Distraction clamp for treating injuries

A distraction clamp for treating a variety of injuries, comprising a rod clamp assembly having two clamps each configured to retain a rod, a pin clamp assembly comprising a bracket having a first mating surface, and two retainers each having a second mating surface. The bracket is structured to retain a plurality of pins. The first and second mating surfaces of the bracket and retainers respectively, are disposed in movable, retaining engagement with one another. The bracket is reciprocally movable along its length relative to the rod clamp assembly and to the clamp connector. The clamp connector serves to interconnect the rod clamp assembly to the pin clamp assembly. The clamp connector may include a biasing structure disposed and configured to movably bias the bracket in a spaced relation relative to the rod clamp assembly.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to an external fixation device in the form of a distraction clamp for use in treatment of a variety of injuries including, but not limited to, injuries to the lower leg, ankle, and arm. More specifically, the present invention relates to a distraction clamp that will be applied to an affected area after an injury to stretch out the ligaments and damaged bone structure. The distraction clamp of the present invention operates so that the damaged bone structure can assume a position that will allow the affected area to heal and reduce inflammation either permanently or temporarily prior to surgical treatment or other medical treatment.

Description of the Related Art

A very common injury is fracture of the lower leg ether in the tibia or the fibula. Other common injuries include fractures to other parts of the body such arm bones. One existing method for treating these types of injuries include stabilization of the affected area via a cast or other immobilization structures. This method though is not always as effective compared to other existing methods of treating these types of injuries. One method uses a distraction clamp or an external fixator that will restore the damaged bone structure back into its normal position. This method involves attaching pins to the bone structure within the affected area. Typically, the pins are attached during a surgical procedure, and are removed after healing of the area or after further surgical intervention. Attaching pins to the bone structure is done in order to prompt the desired alignment that will best achieve healing of the affected area. As such, external fixators and distraction clamps work by attaching a plurality of pins to different parts of the bone structure. The different pins are connected to the devices and the affected area is stretched and positioned to achieve the desired alignment of the bone. Additionally, this process stretches the surrounding ligaments and corresponding muscle tissue therefore promoting healing and stability of the affected area. Existing devices include adjustable external fixators. Some of the existing devices include openings which may hold pins in an array of different positions. Other fixation devices incorporate clamps and rods which are movable and adjustable.

It would be beneficial to provide a distraction clamp incorporating some of the features of existing fixator devices, but also incorporating a movable pin retaining structure. It would be helpful if this pin retaining structure were reciprocally movable along its length, and selectively retainable in a variety of different positions, to provide optimal alignment and stretching of the injured area. Therefore, a benefit may be realized by providing a distraction clamp having a bracket that can retain a plurality of pins, and also having a corresponding set of retaining structures. It would be advantageous to provide a bracket and corresponding retaining structures both having mating surfaces so as to form a mating engagement that could facilitate movement and selective retention of the bracket in a variety of different positions. Another advantage could also be provided if the position of the bracket could be adjusted using only one hand. A further benefit may also be realized by providing a distraction clamp with a biasing structure to facilitate movement of the bracket.

SUMMARY OF THE INVENTION

The present invention is directed to a distraction clamp which generally comprises a structure configured to retain a plurality of pins attached to a bone, a structure configured to retain a plurality of rods, and a connector. More specifically, the distraction clamp of the present invention comprises a rod clamp assembly, a pin clamp assembly, and a clamp connector that interconnects the rod clamp assembly to the pin clamp assembly.

The pin clamp assembly generally comprises a bracket and a plurality of retainers. Preferably the pin clamp assembly should comprise two retainers. The bracket may come in the form of a solid piece, or may be formed by a plurality of interconnected pin clamp segments. The bracket, and in some embodiments the pin clamp segments, may be adjustable to receive and retain a plurality of pins attached to a bone. The bracket and the retainers will both have corresponding first and second mating surfaces to create a mating engagement between the bracket and the retainers. Both mating surfaces may come in the form of a plurality of spaced apart ribs configured in an adjustable threaded engagement. The mating engagement between the bracket and the retainers should generate a frictional resistance that permits selective retention of the bracket. However, the frictional resistance should not prevent reciprocal movement of the bracket in relation to the retainers. As such, movement of the bracket according to the present invention occurs in a direction substantially transverse to the length of the clamp connector and substantially along the length of the bracket. As such, the mating engagement between the bracket and the retainers permits movement and selective retention of the bracket relative to the retainers in a plurality of different positions.

