CA2483116C - Method and instruments for positioning humeral component during shoulder arthroplasty - Google Patents

Abstract

The present invention relates to a set of tools and accessories used for properly positioning a stemmed humeral component, and/or a humeral stem provisional, within a canal in the humerus. The set of tools and accessories includes one or more fin clamps that are configured to be temporarily attached to a fin on the humeral component or the provisional; a ruler that is configured to be attached to the arm of the fin clamp, a fixation pin and pin driver configured to be used with the other tools for marking a position on the humerus; and one or more sleeves that are configured to slide over the stem of the humeral stem provisional to maintain it in the desired position.

Description

METHOD AND INSTRUMENTS FOR POSITIONINCr NUMERAL
COMPONENT DURING SHOULDER ART HROPLASTY
z The present invention relates generally to obtaining the proper 2 position of a prosthetic implant, and more specifically to devices and methods 3 used for achieving the proper axial position and retroversion of a stemmed 4 Numeral component during shoulder arthroplasty, as well as to properly s positioning a Numeral stem provisional, which is inserted on a trial basis during 6 the operation, prior to inserting the permanent stemmed Numeral component.
BACKGROUND OF THE INVENTION
Shoulder fractures are not uncommon, especially among senior 9 citizens with osteoporosis. In certain instances, shoulder replacement surgery is to necessary. One type of fracture that commonly requires shoulder replacement 1 i surgery is called a four-part fracture. Such a fracture is characterized by the 12 shoulder being broken into four parts -- the lesser tuberosity, the greater 13 tuberosity, the Numeral head, and the Numeral shaft.
14 During a shoulder replacement operation (also known as shoulder Zs arthroplasty surgery), a canal found within the Numeral shaft is used for i6 receiving the Numeral component of the. shoulder prosthesis. If necessary, in i7 order to better accommodate the Numeral component, the canal may be m enlarged using known methods. The Numeral component of the prosthesis 19 typically includes a stem and a head, which is a partial sphere that replaces the 2o fractured Numeral head. The stem and the head may be two separate 2t components, or they may be a single component. Regardless of whether the 22 Numeral component is a single part or two parts, a collar is formed between the 1 stern and the head. Between this collar and the fracture line on the proximal 2 end of the humerus, the fractured lesser and greater tuberosities are normally 3 anchored around the stern of the Numeral component, as closely as possible to 4 their original positions.
s Before implanting the permanent stemmed Numeral component., a 6 temporary component, often called a Numeral stem provisional, is temporarily inserted into the humerus to determine the proper placement of the stemmed s Numeral component. Proper positioning of the f nal stemmed Numeral 9 component is very important. Improper positioning can result in a range of to problems from -mild discomfort to severe pain, as well as a lack of proper range t 1 of motion, depending upon the degree and type of improper positioning.
12 Accordingly, it is important that the Numeral stem provisional be properly i3 positioned, and that such proper position can be reliably replicated when 14 implanting the final stemmed Numeral component. Th~.e two key areas of proper Is positioning are the stemmed component's axial position and its retroversion.
i6 Currently, several devices are available to assist in properly m positioning the stemmed Numeral component within the humerus. For example, is Tornier~ markets a system under the Aequalis~ name that includes a jig that 9 uses a portion of the anatomy for referencing the position of the Numeral 2o implant. However, this jig is relatively large and bulky, and it is difficult to 21 perform a range of motion analysis with the jig :in place. Other smaller 22 systems, such as the DePuy~ GlobalTM Fx System also include a positioning 23 jig. Although the jig of the CrlobalTM Fx System allows for better range of 24 motion analysis than the Tornier~ system; the GlobalTM Fx System still 2s includes a somewhat large positioning jig, which could benefit from being 25 changed to a more low profile system. Thus, an improved system for properly 2~ positioning the stemmed Numeral companent is desired.

i BRIEF SUMMARY OF THE INVE'.~TTION
2 The present invention relates to a set of tools and accessories used 3 fox properly positioning a stemmed Numeral component, and/or a Numeral stem 4 provisional, within a canal in the humerus. The set of tools and accessories s includes one or more fin clamps that are configured to be temporarily attached 6 to a fin on the Numeral component or the provisional; a ruler that is configured to be attached to the arm of the fin clamp, a fixation pin and pin driver s configured to be used with the other tools for marking a position on the g humerus; and one or more sleeves that are configured to slide over the stems of to the Numeral stem provisional to maintain it in the desired position.
More specifically, the present invention. includes a fin clamp for 12 positioning a stemmed Numeral component, or a hvmeral stem provisional, i3 within a humerus during shoulder arthroplasty, where; the fin clamp includes a ~4 head and an arm connected to the head. The head is configured to be seated is between a proximal end of the humerus and a distal side of a collar of the i5 stemmed Numeral component or the Numeral stem provisional, such that the m head separates the proximal end of the hurnerus from the distal side of the is collar by a predetermined distance. Preferably, the head includes an attachment ~9 arrangement to attach the fin clamp to a fin that e.~tends radially outwardly 20 from the stem of the Numeral component or the provisional.
21 The present invention also includes a system of fin clamps for 22 positioning a stemmed Numeral component, or a Numeral stem provisional,.
23 within a humerus during shoulder arthroplasty, where the system of fin clamps 24 includes a .plurality of fin clamps. The system of fin clamps preferably includes 2s at least two fin clamps, and more preferably includes three fin clamps. The i~rst 26 one of the plurality of fin clamps is configured anf. arranged to separate the 2~ proximal end of the right humerus from the distal side of the collar by a first 2s predetermined distance and to separate the proximal end of the left humerus 29 from the distal side of the collar by a second predletermined distance.
'The 3o second one of the plurality of fin clamps is configured and arranged to separate 1 the proximal end of the right humerus from the distal side of the collar by the 2 second predetermined distance and to separate the proximal end of the left 3 humerus from the distal side of the collar by the first; predetermined distance, 4 where the first predetermined distance is different from the second s predetermined distance. The third one of the pharality of fin clamps is 6 configured and arranged to separate the proximal end of either the right humerus or the left humerus from the distal side of the collar by a third s predetermined distance, where the third predetermined distance is different 9 from both the first predetermined distance and the second predetermined distance.
11 The present invention also relates to a method for positioning a ~2 stemmed Numeral component within a humerus during shoulder arthroplasty.
13 The method includes the steps of inserting the stemmed Numeral component, 14 with a fin clamp attached, into a canal located in the humerus at an estimated rs position and seating the Numeral component at an intended position by making 16 contact between the distal side of the fin clamp and the proximal end of the m humerus, whereby the collar of the Numeral component is seated at a certain I s predetermined distance from the proximal end of the hurnerus. If desired, the 19 fin clamp may be attached to the stemmed hume;ral component after the 2o component has been inserted into the Numeral canal, instead of attaching it 21 prior to insertion into the Numeral canal. Preferably, the inserting step and the 22 seating step are each performed twice, once for a hurr~eral stem provisional and 23 once for the stemmed Numeral component. Optionally, the method may include 24 a step of attaching a sleeve upon the stem of the hume;ral stem provisional prior 2s to -the inserting step, where the sleeve helps to secure the Numeral stem 26 provisional in position within the Numeral canal.
22 In addition, the present invention also relates to a method for 2s temporarily securing a Numeral stem provisional within a humerus during 29 shoulder arthroplasty. The methad includes the steps of attaching a sleeve to a 3o stem of the Numeral stem provisional and inserting the Numeral stem i provisional, with the sleeve attached thereto, into a canal located within a 2 proximal portion of the humerus. After determining that the Numeral stem 3 provisional is properly sized and positioned, the Numeral stem provisional and 4 the sleeve are removed, and a permanent Numeral component is implanted in the same location and orientation as the Numeral stem provisional previously 6 removed. In order to mark and recreate the position of the provisional when ~ implanting the permanent Numeral component, a ruler and a fixation pin may be s used.
Also included as part of the present invention is a system of to Numeral stem provisionals and at least one sleeve, which are intended to be n used during shoulder arthroplasty. The system includes a plurality of Numeral 12 stem provisionals each including a stem and at least one sleeve configured to fit 13 upon the stem of each Numeral stem provisional. Tl~e sleeve aids in securely 14 seating the associated humenal stem provisional within a canal located within a Is proximal portion of a humerus.
16 The present invention also relates to a ruler fox use in positioning m a stemmed Numeral component, or a Numeral stem provisional; withird a 1 s humerus during shoulder arthroplasty. The ruler preferably includes a scale 19 with incremental marks indicting distance from a zero point; and a securing 2o assembly for securing the ruler to another device: used for positioning a 21 stemmed Numeral component, or a Numeral stem provisional, within a humerus 22 during shoulder arthroplasty.
23 Finally, the present invention also relates to a system that 24 includes a fixation pin and a driver used for inserting the fixation pin into a 2s bone for marking the orientation of a provisional prosthesis in, order to 2~ duplicate proper orientation for the final prosthesis" The system preferably 2~ includes a fixation pin with a threaded portion near a first end and a portion of 2s non-circular cross-section near a second end thereof; and a driver that includes 29 a first end portion and a second end portion. The first end portion preferably 3o includes an axially extending aperture with a portion thereof that is of a non-I circular cross-section that corresponds to the non-circular cross-section of the 2 fixation pin. The second end portion of the driver is preferably configured to 3 either accept a T-handle (for manual rotation} or to be attached to a drill (for 4 mechanized rotation}.
s BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the present invention are described ~ herein with reference to the drawings wherein:
s Figure 1 is a view of a fractured humerus, with a stemmed 9 Numeral component and head inserted into a :canal within the humerus;
1o Figure 2 is a view showing the fin clamp and a sleeve for ~ 1 positioning a Numeral stem provisional within a canal :in the humerus;
12 Figure 3 is a perspective view of a sleeve that is intended to be 13 used to maintain the pasition of a Numeral stem provisional within the Numeral 14 canal;
Is Figure 4 is a perspective view of one type of fin clamp, shown 16 from the top and front side;
m Figure ~ is a different perspective view of the fin clamp of Figure ~ s 4, shown from the bottom and rear side;
n9 Figure 6 is a top view of the fm clamp of Figure 4;
20 Figure 7 is a front view of the fin clamp. of Figure 4 attached to a 21 Numeral stem provisional, and including a scale to show the zero point;
22 Figure 8 is a view similar to Figure 2, except this figure shows the 23 two version pins used to test the range of motion;
24 Figure 9 is another view similar to Figure, 2, except this figure 2s shows the ruler in place, and the driver being used to insert a fixation pin into 26 the bone;
2~ Figure 10 is a perspective view of the ruler of Figure 9;

