BONE FIXING DEVICE

Abstract: A bone fixing device includes at least one elongated link (12, 14), and a number of clamp units (38) movably mounted on one such elongated link (12, 14). Each elongated link (12, 14) is substantially round in end view, and each clamp unit (38) includes a clamp body (40) slidably and rotatably mounted on its link (12, 14). Clamp locking means (60, 54, 56) are provided for locking the clamp body (40) on the link (12, 14); and a bone pin carrier (42, 44) is rotatably mounted on the clamp body (40) and is adapted to receive at least one bone pin (94). Carrier locking means (96) is provided for locking the bone pin carrier (42, 44) relative to the clamp body (40).

Description: TITLE OF INVENTION Bone fixing device. FIELD OF INVENTION The present invention relates to a bone fixing devices. BACKGROUND TO INVENTION Bone fixing devices are used for various orthopaedic purposes, and many different types of such devices are known. The known devices generally are provided with various types of pin clamping devices. In most cases these are not adjustable in various directions, and such adjustability is desirous in many instances. It is an object of the invention to provide a bone fixing device having pin clamping units which are adjustable in various directions. SUMMARY OF INVENTION According to the invention, there is provided a bone fixing device, which includes at least one elongated link, and a number of clamp units movably mounted on one such elongated link, the device being characterized thereby that each elongated link is substantially round in end view, and that each clamp unit includes a clamp body slidably and rotatably mounted on its link; that clamp locking means are provided for locking the clamp body on the link; that a bone pin carrier is rotatably mounted on the clamp body and is adapted to receive at least one bone pin; and that carrier locking means is provided for locking the bone pin carrier relative to the clamp body. The elongated link may be an elongated cylindrical bar. A number of elongated links may be provided, the links being connected in series by link connecting means. The link connecting means may include a projection at an end of a link, and a locking surface provided on the projection adapted to be locked to a similar locking surface provided on a projection of another link. The locking surface may be a ratchet surface. The clamp body may include a hole for receiving its link and a split gap extending outwardly from the hole, and the clamp locking means being adapted to pull the body together at its split gap to clamp the body onto its link. The clamp locking means may include a hole in the clamp body extending transversely through the split gap, and a bolt adapted to be passed through the hole for pulling the body together. The bone pin carrier may include a base disc rotatably mounted on the clamp body, a top disc; the carrier locking means being adapted to pull the top disc and the base disc relatively together to clamp at least one bone pin between them. The top disc and the base disc may have cooperating locating grooves for receiving bone pins. The base disc may have a pin extending towards the top disc and the top disc may have a hole for receiving the pin so as to prevent relative rotation between the base disc and the top disc. The carrier locking means may include a threaded bolt adapted to pass through a hole in the top disc and a hole in the base disc to be threaded into a threaded hole in the clamp body. A connecting link with at least one groove may be provided, and link connectors for connecting the connecting link to two elongated links. At least one of the elongated links may include an outer sleeve and an inner rod extending out of the outer sleeve and being connected to another elongated link, and adjustment means for adjusting the inner rod relative to the outer sleeve. BRIEF DESCRIPTION OF DRAWINGS The invention will now be described by way of example with reference to the accompanying schematic drawings. In the drawings there is shown in: Figure 1 a side view of a first embodiment of a bone fixing device in accordance with the invention; Figure 2 on an enlarged scale, a side view of one link of the device illustrated in Figure 1 ; Figure 3 a view seen along arrow III in Figure 2; Figure 4 an end view seen along arrow IV in Figure 2; Figure 5 on an enlarged scale, a view of a second link of the device illustrated in Figure 1 ; Figure 6 an end view seen along arrow VI in Figure 5; Figure 7 a view seen