GB2031731A - Fracture reducing and joint immobilizing apparatus - Google Patents

Abstract

Upper and lower pin holder assemblies 1, 2 for fitting about a broken leg or arm, each support bone penetrating pins Figs. 9 to 12 (not shown) and are adjustably spaced by connector assemblies. Each connector assembly includes nut elements 54 which serve to move and lock an intermediate spherical component 50 along the connector shaft 47 and for locking the spherical component to the ring structure of a pin holder assembly. <IMAGE>

Description

SPECIFICATION Fracture reducing and joint immobilizing apparatus The present invention relates to orthopedic equipment and particularly to an apparatus for placement on a broken arm or leg to position and lock in place the fracture ends and immobilized to facilitate healing.

The practice of applying traction to a broken limb is well known as are the resulting inconveniences to the patient. More importantly, patients in traction for long periods develop other medical problems, Additionally, the several weeks in traction in a hospital is costly to the patient from an expense standpoint.

Numerous advantages reside in keeping a patient mobile and toward this end the general concept of providing mobile traction has been previously considered. To the extent such prior art devices are known, the same do not provide for a high degree of mobility in that they are bulky and complicated in nature.

Also the prior mobile traction devices do not provide a high degree of control to the surgeon and hence do not permit precise movement of the bone segments in all directions during reduction of the bone ends. Further, some of the prior devices do not allow for rotation of the fracture ends and require lengthy assembly procedures on the operating table.

The present invention is embodied in an apparatus for application to a bone fracture for the the positioning and immobilizing the fragment ends during healing while permitting the patient to be mobile.

The apparatus is embodied in upper and lower pin holder assemblies in spaced relationship on the injured limb. Each assembly serves to receive a bone penetrating pin or pins with the pin ends being lockable to their respective holder assembly.

Interconnecting the pin holder assemblies are elongate connector assemblies which adjustably couple the pin holder assemblies to one another to provide the surgeon a high degree of control over the bone ends during reduction. The connector assemblies include spherical components enabling universal movement of the pin holder assemblies.

Objectives of the orthopedic apparatus include: an apparatus for use by surgeons in the reduction of fractures which enables the wearer to remain mobile; an apparatus utilizing pin holder assemblies each of which receive one or more pins to secure the bone fragment in place; an orthopedic apparatus which provides adequate clearance from the patient's skin to enable normal ventilation and care of the limb; an orthopedic apparatus including spaced apart pin holder assemblies interconnected in a manner permitting a wide range of fracture movements; an orthopedic apparatus providing for the reception of a variable number of bone penetrating pins; an orthopedic device utilizing spherical coupling elements to interconnect two pin holder assemblies in a universally adjustable manner; an orthopedic apparatus enabling distraction, impaction, rotation, angulation and offset of the distal ends of the bone fragments.

In the drawings: Figure 1 is a front elevational view of the present apparatus on a human lower leg shown in phantom lines; Figure 2 is a side elevational view of Fig. 1; Figure 3 is a horizontal sectional view taken downwardly approximately along line 3-3 of Fig. 1; Figure 4 is a view similar to Fig. 3 but taken approximately along line 4-4 of Fig. 1; Figure 5 is a sectional, elevational view taken approximately along line 5-5 of Fig. 3 and showing details of an expansible coupling; Figure 6 is a view similar to Fig. 5 with the coupling component expanded into locked engagement with a ring component of the pin holder assembly; Figure 7 is a plan view of an expansible coupling component removed from associated structure; Figure 8 is a front elevational view of Fig.

7; Figure 9 is a side elevational view of a surgical pin used in securing a pin holder assembly to a fractured bone; Figure 10 is a side elevational view of the pin shown in Fig. 9 inserted within a bone with the pin ends adapted to receive threaded fasteners shown backed off from the pin ends and from supporting wall fragments; Figure 11 is a side elevational view of a pin end inserted in supported engagement with a wall fragment; Figure 12 is a side elevational view of a pin end and modified threaded fastener; Figure 13 is a side elevational view of an alignment bow for pin guidance; Figure 14 is a front elevational view of a modified expansible spherical coupling component removed from associated structure;; Figure 15 is a fragmentary elevational view of a solid wall structure with pin ends embedded therein; Figure 16 is an end elevational view of a fastener for surgical pin; Figure 1 7 is a side elevational view of a modified pin fastener arrangement; Figure 18 is a view similar to Fig. 1 but showing a modified form of the invention; Figures 19 and 20 are plan views taken along lines 19-19 and 20-20 of Fig. 18; Figure 21 is an enlarged detailed view of a modifield connector assembly taken along line 21-21 of Fig. 18; Figure 22 is a fitting for wall insertion which receives and locks the end of a surgical pin.

