Method and apparatus for controlled contraction of soft tissue
An apparatus and method are provided for control contraction of tissue that includes collagen fibers. The apparatus includes a handpiece, and an electrode with an electrode proximal end associated with the handpiece. A distal end of the electrode has a geometry that delivers a controlled amount of energy to the tissue for a desired contraction of the collagen fibers. This is achieved while dissociation and breakdown of the collagen fibers is minimized. The handpiece, with electrode, is adapted to be introduced through an operating cannula in percutaneous applications. Additionally, an operating cannula may be included in the apparatus and be attached to the handpiece. The apparatus and method provides for a desired level of contraction of collagen soft tissue without dissociation or breakdown of collagen fibers.
This application is a continuation of U.S. application Ser. No. 09/664,473, filed Sep. 18, 2000, which is a continuation of U.S. application Ser. No. 08/696,051, filed Aug. 13, 1996, which is a continuation-in-part of U.S. application Ser. No. 08/637,095, filed Apr. 24, 1996, now U.S. Pat. No. 6,482,204, which is a continuation of U.S. application Ser. No. 08/389,924, filed Feb. 16, 1995, now U.S. Pat. No. 5,569,242, which is a continuation of Ser. No. 08/238,862, filed May 6, 1994, now U.S. Pat. No. 5,458,596.
BACKGROUND OF THE INVENTION1. Field of the Invention
This invention relates generally to the contraction of soft tissue, and more particularly, to the compaction of soft collagen tissue with minimal dissociation of collagen tissue.
2. Description of the Related Art
Instability of peripheral joints has long been recognized as a significant cause of disability and functional limitation in patients who are active in their daily activities, work or sports. Diarthrodial joints of musculoskeletal system have varying degrees of intrinsic stability based on joint geometry and ligament and soft tissue investment. Diarthrodial joints are comprised of the articulation of the ends of bones and their covering of hyaline cartilage surrounded by a soft tissue joint capsule that maintains the constant contact of the cartilage surfaces. This joint capsule also maintains within the joint the synovial fluid that provides nutrition and lubrication of the joint surfaces. Ligaments are soft tissue condensations in or around the joint capsule that reinforce and hold the joint together while also controlling and restricting various movements of the joints. The ligaments, joint capsule, and connective tissue are largely comprised of collagen.
When a joint becomes unstable, its soft tissue or bony structures allow for excessive motion of the joint surfaces relative to each other and in directions not normally permitted by the ligaments or capsule. When one surface of a joint slides out of position relative to the other surface, but some contact remains, subluxation occurs. When one surface of the joint completely disengages and loses contact with the opposing surface, a dislocation occurs. Typically, the more motion a joint normally demonstrates, the more inherently loose the soft tissue investment is surrounding the joint. This makes some joints more prone to instability than others. The shoulder, (glenohumeral) joint, for example, has the greatest range of motion of all peripheral joints. It has long been recognized as having the highest subluxation and dislocation rate because of its inherent laxity relative to more constrained “ball and socket” joints such as the hip.
Instability of the shoulder can occur congenitally, developmentally, or traumatically and often becomes recurrent, necessitating surgical repair. In fact subluxations and dislocations are a common occurrence and cause for a large number of orthopedic procedures each year. Symptoms include pain, instability, weakness, and limitation of function. If the instability is severe and recurrent, functional incapacity and arthritis may result. Surgical attempts are directed toward tightening the soft tissue restraints that have become pathologically loose. These procedures are typically performed through open surgical approaches that often require hospitalization and prolonged rehabilitation programs.
More recently, endoscopic (arthroscopic) techniques for achieving these same goals have been explored with variable success. Endoscopic techniques have the advantage of being performed through smaller incisions and therefore are usually less painful, performed on an outpatient basis, are associated with less blood loss and lower risk of infection and have a more cosmetically acceptable scar. Recovery is often faster postoperatively than using open techniques. However, it is often more technically demanding to advance and tighten capsule or ligamentous tissue arthroscopically because of the difficult access to pathologically loose tissue and because it is very hard to determine how much tightening or advancement of the lax tissue is clinically necessary. In addition, fixation of advanced or tightened soft tissue is more difficult arthroscopically than through open surgical methods.