The rod clamp assembly comprises a plurality of clamps configured to retain a rod. In preferred embodiments of the present invention, the rod assembly comprises two clamps. The clamps may comprise a plurality of clamp segments. Generally, each clamp comprises two clamp segments each disposed in spaced relation to one another. This spaced relation between the clamp segments forms a socket that retains a rod. The size of the socket may be adjusted to retain rods of varying dimensions. Preferred embodiments of the present invention may include sockets configured to retain rods of cylindrical shapes. But, clamps may also be configured to retain rods of varying shapes, not just cylindrical.

The rod clamp assembly of the present invention comprises a plurality of connectors. Each connector corresponds to each clamp of the rod clamp assembly. Each connector interconnects its corresponding clamp to the clamp connector. The connectors may comprise a plurality of openings. At least one opening will be structured to retain its corresponding clamp. The opening that retains the clamp may be in the form of an adjustable sleeve. In some preferred embodiments the size of the sleeve will be cylindrical. The size of the sleeve should be sufficient to retain a clamp in movable relation with respect to the connector. Thus, the clamp remains movable, and in some embodiments rotational, relative to its corresponding connector. Movement restriction members may be disposed on the clamp or the sleeve to facilitate selective retention of the clamp in a variety of orientations within the sleeve. Movement restriction devices may also be disposed on the clamp connector to also facilitate selective retention of the rod clamp assembly with respect to the pin clamp assembly.

The connector of the rod clamp assembly generally comprises a different opening configured to receive the clamp connector thereby interconnecting the rod clamp assembly to the rest of the distraction clamp. This opening of the connector should be of sufficient diameter so that the clamp connector may pass therethorugh. This opening may come in the form of a cylindrical channel to permit rotation of a clamp connector having a cylindrical shape. The connector is disposed in a movable, and in some embodiments a rotational, relation with respect to the clamp connector and with respect to the pin clamp assembly.

As previously mentioned the clamp connector of the present invention interconnects the rod clamp assembly to the pin clamp assembly. Preferred embodiments of the present invention include a clamp connector having an elongated cylindrical shape. An elongated cylindrical shape of the clamp connector is not always required as the distraction clamp of the present invention may comprise a clamp connector having other shapes. As mentioned above, the clamp connector interconnects connectors of the rod clamp assembly to the pin clamp assembly.

In some embodiments of the present invention, the connectors of the rod clamp assembly may also be disposed in mating engagement with respect to pin clamp assembly. More specifically, the connectors and the retainers may have corresponding second and third mating surfaces. These mating surfaces create a mating engagement that permits movement and selective retention of the connectors, and consequently the rod clamp assembly, relative to the retainers, and relative to the pin clamp assembly. Furthermore, the connectors may be disposed in a rotational relation to the clamp connector, to the retainers, and to the rod clamp assembly. The third and fourth mating surfaces of the connectors and the retainers may also comprise pluralities of spaced apart ribs cooperatively disposed to form a threaded engagement. In some embodiments, the spaced apart ribs may be disposed on the retainers and on the connectors in a radial pattern thereby enabling rotation and selective retention of the connectors relative to the retainers.

The clamp connector of the present invention may also comprise a biasing structure disposed and configured to movably bias the bracket in a spaced relation to the rod clamp assembly. The biasing structure may comprise springs or other mechanical devices. The biasing structure is configured to create a spaced relation between bracket and the rod clamp assembly. More specifically, the biasing structure forces a separation of the connectors with respect to the retainers. As such, there is not mating engagement between the connectors and the retainers disposing the pin clamp assembly, and more specifically the bracket, in a spaced relation to the rod clamp assembly. Generally, the bracket should remain reciprocally movable with respect to the rod clamp assembly regardless if the clamp connector comprises a biasing structure. However, the biasing structure facilitates this reciprocal movement of the bracket.

Additional features of the distraction clamp of the present invention comprise locking features. The present invention may comprise a locking member which disposes the distraction clamp in an “operative orientation.” This “operative orientation” may be substantially defined as a movement restricting relation between the rod clamp assembly, the pin clamp assembly, and the clamp connector. In the “operative orientation”, only the clamps should remain movable, and in some embodiments rotational, with respect to the connectors. In this “operative orientation” there should be no movement of the bracket with respect to the rod clamp assembly.