The reference numerals 1 and 2 indicate generally first and second pin holder assemblies referred to as upper and lower assemblies. While said pin holder assemblies are shown in Figs. 1 and 2 applied to the lower leg L of a patient, the present apparatus is suited with size changes to any limb of human or lower animal.

In Figs. 1, 2 and 3 wherein upper pin holder assembly 1 is disclosed, the reference numeral 3 indicates a closed ring structure comprising a front ring segment 4 and a rear ring segment 5. Ends at 4A and 5A of the ring segments each receive a fastener 6 extending therethrough and in threaded engagement with ends 4A. Countersunk fastener heads and oversize bores in reduced ends 5A permit a fastener 6 to serve as a pivot for the ring segments upon removal of the remaining fastener to permit opening and closing of the ring.

Front and rear ring segments 4 and 5 define curved openings 7, 8 and 9 formed about the segments center. Opening 7 is defined by concave wall surfaces 10 and 11 with surface 11 being on a curved plate 12 secured to front ring 4 by segment fasteners 13. Rear ring segment openings at 8 and 9 are longer and defined by concave opposed wall surfaces at 14 and 15 with surfaces 15 being on segmental clamping plates 16 secured by fasteners 17.

Pin supporting curved wall structures at 20 and 21. are each shouldered along a lower edge as at 20A-21A for rested engagement with front ring segment 4. Screws (not shown) secure the wall lower edges to front ring segment 4. The walls 20 and 21 are preferably of a synthetic resinous material for the reception of later described fasteners.

The upper edges of walls 20 and 21 are also shouldered at 208-218 for secured attachment to a bridge 23. Loads imparted to the walls are transmitted to front ring segment 4 without wall bending.

Walls 20 and 21 are provided with rows of axially spaced apart and aligned apertures at 24 and 25 to receive inserted surgical pin means. The apertures 24 and 25 may be of truncated conical shape tapering inwardly.

The openings 24-25 are in axial alignment with the axis intersecting the major axis of a broken bone B. A wide selection of pin locations are accordingly provided to accommodate various fractures. A modified wall structure is a solid wall for reception of an embedded pin end.

Lower pin holder assembly 2 is similar to the upper pin holder assembly but preferably is somewhat smaller and of a tapered nature for patient convenience. A closed circular ring structure 26 of the lower pin holder assembly includes a front ring segment 27 and rear ring segment 28. Segment ends are reduced at 27A and 28A to permit overlapping of same and the reception of fasteners 30 which terminate in threaded securement with reduced segments ends 27A. The segments ends 28A have somewhat oversize bores and are countersunk to receive the heads of fasteners 20.

A single fastener 30 serves as a pivot during opening and closing movement of ring struc-' ture 26 about a limb.

Front and rear ring segments at 27 and 28 each define curved concentric openings at 33, 34 and 35. The openings 33-35 are defined by concave wall surfaces as shown in Figs. 5 and 6. A curved plate 36 is secured to front ring segment 27 by fasteners 37. Rear ring segment 28 defines openings 34 and 35 in conjunction with curved plates 40 and 41 held in place by fasteners 42. The openings in ring structure 26 are defined by concave wall surfaces to receive spherical components of later described connector assemblies which join the upper and lower pin holder assemblies.

In place on lower circular ring structure 26 are walls 43 and 44 each shouldered along its upper edge as at 43A and 44A for seated engagement with ring structure 26 and specifically front ring segment 27 thereof. Said front ring is correspondingly adapted to assure retentive engagement of the wall with countersunk fasteners completing the securement.

The lower edges of walls 43 and 44 are also shouldered at 43B and 44B for securement to a bridge 49. Accordingly, walls 43, 44, front ring segment 27 and semicircular bridge 45 are joined in a rigid, permanent manner wherein loads imparted to the walls 43 and 44 by later described pins are bourne without wall deflection.

Walls 43, 44 are provided with rows of aligned apetures 45 and 46 for reception of surgical pin means. The wall openings are of truncated cone shape with the openings in one wall being in axial alignment with a corresponding opening in the other wall with a common aperture axis intersecting the axis of a bone fragment. One of said walls may be solid to receive the embedded end of a surgical pin.