Collagen connective tissue is ubiquitous in the human body and demonstrates several unique characteristics not found in other tissues. It provides the cohesiveness of the musculoskeletal system, the structural integrity of the viscera as well as the elasticity of integument. These are basically five types of collagen molecules with Type I being most common in bone, tendon, skin and other connective tissues, and Type III is common in muscular and elastic tissues.
Intermolecular cross links provide collagen connective tissue with unique physical properties of high tensile strength and substantial elasticity. A previously recognized property of collagen is hydrothermal shrinkage of collagen fibers when elevated in temperature. This unique molecular response to temperature elevation is the result of rupture of the collagen stabilizing cross links and immediate contraction of the collagen fibers to about one-third of their original lineal distention. Additionally, the caliber of the individual fibers increases greatly, over four fold, without changing the structural integrity of the connection tissue.
There has been discussion in the existing literature regarding alteration of collagen connective tissue in different parts of the body. One known technique for effective use of this knowledge of the properties of collagen is through the use of infrared laser energy to effect tissue heating. The use of infrared laser energy as a corneal collagen shrinking tool of the eye has been described and relates to laser keratoplasty, as set forth in U.S. Pat. No. 4,976,709. The importance controlling the localization, timing and intensity of laser energy delivery is recognized as paramount in providing the desired soft tissue shrinkage effects without creating excessive damage to the surrounding non-target tissues.
Radiofrequency (RF) electrical current has been used to reshape the cornea. Such shaping has been reported by Doss in U.S. Pat. Nos. 4,326,529; and 4,381,007. However, Doss was not concerned with dissociating collagen tissue in his reshaping of the cornea.
Shrinkage of collagen tissue is important in many applications. One such application is the shoulder capsule. The capsule of the shoulder consists of a synovial lining and three well defined layers of collagen. The fibers of the inner and outer layers extend in a coronal access from the glenoid to the humerus. The middle layer of the collagen extends in a sagittal direction, crossing the fibers of the other two layers. The relative thickness and degree of intermingling of collagen fibers of the three layers vary with different portions of the capsule. The ligamentous components of the capsule are represented by abrupt thickenings of the inner layer with a significant increase in well organized coarse collagen bundles in the coronal plane.
The capsule functions as a hammock-like sling to support the humeral head. In pathologic states of recurrent traumatic or developmental instability this capsule or pouch becomes attenuated and the capsule capacity increases secondary to capsule redundance. In cases of congenital or developmental multi-directional laxity, an altered ratio of type I to type III collagen fibers may be noted. In these shoulder capsules a higher ratio of more elastic type III collagen has been described.
There is a need for a method and apparatus to effect controlled lineal contraction or shrinkage of collagen fibers to provide a multitude of non-destructive and beneficial structural changes and corrections within the body. More particularly with regard to the shoulder capsule, current surgical techniques involve cutting or advancing the shoulder capsule to eliminate capsular redundance or to otherwise tighten the ligamous complex. Accordingly, there is a need to control shrinkage of the capsule by utilizing the knowledge of the properties of collagen in response to a specific level of thermal application.
SUMMARY OF THE INVENTIONIt is an object of the present invention to provide a method and apparatus to control the duration and application of thermal energy to a tissue site made that includes collagen soft tissue, a desired level of contraction of collagen fibers is obtained while dissociation and breakdown of the collagen fibers is minimized.
Another object of the present invention is to use RF heating in a fluid environment to control thermal spread to a tissue that includes collagen soft tissue, and a desired contraction of collagen fibers is obtained while minimizing dissociation and breakdown of the collagen fibers.
Yet another object of the present invention is to provide a device directed to collagen connective tissue shrinkage by the use of RF heating to a temperature profile of 43 to 90 degrees centigrade.
Another object of the present invention is to provide a device directed to collagen connective tissue shrinkage by the use of RF heating to a temperature profile of 43 to 75 degrees centigrade.
Still a further object of the present invention is to provide a device directed to collagen connective tissue shrinkage by the use of the RF heating to a temperature profile of 45 to 60 degrees centigrade.
Another object of the present invention is to provide an apparatus which delivers RF energy through an endoscopically guided handpiece in a fluid environment to obtain maximum contraction of collagen soft tissue while minimizing dissociation and breakdown of the collagen tissue.
