Hand-held instruments that access interior body regions

A composite instrument is provided comprising a first functional instrument and a second functional instrument when the first functional instrument is coupled with the second functional instrument. A composite handle for the composite instrument is provided comprising a first handle and a second handle when the first handle is coupled with the second handle. The handle makes possible the reliable transmission, with increased mechanical advantage, of both torsional and longitudinal loads by the physician to the composite instrument, while resisting relative rotation between the first and second instruments. The instrument is sterilization sensitive, changing physical appearance after sterilization.

FIELD OF THE INVENTION

The invention generally relates to hand-held tools and instruments and to procedures that deploy these instruments through tissue to access interior regions of the body.

BACKGROUND OF THE INVENTION

There are many different types and styles of hand-held surgical instruments that physicians use to gain access into interior body regions. These instruments are intended to penetrate tissue by the application of pushing forces, twisting forces, or both in combination.

Often, a single surgical procedure will require the physician to employ different surgical instruments, each possessing a different shape, size, and function. Often, the procedure will require the physician to deploy these instruments in both soft and hard tissue to meet the diagnostic or therapeutic objectives of the procedure. The physician will often need an enhanced mechanical advantage to advance an instrument through tissue, particularly through dense or hard tissue, such as bone.

The common need to use different instruments in a given procedure, coupled with the need to accurately and reliably deploy each of these different instruments through both soft and hard tissue, often with an enhanced mechanical advantage, complicate the physician's already difficult task. The need to handle different instruments in different ways for different purposes can distract the physician and lead to wasted effort, which can lengthen the overall time of the procedure.

SUMMARY OF THE INVENTION

The invention provides a surgical instrument with a handle design that allows initial placement of both a cannula and a trocar into interior body regions, and allows for later withdrawal of the trocar while leaving the cannula in place. The invention obviates the need for several instruments during surgical procedures, and simplifies interior access protocol. At the same time, the handle of the surgical instrument makes possible the reliable transmission, with increased mechanical advantage, of both torsional and longitudinal loads by the physician to the selected instrument.

One aspect of the invention provides a tool comprising a first functional instrument having a first handle and a second functional instrument having a second handle. The first functional instrument engages the second functional instrument, forming a composite instrument. The first handle mates with the second handle, forming a composite handle for the composite instrument.

Features and advantages of the inventions are set forth in the following Description and Drawings, as well as in the appended Claims.

The invention may be embodied in several forms without departing from its spirit or essential characteristics. The scope of the invention is defined in the appended claims, rather than in the specific description preceding them. All embodiments that fall within the meaning and range of equivalency of the claims are therefore intended to be embraced by the claims.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

This Specification describes new instruments for penetrating tissue. This specification also describes systems and methods to treat bones using expandable bodies in conjunction with new instruments for penetrating tissue.

The use of expandable bodies to treat bones is generally disclosed in U.S. Pat. Nos. 4,969,888 and 5,108,404, which are incorporated herein by reference. Improvements in this regard are disclosed in U.S. patent application Ser. No. 08/188,224, filed Jan. 26, 1994; U.S. patent application Ser. No. 08/485,394, filed Jun. 7, 1995; and U.S. patent application Ser. No. 08/659,678, filed Jun. 5, 1996, which are each incorporated herein by reference.

The new instruments, systems and methods will be described with regard to the treatment of vertebral bodies. It should be appreciated, however, that the handle configuration, instruments, systems and methods so described are not limited in their application to vertebrae. The systems and methods are applicable to the treatment of diverse bone types. Additionally, the handle configuration could be used with instruments other than a trocar and a cannula.

I. The Instruments

FIG. 1shows a composite instrument10for penetrating tissue. The composite instrument10includes a first functional instrument20and a second functional instrument40, and a composite handle12comprising a first handle22and a second handle42. The composite handle12aids a physician in manipulating the composite instrument10, but a physician can also desirably use the first handle22to independently manipulate the first instrument20or the second handle42to independently manipulate the second instrument40during use.

The number and type of instruments20and40can vary.FIG. 1shows two representative instruments20and40, each having a different size and function. In a preferred embodiment, the first functional instrument20is a trocar instrument, and the second functional instrument40is a cannula instrument.

A. The Trocar Instrument

Referring toFIGS. 1–4, the first instrument20functions as a trocar instrument to penetrate tissue. A trocar30has a proximal end32and a distal end34. The distal end34is tapered to present a penetrating surface35. In use, the penetrating surface35is intended to penetrate soft tissue and/or bone in response to pushing and/or twisting forces applied by the physician at the first handle22, or the composite handle12.

