever of FIG. 29;

FIG. 31 is a schematic side view of a hook release lever; FIG. 32 is a top view cf the hook release lever of FIG. 31 FIG. 33 is a schematic bottom view of the hook release lever of FIG. 31; FIG. 34 is a side view of a release knob pin;

FIG. 35 is an end view of the release knob pin of FIG. 34; FIG. 36 is a schematic end view of a spring housing; FIG. 37 is a schematic side view of the spring housing of FIG. 36; FIG. 38 is a plan side v ew of an alternate embodiment of an instrument holder of the present invention further illustrated in FIGS. 39-54 below;

FIG. 39 is a longitudinal cross-section of the instrument holder illustrated in FIG. 33; FIG. 40 is a top view cf a swivel body;

FIG. 41 is a side view of the swivel body of FIG. 40; FIG. 42 is an end view of the swivel body of FIG. 40 taken along line 42-42;

FIG. 43 is a side view of a grasper body; FIG. 44 is an end view cf the grasper body of FIG. 43 taken along line 44-44;

FIG. 45 is an end view cf the grasper body of FIG. 43 taken along line 45-45; FIG. 46 is a side view cf a hook for grasping instruments;

FIG. 47 is an end view of the hook of FIG. 46 taken along line 47-47;

FIG. 48 is a schematic end view of a spring housing; FIG. 49 is a schematic side view of a spring housing of FIG.

48;

FIG. 50 is a schematic side view of a hook clevis;

FIG. 51 is a schematic end view of the hook clevis of FIG. 50; FIG. 51a is a schematic bottom view of the hook clevis of FIG. 50;

FIG. 52 s an end view of a hook shoe;

FIG. 53 is a side view of the hook shoe of FIG. 52;

FIG. 54 is an end view of a lock ring; and FIG. 55 is a side view of the lock ring of FIG. 54

DETAILED DESCRIPTION

The present invention s directed to an adjustable arm for holding instruments that are particularly useful in medical applications. A preferred embodiment of the present invention is illustrated in FIGs. 1 and 2. The adjustable arm assembly comprises a holder, generally designated 15, with a clamping mechanism, generally designated 25, at one end and with a ball joint assembly, generally designated 27, at the other end. The clamping mechanism holds a medical instrument 29 such as the cannula shown. The oall joint assembly threadably connects to a flexible arm 19 wmch is threadably connected to a rigid arm 17 at a threaded connection, generally designated 11. The rigid arm and hence the adjustable arm assembly is secured at its base with a foundation attachment 13. The foundation attachment can be any conventional means for attachment, such as a bolt or a clamp capable of securely fixing the assembly to an examination or surgical table In the alternative, the assembly could be attached to a wall or other stationary object. As stated, the rigid arm 17 is connected to the foundation attachmen . The rigid arm can be curved and has a female internally threaded end 21. The rigid arm is made out of a rigid material such as stainless steel. The rigid arm can be

- completely solid or a hollow tube. The flexible arm 19 has a male connector 23 at one end for threadably attaching to the female end 21 of the rigid arm 17. The opposite end of the flexible arm connects to the ball joint assembly. Referring additionally to FIG. 3, the flexible arm 19 is manufactured by Moffatt Industries and is made out two springs 33 and 35. The first spring 35 is circular in cross section, and the second spring 33 is triangular in cross section, with a flat side 36 aligning axially with the external edge of the arm. The outer surface of the arm is coated with a flexible plastic material 31. The two springs of the flexible arm give the arm an appropriate amount of stiffness to hold surgical instruments without flexing. The arm can securely and stably hold up to at least ten pounds without flexing. Preferably, the arm can support the torque created by twenty pounds of weight held by the clamping mechanism. The arm is flexible enough, however, to allow the operator to freely move the arm with ordinary strength.

