Pen needle hub injection depth optimization
A needle hub ( 10 ) for a pen needle is provided with an enlarged surface for contact with the skin of a patient. The enlarged surface is provided with a surface having a dimension and shape to enable a needle or cannula to penetrate the skin to a desired depth and permit substantially the entire exposed length of the needle or cannula to penetrate the skin to the desired depth. The surface of the needle hub can be formed by an inner cone shaped member ( 26 ) forming a first contact surface with a surface area of about 1-5 mm 2 and an outer ring ( 28 ) at a peripheral edge forming a second contact surface with a combined surface area of about 15 to 50 mm 2 .
1. A needle hub, comprising:
a body comprising:
a proximal end configured for receiving and coupling to a pen needle delivery device; and
a distal end;
a post extending from the distal end of the body, wherein the post comprises:
a post side wall;
a top wall comprising an outer surface forming a contact surface for contacting a surface of a skin of a patient; and
an inner post extending from an inner surface of the top wall toward the proximal end of the body;
a plurality of ribs extending between the inner post and an inner surface of the post side wall for stabilizing the inner post; and
a cannula coupled to and extending from the post.
2. The needle hub of claim 1 , wherein the contact surface comprises:
an annular inner portion surrounding the cannula; and
an annular outer portion at a peripheral edge of the contact surface.
3. The needle hub of claim 2 , wherein the annular inner portion and the annular outer portion are aligned in a continuous curve.
4. The needle hub of claim 3 , wherein:
the annular outer portion comprises a first axial face;
the annular inner portion comprises a second axial face; and
the first axial face and the second axial face are aligned in the continuous curve.
5. The needle hub of claim 2 , wherein the contact surface comprises a continuous convex surface extending between the annular outer portion and the annular inner portion.
6. The needle hub of claim 5 , wherein the continuous convex surface is an annular recess.
7. The needle hub of claim 5 , wherein the continuous convex surface is concentric with the annular inner portion and the annular outer portion.
8. The needle hub of claim 2 , wherein the annular inner portion is spaced axially outward from the annular outer portion.
9. The needle hub of claim 1 , wherein the plurality of ribs extend from the inner surface of the top wall of the post an entire length of the post.
10. A pen needle assembly, comprising:
a pen body having a medication compartment and a distal end; and
a needle hub, comprising:
a body comprising:
a proximal end configured for receiving and coupling to the distal end of the pen body; and
a distal end;
a post extending from the distal end of the body, wherein the post comprises:
a post side wall;
a top wall comprising an outer surface forming a contact surface for contacting a surface of a skin of a patient; and
an inner post extending from an inner surface of the top wall toward the proximal end of the body;
a plurality of ribs extending between the inner post and an inner surface of the post side wall for stabilizing the inner post; and
a cannula coupled to and extending from the post.
11. The pen needle assembly of claim 10 , wherein the contact surface comprises:
an annular inner portion surrounding the cannula; and
an annular outer portion surrounding at a peripheral edge of the contact surface.
12. The pen needle assembly of claim 11 , wherein the annular outer portion and the annular inner portion are aligned in a continuous curve.
13. The pen needle assembly of claim 11 , wherein the contact surface comprises a continuous convex surface extending between the annular outer portion and the annular inner portion.
14. The pen needle assembly of claim 13 , wherein the continuous convex surface is an annular recess.
15. The pen needle assembly of claim 13 , wherein the continuous convex surface is concentric with the annular inner portion and the annular outer portion.
16. The pen needle assembly of claim 11 , wherein the annular inner portion is spaced axially outward from the annular outer portion.
17. The pen needle assembly of claim 10 , wherein the plurality of ribs extend from the inner surface of the top wall of the post an entire length of the post.
18. A needle hub, comprising:
a body comprising:
a proximal end configured for receiving and coupling to a pen needle delivery device; and
a distal end;
a post extending from the distal end of the body, wherein the post comprises:
a post side wall;
a top wall comprising an outer surface forming a contact surface for contacting a surface of a skin of a patient; and
an inner post extending from an inner surface of the top wall toward the proximal end of the body;
a plurality of ribs extending between the inner post and an inner surface of the post side wall for stabilizing the inner post; and
a cannula coupled to and extending from the post, wherein:
the contact surface comprises:
an annular inner portion surrounding the cannula;
an annular outer portion at a peripheral edge of the contact surface, wherein the annular inner portion and the annular outer portion are aligned in a continuous curve; and
a continuous convex surface extending between the annular outer portion and the annular inner portion, wherein the continuous convex surface is concentric with the annular inner portion and the annular outer portion.
19. The needle hub of claim 18 , wherein the continuous convex surface is an annular recess.
20. The needle hub of claim 18 , wherein the plurality of ribs extend from the inner surface of the top wall of the post an entire length of the post.
21. The needle hub of claim 18 , wherein the annular inner portion has a surface area in a range of 1-10 mm 2 .
22. The needle hub of claim 18 , wherein the annular outer portion has a surface area in a range of 10-40 mm 2 .
23. The needle hub of claim 18 , wherein the annular inner portion and the annular outer portion have a combined surface area in a range of 15-50 mm 2 .