along arrow VII in Figure 5; Figure 8 on an enlarged scale, an end view of the base part of a bone clamping unit seen along arrow VIII in Figure 1 ; Figure 9 a view seen along arrow IX in Figure 8; Figure 10a plan view seen along arrow X in Figure 8; Figure 11 a view of a first bolt for use in the unit illustrated in Figures 8 to 10; Figure 12 a view of a second bolt for use in the device illustrated in Figures 8 to 10; Figure 13 on an enlarged scale, a plan view of the base disc of the bone clamping unit illustrated in Figure 1 ; Figure 14 a side view seen along XIV in Figure 13; Figure 15 a plan view seen along arrow XV in Figure 13; Figure 16 on an enlarged scale, a plan view of the top disc of a bone clamping unit as illustrated in Figure 1 ; Figure 17a view seen along arrow XVII in Figure 16; Figure 18 a view seen along arrow XVIII in Figure 16; Figure 19 on an enlarged scale, a side view of another link for use in the device illustrated in Figure 1 ; Figure 20 an end view seen along arrow XX in Figure 19; Figure 21 an end view seen along arrow XXI in Figure 19; Figure 22 on an enlarged scale, a side view of a further type of link for use in the bone fixing device illustrated in Figure 1 ; Figure 23 an end view seen along arrow XXIII in Figure 22; Figure 24 a view seen along arrow XXIV in Figure 22; Figure 25 on a reduced scale, a plan view of a pelvic bone fixing device including various components as illustrated in the preceding drawings; Figure 26 a view seen along arrow XXVI in Figure 25; Figure 27 on an enlarged scale, a view of the connecting link in the pelvic bone fixing device illustrated in Figure 25; Figure 28 an end view seen along arrow XXVIII in Figure 27; Figure 29 on an enlarged scale, an exploded view of the link connector shown in Figures 25 and 26; Figure 30 on an enlarged scale, a view of the end pin holder illustrated in Figures 25 and 26; Figure 31 a view seen along arrow XXXI in Figure 30; Figure 32 a view seen along arrow XXXII in Figure 30; Figure 33 on an enlarged scale, a view of the base disc of the end pin holder illustrated in Figures 25 and 26; Figure 34 a view seen along arrow XXXIV in Figure 33; Figure 35 a view seen along arrow XXXV in Figure 33; Figure 36 on an enlarged scale, a view of the outer disc of the pin holder illustrated in Figures 25 and 26; Figure 37 a view seen along arrow XXXVII in Figure 36; Figure 38 a view seen along arrow XXXVIII in Figure 36; and Figure 39 an exploded view of an adjustable link for use with the bone fixing device illustrated in Figure 1. DETAILED DESCRIPTION OF DRAWINGS Referring to Figure 1 , an orthopaedic or bone fixing device in accordance with the invention, generally indicated by reference numeral 10, includes a first link 12 and a second link 14. The links 12, 14 are made of round solid metal bars but also can be made of hollow cylindrical material if required. The first link 12 (also illustrated in Figures 5 to 7) has a rounded end 16 and, opposite thereto, a projecting connector part 18 having an internally threaded hole 20 and a circular ratchet surface 22. The second link 14 has a rounded end 24 and, opposite thereto, a converting part 26 having a hole 28 and a circular ratchet surface 30. The hole 28 is recessed at 32 as shown. The second link 14 is also illustrated in Figures 2 to 4. In use the links 12, 14 are placed together so that their ratchet surfaces 22, 30 are in engagement. The links 12, 14 are rotated to be in a required position, either being in alignment or defining any angle as desired between them. Then the threaded bolt 34 is screwed into the threaded hole 20 until its head 36 is received in the recess 32. The head 36 is a so-called Allan-screw. The links 12, 14 carry bone pin holders 38. The pin holders 38 include a link connector body 40, a rotatable base disc 42 and an upper disc 44. Details of the base part are illustrated in Figures 8 to 10. The body 40 includes a cylindrical body which is split into two body parts 46, 48 defining a circular hole 50 therein by way of a gap or passage 52 extending to the outside. An internally threaded hole 54 is provided in the part 46 and a hole 56 with a recess 58 in the part 48. The screw threaded bolt 60 shown in Figure 11 having a threaded shank 62 and a head 64 is passed through the passage 56 and screwed into the threaded hole 54 for clamping the parts 46, 48 onto a link 12, 14 received in the hole 50. The body 40 has a disc shaped head 66 of which the upper face 68 has a circular ratchet shape. A pillar or boss 70 extends