TISSUE PROTECTOR AND METHOD OF USE
A tissue protector has a body structure having a longitudinal extending thin web. The body structure has an unconstrained first shape configured to form a nerve shield and is configured to shrink about a longitudinal axis to a smaller constrained second shape sized to fit into a lumen of a cannula. Preferably, the second constrained shape is oval or round having a maximum diameter equal or less than an inside diameter of the lumen. The body structure is configured to return to the first shape when the cannula is withdrawn or returned to this shape as the implant advances.
The present application is a continuation of U.S. patent application Ser. No. 16/166,277 filed Oct. 22, 2018, which is a division of U.S. patent application Ser. No. 14/525,880 filed on Oct. 28, 2014, now U.S. Pat. No. 10,136,958 issued Nov. 27, 2018, the disclosure of each of which is incorporated by reference herein in its entirety.
TECHNICAL FIELDThe present invention relates to a tissue protector, or in this particular example, a tissue and nerve shield for use in minimally invasive spinal surgery.
BACKGROUND OF THE INVENTIONWhen a surgeon is accessing a region to be repaired such as the disc space between adjacent vertebrae, great care must be taken to avoid injury to the exposed nerve root.
Dural tears, nerve root damage, bleeding and infection, operating on the wrong level or on the wrong side are as real issues in all spinal surgeries.
With thoracic approaches, pneumothorax is also a possibility.
In addition, some injuries may be underestimated or even go unnoticed, such as a dural tear under the low-pressure irrigation.
It is an objective of the present invention to further minimize the potential for such complications by providing a unique protective tissue protector or nerve shield made in accordance to the invention as disclosed herein.
SUMMARY OF THE INVENTIONA tissue protector or nerve shield has a body structure having a longitudinal extending thin web. The body structure has an unconstrained first shape configured to form a nerve shield and is configured to shrink about a longitudinal axis to a smaller constrained second shape sized to fit into a lumen of a cannula. Preferably, the second constrained shape is oval or round having a maximum diameter equal or less than an inside diameter of the lumen. The body structure is configured to return to the first shape when the cannula is withdrawn from between two adjacent vertebral bodies and the body structure is held in position between the vertebral bodies.
The web is configured to shield a nerve root and the surrounding tissue. Also, the unconstrained first shape of the web is sized to receive a spinal implant for insertion between the two vertebral bodies. The web forms a guide and a shield for the spinal implant. The web can have a thin oval or circular cross section in the unconstrained first shape. Alternatively, the web can have a channel or “U” cross section, rectangular or triangular cross section in the unconstrained first shape.
In a preferred embodiment, the body structure further has a pair of rails on each lateral end or side of the web, the web being interposed between said rails. The nerve shield when unconstrained has at least one rail shielding a nerve root. The rails are spaced by the web, when the body structure is in the unconstrained first shape, a lateral distance or width to receive a spinal implant or surgical instrument. The pair of rails is configured to guide a spinal implant during insertion while at least one of said rails shields the nerve root or tissue of interest. The rails are enlarged longitudinally extending projections having a round or at least partially round cross section. The web can be a thin rectangular cross section in the unconstrained first shape.
The invention permits a method of shielding a nerve root or tissue of interest during a spinal surgical procedure having the steps of: making an incision; inserting a cannula, wherein the cannula has a shield constrained inside the lumen of the cannula; positioning the distal end of the cannula past or beside a nerve root or tissue; withdrawing the cannula while holding the shield in position past or beside the nerve root or tissue; and freeing the shield allowing movement from a constrained shape to an unconstrained shape to protect and shield the nerve root or tissue. The method further can include inserting a spinal implant using the unconstrained shield as a guide to position the implant between two vertebral bodies.