Attached to the ball joint is the swivel/grasper instrument holder 15, which is illustrated with more detaii in FIG 4. The swivel/grasper comprises two subassemblies, the swivel assembly located on the proximal end and attached to the ball joint, and the grasper assembly located on the distal end which attaches the surgical device such as a cannula as illustrated in FIG. 2. Proximal and distal as used herein are defined with reference to the foundation attachment.

The swivel assembly comprises a swivel body 54, illustrated in more detaii m FIGS. Ξ, 6, and 7. The swivel body is preferably made out of aluminum although other materials can be used. A ball fitting 68 which is made out of stainless steel and which is threaded into a female threaded end 40 of a stainless steel ball 76, is secured to the flexible arm using a distal male threaded termination 20 of the flexible arm and a lock nut 69. The ball 76 with the threaded end 40, is held in the swivel body such that the threaded end extends toward an opening 41 in the proximal end of the swivel body. A plunger 57 (illustrated in FIG. 5 in cross section) which is circular m that it comprises a concave arcuate side 42, is slidably held in the swivel body with the arcuate side 42 of the plunger contacting the ball. At the distal end of the plunger is a bore 37 that a roll pin 72 fits into. The pin acts as a pivot point for the swivel lock lever 56 to pivot around. The swivel body further comprises four equally spaced bores 93 located near the edge of the swivel body to receive screw for attaching the swivel body to the remainder of the holder. The distal end of the swivel body also comprises a channel 91 to receive the proximal end of the hook 62 when the hook is in the most proximal position, and it also has a central bore 92 to receive the parts of the swivel assembly.. The next part of the swivel subassembly is the locking plug 58 (better illustrated in FIGS. 11-14) which has a bevel 105 on its insertion end. The rectangular swivel lock lever 56 (better illustrated in FIGS. 5 and i:) is placed inside the locking plug 58 through holes 87 and 113. The swivel lock is placed such that the bore 103 in the swivel lock lever is located proximally and is accessible through hole 127. An internally threaded hole 109 is provided at the distal end of the locking plug. A set screw 81 (FIG. 5) is threaded ir.to the threaded hole for applying pressure to set screw engagement end 50 of the swivel lock lever 56 opposite the release lever engagement end 51. The swivel lock lever can be made out of stainless steel and the locking plug can be made out of aluminum although other suitable materials may be used. The locking plug with the swivel lock lever is then placed into the swivel body such that the distal end of the plunger 57 fits into hole 107 at the pm 72. The pin engages the bore 103 in the swivel lock lever and acts as a fulcrum for the swivel lock lever. The iccKing plug also has a release lever receiving area 111 into whicn the release lever is inserted.

Lock plate 59 isee FIG. 15) is circular and symmetrical and has two large openings 110, one at the top and one at the bottom. There are also six small openings 116 which are internally threaded to receive six set screws that lock the lock plate tight against the locking plug. The perimeter of the lock plate is externally threaded and corresponds with internal threads in the swivel body. The lock plate is threaded into the swivel body to secure the locking plug. One of the two larger holes in the lock plate is for having access to the set screw hole 109 of the locking plate and the set screw 81 that exerts force onto the swivel lock lever. The lock plate is threaded inside the lock body until a desired fit is achieved and one of the two large holes aligns with the set screw of the locking plug.

The swivel release lever 66 (better illustrated in FIGS. 29 and 30), having an actuation arm 161, and locking arm 163, is installed in the swivel body. At the aperture 167 is provided a small swivel lever engagement dowel pin 77 (see FIG. 5) . The swivel release lever with the small dowel pin is inserted into the swivel body by inserting the pivot portion with hole 165 into the hole 87 of the swivel body 54 and aligning holes 85 (FIGs. 4, 11, and 12) of the swivel body and locking plug, and hole ₁65 of the swivel release lever. The swivel release lever is secured by placing a pivot pin 78 through holes 85, 165 and locating it in holes of the locking plate and swivel release lever. The pivot pin serves as a pivot point for the swivel release lever and secures the swivel release lever to the locking plug. The pin does not extend into the swivel body.