outwardly from the head 66 and a threaded passage 72 is provided in the boss 70. The base disc 42, which is also illustrated in Figures 13 to 15, includes a bottom ratchet shaped surface 74 and opposite thereto an engagement surface 76 in which two parallel grooves 78, 80 which are truncated shaped in end view, are provided. A pin 82 extends from the surface 78. The disc 42 has a central hole 84 for receiving the boss 70. (If required the faces 68, 74 need not be ratchet shaped but only be in frictional contact for locking together). The upper disc 44, also illustrated in Figures 16 to 18, includes a bottom surface 86 in which two recesses 88, 90 which are of truncated shape in end view, are provided. The disc 44 has a hole 92 for receiving the pin 82 of the disc 42 so as to align the recesses 78, 80 and 88, 90 for receiving bone 94 as shown in Figure 1. A screw or bolt 96, illustrated in Figure 12, has a threaded shank 98 and a head 99. It is passed through the hole 100 in the disc 44 and is screwed into the threaded hole 72 in the boss 70 of the body 40. The disc 42 and 44 can be rotated as required into any angular position and then are fixed in this position by way of the bolt 96. As is shown in Figure 1 the bone pin holder 38 can be moved longitudinally on its link 12 or 14 as indicated by arrow A, or be rotated on its link 12 or 14 as indicated by arrow B, and the base disc 42 and top disc 44 can be rotated as indicated by arrow C. The bone pins 44 therefore can be moved in three directions making numerous angles and positions possible. The links 12, 14 can be pivotted relative to each other as indicated by arrow D in Figure 3. This applies to all other ratchet contact surfaces of components shown in the drawings. In Figures 19 to 21 a further embodiment of a link is shown. This link, generally indicated by reference numeral 102, has two opposite connector parts 104, 106 which are on opposite sides of the longitudinal central axis of the cylindrical body 108. They have circular ratchet surfaces 110 and 112 respectively and a hole 114 and an internally threaded hole 116 respectively. These ratchet surfaces 110 and 112 are fitted to complementary ratchet surfaces of further links as required. In Figures 22 to 24 a further embodiment of a link is shown. This link, generally indicated by reference numeral 118, includes a cylindrical body 120 and connector parts 122 and 124 at opposite ends. The connector parts have circular ratchet surfaces 126, 128 as shown with a hole 130 and an internally threaded hole 132. As will be seen, the ratchet surfaces 126, 128 are displaced at 90° relative to each other. Referring to Figures 25 and 26, the bone fixing device adapted for use regarding pelvic bones of a patient, generally indicated by reference numeral 134, includes a central bar or link 136, two side links 138, 140 and two bone pin end carrying bars 142, 144 provided at the ends of the links 138, 140 respectively. The links 138 and 140 are identical and the pin carrying bars 142 and 144 are identical. The links 138, 140 are attachably connected to the central bar 136 by way of first connectors 146, which are identical, and the pin carrying bars 142, 144 carry bone pin holders 148, which are identical. The identical components will only be described with reference to the components associated with the link 138 but the same description applies to the components associated with the link 140. Referring to Figure 27, the central bar 136 is of elongated round shape and has two elongated slots 150, 152. Referring to Figure 29, the connector 146 includes a base clamp 154 which has a body 156 which is split with a hole 158 and a gap 160 extending therefrom so as to define two body parts 162 and 164. The parts 162, 164 respectively have an internally threaded hole 166 and a hole 168 with a recess 170. On top of the parts 162, 164 a disc shaped head 172 with a ratchet surface 174 and a boss 176 are located. The boss 176 has an internally threaded hole 178. The connector 146 further has a central disc 180 having a bottom ratchet surface 182 and a semi-circular recess 184 opposite thereto. A hole 186 is provided in it extending from the recess 184 to the ratchet surface 176 and being open at 188 to receive the boss 176. The connector 146 further has a top disc 190 having a semi-circular recess 192 and a boss 194 at its upper end in which a hole 196 passes down into the recess 192. When pressed together the link 138 (or 140) is inserted through the hole 158 and is clamped thereto in