1 Figure 11 is a perspective view of the .fixation pin and driver of 2 Figure 9, except instead of including a portion of the drill, this figure includes a 3 T-handle;
Figure 12 is a view of the end of the fixation pin, with an enlarged view of one of the screw threads;
Figure 12A is an enlarged view taken within circle 12A of Figure ~ 12;
s Figure 13 is cut-away view of the end of the driver into which the 9 fixation pin is inserted;
to Figure 14 is a front view of the fin clamp of the earlier figures, n which creates the same predetermined distance whether used for the right 12 humerus or the left humerus;
13 Figure 15 is ac front view of a second fin clamp, which creates la different predetermined disl:ances far the right humerus and the left humerus;
I s and 16 Figure 16 is a front view of a thixd fin clamp, which creates 17 different predetermined distances for the right humerus and the left humerus i s that are reversed from those of the in clamp shown in Figure 15.
19 DETAILED DESCRIPTION OF THE I~1VENTION
20 The present invention relates to a system of components used for 21 properly positioning the stemmed Numeral component of a shoulder prosthesis, z2 and/or to positioning the Numeral stemmed provisional, as well as to the methods of using those positioning components. The system includes one or 24 more fin clamps, version pins, a specially configured ruler, one or more sleeves 2s designed to be attached to the Numeral stemmed provisional, a fixation pin and 26 a driver for the fixation pin.
2~ Figure 1 shows one example of a stemmed Numeral component zs 10 inserted within a humerus that has suffered a classic four-part fracture. In a 29 four part fracture, bone has fractured into the following four parts -- the lesser 1 tuberosity 14, the greater tuberosity 16, the Numeral shaft 18, and the Numeral 2 head (not shown). During shoulder arthroplasty, the stemmed Numeral 3 component 10, including a Numeral head 20 (wlcich may be a separate 4 component or may be integrally formed with the Numeral component), is s implanted into a canal that is naturally found in the Numeral shaft 18 (if necessary, the Numeral canal may be enlarged), and the lesser and greater tuberosities (14 and 16) are refitted and secured around the stemmed Numeral s component 10 in locations as close as possible to their original anatomical 9 positions. It should be noted that although the present specification shows and Io describes only one example of a type of stemmed Numeral component and 11 provisional, it is contemplated that the present invention could also be applied 12 to stemmed Numeral components and provisionals of many different 13 configurations.
14 In order for the shoulder prosthesis to mimic the original range of 1s motion of the shoulder joint, it is very important for all of the components of 16 the prosthesis to be properly positioned. The present invention relates to 1~ positioning the stemmed Numeral component, as well as to positioning a 1g Numeral stem provisional, the stem of which is configured to match the 19 permanent stemmed Numeral component. As known in the art, the Numeral 20 stem provisional is temporarily placed in position in t:he Numeral canal prior to 21 permanently positioning the permanent stemmed Numeral component.
22 Turning now to Figure 2, one example of a Numeral stem 23 provisional 22 is shown inserted into a canal within. a left Numeral shaft 18.
24 Since the provisional itself and the process of enlarging the Numeral canal (if 2s necessary) are not part of this invention, and also since different types of 26 provisionals and several prior art methods of enlarging the Numeral canal are 2~ known, these aspects will riot be discussed in detail, except as necessary for 2s understanding the present invention. Further, for ease of description, the z9 implants, tools and procedures shown and described will normally only be 3o described for use with the left shoulder. However, o:ne of ordinary skill in the art can easily apply and modify, where necessary, the implants, tools and 2 procedures for use with the right shoulder. As can be seen in Figure 2, the 3 Numeral stem provisional 22 in this example includes a stem 24, a collar 26, ~ and four fins that extend radially outwardly of the sl:err -- a medial fm 2~, a s lateral fin 30, an anterior fin 32, and a posterior fin 33 (shown in Figure 1) that 6 is a mirror image of the anterior fin 32. The collar 26 of the provisional 22 has a proximal side 34 and a distal side 36.
s Seated upon the stem 24 is a sleeve 25, which is preferably made 9 of foam or other compressible material. The sleeve :~5 serves to maintain the Io Numeral stem provisional 22 in position during intraoperative assessment of its 1 ~ axial height and version. In other words, because the ;>tem provisional 22 is not ~2 cemented or otherwise rigidly held in place, it may move from the intended i3 position. However, by attaching the sleeve 25 to the stem 24 prior to insertion 14 of both into the canal located within the Numeral shaft 18; the position of the is provisional 22 is maintained. Although the sleeve 25 helps to maintain the 15 provisional 22 in position, the addition of the sleeve 25 to the stem 24 of the m provisional 22 does iiot create such a tight fit that the provisional cannot be i 8 moved at all. Thus, even with the sleeve 25 in place, the position of the 19 provisional 22 can be adjusted, if necessary. However, the sleeve 25 provides a 2o tight enough fit within the Numeral canal to'prevent unintended movement of 2I the provisional 22 within the canal.
22 Turning ~ now to Figure 3, a perspective view of a preferred 23 embodiment of the sleeve 25 is shown. Basically, the sleeve 25 is cylindrical in 24 shape; and is preferably made of foam or other similar material.
Preferably, the 2s sleeve 25 is manufactured by stamping multiple hollow cylindrical-shaped 26 sleeves from a flat sheet of foam (i.e., by axialldr stamping the sleeves).
2~ Alternatively, the sleeve 2S may be manufactured by rolling a flat, rectangular 2s piece of foam into the hollow cylindrical shape shown, with the rolled edges 29 being glued or otherwise affixed together along an axial line 39. Other methods 30 of fabrication are also contemplated, such as injection molding, in which case 1 the cylindrical shape can be directly formed. In order to provide better gripping 2 upon the stem, as well as to make the sleeve suitable for use with stems of 3 different diameters, four slits 40 are provided to run axially along the sleeve's 4. inner periphery 42. The slits 40 are preferably between 1 mrn and 2mm in s depth, although other depths are also contemplated. Although four slits are 6 shown in this example, a different number of slits may also be used, or the slits may be omitted entirely, if desired.
s The sleeve 25 also preferably includes a tether 44 that is attached 9 via a hole 46 formed within a sidewall of the sleeve 25. In most cases, the 1o tether will not be used because the sleeve 25 will remain attached to the stem i 1 24 of the provisional 22 when the provisional is removed from the Numeral 12 canal. However, if the sleeve somehow slips off of the provisional 22; 'the 13 tether 44 may be used to pull the sleeve 25 out of the Numeral canal. Thus, the 14 tether should be long enough to extend out of the Numeral canal, with sufficient Is length for gripping. For example, in the preferred embodiment, the tether 16 extends from the hole 46 about eight inches. Of course, the length of the tether m may be varied to be longer or horter~ if desired.
1 s The tether 44 is preferably made of suture or other strong thread, 19 and is preferably a looped thread that has a knot 48 near the looped end 49. To 2o secure the tether 44 to the sleeve 25, the looped end 49 is passed through the-2i hole 46 until it extends out through the end of the sleeve 25. Then the free end 22 50 and the knot 48 are passed through the looped en.d 49, and the free end is 23 pulled to tighten the tether. Of course, other methods of attaching the tether to 24 the sleeve are also contemplated:
25 Preferably, the sleeve 25 will be available in a variety of sizes 26 because there are a variety of sizes of Numeral stem provisionals. Thus, for 2~ example, there may be a different sized sleeve for each different size of 2s Numeral stem provisional. ~lowever, in order to redu<;e the number of different 29 sizes of sleeves that need to be stocked, each sleeve can preferably be 3o configured to be used with several differently sized provisionals. For example, i if humeral stem provisionals are available in thirteen different sizes, only four 2 different sizes of sleeves are preferably needed, with each sleeve being able to 3 fit three or four differently sized provisionals. The following chart provides a 4 helpful example of how the sleeves can be sized:
INTERIOR

