Devices and methods for percutaneous surgery

• US 6,162,170 A
• Filed: 01/20/1999
• Issued: 12/19/2000
• Est. Priority Date: 03/22/1996
• Status: Expired due to Term

• Current Assignee: SDGI Holdings Incorporated (Medtronic Plc)
• Original Assignee: SDGI Holdings Incorporated (Medtronic Plc)
• Inventors: Clayton, John B., Smith, Maurice Mell, Moctezuma, Joseph, Foley, Kevin Thomas
• Primary Examiner(s): Leubecker, John P.
• Application Number:
  US09/233,880
• Time in Patent Office: 699 Days
• Field of Search: 600/114, 604/264
• US Class Current: 600/114
• CPC Class Codes: A61B 17/1671 for the spine
• CPC Class Codes: A61B 17/3417 Details of tips or shafts, e.g. grooves, expandable, bendable; Multiple coaxial sliding cannulas, e.g. for dilating syringe needles A61M5/32; dilators A61M29/00
• CPC Class Codes: A61B 17/3421 Cannulas
• CPC Class Codes: A61B 2017/00261 Discectomy
• CPC Class Codes: A61B 2017/00296 mounted on an endoscope
• CPC Class Codes: A61B 2017/0046 with a releasable handle; with handle and operating part separable
• CPC Class Codes: A61B 2017/00469 for insertion of instruments, e.g. guide wire, optical fibre
• CPC Class Codes: A61B 2017/00477 Coupling A61B2017/0046 takes precedence
• CPC Class Codes: A61B 2017/3445 used as instrument channel for multiple instruments
• CPC Class Codes: A61B 2017/347 Locking means, e.g. for locking instrument in cannula
• CPC Class Codes: A61B 2090/062 penetration depth
• CPC Class Codes: A61B 2090/306 using optical fibres
• CPC Class Codes: A61B 2090/3614 using optical fibre
• CPC Class Codes: A61B 2090/373 using light, e.g. by using optical scanners
• CPC Class Codes: A61B 90/361 Image-producing devices, e.g. surgical cameras
• CPC Class Codes: A61B 90/50 Supports for surgical instruments, e.g. articulated arms
• CPC Class Codes: A61M 29/00 Dilators with or without means for introducing media, e.g. remedies instruments for performing visual medical inspections of cavities or tubes of the body A61B1/00

Abstract

A method for percutaneous surgery on the spine of a patient under direct visualization is performed through a single cannula having a predetermined length. The length is determined by measuring a distance from the lamina of a spinal vertebra to the skin of the patient, determining a first portion of the length to be less than the measured distance, and determining a second portion of the length to be about one fourth (1/4) the length of the first portion. The first portion is the length of the cannula to be introduced into the patient and the second portion extends external to the patient. This length is preferably 5.5 to 7.0 times greater than the transverse dimension of the cannula. Such dimensions for the cannula permits the longitudinal axis of a tool to be angled between 5 degrees and 8 degrees with respect to the longitudinal axis of the cannula.

Claims

1. A method for manufacturing an apparatus for use in percutaneous surgery on the spine of a patient, comprising the steps of:

(a) measuring a distance from the lamina of a spinal vertebra to the skin of the patient;

(b) determining a first portion of a length of a cannula to be less than the distance measured in step (a), the first portion for introduction into the patient;

(c) determining a second portion of the length of the cannula to be about one-fourth (1/4) of the length of the first portion, the second portion external to the patient; and

(d) providing the cannula having the length determined according to steps (b) and (c).

2. The method according to claim 1, wherein the cannula includes a circular cross-section along the length of the cannula.

3. The method according to claim 1, wherein the length of the second portion is less than about 30 millimeters.

4. The method according to claim 1, further comprising:

(e) providing a tool having an elongated shaft and a longitudinal axis extending therethrough, wherein the cannula provided in step (d) includes a working channel that permits the longitudinal axis of the tool to be angled between 5 degrees and 8 degrees with respect to a longitudinal axis of the cannula.

5. The method according to claim 1, wherein the cannula has a dimension transverse to its length, and further comprising:

(e) determining the length of the cannula to also be between 5.5 to 7.0 times greater than the transverse dimension.

6. A method for performing percutaneous surgery on the spine of a patient, comprising the steps of:

(a) measuring a distance from a spinal body to the skin of the patient;

(b) determining a first portion of a length of a cannula to be less than the distance measured in step (a), the first portion for introduction into the patient;

(c) determining a second portion of the length of the cannula to be about one-fourth (1/4) of the length of the first portion, the second portion external to the patient; and

(d) providing the cannula having the length determined according to steps (b) and (c).

7. The method according to claim 6, wherein the cannula includes a circular cross-section along the length of the cannula.

8. The method according to claim 6, wherein the length of the second portion is less than about 30 millimeters.

9. The method according to claim 6, further comprising:

(e) providing a tool having an elongated shaft and a longitudinal axis extending therethrough, wherein the cannula provided in step (d) includes a working channel permitting the longitudinal axis of the tool shaft to be angled between 5 degrees and 8 degrees with respect to a longitudinal axis of the cannula.

10. The method according to claim 6, wherein the cannula has a dimension transverse to its length, and further comprising determining the length of the cannula to also be between 5.5 to 7.0 times greater than the transverse dimension.

11. The method according to claim 6, wherein step (a) includes measuring the distance from the lamina to the skin.