The locking member of the clamp connector may be formed by a driven engagement between the clamp connector and a nut. The clamp connector of the present invention may comprise a clamp connector having a threaded section. Additionally, the nut may have an opening with an internally threaded surface. The threaded section of the clamp connector may be disposed in driven engagement with the internally threaded surface of the nut. As such, the nut may be disposed in movable and driven engagement with respect to the clamp connector. The user may adjust, and in some embodiments rotate, the nut relative to the clamp connector. Relative rotation of the nut to the clamp connector will result in movement of the nut along the length of the threaded portion of the clamp connector.

Before the user adjusts the nut, the rod clamp assembly may be initially disposed in a movable and spaced relation relative to the pin clamp assembly. At this stage, the user has the ability to adjust the distraction clamp. After the user has finished adjusting the distraction clamp, the user may proceed to adjust the nut in order to dispose the distraction clamp in the “operative orientation”. Adjustment of the nut will consequently force movement of the same along the length of the clamp connector. The nut will consequently induce at least one of the connectors to move along the length of the clamp connector. This relative movement of the connectors, and consequently the rod clamp assembly, will eliminate the spaced relation between the rod clamp assembly and the pin clamp assembly. Further adjustment of the nut will create a mating engagement between the retainers and the bracket, and between the connectors and the retainers. Even further adjustment of the nut will increase the frictional resistance between generated by this mating engagement thereby preventing any further movement of the bracket, retainers, and connectors.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

As represented in the accompanying figures, one preferred embodiment of the distraction clamp of the present invention is generally indicated as10throughout. With primary reference toFIG. 1, the distraction clamp10includes a rod clamp assembly20interconnected by a clamp connector40to a pin clamp assembly30. The rod clamp assembly20generally comprises two clamps generally indicated as21. Each of the two clamps21is connected to the clamp connector40, and each is dimensioned and configured to retain a rod. The clamps21may be made out of a plurality of clamp segments, and in at least one embodiment two clamp segments, generally indicated as22and24. As shown inFIGS. 1-3 and 9-10, the clamp segments22and24may be disposed in a spaced relation so as to form a socket25. By way of example only, the illustrative embodiments as shown inFIGS. 1-3 and 9-10show a socket25formed by the two clamp segments22and24disposed in a spaced relation. As should become apparent, the size of the socket25may be adjusted to accommodate a variety of rods of different sizes. In the illustrative embodiments as shown inFIGS. 1-4 and 9-10, the size of the socket25may be adjusted by a clamp segment connector23. The clamp segments22and24may comprise corresponding openings to receive the clamp segment connector23.

Furthermore, the clamp segment connector23may comprise a threaded portion23′. The threaded portion23′ may be cooperatively disposed in driven engagement with respect to a corresponding structure, such as an internally threaded surface29of a clamp segment22or24. This driven engagement serves to adjust the size of the socket25. In the illustrative embodiment as shown inFIGS. 4-5, the clamp segment22comprises an internally threaded surface29that corresponds to the threaded portion23′ of the clamp segment connector23. Accordingly, the threaded portion23′ of the clamp segment connector23may engage in driven relation with respect to the internally threaded surface29of the clamp segment22so that rotation of the clamp segment connector23in one direction will reduce the size of the socket25. Conversely, rotation of the clamp segment connector23in an opposite direction will increase the size of the socket25.

As represented inFIGS. 1-3 and 9-10, the rod clamp assembly20of the distraction clamp10of the present invention may also comprise a plurality of connectors, generally indicated as26. Each clamp21of the rod clamp assembly20should have one corresponding connector26. The connector26serves to interconnect each clamp21to the clamp connector40and to the pin clamp assembly30. The connector26may comprise a plurality of openings. In some embodiments the connector26may also comprise two openings. One opening interconnects the clamps21to the connector26, and the other opening may be configured so that the clamp connector40may interconnect the rod clamp assembly20to the pin clamp assembly30. The opening that interconnects the clamps21to the connector26may be in the form of a sleeve28or other retaining structure. The illustrative embodiment as shown inFIG. 3comprises two openings; one opening being configured to receive the clamp connector40, and the other being configured to receive and interconnect either of the clamps21to the connector26.