EXTERIOR INTERIOR DIAMETER OF STEM

DIAMETER OF DIAMETER OF SLEE~dE DIAMETER OF

SLEEVE SLEEVE (INCLUI?ING PROVISIONAL

TWO SLITS) I2 mm ~ mm 8 mrn 6 mm - 8 mm 16 mm ~ mm 11 mm 9 mm - 11 mm 20 mm 12 mm 15 mm 12 tnm - 14 mm 24 mm I 6 mm 20 mm ~ 15 mm - 18 mm s As indicated in the chart above for thirteen different provisional 6 sizes with stem diameters between 6mm and l8mm (in lmm increments), only four different sleeves are needed because a 6mm interior diameter sleeve fits 8 provisionals with stems of diameters between 6mm and 8mm; a 9mm interior 9 diameter sleeve fits stems between 9mm and l lmm; a l2mrri interior diameter 1 o sleeve fits stems between l2mm and l4mm, and ~. 16mm sleeve fits stems i 1 between 15 and 18mm. One reason that the sleeves can be used with 12 provisionals of different sizes is that the four slits 40 allow the inner diameter 13 of the sleeves to slightly adjust to accommodate the dlifferent diaW eter stems of t4 provisionals of different si~;es. As shown in the chart, a sleeve with a l2mm Is exterior diameter has an interior diameter of 6mm (in the area without any m slits), but it has an interior diameter of 8mm in the area with two of the slits m because each slit is I mm in depth (thereby the diarr~eter is increased by 2mm i s because the two slits face each other). Likewise, the slits in the l6mm exterior 1 diameter sleeve are also each preferably 1 mm in depth. The slits in the 20mm 2 exterior diameter sleeve are each preferably l .5mm in depth, and the slits in the 3 24mm exterior diameter shaft are each preferably 2mm in depth. Additionally, 4 the axial length of all of the sleeves can be the same:. For example, the axial s length of each sleeve is preferably between 20 and 40mm. Of course, the 6 dimensions mentioned above, and in other parts of thus specification, are only ~ examples of suitable dimensions, and other appropriate dimensions can be s determined by those of ordinary skill in the art.
For ease of identification to distinguish the differently sized to sleeves from one another, each of the sizes can be made of a different color, if n desired. Accordingly, since there are four different sizes of sleeves in the 12 example above, four different colors of foam would be used to produce the 13 sleeves. However, since the most likely instances of confusion arise between 14 sleeves that are only slightly larger or slightly smaller than each other, it may Is only be necessary to use two different colors, alternating between the two 16 colors as the sleeves increase in size. For example for a set of four sleeves of 7 exterior diameters of l2mm; l6mm, 20mm and 24m.m, the l2mm and 20mm 1 s sleeves could be of a first color, and the l6mm and 24 mm sleeves could be of a 9 second color that is different from the first color. Such a system works because 2o it is unlikely that someone would be confused between the 12 and 20mm 2i sleeves or between the 16 and 24mm sleeves. By only using two colors instead 22 of four, manufacturing costs are reduced.
23 Turning back to Figure 2, another important aspect of the present 24 invention will be described -- fin clamp 60. Fin clamp 60 is preferably made zs of stainless steel or other metal, but other materials, such as plastic, may also be 26 used. As described more fully bel~w, the fin clamp 60 is used to properly 2~ position the stemmed Numeral component (and the Numeral stem provisional) 2s with regard to both its axial height and its retroversion. Axial height 29 positioning will be discussed first. Figure '7 shows one example of a fin clamp 30 60 attached to a stemmed Numeral component 10, which is shown alongside a ~ measurement scale. In the preferred embodiment, the zero point of the scale is 2 taken as the point where the center axis of the stem 24 meets the distal side 36 3 of the collar 26. This zero pointy and the rest of the numbering scale, is the ~. same one currently used on other tools and templates in the Bigliani/Flatow~
Shoulder Arthroplasty System, manufactured by Zi.mmer Ine. of Warsaw, 6 Indiana. However, it is not necessary to use the same scale as the 7 Bigliani/Flatow~ System, and other measurement sy;~tems and/or zero points s may be used instead of those described.
Analysis has shown that in most fracture situations, the distal side to 36 of the provisional's collar 26 should be spaced a certain distance from the ~ i proximal surface 38 of the Numeral shaft 18. (Of course, since the relevant 12 portions of the provisional are sized and shaped identically to those of the 13 permanent stemmed Numeral component, the collar of the permanent 4. component, as well as the other portions of the permanent component, should ~s be positioned identically to those of the provisional.) More specifically, in 6 most average sized adults, it has been found that in four-part fracture scenarios, 7 the fractured joint is best rebuilt by positioning the stemmed Numeral is component so that there is l8mm of space separating the distal. side 34 of the 9 collar 26 (at the anterior fin) from the proximal surface 38 of the Numeral shaft 20 18. However, in certain cases, the appropriate spacing is either slightly Less or 21 slightly greater. than l8mm. Far example, certain situations requixe a lSxnm 22 space and other cases require 2lmm of space. Accordingly, as described 23 below, the preferred embodiment of the invention 'includes a set of fin clamps 24 that are configured to provide spacing of the following predetermined 2s distances: lSmm, l8mm, and 2lmm, in order to obtain the proper spacing in a 25 variety of different situations. However, the invention is not limited to these 27 sizes.
2s First, fin clamp 6d, which provides l8mm spacing, will be 29 described. The fm clamp 60 is configured to be attached to the anterior fm 0 of the Numeral stem provisional 22, as shown in the exploded view of Figure 2.