Yet another object of the present invention is to provide an apparatus that provides for the maximum amount of collagen contraction without dissociation of the collagen structure.
Another object of the present invention is to provide an apparatus to deliver a controlled amount of RF energy to the collagen soft tissue of a joint in order to contract and restrict the soft tissue elasticity and improve joint stability.
A further object of the present invention to provide an apparatus and method that reduces redundancy of the shoulder capsule and improves stability to the joint.
These and other objects of the invention are obtained with an apparatus for control contraction of tissue that includes collagen fibers. The apparatus include a handpiece, and an electrode with an electrode proximal end that is associated with the handpiece. A distal end of the electrode has a geometry that delivers a controlled amount of energy to the tissue in order to achieve a desired contraction of the collagen fibers. This is achieved while dissociation and breakdown of the collagen fibers is minimized.
The handpiece, with electrode, is adapted to be introduced through an operating cannula in percutaneous applications. Additionally, it may be desirable to include as part of the apparatus an operating cannula. In this instance, the operating cannula has a proximal end that attaches to the handpiece, and a distal end that is adapted to be introduced into a body structure. The electrode is positioned within the operating cannula, and extendable beyond the distal end of the cannula when thermal energy is delivered to the tissue.
It is recognized that the delivery of the thermal energy to the tissue should be delivered in such a way that none of the tissue is ablated. Additionally, the delivery is achieved without dissociating or breaking down the collagen structure. This can be accomplished in different ways, but it has been discovered that an electrode with radiused edges at its distal end is suitable to obtain this result. The present invention is applicable to a number of different anatomical sites. Depending on the anatomy, it may be necessary to deflect the distal end of the electrode to reach the desired site. Additionally, one side of the electrode may include an insulating layer so that thermal energy is only delivered to the intended tissue, and not a tissue in an adjacent relationship to the area of treatment.
In certain instances it is desirable to be able to vary the length of the electrode conductive surface which delivers the thermal energy to the tissue. For this purpose, an adjustable insulator, that is capable of movement along the longitudinal axis of the electrode, provides a way of adjusting the length of electrode conductive surface.
Memory metals can be used for the electrode construction. An advantage of memory metals is that with the application of heat to the metal, it can be caused to be deflected. This is particularly useful for deflecting the distal end of the electrode.
The electrode can include a central lumen that receives an electrolytic solution from an electrolytic source. A plurality of apertures are formed in the distal end of the electrode and deliver the flowing electrolytic fluid to the tissue. Instead of an electrolytic solution, an electrolytic gel can also be introduced through the electrode.
In one embodiment of the invention, the electrode is partially surrounded by an insulating housing in order to position the electrode in an adjacent but spaced relationship to the tissue. A portion of the insulating housing rides on the tissue, and creates the equivalent of a partial dam for electrolytic solution introduced through the electrode and towards the tissue. A cuff is disposed about the insulating housing. The cuff and insulating housing together create a return electrolytic solution channel for the removal of solution flowing out of the dam and away from the tissue site.
The handpiece of the invention can be connected, with a cable, to an RF energy source. A closed loop feedback system can be included and coupled to a temperature sensor on the electrode and the RF energy source. Temperature at the electrode can be monitored, and the power of the RF energy source adjusted to control the amount of energy that is delivered to the tissue.
The present invention has wide spread application to many different anatomical locations. It can be utilized for controlled contraction of collagen soft tissue of a joint capsule, particularly the gleno-humoral joint capsule of the shoulder, to treat herniated discs, the meniscus of the knee, for dermatology, to name just a few.
In one embodiment of the invention, RF heating in a fluid or saline environment is used to control thermal spread to soft collagen tissue. The RF energy can be delivered through an endoscopically guided handpiece under arthroscopic visualization by the surgeon. In the temperature range of 43 to 90 degrees C., maximum collagen contraction is achieved. Additional temperature ranges are 43 to 75 degrees C., and 45 to 60 degrees C. Lower temperatures do not provide maximum thermal induced contracture of the collagen fibrils. Greater temperatures create excessive destruction and disintegration of the collagen fibrillar pattern. Thus, the present invention is a method and apparatus which accurately controls the application of heat within a desired thermal range. This heat is delivered the collagen soft tissue, thereby contracting and restricting the soft tissue elasticity and improving stability.