The opening of the connector26configured to receive the clamp connector40may be in the form of a channel26′ having a cylindrical shape. In the illustrative embodiment as shown inFIGS. 3 and 9, a connector26comprises an opening having a channel26′. Moreover, the clamp connector40may also have a cylindrical shape. As such, the clamp connector40may be configured to have a smaller diameter than the channel26′ of the connector26so that the clamp connector40may pass through the channel26′. In some embodiments according to the present invention the cylindrical shapes of the clamp connector40and the channel26′ of the connector26result in the connector26being connected to and disposed in movable relation with respect to the clamp connector40. In the illustrative embodiment as shown inFIG. 1, two different connectors26are interconnected to the clamp connector40and are cooperatively structured so that they can move, and in this illustrative embodiment rotate. In the illustrative embodiment as shown inFIG. 1, the two different connectors26may rotate, not only with respect to the clamp connector40, but also with respect to the pin clamp assembly30. It should be appreciated that the clamp connector40of the present invention may serve to movably interconnect, and in some embodiments rotationally interconnect, the rod clamp assembly20to the pin clamp assembly30.

The distraction clamp10of the present invention is capable to disposing the rods in a rotational relation with respect to the connectors26. Furthermore, the distraction clamp10of the present invention may also permit rotation of the connectors26, and therefore rotation of the clamps21and rods, with respect to the an axis defined by the length of the clamp connector40. This ultimately results in the rods being movable in several directions making the present invention advantageous in that the user will have great flexibility in adjusting the position of the rods.

The connector26according to the present invention may comprise a sleeve28. As shown in the illustrative embodiment as represented inFIG. 3, the opening of the connector26configured to receive one of the clamps21may be in the form of a sleeve28. Additionally, the sleeve28may be adjustable to accommodate the size of the clamp21. As should become apparent, each connector26interconnects its corresponding clamp21to the clamp connector40thereby interconnecting the rod clamp assembly20to the pin clamp assembly30. More specifically, and by way of example, the clamps21may be inserted inside the sleeve28of the connector26, and the size of the sleeve28may be adjusted accordingly to ensure that the clamp21is retained within the sleeve28. In some embodiments, the size of the sleeve28should be adjusted so that each clamp21is disposed in movable relation with respect its corresponding connector26. In at least one embodiment of the present invention, the clamps21are not only movable, but also rotational with respect to their corresponding connector26. Moreover, the clamps21may be rotational with respect to an axis defined by the length of the sleeve28.

Each clamp21may comprise a movement restriction member, generally indicated as46, which may be cooperatively disposed, dimensioned, and structured to facilitate selective rotation between each clamp21and its corresponding connector26. The movement restriction member46may be configured in a variety of shapes, including but not limited to circular. Additionally, the movement restriction members46may be made out of a material such as, but not limited to, silicone, rubber, or another flexible material. Further, the movement restriction member46may be cooperatively configured with the corresponding connector26, to result in a semi-restrictive rotation of the clamp21, relative to the frame connector26. As such, this semi-restrictive rotation may be defined by the movement of restriction member46, which frictionally engages the interior of a corresponding surface. As an example, this interior of a corresponding surface may be the interior surface of the sleeve28. As a result of this frictional engagement, the clamps21are maintained in place and cannot freely rotate unless the user supplies enough rotational force to overcome the frictional resistance between the movement restriction member46and corresponding surface. As will be explained in further detail later, additional movement restriction members46may also be used to achieve and maintain a selective retention of other components.

As will be explained in greater detail hereinafter, pin clamp assembly30of the distraction clamp10of the present invention includes a bracket38structured to retain a plurality of pins that will be attached to a bone. The bracket38may be a solid piece or may be formed by a plurality of interconnected pin clamp segments32. In some embodiments, the bracket38is formed by interconnecting two pin clamp segments32. The illustrative embodiment as shown inFIGS. 1-2 and 10shows two pin clamp segments32interconnected to one another and thus forming a bracket38. Generally, the bracket38comprises a plurality of pin openings35which may configured to retain corresponding pins. The size of the openings35may be adjusted to match size of the corresponding pin. With reference to the illustrative embodiment as shown inFIG. 1, a bracket38is formed by two pin clamp segments32being interconnected by two different bracket connectors31. If needed, more than two bracket connectors31may be used.