I Likewise, because the stemmed Numeral component 10 has essentially the same 2 configuration as the provisional 22, the fin clamp 60 is also configured to be 3 attached to the anterior f n of the stemmed Numeral component in the same a. manner as attached to the provisional.
As shown in Figures 2, 4, 5 and 6, the fin clamp 60 includes a 5 head 62 and an arm 64. The head 62 is configured to be seated upon the ~ anterior fin 32 so that the head 62 is positioned between the proximal end s surface 38 of the humerus 18 and the distal side 36 of the collar 26. In this 9 embodiment, the head 62 separates the proximal end surface 3 8 of the humerus to from the distal side 36 of the collar 2b by l8mm. This embodiment of the fin n clamp 60 is called the "universal" fin clamp because it can be used in most 12 situations and because it can be used on either the left humerus (as shown in 3 Figure 2) or on the right humerus, with the separation distance for each side 14 being the same (l8mm). Other embodiments of the fin clamp, which will be is described below, are also configured to be used on either the left humerus or t6 the right humerus, but in these other embodiments, the separation distances are m not the same for both sides.
t8 The head 62 includes a channel 66 (best seen in Figure 6) that is 19 configured to accept the anterior fin 32 of both the hmmeral stem provisional 22 2o and the stemmed Numeral component 10. Preferably, the channel 66 is ~yust 21 slightly deeper than-the radial length of the anterior fi.n 32, and is defined from 22 side-to-side between an endblock 67 and a wall 69. An attachment 23 arrangement that includes one or more setscrews is provided in order to attach 24 the fin clamp 60 to the anterior fin 32: More specifically; the preferred 25 embodiment includes two threaded holes 68, 70 (best shown in Figure S) that 26 extend through the wall 69, and two setscrews 72, 74, with one setscrew being 2~ seated in each threaded hole. If desired, only one setscrew may be provided for 2s both holes, in which case the user simply inserts the single setscrew into the 29 appropriate hole. Preferably, the setscrews include sharp pointed tips for 3o providing more secure attachment to the fin.

In order to attach the fin clamp 60 to the anterior fin 32, one of 2 the setscrews (72 or 74) is tightened so that it extends through the wall 69 and 3 makes contact with fin 32. Preferably, whichever setscrew is positioned on the a proximal side will be tightened because easier access is provided for that one.
s Thus, if the fin clamp 60 is being used during left shoulder arthroplasty, 6 setscrew 74 is the proximal setscrew and it will be tightened, and if it is being used during right shoulder arthroplasty, setscrew 72 i;9 the proximal one, and it s will be tightened.
The fin clamp's head 62 includes two angled surfaces 76 and 78, to as most clearly shown in Figures 2 and 4, which are symmetric to each other i t and which correspond to the angle of the distal side 36 of the collar 26 of the 12 Numeral stem provisional 22 and the stemmed Numeral component 10 (shown 13 in Figure 7). Flat surfaces 80 and 82 are also included adjacent to the angled 14 surfaces 76 and 78, respectively. These surfaces are configured in this manner Is so that the surgeon can easily tell that the fin clamp 60 is properly positioned n6 (and therefore the provisional 22 or the Numeral component 10 is also properly 1~ positioned) by noting when one of the angled surfaces (76 or 78) contacts the I8 distal side 36 of the callar 26 and the opposite flat surface (either 82 or 80) ~9 contacts the proximal surface 38 of the Numeral shaft. More specific~.lly, 2o during left shoulder arthroplasty, proper axial positioning has been obtained 2r when angled surface 78 contacts the distal side 36 of the collar 26 and the flat 22 surface 82 contacts the proximal surface 3 8 of the Numeral shaft. If the 23 universal fin clamp 60 is positioned in this manner, the desired l8:mm z4 separation is provided. For ease of description, the invention is being described 2s and shown as applied to a left Numeral stem provisional only (as well as to a 26 left stemmed Numeral component only). However, the universal fin clamf> 60 2~ can also be used with a right provisional or right hurneral component if the. fm 2s clamp is flipped so that the opposite angled surface is the one making contact 29 with the collar of the provisional (or Numeral component).