Six set screws are inserted into the six threaded small holes of the lock plate . The set screws force the locking plug with the swivel release lever proximally such that the pin securing the release lever to the locking plug is no longer in alignment with the holes 85 in the swivel body making sure the release lever stays secure.

The spring housing 74 (better illustrated in FIGS. 36 and 37) is next fitted into the swivel body making sure that the small holes 115 align with the lock plate holes, and the spring hole 183 aligns with spring receiving hole 89 of the swivel body. A compression spring 83 is then placed in hole 183. Spring cap 75 is then placed over the spring, under the swivel release lever 66, and into the counter bore 181. The spring cap has an arcuate top surface 185 to assure smooth engagement with the actuation arm 161. The spring housing also provides an access channel 177 allowing access to the swivel lock lever set screw 81. This completes the swivel subassembly. The swivel unit operates as follows: The spring 83 inside the spring housing 74 exerts a force on the spring cap and release lever such that the release lever is biased in an upward position. The small dowel pin 77 of the release lever is then in a position that exerts a force on the swivel lock lever 56 which in turn exerts a force on the plunger making a tight friction fit around the ball 76 and keeping the ball in place. When an operator presses the release lever towards the swivel body, the release lever pivots around the pivot pin 78 and the locking plug, release lever, and the small dowel pm move slightly distally releasing the force on the swivel lock lever and thus, the force on the plunger. This frees the ball 76 and allows the operator to swivel and rotate the swivel unit around the ball until it s in the desired position. Then the operator allows the release arm to go back to its resting position. The small pin 77 then moves proximally and the force applied to the swivel lock lever is reestablished securing the swivel unit to the ball oint . The grasper suoassembly oegms with a generally cylindrical and annular grasper body 55 (better illustrated in FIGS. 8 and 9) , preferably manufactured from 6061-T6 aluminum, having a front end which mates with the swivel body 54 and a rear end which mates with an end cap 60 (better illustrated in FIGS.16-18) . The grasper body defines a rectangular through hole 101 to receive the other parts of the grasper assembly. Four longitudinal bores 93 penetrate the wall of the body and four more bores 119 penetrate the end cap. The end cap also has recesses 121 to receive the heads of the fasteners so that they do not protrude above the top of tne end cap. The bores are spaced at 90 degree intervals and are located at approximately the mid-thickness of the wall. They are located at 45, 135, 225 and 315 degrees around the body These bores are designed to accommodate fasteners (screws) for connecting the body to the swivel body (see corresponding holes 93) and end plate sections. The proximal end of the grasper body has an alignment protrusion 99 to mate with the central bore 92 (FIG. 7) on the swivel body. A similar configuration is utilized between the alignment protrusion 117 of the end cap 60 and a counter bore 102 on the grasper body. The top 115 of the end cap extends distally to provide a surface for engaging the medical device and against which the hook 62 can clamp the medical device. The top of the end cap is further provided with a hook receiving aperture 123 which slidably receives the hook 62.

Two bores 95 and 97 aligned along the longitudinal axis of the grasper body radially penetrate the body. The smaller bore 97 closest to the proximal end of the grasper body is designed to accommodate an annular cam sleeve 65 (FIG. 5) , while the larger bore closest to the distal end is designed to accommodate a spring housing 127 and sprmg retainer 71. The inner surface at the lowest portion of the grasper body (i.e., the portion of the body between 135 and 225 degrees) has a hook receiving channel 128 along the grasper body longitudinal axis.

A member designated herein as the lock carrier member 61 has a channel 133 shaped lower cross section spanning the length of the member, beveled corners 126, and a knob pin receiving channel 130. (See FIGS. 19-21) . The proximal upper section is penetrated by a longitudinal opening 135. The lower channel is deep enough to accommodate tne hook 62 (see FIGS. 5, 22 and 23) and a locking member 63 (see FIGS. 24 and 25) for locking the hook. The hook has teeth 141 on the upward proximal surface of an attachment arm 137 used to secure the hook to the assembly.