Connector assemblies include shafts 47 each adjustably coupled to the upper and lower pin holder assemblies to permit a wide range of movement of one or both of said assemblies during fracture reduction. Spheri- t cal coupling components are indicated at 50 and are of ball shape and expansible by reason of being bifurcated. Retainers at 51 engage antirotation projections 52 on the coupling components with end segments engaging said appendages enabling outward displacement of the coupling halves as seen in Fig. 6. Expansion of the coupling is accomplished by conical bodies 53 formed on adjustable nut elements 54. The ends of said projections move within a recess defined by a spherical coupling component to spread the halves into biased engagement with the concave wall surfaces of their respective ring segments.In Fig. 14 a modified spherical coupling component 50' similar to the above described but having a circular retainer ring at 48 within semicircular grooves of each half. A bridge 50A prevents ring rotation while projections 52' prevent component rotation.

Shafts 47 are threaded to receive adjustable elements 54. Opposite rotation of the adjustable nut element associated with one spherical component of one coupling arrangement causes closing movement between two nut elements and hence expansion of the spherical component while the same direction of rotation of said elements of one coupling results in axial movement of the spherical component along shaft 47. Such axial movement imparts movement to the associated circular ring structure 3 or 26. For example, such advancement of all six nut elements associated with upper ring structure 3 will impart movement thereto repositioning same toward or away from the other ring structure.

Positioning of only a pair of nut elements 54 along a shaft 47 will tend to move a ring structure out of parallel relationship with the remaining ring structure which is important in alignment of the fracture ends.

Adjustment of nut elements 54 and coupling components 50 enables the surgeon to accomplish the necessary bone movements of distraction, impaction, rotation (manually), angulation and offset. The movement of the ring structures 3 and 26 are all made in incremental fashion and made with the aid of fluoroscopy. The coupling components, by reason of their universal movement capability, permit the upper and lower ring structures 3 and 26 to be shifted manually out of axial alignment and subsequently locked into an offset relationship thereby providing a capability for correcting offset problems of the fracture ends.

Surgical pin means are disclosed with a pin 56 having a cutting tip 57 with the pin partially threaded for bone penetration. Pin fasteners 58 are of the collelt type partially slotted lengthwise at 59. Pin 56 includes a flat sided end segment 56A for engagement with a power drill chuck at C. A groove 56B permits snapping off of end segment 56A after the pin is inserted into place and secured to a wall structure by means of fasteners 58.

Fasteners 58 are externally threaded and of an outer diameter at their smaller ends to facilitate starting and subsequent threaded en gagement with a wall opening 24-25, 45-46. Also fasteners 58 define internal bores at 58A for passage of the pin ends during seating of the fasteners. Flat areas at 60 on the fasteners receive a wrench tool to firmly seat the threaded fastener in a wall opening to lock the pin end in place. The leading end of each fastener is divided into quadrants each having a self tapping edge as at 61. Each fastener 58 is inwardly tapered so as to close about a pin as it is seated within a wall. In Fig. 15 a fragment 62 of a solid wall is shown which may be used in pin supporting cooperation with the apertured wall earlier described. A pin tip 57 seats within the wall material.

In Fig. 12, a modified fastener 63 has tool receiving flats at 64. External threads at 65 engage and seat within a wall opening. For retention of an offset pin tip 57, a body 66 of resinous material is mounted on the leading end of the fastener by a stud at 67. Advancement of fastener 63 urges resinous body 66 into tip securing engagement.

In Fig. 13, an alignment aid 69 is shown which is of U-shaped bow configuration having enlarged ends 70 each of which is of conical shape and slotted in a radial direction to permit central reception of a surgical pin 56 for subsequent guidance of same along the aligned axes of two aligned wall openings.

Upon passage of the pin tip 57 through the cone and into the proximity of the other wall aperture, the bow is removed to disengage the enlarged ends 70 from the aligned wall apertures whereupon the slots in said enlarged ends permit radial disengagement from the pin.

In use, the apparatus is designed to come preassembled and pre-adjusted by the nursing staff. By removing fasteners 6 and 30 the ring structures may be opened. Prior to placing the device upon the patient the length of the patient's leg is ascertained. By adjustment of nut elements 54 on shafts 47 the spacing of the ring structures 3 and 26 can be pre-set and locked into position.