any desired angular position by way of a threaded bolt (not shown) inserted into the hole 168 and screwed into the threaded hole 166. The central part 180 is placed onto the part 156 in any desired position in that the boss 176 is placed into the hole 186. Thereafter the top disc 190 is placed onto the central disc 180 with the bar 136 fitting into the circular hole defined by the recesses 184 and 192. A pin (not shown) is passed through the hole 196 and through the slot 150 or 152 to be threaded into the threaded hole 178 for clamping the bar 136 tightly into position. Thus by suitable adjustment of the connector 146 any desired angular position can be obtained between the bar 136 and the link 138 or link 140. Referring now to Figures 30 to 38, the pin carrier bar 144 and its components are illustrated. The bar 144 has a round part 198 at its end 200 and a flat part 202 at its end 204. On the part 202 a round ratchet surface 206 is provided. Centrally an internally threaded hole 208 is provided. Although not shown, the link 138 at its end has a similar part with a round serrated formation. The ratchet surface 206 is placed into contact with this ratchet surface of the link 138 and is held in any desired angular position by way of a pin passing through the link 138 and being screwed into the threaded hole 208. The part 198 has a stub 210 in which an internally threaded hole 212 is provided. A pin carrier 148, illustrated in Figures 33 to 38 has a disc 214 with a central hole 215 for receiving the stub 210. It further has two grooves 216, 218 and a pin 220. These cooperate with a cap 222 illustrated in Figures 36 to 38. The cap 222 has a central hole 224 and a pin hole 226 to receive the pin 220. The cap 222 further has two grooves 228, 230 which, together with the grooves 216 and 218 define clamping passages for the bone pins 232 shown in Figure 25. A threaded screw (not shown) is passed through the hole 224 and is screwed into the threaded hole 212 for clamping the bone pins 232 in any desired position. By means of the device 134 and its components as illustrated in Figures 25 to 38 it therefore is possible to adjust the various components in numerous directions and to provide a multitude of variations depending on the pelvic size of a patient and the particular position where the required bone pins are to be located. Once in position the bone pins are fixed exactly and are held securely in this position. Figure 39 shows an exploded view of a further component to be used in conjunction with the bone fixing device as illustrated in the preceding drawings. The device, generally indicated by reference numeral 234 is a compression release adjustment device. It includes a tubular body 236 into which a link 238 is insertable from one end. The link 238 has a head 240 with a serrated connector as explained above for connection to a complementary link. The link 238 further has an internally threaded hole 242. A bar 244 having a threaded end 246 and a collar 248 and square shaped head 250 at the opposite end is inserted into the tubular body 236 until the collar 248 abuts against its externally threaded end 252. The head 250 is turned so that the screw thread end 246 turns into the threaded link 238. A pin 254 having a threaded shank is received in a threaded hole 256 of a saddle 258 provided on the body 236 and the pin 254 slides in a slot 260 provided externally in the link 238 to prevent rotation thereof. By suitable rotation of the head 250 the length of the device 234 can be varied, and thereby the distance between any pin holders 148 fitted thereon. An end cap 262 is screwed onto the threaded end 252 to keep the bar 244 in position. List of references 10 bone fixing device 12 first link 14 second link 16 rounded end 18 connector part 20 internally threaded hole 22 ratchet surface 24 rounded end 26 connecting part 28 hole 30 ratchet surface 32 recess 34 bolt 36 head 38 bone pin holder 40 body 42 base disc 44 upper disc 46 body part 48 body part 50 hole 52 passage 54 threaded hole 56 hole 58 recess 60 bolt 62 shank 64 head 66 disc shaped head 68 upper face 70 pillar or boss 72 threaded passage 74 ratchet surface 76 engagement surface 78 groove 80 groove 82 pin 84 hole 86 bottom surface 88 recess 90 recess 92 hole 94 bone pin 96 bolt 98 shank 99 head 100 hole 102 link 104 connector part 106 connector part 108 cylindrical body 110 ratchet surface 112 ratchet surface 114 hole 116 hole 118 link 120 body 122 connector part 124 connector part 126 ratchet surface 128 ratchet surface 