DESCRIPTION OF THE DRAWINGS
Referring now generally to
Electrode 14 can have be a flat elongated structure that is easily painted across a tissue without “hanging up” on any section of the tissue. In one geometry of electrode 14, all edges 20 of distal end 18 are radiused, as illustrated in
Apparatus 10, comprising handpiece 12 and electrode 14, is adapted to be introduced through an operating cannula for percutaneous applications. It will be appreciated that apparatus 10 may be used in non-percutaneous applications and that an operating cannula is not necessary in the broad application of the invention.
As illustrated in
Operating cannula 24 has a proximal end that attaches to handpiece 12 and it can have a sharp or piercing distal end 26 that pierces a body structure in order to introduce electrode 14 to a desired site. Electrode 14 is positioned within an interior lumen of operating cannula 24 and is extendable beyond distal end 26 in order to reach the desired tissue site. Electrode 14 can be advanced and retracted in and out of operating cannula 24 by activating a deployment button 28 which is located on the exterior of handle 12. Deployment button 28 is preferably activated by the operator merely by sliding it, which causes electrode 14 to advance in a direction away from distal end 26 of operating cannula 24. Deployment button 28 can be pulled back, causing a retraction of electrode 14 towards distal end 26. In many instances, electrode 14 will be retracted to be positioned entirely within operating cannula 14. Electrode 14 can also deployed with fluid hydraulics, pneumatics, servo motors, linear actuators, and the like.
An electrical and/or fluid flow cable 28 attaches to handle 12 and provides the necessary connection of apparatus 10 to a suitable energy source and/or a source of fluid, which may be an electrolytic solution or an electrolytic gel. An electrolytic solution, for purposes of this invention, is one that increases the transfer of thermal energy from electrode 14 to a tissue. Suitable electrolytic solutions include but are not limited to saline solution and the like.
A variety of energy sources can be used with the present invention to transfer thermal energy to the tissue that includes collagen fibers. Such energy sources include but are not limited to RF, microwave, ultrasonic, coherent light and thermal transfer.
When an RF energy source is used, the physician can activate the energy source by the use of a foot switch 30 that is associated with handle 12 and electrode 14. Significantly, a controlled amount of RF energy is delivered so that there is an effective transfer of thermal energy to the tissue site so that the thermal energy spreads widely through the tissue but does not cause a dissociation or breakdown of the collagen fibers.
For many applications, it is necessary to have electrode distal end 18 to become deflected (
As shown in
Electrode 14 can be tubular in nature with a central lumen. Electrode distal end 18 can include a conductive plug that is sealed to electrode distal end 18 by welding, e-beam, laser, and the like.
In
A plurality of apertures 42 are formed in electrode 14 to introduce a flowing fluid 44 through an interior lumen of electrode 14 and to the tissue site. The flowing fluid can be an electrolytic solution or gel, including but not limited to saline. The electrolyte furnishes an efficient electrical path and contact between electrode 14 and the tissue to be heated.
Referring now to
Cuff 50 and insulating housing 46 are closely positioned to each other, but they are spaced in a manner to create a return electrolytic solution channel 52. The used electrolyte solution may either be released within a confined body area, such as the joint, or not be returned to the tissue, but instead is removed.
Use of a cooled solution to deliver the thermal energy to the tissue, instead of direct contact with conductive surface 40, provides a more even thermal gradient in the tissue. Avoidance of surface overheating can be accomplished. There is a more uniform level of thermal energy applied to the tissue. Electrolytic solution 44 may be cooled in the range of about 30 to 55 degrees C.
Referring now to
The area of electrode 14 that serves as conductive surface 44 can be adjusted by the inclusion of an insulating sleeve 64 (
Electrode 14 can have a variety of different geometric configurations. In one embodiment, electrode 14 has an oval cross section (
As illustrated in
Referring now to
Additionally, the apparatus of the present invention can be an RF energy delivery device to effect contraction of collagen soft tissue while minimizing dissociation or breakdown of the collagen fibers. As shown in
Optionally positioned on electrode distal end 18 is a conductive roller element 76 (
The present invention provides a method of contracting collagen soft tissue. The collagen soft tissue is contracted to a desired shrinkage level without dissociation and breakdown of the collagen structure. It can be used in the shoulder, spine, cosmetic applications, and the like. It will be appreciated to those skilled in the art that the present invention has a variety of different applications, not merely those specifically mentioned in this specification. Some specific applications include joint capsules, specifically the gleno-humoral joint capsule of the shoulder, herniated discs, the meniscus of the knee, in the bowel, for hiatal hernias, abdominal hernias, bladder suspensions, tissue welding, DRS, and the like.