The first handle22is coupled to the trocar30at the proximal end of the trocar32. As best seen inFIG. 6C, the proximal end32of the trocar30can be formed in a T-shape, with the first handle22being molded around the T-shaped end. This arrangement significantly increases the mechanical strength of the bond between the handle22and the trocar30, and allows significant longitudinal and torsional forces to be transmitted from the handle22to the trocar30without bond failure. Alternatively, with or without a T-shaped end, the proximal end32of the trocar30can be scored (indicated by scored region33inFIG. 6C) to increase the mechanical strength of the bond between the trocar30and the handle22, or various bonding adhesives could be used, with varying results.

The first handle22desirably includes a viewing window24, an alignment ridge receiver26, a handle bore receiver28, and a handle key36, the uses of which are described later.

In an alternative embodiment (seeFIG. 18), the trocar30includes an interior lumen21, which passes through the handle22and the body of the trocar30. The interior lumen21accommodates passage of a stylet and/or conventional spinal needle assembly23, to guide the deployment of the first instrument20, by itself or nested with the second instrument40(asFIG. 18shows), through soft tissue to a targeted bone treatment site.

B. The Cannula Instrument

The second instrument40functions as a cannula instrument or guide sheath, and includes a cannula50. The cannula50of the second instrument40is desirably somewhat larger in diameter than and not as long as the trocar30of the first instrument20. As best shown inFIGS. 1 and 2, the second instrument40includes an interior lumen44that extends through the instrument from its distal end54to its proximal end52. The interior lumen44is sized to accept the trocar30. The size of the interior lumen44desirably allows the second instrument40to slide and/or rotate relative to the first instrument20, and vice versa, as will be described in greater detail later.

The distal end54of the second instrument40presents an end surface60. In use, the end surface60of the second instrument40desirably presents a low-profile surface, which can penetrate soft tissue surrounding the first instrument20in response to pushing and/or twisting forces applied at the composite handle12or the second handle42.

The proximal end52is coupled with the second handle42. As best seen inFIG. 6D, the proximal end52of the cannula50desirably incorporates a flared and notched end “A” and a textured surface “B”, around which the second handle42is molded. The flared and notched end “A” and textured surface “B” serve to increase the mechanical strength of the bond between the cannula50and the second handle42, allowing significant longitudinal and torsional forces to be transmitted between the second handle42and cannula50without bond failure. As with the trocar30, however, alternative bonding methods such as scoring of the cannula50and/or the use of various adhesives could be employed, with varying results.

Extending from the interior lumen44at the proximal end52of the cannula50, the second handle42desirably includes a handle bore48, preferably co-circumferential with the cannula50. The second handle42includes an alignment ridge46, and a handle groove56, the uses of which are described later.

C. The Drill Bit Instrument

As shown inFIG. 11, an optional third functional instrument70functions as a drill bit. The drill bit instrument70, having a distal end72and a proximal end74, typically is slightly longer than and has generally the same physical dimensions as, the trocar30. Like the trocar30, the drill bit instrument70is intended, in use, to fit for sliding and rotational movement within the interior lumen44of the second instrument40.

The distal end72of the drill bit instrument70desirably includes cutting edges76. In use, the cutting edges76are intended to penetrate hard tissue in response to rotation and longitudinal load forces applied at the proximal end74of the drill bit instrument70.

The drill bit instrument70can be of known construction, and could vary widely. Desirably. the diameter of the drill bit instrument70is smaller than the interior lumen44of the second instrument40, and the length is longer than the cannula50, such that the drill bit instrument70can access tissue deeper than the cannula50when the cannula50is installed in a patient.

II. The Instrument Handles

The first handle22and the second handle42are designed to comfortably accommodate a hand, to desirably interlock to form a composite handle12that resists relative rotation between the first handle22and the second handle42, and desirably to indicate whether the instruments have been reused and/or resterilized.

A. Hand Accommodation

As shown inFIGS. 1–4, the composite handle12is shaped to be comfortably and securely grasped by a normal human hand as shown inFIG. 3. Preferably, the contours of the composite handle12are rounded to provide a comfortable grip and to minimize surgical glove tears.

As shown inFIG. 3, in the preferred embodiment, the first handle22is desirably equipped with two finger receivers38, intended to receive the index finger and the pinkie finger of a physician.