A clamping arm 139 extends from the attachment arm 137 and curves over the top 115 of the end cap. The clamping arm has a recess

140 to receive the medical device and hold it against the top 115 of the end cap. The lockmg member referred herem as the locking pawl has teeth 151 on its lower surface, mated to the teeth of the hook ana protruding from a proximal most portion of the pawl's lower face. The pawl is pivot mounted through hole

147 in the pawl and 131 in the carrier member (FIG. 21) with pivot pm 79 (see FIG. 5) about a transverse axis within the lower channel. The hook is slidably fitted directly below the pawl and within the lower channel of the lock carrier with the teeth of the hook facing the teeth 151 of the pawl. The distal portion of the pawl forms a channel 150 to engage a knob p 70.

The knob pin is pivotally secured into the channel 150 with a pivot pin 80 inserted through apertures 149.

Two vertical openings, a round distal opening 129 and a square proximal opening 125 are formed on the lock carrier 61. The proximal opening is offset from the central longitudinal axis of the lock carrier, while the distal opening is on the axis.

The distal opening is stepped into the channel opening 133 toward the lower section of the lock carrier. When installed in the grasper body, the distal opening of the lock carrier is aligned with the distal bore 95 cf the grasper body and the channel opening 150 of the pawl. The release knob p 70 (see FIGS. 34 and 35) , having an outer diameter slightly smaller than the inner diameter of the lock carrier channel opening is mserted through the distal bore and opening and is sandwichly and pivotally engaged using the base 173 and bore 175 and pivot pm 80 by the pawl distal channel section. The curved base of the knob pm allows the knob pm to pivot m the channel. A compression coil sprmg 84 is then inserted t rough the distal body bore encasing the release knob pm. The sprmg diameter is larger than the smallest distal cnannel opening diameter and, thus, it sits on the step formeα between tne cwo different diameter distal openings. A cylindrical spring retainer 71 (see FIG. 5) is positioned over the sprmg and release knob pin. A release button 73 is placeα on the spring retainer. The retainer engages the release knob pm. The sprmg exerts a force upward aga st the retainer which exerts a force upward on the release knob pin which m turn pivots the pawl about its mount on the lock carrier causmg the pawl teeth to engage the hook teeth. To release the teeth, the retainer is pus.ned down causmg the pawl teeth to pivot off the hook teeth.

When the locκ carrier s installed, the carrier proximal opening s in i_ne with tr.e body proximal bore. A cam 64 (see FIGS. 26-28) is fitted thro gn the forward bore and opening. The cam has a cylindrical upper section 153 and an approximately semi-cylmdricai xower section 157. The lower section has a greater radius than the upper section, and the upper section mcludes a flat 155 for engaging in a rotationally fixed manner a release lever 67 (FIGs. •= and 5) The central longitudinal axis of the upper section s offset from, but parallel to, the central longitudinal axis of the lower section. A lip 159 protrudes vertically from a portion of the periphery of the lower cam section. When installed the cam lip may rest against the upper surface of the pawl, the cam lower section is encased by the lock carrier and the upper section protrudes through the upper body. The cylindrical cam sleeve 65 (see FIG. 5) is fitted into the proximal bore of the body encasing the upper section of the cam. A cylindrical plunger 44, (see FIG. 5) preferably made of brass, is fitted in the longitudinal bore of the lock carrier and rests against the cam lower section. Bellvile washers 46 or a spring are then inserted ir. the longitudinal bore. A set screw 82 is screwed at the end of the bore to retain the plunger against the cam within the carrier when installed. A rotatable handle or release lever 67 (see FIGS. 31-33) is perpendicularly connected to the portion 153 of the cam protruding through the grasper body with bottom opening 171 in the release lever 67. The lever has a threaded opening to receive a set screw t engage the flat 155 of the cam. The lever allows one to rotate the cam about the upper cam section central longitudinal axis which is cffset from the lock carrier central vertically longitudinal plane. By rotating the cam, the cam lip is rotated on or off from the upper surface of the pawl.