With the device open, the leg is placed into position within the ring structures and held in its approximate reduced position. Pins 56 are then inserted through proper holes in the upright walls. The leg and the device are manipulated in order to provide clearance between the soft tissues of the leg and the apparatus. This step is also performed on the leg below the fracture site. Several pins 56 may be placed but usually two or three above and below the fracture are adequate. The apertures in the upstanding walls should be so selected to provide for aligned placement of the pin as is reasonably possible. Once the pins are placed and properly secured into the walls, a fastener 58 is torqued in place in the wall over each end.

After installation above and below the fracture site manipulation of the leg may now be done through loosening and adjusting of nut elements 54. Distraction of the fracture ends is accomplished by loosening the outer nut elements 54 on shafts 47 in all three locations on the lower or upper pin holder assem blies. The inner nut elements are then advanced.

Impaction of the fragment may be obtained by moving the inner nut elements 54 toward the center of shaft 47 and advancing the outer nut elements in the same direction. This operation is performed on only one ring at a time to maintain longitudinal alignment. If fracture angulation is required, such is accomplished by non-uniform extension or retraction of the nut elements 54 along shafts 47.

Angulation in any plane may be obtained by loosening all connector assemblies around the arcs of each ring structure and re-tightening same after fracture repositioning.

To offset the fracture ends, all nut elements 54 are loosened, the fracture aligned and then all nut elements tightened. To rotate a bone fragment around an axis relative to the remaining bone fragment, the nut elements 54 may be released on all three positions of one pin holder assembly and the ring rotated within the limits of the curved slots shown.

This device accordingly provides for angulation in any plane, offsetting in any plane, distraction, impaction and rotation of the fracture.

Additional connector assemblies may be added to the device for increased longitudinal strength.

If a limb has more than one fracture, the semicircular bridges at 23 and 49 may be removed and a ring structure similar to those at 3 and 26 applied to the distal edges of the upright walls. The added ring structures serve to receive the ends of additional connectors which in turn may secure in place still other pin holder assemblies of the type above described.

In Fig. 17 a modified pin fastener indicated generally at 72 provides for locking a surgical pin end to an apertured wall structure 20, 21, 43, 44 throughout a range of pin to wall relationships per the extreme broken line pin positions of Fig. 17. A wall engaging socket member at 73 is externally threaded at 73A for wall engagement. Said socket member has flat areas at 74 to receive a tool and is of open construction having internal threads 75 merging inwardly with a conical wall 76. The pin receiving end of socket 73 has an interior conical wall 77 which provides an enlarged opening to permit entry of a misaligned or inclined pin. Within socket member 73 is a movable collet 78 of spherical configuration and slotted at 78A to permit collet closure about surgical pin 56. A compression element 80 is threaded at 81 and has a conical compression wall at 82.Wall 82 and socket wall 76 cooperate upon advancement of compression element 80 to close collet 78 about pin 56. For purposes of accommodating a range of pin to fastener relationships, compression element 80 includes a conical wall surface 83 defining an enlarged end opening.

A tool applied to the flat areas 84 of compression element 80 enables locking of the pin to fastener 83 regardless of the pin and fastener being other than coaxial. Conical walls 77 and 83 define tapers of approximately thirty-seven degrees.

A modification disclosed in Figs. 18 through 22 includes first and second pin holder assemblies indicated generally at 91 and 92. Said assemblies may be of composite or cast construction with said first pin holder assembly having front and rear segments 93 and 94 joined by a pivot pin 95 and a lock 96 for opening of the assembly for placement about an injured limb. The second pin holder assembly is similar, with front and rear segments 97, 98 joined by a pivot pin 100 and a lock 101.

Wall structures at 102 are flanged at 102A for insertion into recesses at 97A in each pin holder assembly with set screws 104 securing the walls in place. Each of said wall structures is of a high density, synthetic material and devines threaded apertures 105 for the reception of pin securing means. Both full and half surgical pins may be supported by surgical pin fastener assemblies earlier described, or by a later described fitting. Additional pin holder assemblies may be attached to the wall structures shown to enable immobilizing the full or major portion of an injured limb.

In Figs. 18 through 21 modified connector assemblies each include a shaft 107 with upper and lower threaded segments on which are carried adjustable and locking nut elements 108 having conical ends for abutment with a sleeve of a ball and sleeve component at 110. A ball 11 or thereof is preferably of a durable synthetic material and in internal fixes engagement with the irregular, knurled surface of a sleeve 11 OB. A clamping member 111 is adjustably affixed to a pin holder assembly segment by cap screws 112 to permit frictional engagement of said member with ball component 11 or and subsequent locking of same in place after reduction of the fracture. Sleeve component 11 OB and hence adjustment of a pin holder assembly relative to a remaining like assembly is accomplished by the advancement of nut element 108 along shaft 107 and subsequent biasing of same against slidable sleeve 11 OB.