Shown inFIG. 4, in the preferred embodiment, the second handle42is desirably equipped with two finger receivers58, intended to receive the middle finger and the ring finger of a physician.

The shape and size of the first handle22and second handle42, of course, vary. In the embodiment shown inFIG. 1, the composite handle12, and in particular the first handle22, includes a striking plate14, elongated to fit comfortably across the palm of the hand. The striking plate14is also configured to receive a striking blow, described later.

In order to properly interact when applying striking, pushing and/or twisting forces to the composite handle12, the first handle22desirably will not rotate relative to the second handle42. Referring now toFIGS. 5,6A and6B, to avoid relative rotation, the first handle22preferably includes the alignment ridge receiver26to receive the alignment ridge46of the second handle42. Although described and pictured as a ridge, the alignment mechanism interaction between the first handle22and the second handle42could comprise any number of shapes other than an arcuate shape, for example a block shape or a star shape.

In use, when the trocar30of the first instrument20is slid through the cannula50of the second instrument40, the first handle22and second handle44can fit together to form the composite handle12. In addition to the alignment ridge46resisting rotation because of the alignment ridge receiver26, the first handle22can include a handle key36for coupling with the handle groove56of the second handle42.

If the handle groove56is not aligned with the handle key36, and thus the alignment ridge46not aligned with the alignment ridge receiver26, the handle bore48of the second handle42desirably will not fully insert into the handle bore receiver28of the first handle22. In this alignment, the viewing window24will display the trocar30, which preferably extends past the viewing window24. Also in this alignment, the first handle22is desirably able to rotate independently of the second handle42.

If, however, as shown inFIG. 6B, the handle groove56is aligned with the handle key36, and thus the alignment ridge46is aligned with the alignment ridge receiver26, the handle bore48of the second handle42can be fully inserted into the handle bore receiver28of the first handle22.

In this operational alignment, the viewing window24displays the handle bore48. Preferably, the handle bore48is a different color than the trocar30such that visualization would be simplified. Also in this alignment, the first handle22desirably does not rotate independently of the second handle42. In this alignment, the composite handle10is sized and shaped to accommodate four fingers, two fingers each on the first handle22and the second handle42.

Of course, its should be understood that the first and second handles22and42could be designed to engage in non-parallel orientations, such that the first and second handles22and42would not be parallel when properly engaged to form the composite handle10. For example, the first handle22could incorporate a star or hexagonal shaped opening, into which a corresponding star or hexagonal shaped second handle42could engage in a multiplicity of orientations.

In use, various forces resist relative motion between the first instrument20and the second instrument40. As shown inFIG. 3, when a hand grips the composite handle10, the upward force supplied by the fingers, coupled with the downward force supplied by the palm, will compress the first instrument20and the second instrument40together. As previously noted, when properly configured, relative rotation of the instruments is desirably constrained as well.

C. Handle Materials

The material chosen for the first handle22and the second handle42desirably provides sufficient structural integrity to withstand manual manipulation and forces expected from manual striking blows. The first handle22and the second handle42are made from a molded or cast rigid material sufficient in strength to withstand the striking, pushing and twisting forces without significant deformation.

Another preferable characteristic of the handle composition is that the first handle22and the second handle42can be roughened or otherwise textured to provide a secure gripping surfaces.

To encourage single use and discourage reuse and/or resterilization, it is preferable to differentiate between new hand tools and hand tools that have been reused and/or resterilized.

Striking and exertion of manual pressure on any of the instruments and structures described herein during first use generates stress on the material or materials which make up the instruments and/or structure. The material stress created by operational loads during first use can significantly alter the molded morphology of the structure, making future performance of the structure unpredictable.

For example, during advancement of the trocar and the cannula into the cancellous bone during a single use creates contact with surrounding cortical and cancellous bone. This contact can damage the structure, creating localized regions of weakness, which often can escape visual detection. The existence of localized regions of weakness can unpredictably cause structural failure during a subsequent use. Such contact can also cause flattening and/or curling of the end surface of the cannula, or dulling of the penetrating surface of the trocar.

In addition, exposure to blood and tissue during a single use can entrap biological components on or within the structure of the cannula or handles. Despite cleaning and subsequent sterilization, the presence of entrapped biological components can lead to unacceptable pyrogenic reactions.

As a result, following first use, the structure might not meet established performance and sterilization specifications. The effects of material stress and damage caused during a single use, coupled with the possibility of pyrogen reactions even after resterilization, reasonably justify and encourage single use for the instruments and handles that are deployed in tissue and bone.