130 hole 132 hole 134 bone fixing device 136 link 138 link 140 link 142 bar 144 bar 146 connector 148 pin holder 150 slot 152 slot 154 base clamp 156 body 158 hole 160 gap 162 body part 164 body part 166 hole 168 hole 170 recess 172 head 174 ratchet surface 176 boss 178 threaded hole 180 central disc 182 ratchet surface 184 semi-circular recess 186 hole 188 opening 190 disc 192 recess 194 boss 196 hole 198 round part 00 end of bar 202 flat part 204 end of bar 206 ratchet surface 208 threaded hole 210 stub 212 threaded hole 214 disc 215 central hole 216 groove 218 groove 220 pin 222 cap 224 hole 226 pin hole 228 groove 230 groove 232 bone pin 234 bone fixing device 236 tubular body 238 link 240 head 242 hole 244 bar 246 threaded end 248 collar 250 head 252 threaded end 254 pin 256 threaded hole 258 saddle 260 slot 262 end cap

Claims: PATENT CLAIMS 1. A bone fixing device, which includes at least one elongated link (12, 14), and a number of clamp units (38) movably mounted on one such elongated link (12, 14), characterized thereby that each elongated link (12, 14) is substantially round in end view, and that each clamp unit (38) includes a clamp body (40) slidably and rotatably mounted on its link (12, 14); that clamp locking means (60, 54, 56) are provided for locking the clamp body (40) on the link (12, 14); that a bone pin carrier (42, 44) is rotatably mounted on the clamp body (40) and is adapted to receive at least one bone pin (94); and that carrier locking means (96) is provided for locking the bone pin carrier (42, 44) relative to the clamp body (40). 2. A device as claimed in claim 1 , characterized thereby that the elongated link (12, 14) is an elongated cylindrical bar. 3. A device as claimed in claim 1 or claim 2, characterized thereby that a number of elongated links (12, 14, 13, 138, 140, 234, 236) are provided, the links being connected in series by link connecting means (18). 4. A device as claimed in claim 3, characterized thereby that the link connecting means (18) include a projection (26) at an end of a link (14), and a locking surface (30) provided on the projection (26) adapted to be locked to a similar locking surface (22) provided on a projection (18) of another link (12). 5. A device as claimed in claim 4, characterized thereby that the locking surface is a ratchet surface (22, 30). 6. A device as claimed in any one of the preceding claims, characterized thereby that the clamp body (40) includes a hole (50) for receiving its link (12, 14) and a split gap (52) extending outwardly from the hole (50), and the clamp locking means (60, 54, 56) being adapted to pull the body (40) together at its split gap (52) to clamp the body (40) onto its link (12, 14). 7. A device as claimed in claim 6, characterized thereby that the clamp locking means (60, 54, 56) include a hole (54, 56) in the clamp body (40) extending transversely through the split gap (52), and a bolt (60) adapted to be passed through the hole (54, 56) for pulling the body (40) together. 8. A device as claimed in any one of the preceding claims, characterized thereby that the bone pin carrier (42, 44) includes a base disc (42) rotatably mounted on the clamp body (40), a top disc (44); the carrier locking means (96) being adapted to pull the top disc (44) and the base disc (42) relatively together to clamp at least one bone pin (94) between them. 9. A device as claimed in claim 8, characterized thereby that the top disc (44) and the base disc (42) have cooperating locating grooves (88, 90; 78, 80) for receiving bone pins (94). 10. A device as claimed in claim 8 or claim 9, characterized thereby that the base disc (42) has a pin (82) extending towards the top disc (44) and the top disc (44) has a hole (92) for receiving the pin (82) so as to prevent relative rotation between the base disc (42) and the top disc (44). 11. A device as claimed in any one of claims 8 to 10, characterized thereby that the carrier locking means (96) includes a threaded bolt (96) adapted to pass through a hole (100) in the top disc (44) and a hole (84) in the base disc (42) to be threaded into a threaded hole (72) in the clamp body (40). 12. A device as claimed in any one of the preceding claims, characterized thereby that a connecting link (136) with at least one groove (150, 152) is provided, and link connectors (146) for connecting the connecting link (136) to two elongated links (138, 140). 