Pin means of the modified form may be as earlier described. A modified fitting for securement of a surgical pin end is shown in Fig.

22. The fitting 113 is of a tapered, threaded design for threaded insertion within a threaded aperture 105 in one of the wall structures 102. Tool receiving flat areas tho-re- on are at 113A on each fitting. The inner end of the fitting is conical at 1 14 to guide an advancing surgical pin end toward a central bore 115 in the fitting. A set screw 116 firmly seats and locks the inserted end of a surgical pin. Fasteners at 58 may also be used to attach the pin ends to the wall structures.

The present apparatus may be utilized in the treatment of burn victims as it permits a high degree of access to the limb exterior. The apparatus may also serve to immobilize an elbow or knee and to retain same against retraction during treatment of the arm or leg.

Claims (11)

1. An orthopedic apparatus for the reduction and immobilizing of the distal end segments of a fractured bone, said apparatus comprising, first and second pin holder assemblies each including pairs of pin receiving apertured wall structures, said assemblies adapted for disposition about a limb above and below the fracture site, pin means adapted for penetration of the bone segments and supported by at least one wall structure of said pair of wall structures of the first and second pin holder assemblies, and elongate conriector assemblies coupling said pin holder assemblies in adjustable spaced relationship, said connector assemblies each including a threaded shaft, pairs of axially adjustable elements thereon, ball and sleeve components disposed intermediate each of said pair of elements, clamping members carried by and spaced about on each of said pin holder assemblies for universal adjustable and clamping engagement with said ball and sleeve components, said axially adjustable elements operable upon axial repositioning to move a ball and sleeve component and thereby enable incremental varying of the spaced relationship between said pin holder assemblies, momentary release of said clamping members permitting alignment of the fracture ends by manual positioning of said pin holder assemblies, said axially adjustable elements thereafter adapted for advancement of a pin holder assembly and subsequent locked engagement with an intermediate ball and sleeve component for retention of the fracture ends in compression.

2. The orthopedic apparatus claimed in claim 1 wherein said pin holder assemblies each comprise a closed ring structure, said closed ring structures each defining a pair of recesses for the inserted installation of said wall structures.

3. The orthopedic apparatus claimed in claim 2 wherein said ring structures additionally define recesses on their upper and lower surfaces to permit the installation of said wall structures on both upper and lower sides of a ring structure.

4. The orthopedic apparatus claimed in claim 1 wherein said sleeve component has an irregular surface thereon to assure ball and sleeve integrity.

5. The orthopedic apparatus claimed in claim 1 wherein said pin means includes a surgical pin fastener assembly insertable within one of said wall apertures and securing the pin 6nd to the wall structure, said fastener assembly including a socket member, pin engaging collet means within said socket member, a compression member carried by said socket member and adapted for biasing engagement with said collet means to lockably engage the latter with said surgical pin.

6. The orthopedic apparatus claimed in claim 5 wherein said socket member and said compression member define openings of a size to admit entry of a surgical pin having an axis inclined to the major axis of said fastener assembly.

7. The orthopedic apparatus claimed in claim 6 wherein said collet means is of spherical configuration.

8. The orthopedic apparatus claimed in claim 1 wherein said pin means includes a surgical pin fastener assembly including a threaded fitting for installation within a wall aperture, said fitting defining a central bore and having an enlarged opening at its inwardly disposed end for the reception and guidance of a surgical pin end, said fitting additionally including a set screw for locking engagement with the surgical pin.

9. The orthopedic apparatus claimed in claim 1 wherein said pin means includes a surgical pin and externally threaded pin fastener defining an internal bore for reception of a pin end segment, said fastener having tool receiving surfaces thereon and slotted in a lengthwise direction and thereby adapted for gripping engagement with a pin end segment upon advancement of said fastener into an aperture in one of said wall structures.

10. The orthopedic apparatus claimed in claim 1 additionally including an alignment aid of U-shaped configuration having ends adapted for temporary engagement with aligned apertures in the wall structures of a pin holder assembly, said ends axially guiding a surgical pin being installed.

11. An orthopedic apparatus for the reduction and immobilizing of the distal end segments of a fractured bone constructed and arranged to operate substantially as herein described with reference to and as illustrated in the accompanying drawings.