To protect patients from the potential adverse consequences occasioned by multiple use, which include disease transmission, or material stress and instability, or decreased or unpredictable performance, various materials may be used to indicate and possibly prevent re-use and/or resterilization of the hand tools.

For example, a heat degradable material can be used to indicate, through deformation, whether a hand tool has been autoclaved. Additionally, chemical sensitive pigments, such as inks commercially available from Tempil, could be applied to the composite handle12to indicate, through a change of color, whether a hand tool has been chemically sterilized, for instance by use of ethylene oxide (ETO), as described in the requirements of ANSI/AAMI/ISO11135:1994 for sterilizing devices. In addition, various materials which change color and/or physical composition in the presence of other sterilization methods, such as radiation sterilization, can be incorporated into hand tools to indicate sterilization.

One material that provides sufficient structural rigidity and yet indicates whether an instrument has been exposed to heat common to sterilization is LUSTRAN™ material, which is commercially available from Bayer. As shown inFIGS. 17A and 17B, when this material is used in handle construction, the material will typically deform during heat sterilization, desirably preventing the handle groove56from aligning with the handle key36, and thus preventing the alignment ridge46from aligning with the alignment ridge receiver26. Additionally, following deformation, the handle bore48of the second handle42desirably cannot be fully inserted into the handle bore receiver28of the first handle22.

III. Illustrative Use of the System

The following describes use of the composite instrument10, instruments20,40, and70, in conjunction with a catheter component130, a diagnostic or therapeutic element132, a syringe136and a tamping instrument142as shown inFIGS. 9–15in the context of treating bones. This is because these items can be advantageously used for this purpose. Still, it should be appreciated that the composite instrument10is not limited to use in the treatment of bones, nor limited to instruments intended to contact tissue to perform a diagnostic or therapeutic function. The composite handle12configuration associating the first handle22and the second handle42can be used in association with various other hand-held instruments.

The composite instrument10, handles12,22, and42, and instruments20,40,64and70will now be described with regard to the treatment of human vertebra. It should be appreciated, however, their use is not limited to human vertebrae. The handle18can be used in association with hand-held instruments in the treatment of diverse human or animal bone types.

One use of the system is to treat vertebral bodies. AsFIG. 7Ashows, the spinal column80comprises a number of uniquely shaped bones, called the vertebrae82, a sacrum84, and a coccyx86(also called the tail bone). The number of vertebrae82that make up the spinal column80depends upon the species of animal. In a human (whichFIG. 7Ashows), there are twenty-four vertebrae82, comprising seven cervical vertebrae88, twelve thoracic vertebrae90, and five lumbar vertebrae92.

When viewed from the side, asFIG. 7Ashows, the spinal column80forms an S-shaped curve. The curve serves to support the head, which is heavy. In four-footed animals, the curve of the spine is simpler.

AsFIGS. 7A,7B and8show, each vertebra82includes a vertebral body96, which extends on the anterior (i.e., front or chest) side of the vertebra82. AsFIGS. 7A,7B and8show, the vertebral body96is in the shape of an oval disk. AsFIGS. 7B and 8show, the vertebral body96includes an exterior formed from compact cortical bone98. The cortical bone98encloses an interior volume100of reticulated cancellous, or spongy, bone102(also called medullary bone or trabecular bone). A “cushion,” called an intervertebral disk104, is located between adjacent vertebral bodies96.

An opening, called the vertebral foramen106, is located on the posterior (i.e., back) side of each vertebra82. The spinal ganglion109pass through the foramen106. The spinal cord108passes through the spinal canal107.

The vertebral arch110surrounds the spinal canal107. The pedicles112of the vertebral arch110adjoin the vertebral body96. The spinous process114extends from the posterior of the vertebral arch110, as do the left and right transverse processes116.

In a typical procedure, a patient lies on an operating table, while the physician introduces the composite instrument10into soft tissue (designated S inFIG. 9) in the patient's back. The patient can lie face down on the table, or on either side, or at an oblique angle, depending upon the physician's preference. Moreover, the procedure can be performed through an open anterior procedure or an endoscopic anterior procedure.

Under radiologic or CT monitoring, the physician advances the composite instrument10through soft tissue S down to and into the targeted vertebra82, asFIG. 9shows. The physician will typically administer a local anesthetic, for example, lidocaine, to the targeted region. In some cases, the physician may prefer other forms of anesthesia, such as general anesthesia.