1 In order to facilitate obtaining the proper orientation of the fin 2 clamp 60, markings indical:ing the proper orientation of the fin clamp are 3 preferably provided. Different markings need to indicate the proper orientation 4 for use during left shoulder arthroplasty and during right shoulder arthroplasty, s because the orientation of the fin clamp is not the same for each side. One 6 example of such markings is shown in Figure 7, which includes the markings L 18 and R18. These markings indicate that this fin clamp provides 18mm s separation distance, and they also show the proper orientations of the fin clamp 9 when used on either the left shoulder or the right shoulder. More specifically, to in this example, when the .fin clamp is used during an operation on the heft n shoulder, the designation L18 is upright (as shown in Figure 7), and when used 12 during an operation on the right shoulder, the designation Rl8 is upright.
Of 1~ course, other types of markings may alsa be used; or the markings may be ~4 omitted entirely, if desired.
is Turning now to Figures 15 and 16, two additional embodiments 16 of the fin clamp will be described. The fin clamps of Figures 15 and 16 are m used for creating predetermined separation distances other than the l8mm Is distance described above with regard to fin clamp ~0. Figure 15 shows fin 19 clamp 60' and Figure 16 shows fin clamp 60". Figure ~ 14, which shows the 2o first embodiment, fin clamp 60, has been provided i~a order to easily compare 21 the configurations of fin clamps 60' and 60'' with-that of fin clamp 60.
Fin 22 clamps 60' and 60" axe essentially the same as fin clamp 60, except that they 23 provide different separation distances than fin clamp 60. Additionally, fin 24 clamps 60' and 60" are not symmetric about their respective central axis, as fin 2s clamp 60 is.
26 More specifically, fin clamp 60' of Figure 15 is configured to 2~ provide a separation distance of l5mm when used during left shoulder 2s arthroplasty, as designated by the marking "L15," and to provide a separation 29 distance of 2lmm when used during right shoulder arthroplasty, as designated by the marking "R21" (which is nearly upside-down i.n Figure 15). As with the t universal fin clamp 60, which has designations L18 and R18, the surgeon can 2 tell which direction the clamp should be oriented and the separation distance 3 created by the clamp by looking at the designations L 15 and R21. More 4 specifically, with fin clamp 60', when this fin clamp is used during an operation s on the left shoulder; the designation L 1 S should he upright (and a 1 Smm 6 separation will be provided), and when used during an operation on the right shoulder, the designation R21 should be upright (andl a 2lmm separation will s be provided).
Fin clamp 6(1" of Figure 16 merely provides the opposite - to configuration to that of clamp 60' of .Figure 15. 'thus, fin clamp 60"
c;an i 1 provide a 2lmm separation distance during left shoulder arthroplasty, and it can ~2 provide a l5mm separation during right shoulder arthroplasty. More 13 specifically, with fin clamp 60", when this fin clamp is used during an 14 operation on the Ieft shoulder, the designation L21 should be upright (and a is 2lmm separation will be provided), and when used during an operation on the 6 right shoulder, he designateon RI S should be upright: (and a l Smm separation 1~ will be provided).
a s In order to allow the surgeon to be able to accommodate 19 situations where any one of the three different separation distances (lSrrun, 20 l8mm and 2lmm) is to be provided, a system, or kit, that includes several 21 different fin clamps should be provided. More specifically, in the preferred 22 embodiment of the kit or system, three different fin clamps are provided --fin 23 clamp 60, fin clamp 60' and fin clamp 60". Accordin.gly, with the kit, the most 24 commonly-desired separation distances can reliably be: obtained.
2s As mentioned above, in addition to obtaining the correct a~~ial 26 spacing, the present invention also provides a way to set the proper retroversion 2~ of the humeral stem provisional and the stemmed hurrreral component.
Turning 2s now to Figure 8, the humeral stem provisional 22 is shown seated within a 29 canal in the left humerus 12, and the fin clamp 60 has been secured to the o anterior fin by tightening the setscrew 74.

I The first step for obtaining the proper retroversion of the 2 provisional 22 and/or the Numeral component 10 relates to aligning the arm 3 with respect to the approximate position of the bicipital groove in an intact 4 humerus (Figure 1 shows a bicipital groove 92), if clear evidence of the groove s is still available. If the bicipital groove cannot be located, the surgeon may 6 simply estimate its position, and align arm 64 with that estimation, or slightly 7 posterior to the estimated position of the groove.
s Figure 6 shows that the arm angle is preferably 55 degrees from g the anterior fin 32 (and ~5 degrees from the axial stem of the Numeral to component 10 and the provisional 22, when the fin clamp is attached thereto).
t 1 Designing the arm 64 of the fin clamp 60 to be at the 55 degree angle to align 12 with the bicipital groove has several advantages. The fracture line between the ~3 lesser tuberosity 14 and the greater tuberosity 16 typically occurs either in line 14 with, or slightly posterior to, the bicipital groove 92, as shown in the Figure 1 is example. Because the 55 degree angle aligns the arrry64 of the fin clamp with 16 this fracture line, the arm 64 does not interfere with the surgeon's task of m reorienting the tuberosities to confirm the position of the provisional 22 and/or I g the Numeral component 10 while the fin clamp is attached to the provisional or 19 the Numeral component. In addition, with the arrm 64 of the fin clamp 2o configured at this angle, the arm does not interfere with a range of motion 2r analysis. ..
22 The second step for obtaining the proper retroversion involves the 23 use of two version pins. In Figure 8, two version pins 84 and 86 are she>wn 24 inserted into two version pin holes 88, 90; respectively (the version pin holes -zs are also shown in Figure 4, without the version pins imser~ed therein).
Turning 26 now to Figure 6, version pin hole 88 is set to be 20 degrees from channel 2~ (which sets it at 20 degrees from the anterior fin 32 and 20 degrees from the 2s axial stem of the Numeral component 10 and the provisional 22, when the fin 29 clamp is attached thereto). In a similar manner, version pin hole 90 is set to be 30 40 degrees from channel 66 (and 40 degrees from the anterior fin and the axial 1 stem of the numeral component 10 and the provisional 22, when the fin clamp 2 is attached thereto). When the two version pins 84 and 86 are seated within 'the 3 appropriate version pin holes 88 and 90, as shown in Figure 8, the retroversion 4 of the provisional 22 or the numeral component 10 can be tested by extending s the patient's arm to make sure that the patient's forearm is centered between the .
version pins 88 and 90. To avoid confusion regarding the use of version iain ~ holes 88 and 90, it is desirable to have them marked with degree indications s "20" and "40," as shown in Figure 4. However, such markings are . not 9 required. It should be noted that the 20 and 40 degree orientations of the - - version pins and the 55 degree stem angle shown and described are intended to 11 be used for guidance to obtain proper retroversion. In certain situations, proper 12 retroversion, as discovered during a range of motion analysis, will differ from 13 these guidelines.
14 Once the proper axial height and the version of the provisional 22 1s has been established, and the provisional is located in the desired position, it is 16 useful to mark that position to facilitate the placement of the permanent 1~ stemmed numeral component 10 into the exact same position. The present 1 s invention includes the following tools for marking the position -- a specially 19 configured ruler that can be attached to the arm of the fin clamp and a fixation o pin and pin driver for temporarily inserting the pin inti~ the humerus at a desired -21 location along the scale of the ruler.
22 , Figure 9 shows one example of a specially configured ruler 94 23 attached to the arm 64 of fin clamp 60, with fixation pin 96 being inserted into 24 a slot (or elongated hole) 95 in the ruler via a pin driver 98 that is attached to a 2s rotary drill 100. Preferably, the ruler 94, the fixation pin 96 and the driver 98 26 axe all made of stainless steel, or other metal, although other materials are also 2~ contemplated.
2s Briefly, in order to mark the location of the provisional, the ruler 29 94 is attached to the fin clamp's arm 64, and the fixation pin 96 is temporarily 3o driven into the humerus 18 at a position within the ruler's slot 95, and the 1 position of the pin with respect to the ruler is noted. Then, the provisional 22, 2 the fin clamp 60 and the ruler 94 are removed, but the fixation pin 96 remains 3 in place in the humerus. The permanent stemmed Numeral component is 4 inserted into the humerus, and the fin clamp 60 and ruler 94 are attached s thereto, as they were attached to the provisional. The: position of the assembly 6 of the permanent stemmed Numeral component, the fin clamp and the ruler is adjusted until the fixation pin is positioned at the same spot within the slot on s the ruler that was previously noted. Thus, by using the fin clamp, the ruler and 9 the fixation pin (and pin driver) -- the version and height of the provisional can to be been duplicated for the permanent Numeral component.
1 ~ Details of the preferred embodiment of the ruler 94, the fixation 12 pin 96 and the pin driver 98 will be described next, while making reference to 13 Figures 9-13. Figure 10 shows a perspective view of the preferred embodiment m of the ruler 94, which includes a securing assembly 1.02 and a main body 1.04 ns that has a scale 106 and the slot 95 mentioned above. The securing assembly 16 102, which is used to secure the ruler 94 to the arm 64 of the fin clamp 60 (as m shown in Figure 9), preferably includes an opening 108, which allows the ri:~ler 1 s to be slid upon the arm 64 of the fin clamp 60. Preferably, the opening 108 is 19 large enough to allow the arm 64 to slide through with ease, but not so large 2o that the ruler is free to rotate about the arm. It is also desirable to 'configure the 21 opening 108 with flat upper and lower surfaces 112, 114, which, in 22 combination with the flat upper and lower surfaces 116, l 18 of the fin clamp's 23 arm 64 (Figure 4), also prevent the ruler 94 from unduly rotating on the arm 64.
24 The securing assembly 102 also includes a setscrew 110 that extends into a 2s threaded hole that goes into opening 108. By tightening the setscrew 110, the 26 ruler 94 can be secured upon the arm 64. Preferably, 'the setscrew 110 includes 2~ a flat bottom, which provides better lateral stability for the ruler when i1; is 2s attached to the arm. Although only a setscrew-based securing assembly 102 has 29 been shown and described, other mechanisms for securing the ruler to the arm 3o are also contemplated:

1 As can be seen in Figure 10, the scale 106 includes a plurality of 2 incremental marks. Although not shown, periodic numerals may also be added 3 for ease of reference. It should be noted that the scale 106 is preferably based 4 on the same scale with the same zero paint used for the fin clamp 60, which s was shown and described while referring to Figure i'. Thus, in this preferred 6 embodiment, the upper incremental mark 120 on the ruler 94 would be designated as l5mm (and not zero) because when the ruler is properly secured s upon the arm 64 of the fin clamp 60, the incremental mark 120 is located l5mm 9 from the zero point on the numeral stem provisional (or the stemmed Numeral io component). Optionally, a series -of peripheral ,grooves 122 may also be 11 provided on each side of the main body 104 at regular increments (such. as 12 every l Omm) in order to facilitate reading the scale.
13 Figure 11 shows an example of the preferred embodiment of the 14 pin 96 and the pin driver 98, as well as a T-handle 124 that can be attached to ~s the pin driver for manually rotating the pin. If desired, the T-handle 124 can be 16 used in place of the rotary drill 100 mentioned earlier, if manual insertion of the 1~ pin is desired. The end of the pin driver 98 is preferably configured to accept is either the T-handle 24 or the drill 100. In order to transfer rotation from the; T-t9 handle 124 or the drill 100 to the pin driver 98, one end 126 of the driver 2o preferably includes one or more flat'surfaces 128, and forms the male portion of 21 a male/female connection, where the female portion is found on end I30 -of the 22 T-handle 124 (of the drill 10), the interior periphery of which is shaped to 23 correspond to end 126 of the pin driver 98, and included the same number of 24 flat surfaces as found on the driver. In the preferred embodiment, there are:
2s three flat surfaces 128 on the male portion formed on the driver.
Accordingly, 26 there would also be three flat surfaces ~n the female portion formed on the T-2~ handle or drill. ~f course, cross-sectional shapes other than those described 2s can also be used to transfer rotation from the T-handle (or drill) to the pin 29 driver 98.