The invention will be described by way of example and with reference to the accompanying drawings in which:
With reference to the drawings
A unique feature of the present invention tissue protector 10 is that it is provided with a very thin web 12 as shown in
With reference to
While the implant 100 is shown on the flat web 12 of the body structure 11, it is appreciated that the spinal implant 100 similarly could be placed within the unconstrained first shapes of the other alternative embodiments having either a simple thin web 12 without any enlarged projections 14, shown in 6A, wherein the implant can be positioned inside the unconstrained first shape after the nerve shield 10 has been freed of the cannula 20 or similarly can be placed inside the other alternatives shown in
Alternatively, the implant can help or cause the tissue protector to achieve unconstrained final shape. So, as the implant advances, the tissue protector goes from constrained to unconstrained.
With reference to
With reference to
Since this is only one of the shapes that the tissue protector 10 can take, the alternative embodiments show variations in that shape. The thickness of the web 12 will be adapted to any size necessary to achieve an adequate wrapping. The primary objective is to ensure that the tissue protector 10 can be sufficiently constrained to fit easily and be held easily in a cannula 20 having an 8.5 mm diameter by way of example. Larger and smaller diameter cannulas could be used.
Variations in the present invention are possible in light of the description of it provided herein. While certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in this art that various changes and modifications can be made therein without departing from the scope of the subject invention. It is, therefore, to be understood that changes can be made in the particular embodiments described, which will be within the full intended scope of the invention as defined by the following appended claims.
Claims
1. A tissue protector comprises:
- a body structure having a longitudinal extending thin web, the body structure having an unconstrained first shape configured to form a tissue protector and is configured to shrink about a longitudinal axis to a smaller constrained second shape sized to fit into a lumen of a cannula.
2. The body structure of claim 1 wherein the second constrained shape is oval or round having a maximum diameter equal or less than an inside diameter of the lumen.
3. The tissue protector of claim 1 wherein the body structure is configured to return to the first shape when the cannula is withdrawn from between two adjacent vertebral bodies and the body structure is held in position.
4. The tissue protector of claim 3 wherein the web is configured to shield a nerve root.
5. The tissue protector of claim 4 wherein the unconstrained first shape of the web is sized to receive a spinal implant for insertion between the two vertebral bodies.
6. The tissue protector of claim 5 wherein the web forms a guide and a shield for the spinal implant.
7. The tissue protector of claim 6 wherein the web has a thin oval or circular cross section in the unconstrained first shape.
8. The tissue protector of claim 6 wherein the web has a channel or “U” cross section in the unconstrained first shape.
9. The body structure of claim 1 further comprises:
- a pair of rails on each lateral end or side of the web, the web being interposed between said rails.
10. The body structure of claim 9 wherein the body structure is configured to return to the first shape when the cannula is withdrawn from between two adjacent vertebral bodies and the body structure is held in position.
11. The tissue protector of claim 5 wherein the rails when unconstrained have at least one rail shielding a nerve root.
12. The tissue protector of claim 6 wherein the rails are spaced by the web when the body structure is in the unconstrained first shape a lateral distance to receive a spinal implant.
13. The tissue protector of claim 7 wherein the pair of rails are configured to guide a spinal implant during insertion while at least one of said rails shields the nerve root.
14. The body structure of claim 9 wherein the rails are enlarged longitudinally extending projections.
15. The body structure of claim 14 wherein the rails have a round or at least partially round cross section.
16. The tissue protector of claim 12 wherein the rails have a round or at least partially round cross section.
17. The tissue protector of claim 12 wherein the web has a thin rectangular cross section in the unconstrained first shape.
18. A method of shielding a nerve root during a spinal surgical procedure comprises the steps of:
- making an incision;
- inserting a cannula between or just above two adjacent vertebral bodies, wherein the cannula has a tissue protector constrained inside the lumen of the cannula;
- positioning the distal end of the cannula past or beside a nerve root;
- withdrawing the cannula while holding the tissue protector in position past or beside the nerve root; and
- freeing the tissue protector allowing movement from a constrained shape to an unconstrained shape to protect and shield the nerve root.
19. The method of claim 18 further comprising:
- inserting a spinal implant using the unconstrained tissue protector as a guide to position the implant between two vertebral bodies.
Type: Application
Filed: Aug 23, 2021
Publication Date: Dec 9, 2021
Inventor: Zsolt Csernatoni (Woodstock, GA)
Application Number: 17/408,856