As shown inFIG. 10, the physician directs the composite instrument10such that the trocar30of the first instrument20and the cannula50of the second instrument40penetrate the cortical bone98and the cancellous bone102of the targeted vertebra82. If desired, the physician twists the composite handle10while applying longitudinal force to the handle10. In response, the penetrating surface35of the trocar30, and the end surface60of the cannula50rotate and penetrate soft tissue and/or bone.

Preferably the depth of penetration of the distal end34of the trocar30and the end surface60of the cannula50are through a first wall of the cortical bone98and into the cancellous bone102. However, if the penetration through the first wall of the cortical bone98and into the cancellous bone102is not achievable by manual advancement of the composite instrument10, a physician can continue penetration by gently striking the striking plate14with a blunt instrument such as a surgical hammer (not shown), or otherwise applying appropriate additional longitudinal force to the composite handle12, to advance the distal end34of the trocar30and the end surface60of the cannula50.

If desired, the physician can utilize a spinal needle assembly and stylet to initially access the vertebral body82, and then utilize the alternative embodiment shown inFIG. 18to complete the access procedure. The embodiment shown inFIG. 18allows the physician to place a stylet23into the targeted vertebral body82, and then guide the composite instrument10through soft tissue and into the targeted vertebra body82along the stylet23, which passes through the trocar lumen21as the composite instrument10is advanced through soft tissue and into the vertebral body82. Once the trocar30has sufficiently penetrated cortical bone, the physician can withdraw the spinal needle assembly23.

After penetrating the cortical bone98, if desired, the physician may continue advancing the composite instrument10through the cancellous bone102of the vertebral body96, thereby forming a passage through the cancellous bone102. Preferably this passage will extend no more than 95% across the vertebral body. The physician may then withdraw the instrument10, such that the cannula50remains within the cortical bone98and/or extends only part-way into the cancellous bone102. The trocar30may then be withdrawn from the cannula50, allowing access to the passage formed in the interior of the vertebral body82through the cannula50.

Alternatively, after penetrating the cortical bone98, the physician may choose to withdraw the trocar30from the cannula50and form a passage in the cancellous bone102using a drill bit70. In such a case, the physician removes the first functional instrument20by holding the second instrument40in place and manually withdrawing the first instrument20.

Next, as shown inFIG. 11, the physician advances the drill bit70through the cannula50. Under X-ray control (or using another external visualizing system), the physician applies appropriate twisting and longitudinal forces to the drill bit70, to rotate and advance the cutting edge76of the drill bit70to open a passage through the bone tissue and completely into the cancellous bone102. The drilled passage preferably extends no more than 95% across the vertebral body96.

At this point in the procedure, access to the cancellous bone102has been accomplished and the end surface60of the cannula50extends into the interior volume100, leaving only the cannula instrument50in place.

2. Bone Treatment

As shown inFIG. 12, the physician can now acquire the catheter component130. The physician can advance the diagnostic or therapeutic element132carried by the catheter component130through the handle bore48and cannula50and into the interior volume100of the vertebral body96.

The distal diagnostic or therapeutic element132of the catheter component130can be configured to perform various functions. For example, the element132can comprise a biopsy instrument, to obtain samples of cancellous bone or to harvest bone marrow. Alternatively, the distal element132can be a stylet to introduce a medication or the like into cancellous bone. Still alternatively (as shown inFIG. 13), the distal element132can comprise an expandable body to compact cancellous bone102and form a cavity134in the vertebral body96, in the manner disclosed in U.S. Pat. Nos. 4,969,888, 5,108,404, and 5,827,289, which are incorporated herein by reference. Upon compaction of cancellous bone102, the distal element132can also include a nozzle140to inject a material into the formed cavity.

Upon formation of the cavity134, the physician acquires a syringe136and injection nozzle140. AsFIG. 14shows, the nozzle140is sized to pass through the cannula50, to thereby pass into the cavity134. The nozzle140connects by a threaded connector186to a syringe136. The nozzle140can be formed from a rigid metal material, e.g., stainless steel.

AsFIG. 14shows, the physician fills the syringe136with the desired volume of filling material138. The physician attaches the nozzle140to the filled syringe136. The physician inserts the nozzle140a selected distance beyond the distal end54of the cannula50and into the cavity, guided by markings166on the nozzle140. Next, the physician operates the syringe136to expel the material138through the nozzle140into the cavity134.

Desirably, the physician first introduces the material138into the region of the cavity134farthest from the distal end54of the cannula54. The physician successively draws the nozzle140toward the distal end54of the cannula50, while injecting the material138, to fill the remainder of the cavity54.