The other end of the driver 98, end 132, should also include 2 means for transferring rotary motion, but this time the rotary motion is being transferred from the pin driver 98 to the pin 96. Accordingly, the pin driver and the pin should include mating malelfemale portions of corresponding non s circular cross-sections. In the preferred embodiment shown in Figure 11, a flat portion 134 is used to create a non-circular cross-section on the pin 96, which defines the male portion of the connection. As best shown in Figure 13, a s corresponding flat portion 136 is created on the inner periphery of end 132 of the driver 98, thereby creating a female portion with a corresponding non-t.o circular cross-section. Although only one type of n.on-circular cross-sectional 1 i shape is being shown and described, other non-circular cross-sectional shapes 12 may also be used, as long as they allow the transfer of rotary motion between 13 the driver and the pin.
14 For ease of manufacture, the flat portion I36 of the driver 98 may Is be formed during a separate process after aperture 138 has been drilled. In the 16 preferred embodiment, flat portion I36 is formed by depositing material, such m as the same metal used for driver 98, into a cavity 140 formed near end 132 of i s the driver. In order to catch and shape the material, a mold is inserted into i9 aperture 138 to create the desired shape of the flat portion 136. Once the 2o material placed into cavity 140 has dried, the mold is removed and the.
outer -21- periphery can be machined to create a smooth outer periphery. Drilling a .
.
22 circular aperture 138 and inserting a plug-of material in a cavity 140 is easier, 23 and less costly, than directly attempting to machine an aperture with a flat 24 surface.
2s To inform the surgeon of the location of the flat surface 136 on 26 the driver 98 so that the flat surface 134 of the pin can be properly oriented to 2~ contact the flat surface 13G when the pin is inserted into the driver, a line 140 or 2s other type of mark may be engraved or otherwise made on the outer periphery 29 of end 132 of the driver 98. In order to more tightly secure the pin 96 within the driver 98, a C-ring 142 is preferably seated within a channel 144, as shown 1 in Figure 13. The channel 144 is preferably formed in an area of the aperture 2 138, of circular cross-section, that is between the location of the flat surface 3 134 and end 132.
Turning now to Figures 11, 12, and 12A, the pointed end 146 of s the pin 96 will be discussed. As mentioned earlier, the pin 196 is temporarily 6 inserted into the humerus after the Numeral stem provisional has been properly positioned, in order to facilitate re-creation of that position for the stemmed s Numeral component. Accordingly, the pointed end 146 of the pin must be 9 configured so that it can be easily .inserted/removed to/from the bone, and also 1o so that when it is inserted into the :bone, it remains securely in position. The r ~ preferred embodiment of the pointed end includes a knife edge tip 148 and a 12 sharpened threaded portion 150.
~3 The knife edge tip 148 is used for cutting the initial pathway for 14 the remainder of end 146 of the pin 96 being inserted into the bone. The knife is edge tip 148 is preferably generally flat, and generally triangular-shaped.
The 16 two edges that converge to form the tip are preferably sharpened, so that the tip m can be easily inserted into the bone when the pin is rotated:
i s Figure 12A shows a magnified section of the sharpened threaded 19 portion 150, taken from within circle 12A of Figure 1:2, which shows a trough 20 152 between two sections ef the thread in order to illustrate the preferred 21 confi-guration of the threaded portion. More specifically, Figure 12A shows 22 how a trailing edge portion 154 of the thread continues into a trough 152 and 23 how it further continues into the leading edge portion 156 of the next section: of 24 thread. As shown in the figure, the leading edge :portions 156 are sloped, 2s preferably at approximately 35 degrees, to facilitate a~utting into the bone. In 26 contrast, the trailing edge portions 154 are essentially normal to the axis of the 2~ pin 96 (or they may be slightly sloped at approximately 3 degrees), which helps 2s to prevent the pin from becoming dislodged from the bone.
29 To provide for better understanding of the present invention, the o method of using the tools described above will be summarized, without the detailed descriptions of the tools themselves already provided, while referring 2 primarily to Figures 2, 8 and 9. After the Numeral canal has been prepared and 3 the proper size of stemmed Numeral component has been selected, a Numeral 4 stem provisional 22 of the same size as the Numeral component is selected, an s appropriately sized sleeve 25 is attached to the provisional's stem 24, and the desired fin clamp is attached to the provisional. The provisi~nal 22 (with a~
fin clamp and a sleeve attached) is inserted into the Numeral canal, and the selected fin clamp (60, 60' or 60") is used to properly position the provisional within 9 the Numeral canal. Although the appropriate fm clamp is preferably attached to io the provisional-prior to its insertion into the canal, the fin clamp may also be i 1 attached to the provisional after insertion into the. canal, if desired.
Attachment i2 of the fin clamp to the provisional is accomplished by tightening the setscrew 13 located on the proximal side (72 ar 74; 72' or 74'; 72" or 74"). The appropriate fin clamp is selected depending upon whether the operation relates to the left is shoulder or the right shoulder, and whether the desired separation distance m between the proximal end of the humerus 38 and the distal side 36 of the collar m 26 is intended to be l ~mm; l8min or 2lmm. Once the appropriate fin clamp t s (60, 60' or 60 ") has been selected, the channel 66 is seated on the anterior fm 3 19 of the provisional 22, as shown in Figure 8.
2o After the provisional (with f n clamp and sleeve attached) has 21 been inserted into the Numeral canal, it is rotated so-that the fin clamp's arm 64 22 is either aligned with, or slightly posterior of, the bicipital groove 92 (Figure I j.
23 The axial position of the provisional 22 is adjusted by maintaining the 24 appropriate angled surface (76 or 78; 76' or 78'; 76'' or 78") flush with the 2s distal side 36 of the collax 26, while the appropriate flat surface (82 or 80; 82' 26 or 80'; 82" or 80") is made to be approximately flush with the proximal 2~ surface 3 8 of the Numeral shaft.
28 In order to estimate the proper retroversion of the provisional, 29 version pins 84 and 86 (Figure 8) are. inserted into version pin holes 88 and 90, 3o and the patient's arm is extended so that the forearm sits between the version 1 pins. A range of motion analysis is performed. .Any necessary adjustments to 2 the location of the provisional are then made. The version pins 84 and 86 are 3 then removed from the version pin holes 88 and 90, and the ruler 94 is attached to the arm 64 of the fin clamp; as shown in Figure 9, by tightening the setscrew s 110.
To mark the position of the provisional 22 before it is removed from the Numeral canal, pin 96 is. driven into the bone by being rotated, either manually or with a drill, in a location within the slot 95 of the ruler. The position of the pin within the slot is noted so that it can be recreated when the 1 o stemmed Numeral component is being positioned.
1 ~ Next, the Numeral stem provisional 22, along with the fin clamp 12 and ruler, are removed. The open-ended slot 95 on the ruler 94 permits the 13 ruler to be lifted from the area without disturbing t~~e location of the pin 96.
la. The stemmed Numeral component 10 is then inserted into the Numeral canal in is the position that the provisional previously occupied. The fin clamp is attached 1 ~ to the Numeral stem component, and the axial location and retroversion are m confirmed by inserting the version pins 84 and 86 and by making any necessary 1s adjustments so that the forearm is between the pins: As an additional check on the position of the Numeral component, the ruler 94 is attached to the fm 2o clamp's arm 64; and the position of the alignment pin 96 with respect to the 21 ruler is compared to the position noted earlier. Any necessary adjustments are 22 made. Once the proper position of the stemmed Numeral component has been 23 obtained, it is cemented into place in the conventional manner, and the bone 24 fragments are refitted using any one of the desired conventional techniques:
2s The operation is then continued to completion using any desired technique.
26 While various embodiments of the present invention have been 2~ shown and described, it should be understood that other modifications, 2s substitutions and alternatives may be apparent to one of ordinary skill in the art.
29 Such modifications, substitutions and alternatives can be made without 1 departing from the spirit and scope of the invention, which should be 2 determined from the appended claims.
3 Various features of the invention are set forth in the appended claims.

Claims (41)

1. A fin clamp for positioning a stemmed humeral component, or a humeral stem provisional, within a humerus during shoulder arthroplasty, said fin clamp comprising:
a head that is configured to be seated between a proximal end of the humerus and a distal side of a collar of the stemmed humeral component or the humeral stem provisional, wherein said head separates the proximal end of the humerus from the distal side of the collar by a predetermined distance;
and an arm connected to said head.

2. The fin clamp according to Claim 1, wherein said head includes an attachment arrangement to attach said fin clamp to the stemmed humeral component or the humeral stem provisional.

3. The fin clamp according to Claim 2, wherein said attachment arrangement attaches said fin clamp to a fin extending radially outwardly from a stem of the stemmed humeral component or from a stem of the humeral stem provisional.

4. The fin clamp according to Claim 2, wherein said attachment arrangement includes at least one threaded hole formed within said head and at least one setscrew configured to fit within said threaded hole.

5. The fin clamp according to Claim 2, wherein said attachment arrangement includes a pair of threaded holes formed within said head and at least one setscrew configured to fit within both of said threaded holes, whereby one threaded hole is located on each side of said arm.

6. The fin clamp according to Claim 1, wherein said head includes a plurality of apertures extending therethrough, wherein said apertures are configured and arranged for receiving a plurality of version pins intended to gauge the retroversion of either the humeral stem provisional or the stemmed humeral component.

7. The fin clamp according to Claim 1, wherein said head is configured and arranged to separate the proximal end of the humerus from the distal side of the collar by a first predetermined distance when oriented in the first position with respect to the humerus and by a second predetermined distance when oriented in a second position with respect to the humerus, where said first predetermined distance is different from said second predetermined distance.

8. The fin clamp according to Claim 7, wherein said first position provides said first predetermined distance for use with a left humerus and said second position provides said second predetermined distance for use with a right humerus.

9. The fin clamp according to Claim 1, further comprising:
a channel formed in said head, where said channel is configured and arranged to envelope a fin extending radially outwardly from a stem of the stemmed humeral component or from a stem of the humeral stem provisional;
and wherein the angle defined between a line normal to the length of said channel and a central axis of said arm is approximately 55 degrees.

10. A system of fin clamps for positioning a stemmed humeral component, or a humeral stem provisional, within a humerus during shoulder arthroplasty, said system of fin clamps comprising:
a plurality of fin clamps, where each fin clamp includes:
ahead that is configured to be seated between a proximal end of the humerus and a distal side of a collar of the stemmed humeral component or the humeral stem provisional, wherein said head separates the proximal end of the humerus from the distal side of the collar by a predetermined distance;
and an arm connected to said head.

11. The system of fin clamps according to Claim 10, wherein each of said plurality of fin clamps is configured and arranged for use with both a right humerus and a left humerus.