RF energy, thermal energy, is delivered to collagen soft tissue. The thermal energy penetrates more than 1 mm through the collagen soft tissue. The penetration can be as much as about 3 mm. Electrode 14 is painted across the collagen soft tissue sequentially until the maximum shrinkage occurs. In one embodiment, the collagen soft tissue is contracted in an amount of about two-thirds of its resting weight. A temperature range of about 43 to 90 degrees C. is preferred. More preferred, the temperature range is about 43 to 75 degrees C. Still more preferred is a temperature range of 45 to 60 degrees C.
In one specific embodiment of the invention, joint capsules are treated to eliminate capsular redundance. More specifically, the invention is utilized to contract soft collagen tissue in the gleno-humoral joint capsule of the shoulder. The basic anatomy of the gleno-humoral joint capsule of the shoulder is illustrated in
The apparatus of the present invention provides RF heating in a fluid or saline environment to control thermal spread. RF heating is applied to collagen connective tissue shrinkage in temperature ranges of about 43 to 90 degrees C., 43 to 75 degrees C. and 45 to 60 degrees C. The RF energy is delivered through endoscopically guided handpiece 12 in a fluid or saline environment within the joint. It can be under arthroscopic visualization by the surgeon, or the apparatus can include a viewing device. The invention accurately controls the application of heat within a specific thermal range, and delivers thermal energy to collagen soft tissue of the joint, thereby contracting and restricting the soft tissue elasticity and improving joint stability. When applied to the shoulder, there is capsular shrinkage of the gleno-humoral joint capsule of the shoulder and a consequent contracture of the volume, the interior circumference, of the shoulder capsule to correct for recurrent instability symptoms. The degree of capsular shrinkage is determined by the operating surgeon, based on severity of preoperative symptoms and condition of the capsule at the time of arthroscopic inspection. The maximum amount of collagen contraction achieved is approximately two-thirds of its original structure.
In
While embodiments and applications of this invention have been shown and described, it will be apparent to those skilled in the art that many more modifications than mentioned above are possible without departing from the invention concepts herein. The invention, therefore, is not to be restricted except in the spirit of the appended claims.
Claims
1. A method utilizing RF energy for a dermatological application, said method comprising:
- providing an apparatus comprising an RF energy source, a treatment device and at least one electrode coupled to the treatment device, said electrode having an electrode surface for delivering RF energy from the RF energy source;
- positioning the electrode surface on a skin surface;
- applying RF energy to a target tissue;
- heating the target tissue with RF energy while avoiding ablation of the target tissue; and
- contracting collagen fibers in the target tissue.
2. The method of claim 1 further comprising delivering a fluid to the skin surface such that the electrode surface is in contact with the fluid.
3. The method of claim 2 wherein the fluid is a gel.
4. The method of claim 2 wherein the fluid is a cooling fluid so as to minimize thermal damage to the skin surface.
5. The method of claim 1 wherein said applying RF energy comprises applying RF energy to a target tissue more than 1 mm below the skin surface.
6. The method of claim 1 wherein the RF energy source is coupled to the treatment device.
7. A method utilizing RF energy, said method comprising:
- providing an apparatus comprising an RF energy source, a treatment device and at least one electrode coupled to the treatment device, said electrode having an electrode surface for delivering RF energy from the RF energy source;
- positioning the electrode surface on a skin surface;
- applying RF energy to a target tissue;
- heating without significantly ablating the target tissue with RF energy such that the temperature of the target tissue does not exceed about 75° C.; and
- contracting collagen fibers in the target tissue to achieve a cosmetic effect.
8. A treatment method utilizing RF energy, said treatment method comprising:
- providing an apparatus comprising an RF energy source, a treatment device and at least one electrode coupled to the treatment device, said electrode having an electrode surface for delivering RF energy from the RP energy source;
- positioning the electrode surface on a tissue surface;
- applying RF energy to a target tissue below the tissue surface;
- heating the target tissue with RF energy while avoiding ablation of the target tissue; and
- contracting collagen fibers in the target tissue.