As with the clamp segment connector23, the bracket connector31may also have a threaded surface. Furthermore a washer, generally indicated as33, may be used to better adjust and secure bracket connector31to the pin clamp segments. Other washers33may also be used accordingly to facilitate connections between different parts of the distraction clamp10. Additionally, and similar to the internally threaded surface29of the clamp segment22, either of the two pin clamp segments32may also comprise openings with internally threaded surfaces. As such the bracket connectors31may be similarly disposed in driven engagement with the interior threaded surface of the pin clamp segments32. Thus, the bracket connector31not only serves to interconnect the pin clamp segments32, but also serves to adjust the size of the pin openings35. As should become apparent, rotation in one direction of the bracket connector31will increase the size of the pin openings35while rotation in the opposite direction will decrease the size of the pin openings35.

Preferred embodiments of the pin clamp assembly30of the distraction clamp10according to the present invention generally comprise a plurality of retainers, generally indicated as36. In at least one embodiment, the rod clamp assembly20should have two retainers36. Moreover, the bracket38generally comprises a first mating surface, indicated as34. Likewise, each of the retainers36comprise a corresponding second mating surface, indicated as37. The first mating surface34of the bracket38may be formed on each of the individual pin clamp segments32. By way of example, the illustrative embodiment as shown inFIG. 7shows a first mating surface34formed on one side of a pin clamp segment32. As such, each of the two pin clamp segments32may have a first mating surface34. This results in the bracket38having a first mating surface34on either side. Alternatively, if the bracket38is made of a solid piece, a first mating surface34may be formed on one or more sides of the bracket38. The illustrative embodiment as shown inFIG. 1shows a bracket38having a first mating surface34formed on either side.

Generally, the first mating surface34of the bracket38and the corresponding second mating surface37of the retainers36will be disposed in movable and retaining engagement with one another. In order to achieve this movable and retaining engagement, either or both of the first mating surface34and second mating surface37may comprise a plurality of spaced apart ribs cooperatively structured to define a threaded engagement. The illustrative embodiment as shown inFIG. 6shows a retainer36having a second mating surface37that has a plurality of spaced apart ribs. Similarly, the illustrative embodiment as shown inFIG. 7shows a pin clamp segment32having a first mating surface34also having a plurality of spaced apart ribs. Generally, a retaining engagement, may be achieved when both the first and second mating surfaces34and37of bracket38and retainer36are disposed in mating engagement with one another. Moreover, an adjustably threaded engagement may be achieved when both sets of spaced apart ribs of the first and second mating surfaces34and37are disposed in a cooperative mating engagement that permits selective movement of the bracket38with respect to the retainers36. By way of example only, a retaining engagement of corresponding first and second mating surfaces34and37is shown in the embodiment as represented inFIG. 1. The cooperative engagement between the first and second mating surfaces34and37should provide enough frictional resistance so that the bracket38will be retained in place, unless the user supplies sufficient force to move the bracket38with respect to the clamp connector40and the rod clamp assembly20. Therefore, the frictional resistance and/or “threaded engagement” created by the engagement between the first and second mating surfaces34and37should not prevent movement of the bracket38with respect to the retainers36, the clamp connector40and the rod clamp assembly20. As will be explained in further detail—hereinafter, the clamp connector40may comprise a locking structure44which may be used to control the frictional resistance of the mating engagement between the first and second mating surfaces34and37.

The locking structure44may comprise a threaded section44′ disposed on one end of the clamp connector40. In at least one embodiment according to the present invention, the locking structure44may have a nut41. The nut41may have a cylindrical opening with an internally threaded surface41′. The threaded section44′ of the locking structure44may be configured to achieve a mating and driven engagement with the internally threaded surface41′ of the nut41. After such a mating and driven engagement is achieved between the threaded section44′ of the locking structure44and the internally threaded surface41′ of the nut41, the clamp connector40should remain movable, and more specifically rotational, with respect to the nut41.