13. A device as claimed in any one of the preceding claims, characterized thereby that at least one of the elongated links (234) includes an outer sleeve (236) and an inner rod (238) extending out of the outer sleeve (236) and being connected to another elongated link (12, 14), and adjustment means (244, 262, 260) for adjusting the inner rod (238) relative to the outer sleeve (236). AMENDED CLAIMS [received by the International Bureau on 06 March 2000 (06.03.00); original claims 1-13 replaced by new claims 1-12 (3 pages)] 1. A bone fixing device, which includes at least one elongated link (12, 14), and a number of clamp units (38) movably mounted on one such elongated link (12, 14), characterized thereby that each elongated link (12, 14) is substantially round in end view, and that each clamp unit (38) includes a clamp body (40) slidably and rotatably mounted on its link (12, 14); that clamp locking means (60, 54, 56) are provided for locking the clamp body (40) on the link (12, 14); that a bone pin carrier (42, 44) is rotatably mounted on the clamp body (40) and is adapted to receive at least one bone pin (94), the bone pin carrier (42, 44) including a base disc (42) rotatably mounted on the clamp body (40), and a top disc (44); and that carrier locking means (96) is provided for locking the bone pin carrier (42, 44) relative to the clamp body (40), the carrier locking means (96) being adapted to pull the top disc (44) and the base disc (42) relatively together to clamp at least one bone pin (94) between them. 2. A device as claimed in claim 1 , characterized thereby that the elongated link (12, 14) is an elongated cylindrical bar. 3. A device as claimed in claim 1 or claim 2, characterized thereby that a number of elongated links (12, 14, 13, 138, 140, 234, 236) are provided, the links being connected in series by link connecting means (18). 4. A device as claimed in claim 3, characterized thereby that the link connecting means (18) include a projection (26) at an end of a link (14), and a locking surface (30) provided on the projection (26) adapted to be locked to a similar locking surface (22) provided on a projection (18) of another link (12). 5. A device as claimed in claim 4, characterized thereby that the locking surface is a ratchet surface (22, 30). 6. A device as claimed in any one of the preceding claims, characterized thereby that the clamp body (40) includes a hole (50) for receiving its link (12, 14) and a split gap (52) extending outwardly from the hole (50), and the clamp locking means (60, 54, 56) being adapted to pull the body (40) together at its split gap (52) to clamp the body (40) onto its link (12, 14). 7. A device as claimed in claim 6, characterized thereby that the clamp locking means (60, 54, 56) include a hole (54, 56) in the clamp body (40) extending transversely through the split gap (52), and a bolt (60) adapted to be passed through the hole (54, 56) for pulling the body (40) together. 8. A device as claimed in any one of the preceding claims, characterized thereby that the top disc (44) and the base disc (42) have cooperating locating grooves (88, 90; 78, 80) for receiving bone pins (94). 9. A device as claimed in any one of the preceding claims, characterized thereby that the base disc (42) has a pin (82) extending towards the top disc (44) and the top disc (44) has a hole (92) for receiving the pin (82) so as to prevent relative rotation between the base disc (42) and the top disc (44). 10. A device as claimed in any one of the preceding claims, characterized thereby that the carrier locking means (96) includes a threaded bolt (96) adapted to pass through a hole (100) in the top disc (44) and a hole (84) in the base disc (42) to be threaded into a threaded hole (72) in the clamp body (40). 11. A device as claimed in any one of the preceding claims, characterized thereby that a connecting link (136) with at least one groove (150, 152) is provided, and link connectors (146) for connecting the connecting link (136) to two elongated links (138, 140). 12. A device as claimed in any one of the preceding claims, characterized thereby that at least one of the elongated links (234) includes an outer sleeve (236) and an inner rod (238) extending out of the outer sleeve (236) and being connected to another elongated link (12, 14), and adjustment means (244, 262, 260) for adjusting the inner rod (238) relative to the outer sleeve (236).

Inventors: ROETHIG HERMANN FLORIAN, ROETHIG, HERMANN, FLORIAN
Applicants: ROETHIG HERMANN FLORIAN, ROETHIG THOMAS MAX, ROETHIG, HERMANN, FLORIAN, ROETHIG, THOMAS, MAX
Application year: 1999
Main classification: A61B17
IPC codes: A61B17