9. The treatment method of claim 8 wherein said heating the target tissue comprises heating the target tissue while completely avoiding ablation of the target tissue.
10. A method utilizing RF energy for a cosmetic application, said method comprising:
- providing an apparatus comprising an RF energy source, a treatment device and at least one electrode coupled to the treatment device, said electrode having an electrode surface for delivering RF energy from the RF energy source;
- delivering a fluid to a skin surface;
- positioning the electrode surface such that it is in contact with the fluid;
- delivering RF energy from the electrode surface to a target tissue below the skin surface; and
- heating the target tissue with RF energy to achieve at least one effect, said effect comprising contracted collagen fibers in the target tissue.
11. The method of claim 10 wherein said heating the target tissue comprises heating the target tissue with RF energy such that the temperature of the target tissue does not exceed about 90° C.
12. The method of claim 10 wherein the fluid is a gel.
13. The method of claim 10 wherein the fluid is a cooling fluid so as to minimize thermal damage to the skin surface.
14. A treatment method for applying RF energy to a target tissue without significantly ablating the target tissue, said treatment method comprising:
- providing a system having an RF energy source, a microprocessor, at least one electrode for delivering RF energy and a temperature sensor associated with the electrode;
- measuring the temperature of the electrode with the temperature sensor;
- providing the temperature of the electrode to the microprocessor; and
- determining whether to deliver RF energy from the electrode depending on the provided temperature.
15. A system for applying RF energy to treat tissue, said system comprising:
- an RF energy source; and
- a treatment device associated with the RF energy source, said treatment device comprising an electrically conductive material and a non-electrically conductive material,
- wherein the non-electrically conductive material is configured to extend along a surface of the tissue to be treated and to maintain the electrically conductive material from directly contacting the tissue.
16. The system of claim 15 wherein the non-electrically conductive material comprises at least one polymer.
17. The system of claim 16 wherein the at least one polymer is polyimide.
18. A system for contracting collagen fibers in a target tissue with RF energy from an RF energy source, said system comprising:
- an electrically conductive material for transmitting RF energy from the RF energy source; and
- a non-electrically conductive material wherein the non-electrically conductive material is configured between the electrically conductive material and the target tissue so as to maintain the electrically conductive material from directly contacting the target tissue.
19. A system for applying RF energy to a target tissue, said system comprising:
- an RF energy source; and
- a treatment device comprising an electrically conductive surface area for delivering RF energy from the RF energy source to the target tissue so as to contract collagen fibers in the target issue, wherein said treatment device is configurable to provide a plurality of surface areas.
20. A system for controllably contracting collagen fibers in a target tissue with RF energy to achieve a cosmetic effect, said system comprising:
- an RF energy source;
- a treatment device;
- at least one cable for connecting the RF energy source to the treatment device; and
- at least one electrode coupled to the treatment device, said electrode having an electrode surface configured to be positioned on a skin surface so as to deliver RF energy from the RF energy source to the target tissue while avoiding ablation of the target tissue.
21. The system of claim 20 further comprising a device for providing a cooling fluid so as to minimize thermal damage to the skin surface.
22. The system of claim 20 wherein the electrode surface is substantially planar.
23. A system for applying RF energy to a target tissue without significantly ablating the target tissue, said system comprising:
- an RF energy source;
- a handpiece;
- at least one cable for connecting the RF energy source to the handpiece;
- at least one electrode for delivering RF energy, said electrode coupled to the handpiece;
- a temperature sensor associated with the electrode, said temperature sensor configured to measure the temperature of the electrode; and
- a microprocessor configured to receive the temperature of the electrode from the temperature sensor and to determine whether to deliver RF energy from the electrode depending on the received temperature.
Type: Application
Filed: Feb 15, 2005
Publication Date: Mar 2, 2006
Inventors: Ronald Lax (Port Orange, FL), Gary Fanton (Portola Valley, CA), Stuart Edwards (Corral de Tierra, CA)
Application Number: 11/058,845
International Classification: A61F 7/00 (20060101); A61F 7/12 (20060101);