The locking structure44of the clamp connector40may be configured to dispose both the rod clamp assembly20and the pin clamp assembly30in a movement restricting relation. This movement restricting relation therefore disposes the distraction clamp10in an “operative orientation”. This “operative orientation” may be defined as a cooperative mating engagement between the rod clamp assembly20, the pin clamp assembly30, and the clamp connector40. This cooperative mating engagement prevents movement, and more specifically, rotation of the connectors26of the rod clamp assembly20relative to the pin clamp assembly30. Furthermore, this cooperative mating engagement also prevents movement of the bracket38with respect to the retainers36, and also prevents movement of the bracket38with respect to the rod clamp assembly20. Thus, in the “operative orientation” of the distraction clamp10, only the clamps21may remain movable, and in some embodiments rotational, with respect to their corresponding connectors36and with respect to the pin clamp assembly30.

As stated previously, the clamp connector40may be configured in a cylindrical shape, and may also be configured in different sizes. With reference to the illustrative embodiment as represented inFIG. 9, the connector26of the present invention may also comprise an opening in the form of a channel26′ having a cylindrical shape. The channel26′ may have a sufficiently larger size than that of the clamp connector40. In some embodiments according to the present invention, both the channel26′ and the clamp connector40have cylindrical shapes wherein the diameter of the channel26′ is greater than the diameter of the clamp connector40. As such, the clamp connector40may pass through the channel26′ therefore permitting relative rotation of the rod clamp assembly20relative to the clamp connector40and the pin clamp assembly30.

Additional features of the clamp connector40are represented inFIGS. 2 and 10. As previously mentioned, other parts of the distraction clamp10according to the present invention may comprise additional movement restriction members46. For example, the clamp connector40may comprise a plurality of movement restriction members46that help to dispose and retain the rod clamp assembly20in a plurality of different positions or orientations relative to the pin clamp assembly30. As previously mentioned, the movement restriction members46may have a circular shape, and may be made out of a variety of materials that create a semi-restrictive rotation. The frictional resistance of the movement restriction members46should be sufficient to maintain a desired position or orientation of the rod clamp assembly20. But, at the same time, the frictional resistance should allow the user to supply enough rotational force to adjust the position of the rod clamp assembly20. As previously described in greater detail, the movement restriction members create a frictional resistance when disposed against a corresponding surface. In this case, corresponding surfaces may include the interior surfaces of either opening of the connectors26. The illustrative embodiment as shown inFIG. 8shows a movement restriction member46disposed on an opening of the connector26. Other corresponding surfaces may include surfaces within an inside of the bracket38, or in at least one embodiment, surfaces inside either or both of the pin clamp segments32which form the bracket38. As can be appreciated, once the movement restriction members46are disposed within the clamp connector40, and rod clamp assembly20and the pin clamp assembly30are interconnected by the clamp connector40, the movement restriction members46within the clamp connector40will provide sufficient frictional resistance to retain the rod clamp assembly20after the user adjusts its position. The movement restriction members46therefore can prevent free movement and rotation of the rod clamp assembly20with respect to the pin clamp assembly30. The rod clamp assembly20has two clamps21each being independently movable, and more specifically independently rotational, relative to the clamp connector40, and relative to the pin clamp assembly30. For example, one of the two clamps21may be moved and rotated while the other clamp21may remain stationary. As such, one clamp21may move or rotate without the other clamp21having a corresponding movement or rotation.

The clamp connector40of the distraction clamp10of the present invention may also comprise a biasing structure42. This biasing structure may be disposed on the clamp connector40. Additionally, the clamp connector40may be manufactured with an internal biasing structure. In one embodiment according to the present invention, the biasing structure42may comprise a plurality of springs42′, and in some embodiments three springs42′, disposed on the clamp connector40. With reference to the illustrative embodiment as shown inFIG. 10, one spring42′ may be disposed between each connector26and each retainer36. Another spring42′ may be disposed inside of the bracket38. The biasing structure42, and more specifically the springs42′ may be made out of a variety of materials including, but not limited to steel, stainless steel, or different metal alloys. Several other combinations between the location and number of movement restriction members may also exist according to the preference of the user.