To engage an object with the hook, the lever is turned to rotate the lip off the pawl . Pressure is then applied against the spring retainer to pivot and disengage the pawl teeth off the hook teeth. Simultaneously, the hook is then slidably opened and the medical device is placed in its grip. The hook is then moved towards the body to grip the medical device. Once in position, the pressure is released from the spring retainer and the spring force pivots the pawl engaging the prowl teeth against the hook teeth. 3y turning the lever, the cam lip engages the upper surface of the pawl locking the pawl teeth on the hook teeth. At the same, time the offset lower cam section rotatably pushes against the plunger which pushes against the Bellvile washers and the set screw causing the lock carrier with the locked hook to slide within the body further gripping the object. When this occurs the Bellvile washers provide a spring loaded grip against the object. Although the pawl and hook teeth have a set pitch, the Belleville washers or spring provide a further benefit in that they provide a spring gripping force against an object when a single tooth adjustment provides too little or too much gripping force against an object. Turning now to FIG. 33, an alternate embodiment of the present invention is illustrated. This embodiment, generally referred to with reference numeral 200, also comprises a swivel assembly and a grasper assembly. The swivel assembly is similar to, although not identical to, the swivel assembly of the first embodiment detailed above. FIG. 38 illustrates the distal end of the flexible arm 19 with an externally threaded male end fitting 20 (the tnreads are not illustrated) . The male fitting is threaded into the ball fitting 268 which has a ball joint 276 attached. The ball joint fitting is secured to the male end fitting via set screw 282. The ball joint is secured within the swivel body 254, and upon depression of the swivel release lever 266, releases the ball for full freedom of movement of the instrument holder around the ball. Bolted to the swivel body is a grasper body 255 with an integral hook 411 and hook shoe 332 and a movable hook 262. As described below, rotation of knob 267 translates and pivots the movable hook to grasp a medical instrument.

FIG. 39 illustrates the second embodiment in longitudinal cross section. The swivel assembly is preformed prior to the grasper assembly. The first step of the swivel assembly is to place around the stainless steel ball joint 276 ball shoe 321 which gives additional gripping support to the ball. The shoe is preferably made of a plastic material such as delrin or the like. The ball joint is then placed into the swivel body such that the threads of the ball joint protrude from aperture 410.

The next step of the assembly is to construct a locking plug subassembly. First the plunger insert 279 is placed within the plunger 257. A rolled pin 272 is inserted into a bore at the distal end of the plunger similar to the first embodiment. Next, a swivel lock lever 256 is inserted into the locking plug 258 which for all practical purposes is identical to the locking plug 58 described above. Set screw 281 is then inserted into the threaded set screw aperture cf the locking plug such that the set screw protrudes slightly into the hole for the locking plug. The locking plug assembly is then positioned into place within the swivel body. The swivel release lever 266 is then assembled by placing a dowel pin 277 into the partial aperture as described above. The release lever is then positioned into place in the swivel body by positioning the proximal end through the swivel release lever aperture 401 in the swivel body (see FIG. 40. The release lever is position similar as in the first embodiment making sure that all of the apertures corresponding with pivot pin aperture 285 are aligned (the apertures in the swivel body, locking plug and release lever) . Once all the apertures are aligned, a pivot pin 278 is passed through the swivel body and into the locking plug and release lever. The pivot pin is only as wide as the locking plug, and thus, is not attached to the swivel body. The next step is to position a lock ring 426 (better illustrated in FIGS. 54 and 55) into a circular notch 428 within the swivel body. The lock lever is placed using a lock lever tool that has two prongs which mate with apertures 428 and squeeze the apertures closer together to reduce the diameter of the lock ring. Care is made to position the lock ring with the opening neat the apertures at the bottom of the swivel body such that access is allowed to the set screw 281 within the locking plug. The lock ring is placed within the circular notch by translating the locking plug assembly slightly proximally such that the pivot pin 285 is no longer in alignment with the pivot pin apertures 278 in the swivel body. Once the lock ring is in position, the set screw 281 is adjusted to exert the proper force on the swivel lock lever 256 in concert with the swivel release lever arm in its resting position. The set screw is adjusted using an Allen wrench to thread the set screw partially out of the set screw aperture within the locking plug.