At this stage, the nozzle180is unthreaded from the syringe104. AsFIG. 15shows, the physician next advances a tamping instrument142through the nozzle140. The distal end of the tamping instrument142contacts the residual volume of material138in the nozzle140. Advancement of the tamping instrument142displaces the residual material138from the nozzle140, forcing it into the cavity134. The flow of material138into the cavity134, propelled by the advancement of the tamping instrument142in the nozzle140serves to uniformly distribute and compact the material138inside the cavity134, without the application of undue pressure.

As shown inFIG. 16, as an alternative to attaching the nozzle140to the syringe136, the physician can attach the syringe136directly to the handle bore48of the second instrument40. As shown in the alternate embodiment inFIG. 16, the syringe136can have threads137or other fasteners, such as snap-sit fasteners or luer-lock fasteners. The threads137would match with bore threads49contained in the handle bore48. Next, the physician operates the syringe136to expel the material138through the handle bore48and the cannula50and directly into the cavity134. In this arrangement, the physician disconnects the syringe136and advances the tamping instrument142through the handle bore48and the cannula50to displace the residual material138from the cannula50, forcing it into the cavity134.

The use of the syringe136with or without nozzle140, and the tamping instrument142allows the physician to exert precise control when filling the cavity134with material138. The physician can immediately adjust the volume and rate of delivery according to the particular local physiological conditions encountered. The application of low pressure (i.e., desirably no greater than 360 psi at the distal end of the cannula, more desirably no greater that 190 psi at the distal end of the cannula, and most desirably no greater than 100 psi at the distal end of the cannula), which is uniformly applied by the tamping instrument142, allows the physician to respond to fill volume, flow resistance, and flow path conditions quickly. The chance of overfilling and leakage of material138outside the cavity portion is thereby significantly reduced.

When the physician is satisfied that the material138has been amply distributed inside the cavity portion, the physician withdraws the tamping instrument142from the cannula50and handle bore48. The physician preferably first twists the tamping instrument142to cleanly break contact with the material138.

Of course, this procedure could be repeated to access and treat one vertebral body multiple times in multiple orientations to create multiple cavities that may or may not interconnect. After a cavity has been filled and tamped in the above described manner, the instruments can be withdrawn and the incision sites sutured closed. The bone treatment procedure is concluded.

C. Suggested Materials

Desirably, the material138will provide sufficient support within the vertebral body to prevent further fracture of the body. The capability of the vertebral bodies to withstand loads will have thereby been improved. The material may also facilitate healing of the vertebral body.

The selected material138can be a bone cement, or autograft or allograft bone graft tissue collected in conventional ways, e.g., in paste form (see Dick, “A Use of the Acetabular Reamer to Harvest Autogenic Bone Graft Material: A Simple Method for Producing Bone Paste,”Archives of Orthopaedic and Traumatic Surgery(1986), 105: 235–238), or in pellet form (see Bhan et al, “A Percutaneous Bone Grafting for Nonunion and Delayed Union of Fractures of the Tibial Shaft,”@International Orthopaedics(SICOT) (1993) 17: 310–312). Alternatively, the bone graft tissue can be obtained using a Bone Graft Harvester, which is commercially available from SpineTech. Using a funnel, the paste or pellet graft tissue material is loaded into the cannula50. The tamping instrument142is then advanced into the cannula50in the manner previously described, to displace the paste or pellet graft tissue material out of the cannula50and into the cavity134.

The selected material138can also comprise a granular bone material harvested from coral, e.g., ProOsteon™ calcium carbonate granules, available from Interpore. The granules are loaded into the cannula50using a funnel and advanced into the cavity using the tamping instrument142.

The selected material138can also comprise demineralized bone matrix suspended in glycerol (e.g., Grafton™ allograft material available from Osteotech), or SRS™ calcium phosphate cement available from Novian. These viscous materials, like the bone cement previously described, can be loaded into the syringe136and injected into the cavity directly or using the nozzle140, which is inserted through the cannula50into the cavity134. The tamping instrument142is used to displace residual material from the cannula50into the cavity134, as before described.

The selected material138can also be in sheet form, e.g. Collagraft™ material made from calcium carbonate powder and collagen from bovine bone. The sheet can be rolled into a tube and loaded by hand into the cannula50. The tamping instrument142is then advanced through the cannula50, to push and compact the material in the cavity134.

The features of the invention are set forth in the following claims.