The biasing structure42forces a separation between the rod clamp assembly20and the pin clamp assembly30. For example, the biasing structure42should be elastic enough to permit a retaining engagement between the rod clamp assembly20and the pin clamp assembly30. The biasing structure should also permit movement of the rod clamp assembly20with respect to the pin clamp assembly30. Additionally, the biasing structure42should also permit a spaced relation of the bracket38relative to the retainers36. This spaced relation between the bracket38and the retainers36consequently permits linear and reciprocal movement of the bracket38relative to the pin clamp assembly30and to the rod clamp assembly20. In a preferred embodiment according to the present invention, this linear and reciprocal movement is substantially parallel to an axis defined by the length of the bracket38, and substantially transverse relative to the rod clamp assembly20. Once the pins are retained within the bracket38and attached to the bone, the ability of the bracket to reciprocally move will allow the user to adjust the position of the distraction clamp10relative to the bone. The biasing structure42is a feature that facilitates reciprocal movement of the bracket38relative to the rod clamp assembly20. But, a biasing structure42is not always required in order to enable reciprocal movement of the bracket38with respect to the rod clamp assembly20. Some embodiments of the present invention are operational without the use of a biasing structure42. A retaining engagement according to the present invention, between the first and second mating surfaces34and37of the bracket38and retainer36respectively, is what permits reciprocal movement of the bracket38with respect to the rod clamp assembly20.

Another feature of the distraction clamp10of the present invention is that the user may adjust the locking structure44of the clamp connector40to dispose the rod clamp assembly20and the pin clamp assembly30, in either a mating engagement or in a spaced relation. The illustrative embodiments as showing inFIGS. 1 and 10show a clamp connector40having a locking structure44. The locking structure44, as shown in the illustrative embodiments ofFIGS. 1 and 10, comprise a locking structure44with a threaded section44′ cooperatively be configured to achieve a mating and driven engagement with an internally threaded surface41′ of a nut41. Due to the driven engagement between the nut41and the threaded section44′, rotation in one direction of the nut41will result in a substantially parallel movement of the nut41with respect to the clamp connector40. This movement of the nut41will further induce movement of the rod clamp assembly20in a way that eliminates any spaced relation between the rod clamp assembly20and the pin clamp assembly30. As such, the induced movement of the rod clamp assembly20will occur in a direction substantially parallel to the length of the clamp connector40. More specifically, each connector26will move along an axis defined by the length of the clamp connector40, and towards its corresponding retainer36so that a spaced relation no longer exists between the connector26and its corresponding retainer36. In at least one embodiment according to the present invention, further rotation of the nut41in the same direction will create a retaining engagement between first and second mating surfaces34and37of the bracket38and the retainer36respectively.

Conversely, rotation of the nut41in an opposite direction will result in a spaced relation between the rod clamp assembly20and the pin clamp assembly30. More specifically, rotation of the nut41will result in a spaced apart relation between the connector26and its corresponding retainer36, and between the retainer36and the bracket38. This spaced apart relation releases the retaining engagement achieved by the first and second mating surfaces34and37of the bracket38and the retainer36respectively, thereby disposing the bracket38in a movable relation with respect to the retainers36and the rod clamp assembly20. The user may rotate the nut41accordingly to achieve a retaining engagement that will selectively maintain the bracket38in place, but at the same time will permit movement of the bracket38when the user supplies enough force.

The bracket38, and in some embodiments the pin clamp segments32that form the bracket38, may have an opening of sufficient size so that the clamp connector40can pass therethorugh. Additionally, the retainers36may also comprise openings of sufficient size so that the clamp connector40can also pass through the retainers36. The retainers36as represented inFIGS. 6 and 8comprise openings of a size larger than the diameter of a clamp connector40, as shown for example inFIG. 10. With this configuration, the rod clamp assembly20may only rotate with respect to the length of the clamp connector40and with respect to the opening of the retainers36. Thus, the clamp connector40, the rod clamp assembly20, and the pin clamp assembly30remain stationary with respect to the length of the bracket38. At the user's option, the bracket38may be moved to dispose the distraction clamp10in a desired position relative to the bone. In at least one embodiment according to the present invention, a range of linear and reciprocal movement of the bracket38may be defined by the span of the opening of either the bracket38, or in other embodiments the span of the opening of the pin clamp segments32that form the bracket38. The illustrative embodiment as show inFIG. 7shows a pin clamp segment32with an opening configured to permit movement of the pin clamp segment32, and consequently the bracket38, according to the span of the opening.