Next, a spring cap 275 and spring 283 are inserted into the spring cap aperture 423 of the spring housing 274 (better illustrated in FIGS. 48 and 49) and then the assembly is inserted into the swivel body with the spring cap protruding out of the spring cap aperture 403. Optionally, the spring cap housing can be left out of the assembly with only the spring cap and spring being inserted directly into the swivel body and the spring cap protruding through aperture 403. The spring and spring cap with or without the spring housing are retained in place with a spring retaining screw 325 that is threaded at its bottom portion to mate with the threaded aperture 407 of the swivel body and optionally the threaded aperture 422 of the spring housing. Once the spring retaining screw is positioned. The swivel assembly is complete.

The next step is to assemble the grasper assembly. FIGS. 39 and 43-45 illustrate the grasper body of this embodiment. The grasper body has an integral hook 411 that is T shaped in cross- section (see the end view in Fig. 44) . The distal end of the grasper body (see FIG. 44) has five apertures, a large hook aperture 413 and four bolt bores 409. The proximal end of the grasper also has five apertures, the four bolt apertures and a larger hook body aperture 415. As illustrated in FIG. 39, the two larger apertures meet neat the distal end of the grasper body.

The grasper is assembled by first placing the hook 262 (better illustrated in FIGS. 46 and 47 into a reaction bracket 327 (better illustrated in FIGS. 50, 51 and 51a) . The hook is aligned such that the reaction bracket pivot aperture 419 is in line with the pivot aperture 286 of the reaction bracket. The hook and reaction bracket are connected by a pivot pin 280 through the pivot apertures.

The reaction bracket has a reduced circular diameter protrusion 425 at the bottom of the bracket. The circular protrusion is sized such that a compression sprmg 284 fits around the diameter and is held in place with lip 424 and the floor 416 of aperture 415. The protrusion has a threaded aperture 430. A lock shaft 331 with a threaded top portion is threaded into the threaded aperture of the protrusion. The lock shaft has two threaded diameters, a larger top diameter that is larger than the lock shaft aperture 415 of the grasper body and a smaller bottom diameter that fits within the lock shaft aperture 415. The hook with the now attached reaction bracket and lock shaft are placed within the grasper body such that the distal end of the hook protrudes through the hook aperture 413 and the lock shaft protrudes through the lock shaft aperture 417. The reaction body has a top chamfer 424 to assist in positioning the reaction bracket within the grasper body.

Next the hook is secured to the grasper body via a pivot pin placed through the stationary pivot aperture 286 of the grasper body and the pivot aperture 421 of the hook using a long length pivot pin 299. This pivot pm fixes the hook to the grasper body such that it pivots around the axis of the pivot pin 299.

Next, a lock sleeve 330 is placed over the bottom of the lock shaft and within the aperture 417; the aperture 417 being stepped to receive the lock sleeve (see FIG. 39) . A lock washer 329 is then placed over the lock shaft and then the lock knob 328 is threaded onto the lock shaft's bottom portion. The lock knob is secured using a set screw 300 (see FIG. 38) in a set screw aperture 302 of the lock knob. The next step is to secure the grasper assembly to the swivel assembly with four fasteners such as bolts. The fasteners are threaded through the grasper body into the swivel body through the bolt apertures 409 of the grasper and swivel bodies and tightened to secure the two assemblies together Finally, a hook shoe 332, made out of a rubber like material such as delrin, is positioned over the T shaped integral hook 411 of the grasper body. The hook shoe provides a high friction surface for grasping a medical instrument.