12. The system of fin clamps according to Claim 11, wherein:
a first one of said plurality of fin clamps is configured and arranged to separate the proximal end of the right humerus from the distal side of the collar by a first predetermined distance and to separate the proximal end of the left humerus from the distal side of the collar by a second predetermined distance; and a second one of said plurality of fin clamps is configured and arranged to separate the proximal end of the right humerus from the distal side of the collar by the second predetermined distance and to separate the proximal end of the left humerus from the distal side of the collar by the first predetermined distance, wherein the first predetermined distance is different from the second predetermined distance.

13. The system of fin clamps according to Claim 12, wherein:
a third one of said plurality of fin clamps is configured and arranged to separate the proximal end of either the right humerus or the left humerus from the distal side of the collar by a third predetermined distance, where the third predetermined distance is different from both the first predetermined distance and the second predetermined distance.

14. The system of fin clamps according to Claim 10, wherein:
a first one of said plurality of fin clamps is configured and arranged to separate the proximal end of the humerus from the distal side of the collar by a first predetermined distance; and a second one of said plurality of fin clamps is configured and arranged to separate the proximal end of the humerus from the distal side of the collar by a second predetermined distance, which is different from said first predetermined distance.

15. A method of positioning a stemmed humeral component within a humerus during shoulder arthroplasty, said method comprising the steps of:
attaching a fin clamp to the stemmed humeral component such that the fin clamp is positioned distal of a distal side of a collar of the stemmed humeral component;
inserting the stemmed humeral component into a humeral canal at an estimated position; and seating the humeral component at an intended position by making contact between the distal side of the fin clamp and the proximal end of the humerus, whereby the collar of the humeral component is seated at a certain predetermined distance from the proximal end of the humerus.

16. The method according to Claim 15, wherein the fin clamp is attached to the stemmed humeral component after inserting the stemmed humeral component into the humeral canal.

17. The method according to Claim 15, wherein said attaching step, said inserting step, and said seating step are each performed twice, once for a humeral stem provisional and once for the stemmed humeral component.

18. The method according to Claim 17, further comprising the step of attaching a sleeve upon the stem of the humeral stem provisional prior to said inserting step, wherein said sleeve helps to secure the humeral stem provisional in position within the humeral canal.

19. The method according to Claim 15, wherein during said step of inserting the stemmed humeral component at an estimated position, he approximate position of the bicipital groove of the humerus, if intact, is used as a reference for aligning an arm of the fin clamp.

20. The method according to Claim 15, further comprising the step of inserting version pins into designated holes in the fin clamp for establishing retroversion of the stemmed humeral component.

21. The method according to Claim 15, further comprising the step of performing a range of motion analysis upon the joint with the stemmed humeral component seated within the humeral canal and fin clamp attached to the stemmed humeral component.

22. The method according to Claim 15, further comprising the step of attaching a ruler to the fin clamp, while the fin clamp is attached to the stemmed humeral component, for determining an axial position of the humeral component.

23. The method according to Claim 22, further comprising the following steps, which are performed prior to said steps of attaching, inserting and seating the humeral component:
attaching the fin clamp to the humeral stem provisional such that the fin clamp is positioned distal of a distal side of a collar of the humeral stem provisional;
inserting a humeral stem provisional into the humeral canal at an estimated position;
seating the humeral stem provisional at the intended position by making contact between the distal side of the fin clamp and the proximal end of the humerus, whereby the collar of the humeral stem provisional is seated at a certain predetermined distance from the proximal end of the humerus;
attaching a ruler to the fin clamp, while the fin clamp is attached to the humeral stem provisional, for determining the position of the humeral stem provisional;
inserting at least one fixation pin into the humerus at a point near the ruler, in order to facilitate proper positioning of the stemmed humeral component into the same location as the humeral stem provisional; and removing the humeral stem provisional, with the ruler attached thereto, while maintaining the at least one fixation pin inserted into the humerus.

24. A method for temporarily securing a humeral stem provisional within a humerus during shoulder arthroplasty, said method comprising the steps of:
attaching a sleeve to a stem of the humeral stem provisional;
inserting the humeral stem provisional, with the sleeve attached thereto, into a canal located within a proximal portion of the humerus;
after determining that the humeral stem provisional is properly sized and positioned, removing the humeral stem provisional and the sleeve;
and implanting a permanent humeral component in the same location and orientation as the humeral stem provisional previously removed.

25. The method according to Claim 24, further comprising the step of selecting a sleeve of an appropriate size to correspond to the size of the humeral stem provisional being used.

26. The method according to Claim 25 wherein a sleeve of a single size corresponds to a plurality of humeral stem provisionals of a plurality of different sizes.

27. A system of humeral stem provisionals used during shoulder arthroplasty, said system including:
a plurality of humeral stem provisionals each including a stem;
and at least one sleeve configured to fit upon the stem of each humeral stem provisional, wherein said sleeve aids in securely seating the associated humeral stem provisional within a canal located within a proximal portion of a humerus:

28. The system according to Claim 27, wherein said at least one sleeve includes a plurality of sleeves.

29. The system according to Claim 28, wherein said plurality of sleeves includes sleeves that correspond to a plurality of provisional components of different sizes, whereby the total number of different sized sleeves is less than the total number of different sized humeral stem provisionals.

30. The system according to Claim 27 wherein said at least one sleeve is made of foam.

31. The system according to Claim 27, wherein said at least one sleeve includes a tether attached thereto and extending from one end thereof for facilitating removal of said sleeve from the canal, if said sleeve and said humeral stem provisional become separated during removal of said humeral stem provisional from the canal.

32. The system according to Claim 27, wherein said at least one sleeve includes at least one axial slit on an inner periphery thereof.

33. A ruler for use in positioning a stemmed humeral component, or a humeral stem provisional, within a humerus during shoulder arthroplasty, the ruler comprising:
a scale with incremental marks indicting distance from a zero point; and a securing assembly for securing the ruler to another device used for positioning a stemmed humeral component, or a humeral stem provisional, within a humerus during shoulder arthroplasty.

34 34. The ruler according to Claim 33, further comprising an elongated hole with an open end at an end of the ruler opposite from an end including said securing assembly;

35. The ruler according to Claim 33, wherein said securing assembly includes a setscrew.

36. A system including a fixation pin and driver used for inserting the fixation pin into a bone for marking the orientation of a provisional prosthesis to duplicate proper orientation for the final prosthesis, the system comprising:
a fixation pin with a threaded portion near a first end and a portion of non-circular cross-section near a second end thereof; and a driver including a first end portion and a second end portion, where said first end portion includes an axially extending aperture with a portion thereof that is of a non-circular cross-section corresponding to the non-circular cross-section of said fixation pin.

37. The system according to Claim 36, wherein said non-circular cross-section portion of said aperture in said driver is separated from the first end of said driver by a circular cross-section portion of said aperture.

38. The system according to Claim 37, further comprising:
a channel formed within said circular cross-section portion of said aperture in said driver; and a c-ring seated within said channel.

39. The system according to Claim 36, wherein said second end portion of said driver is configured and arranged to be connected to a drill.

40. The system according to Claim 36, wherein said second end portion of said driver is configured and arranged to be connected to a T-handle to facilitate manual rotation.

41. The system according to Claim 36, wherein said second end portion of said driver is configured and arranged to be connected to a drill and said second end portion of said driver is also configured and arranged to be connected to a T-handle to facilitate manual rotation.