Additional structural features of the distraction clamp10of the present invention include selective movement and retention of the rod clamp assembly20with respect to the pin clamp assembly30. In at least one embodiment according to the present invention, the connectors26may comprise a third mating surface, indicated as27. Likewise, the retainers36may comprise a corresponding fourth mating surface, indicated as39. Similar to the mating engagement between the first mating surface34of the bracket38and the second mating surface37of the retainer36, the third mating surface27of the connectors26and the fourth mating surface39of the retainers36are also disposed in adjustable retaining engagement with respect to one another defining a “variable orientation” of the rod clamp assembly20. Thus, relative rotation of the rod clamp assembly20may occur about an axis substantially defined by the length of the clamp connector40. As such, relative rotation may occur between the rod clamp assembly20between the pin clamp assembly30. Additionally, the retaining engagement between the third and fourth mating surfaces27and39will maintain the rod clamp assembly20in the desired orientation.

Subsequently, the user may further rotate the rod clamp assembly20in the same or a different direction and the retaining engagement of the third and fourth mating surfaces27and39will likewise maintain the desired orientation of the rod clamp assembly20. In at least one embodiment of the present invention, the third and fourth mating surfaces27and39may also comprise a plurality of spaced apart ribs cooperatively structured to collectively define an adjustable threaded engagement with one another. The spaced apart ribs of the third and fourth mating surfaces27and39may be configured in a radially threaded configuration. The illustrative embodiments as shown inFIG. 8shows a retainer36having a fourth mating surface39having spaced apart ribs disposed in a radial direction thus forming a different threaded configuration than previously explained.

Yet additional features of the distraction clamp10according to the present invention include stability of the bracket38to ensure substantially transverse movement of the same with respect to the rod clamp assembly20. In at least one embodiment according to the present invention, stability of the movement of the bracket38is achieved via a plurality of elongate grooves52formed on the bracket38, and via a plurality of pins54formed on the retainers36. Some embodiments according to the present invention may comprise a plurality of grooves52formed in either or both of the pin clamp segments32that form a bracket38. Reference may be had to the illustrative embodiment as shown inFIG. 7which shows a plurality of grooves52, and in this case two grooves52, formed on a pin clamp segment32. The illustrative embodiment as shown inFIG. 6shows a plurality of pins54, and specifically two pins54, formed on a retainer36. In at least one embodiment, the plurality of grooves52should be formed on the surface of the bracket38that will be disposed in retaining engagement with the retainer36, namely the first mating surface34. Similarly, the plurality of pins54should be formed on the surface of the retainer36which will be disposed in mating engagement with the bracket38, the second mating surface37. Each of said plurality of pins54corresponds to one of said plurality of grooves52, and both are cooperatively oriented and movably interconnected to one another. This cooperative orientation between the corresponding ones of said plurality of pins54and said plurality of grooves52will ensure that the bracket38can maintain a reciprocal, substantially transverse movement of the bracket38to the clamp connector40, the rod clamp assembly20and the retainers36. More specifically, the grooves52should be of sufficient size and span to receive their corresponding pins54, and to permit linear movement of the pins54along the length of the grooves52. In cooperation therewith, the clamp connector40passes through an elongated slot55formed in and extending along the length of each of the pin clamp segments32of the bracket38, thereby facilitating the aforementioned reciprocal movement of the bracket38, along its length, in a direction transverse to the clamp segment40. In preferred embodiments according to the present invention, there should be a minimum of two sets of corresponding grooves52and pins54formed on the bracket38and retainer36respectively. A minimum of two sets of grooves52and pins54will provide at least two different points of stability therefore preventing any pivotal movement or rotation of the retainers36with respect to the bracket38. As an illustration, the plurality of pins54as shown in the embodiment as shown inFIG. 6may be interconnected to the plurality of grooves52of the embodiment as shown inFIG. 7.

It should be noted that once the user has adjusted the distraction clamp10, the user can the dispose the same in the “operative orientation”. In at least one embodiment according to the present invention, two distraction clamps10each having two clamps21, should be used. Each rod should be attached on one end by a clamp21of a distraction clamp10, and on another end by a different clamp21of a different distraction clamp10. One advantage of the distraction clamp10, and more specifically the pin clamp assembly30of the present invention, is that the user does not need to use both hands, and can simply use one hand to adjust the position of the distraction clamp10relative to the bone. This is advantageous when the user may need to hold or operate other pieces equipment with the other hand. For example, the user may use one hand to adjust the position of the bracket38, and use another hand to operate the locking structure44.

Now that the invention has been described,