Thus, an adjustable arm instrument holder is disclosed which allows for the flexible manipulation of a medical device or instrument through a flexible arm and a ball joint that when locked into position keeps the medical device or instrument spatially fixed during the procedure. While embodiments and applications of this invention have been shown and described, it would be apparent to those skilled in the art that many more modifications are possible without departing from the inventive concepts herein. For example, the materials listed are only one preferred type of materials, many other suitable steralizable metals, rubbers, and plastics could be used to create this invention. The dimensions and relative size and shapes of many components could be changed and still have a very useful adjustable arm instrument holder for medical applications. The invention, therefore, is net to be restricted except in the spirit of the appended claims.

Claims

WHAT IS CLAIMED IS:

1. An adjustable arm medical instrument holder comprising:

(a) a flexible arm; (b) a ball joint attac ed to the flexible arm

(c) a swivel assembly attached to the ball joint comprising

(1) a housing;

(2) a movable plunger that engages the ball joint within the housing; (3) a swivel lock lever with a first and second end connected to the movable plunger;

(4) a fixed point relative to the housing connected to the first end of tne swivel lock lever;

(5) a movable pomt relative to the housing connected to the second end cf the swivel lock lever; and

(6) a means for controlling the movable point connected to the movable point; and

(d) a grasper assembly attached to the swivel assembly.

2. The adjustable arm medical instrument holder of claim 1 wherein the grasper assembly comprises a housing and a movable hook partially within the housing.

3. The adjustable arm medical instrument holder of claim 2 wherein the grasper assembly ^' further comprises means for adjusting the movable hook.

4. The adjustable arm medical instrument holder of claim

3 wherein the movable hoo is slidably retamed within the housing and the adjusting means comprises a release button attached to a lockmg pawl .

5. The adjustable arm medical instrument holder of claim

4 wherein the lockmg pawl and the movable hook have mating serrations .

6. The adjustable arm medical instrument holder of claim 4 wherein the adjusting means further comprises a hook release lever attached to a cam shaft which pivots over the locking pawl to thereby lock the locking pawl into engagement with the movable hook or to release the locking pawl from engagement with the movable hook.

7. The adjustable arm medical instrument holder of claim 3 wherein the movable hook pivots relative to the grasper housing and is pivotally connected to the grasper housing.

8. The adjustable arm medical instrument holder of claim 7 wherein the adjusting means comprises a rotatable knob attached to a reaction bracket and the reaction bracket is attached to the movable hook whereby rotation of the rotatable knob causes the reaction bracket to move relative to the housing and causes the movable hook to pivot relative to the housing.

9. An adjustable medical instrument holder comprising: a flexible arm comprising two helical springs, one being circular and the other being triangular in cross section; a ball joint connected to the flexible arm; a swivel housing connected to the ball joint; a movable plunger within the swivel housing to grasp the ball joint; means for controlling the plunger connected to the plunger and the swivel housing; a grasper housing connected to the swivel housing; a movable hook retained within the grasper hosing; and means for controlling the movable hook.

10. The adjustable arm medical instrument holder of claim 9 further comprising a rigid arm connected to the flexible arm.

11. The adjustable arm medical instrument holder of claim 9 further comprising a swivel lcck lever connected the plunger.

12. The adjustable arm medical instrument holder of claim 9 further comprising a swivel release lever connected to the swivel lock lever which comprises the means for controlling the plunger.

13. The adjustable arm medical instrument holder of claim

9 wherein the means for controlling the movable hook comprises a rotatable knob attached tc a reaction bracket attached to the movable hook.

14. A method of positioning a medical instrument comprising the steps of :

(a) positioning the medical instrument in an instrument holder with a movable hook; (b) moving the movable hook to grasp the instrument;

(c) swiveling the instrument holder around a ball joint; and

(d) locking the instrument into relative position to the ball joint by moving a plunger within the instrument holder.