Surgical needle assembly

• US 5,336,191 A
• Filed: 08/13/1992
• Issued: 08/09/1994
• Est. Priority Date: 08/13/1992
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: DLM Incorporated (Medtronic Plc)
• Inventors: Greenhoe, William J., Davis, Richard E.
• Primary Examiner(s): Hirsch, Paul J.
• Application Number:
  US07/930,098
• Time in Patent Office: 726 Days
• Field of Search: 604/164, 604/165, 604/274, 128/754
• US Class Current: 604/165.01
• CPC Class Codes: A61B 10/0283 with vacuum aspiration, e.g. caused by retractable plunger or by connected syringe A61B10/025, A61B10/0266 take precedence
• CPC Class Codes: A61B 17/3401 Puncturing needles for the peridural or subarachnoid space or the plexus, e.g. for anaesthesia local anaesthesia A61M19/00
• CPC Class Codes: A61B 2017/347 Locking means, e.g. for locking instrument in cannula

Abstract

A surgical needle with a stylet selectively received within the lumen of a cannula is shown where establishing and maintaining a desired angular orientation between the stylet and cannula is achieved. The orientation may be determined in one of several ways. Preferably, a projection is mounted to the cannula hub which is selectively received in a recess of the stylet cap when the stylet and cannula are in the desired orientation. Alternatively, a pair of flexible arms may be mounted to the stylet cap wherein detents on the distal ends of the flexible arms are selectively received within complementary depressions on the cannula hub when the stylet and cannula are in the desired orientation. Also, a longitudinal rib on the stylet cap and a projection on the cannula hub can be visually inspected or can be felt by the user to determine the orientation. Finally, a projection from the cannula hub may be selectively received within a slot on the stylet cap to ensure proper alignment of the stylet and cannula.

Claims

1. In a surgical needle including a cannula member and a stylet member, the cannula member comprising a cannula handle and a cannula having a proximal end affixed to the cannula handle and a distal end opposite the cannula handle, the stylet member comprising a stylet handle and a stylet having a proximal end affixed to the stylet handle and a distal end opposite the stylet handle, the stylet being removably receivable within the lumen of the cannula, the axial dimensions of the stylet and the cannula being so related that when the stylet is fully received within the cannula with the handles adjacent to each other the respective distal ends are coterminous, the distal ends being respectively contoured to form a predetermined needle tip configuration when the stylet is fully received in the lumen of the cannula in predetermined angular relation therewith, the improvement wherein:

one of the handles includes a receivable projection formed on an exterior surface; and

the other of the handles comprises a hollow body having a locking recess formed on an interior surface thereof, said other handle receiving at least a portion of said one handle within the hollow body when the stylet is fully received in the cannula, the receivable projection and locking recess being so formed and situated that the receivable projection is snap-locked in the locking recess when the cannula and stylet are in said predetermined angular relation.

2. A surgical needle according to claim 1 further comprising at least one guide projection mounted on one of the handles and a longitudinal rib mounted on the other of said handles wherein the at least one guide projection and longitudinal rib are aligned when the stylet and the cannula are in said predetermined angular relation.

3. A surgical needle according to claim 2 further comprising a slot in one of said handles whereby said at least one projection is received in said slot when the stylet and the cannula are in said predetermined angular relation.

4. A surgical needle according to claim 1 further comprising a reservoir in said cannula handle which is in fluid communication with said lumen of the cannula.

5. A surgical needle according to claim 4 further comprising a syringe mounting attached to one end of the cannula handle and an aperture extending through the mounting wherein said aperture is in fluid communication with said reservoir of the cannula handle.

6. A surgical needle according to claim 1 wherein said contoured distal end of the cannula is angled at an acute angle with respect to the longitudinal axis of the cannula and said contoured distal end of said stylet is angled such that it lies on the same plane as the contoured end of the cannula when the styler is fully received in the lumen of the cannula in said predetermined angular relation therewith.

7. A surgical needle according to claim 1 wherein said other handle is deformable to selectively disengage the receivable projection from the recess.

8. A surgical needle according to claim 1 wherein the one of the handles is the stylet handle and the other of the handles is the cannula handle.

9. A surgical needle according to claim 1 wherein the locking recess comprises a depression formed in the interior surface said other handle.

10. A surgical needle according to claim 1 further comprising a second receivable projection provided on one of the handles and a sliding recess mounted on the other of the handles, the sliding recess being complementary in shape to the second receivable projection and the second receivable projection being slidably received in the sliding recess when the stylet and the cannula are in said predetermined angular relation.

11. A surgical needle according to claim 10 wherein the receivable projection second depends from the stylet handle and the recess sliding is formed in the cannula handle.

12. A surgical needle according to claim 11 wherein the stylet and cannula handles are adapted such that the stylet handle must be deformed by squeezing its hollow body in order to selectively engage or disengage the receivable projection from the locking recess, thereby mounting the stylet and cannula in the predetermined angular relation or removing the stylet from the predetermined angular relation with the cannula.