Safety pen needle assembly

Abstract

A safety pen needle assembly includes a hub with a needle fixed to the hub, the needle having a distal end, formed for insertion into a patient, and a proximal end, a shield and a biasing member disposed between the hub and the shield configured to urge the shield distally. The shield is movable from a first position, when the needle is exposed, to a second position, when the needle is covered. The distal end of the needle may be initially exposed to permit visual confirmation of priming, while allowing the shield to cover a majority of the needle to minimize any needle-related anxiety.

1 - 6 . (canceled) 
     
     
         7 . A safety pen needle assembly comprising:
 a hub;   a needle fixed to the hub, the needle having a distal end formed for insertion into a patient and a proximal end;   a shield; and   a biasing means disposed between the hub and the shield configured to urge the shield distally, wherein:   a protrusion extends from at least one of the hub and the shield, and a channel is formed in at least the other of the hub and the shield, the channel formed to accommodate the protrusion;   the shield is movable from a first position to a second position, wherein:
 in the first position, the shield covers the distal end of the needle; 
 in the second position, the distal end of the needle is exposed; and 
 the channel guides the protrusion as the shield moves from the first position to the second position; and 
   the shield is initially in a locked state with the protrusion being spaced from the channel, the shield being manually movable out of the locked state to urge the protrusion into the channel thereby allowing the shield to move from the first position to the second position.   
     
     
         8 . The safety pen needle assembly of  claim 7 , wherein a locking aperture is formed in the at least the other of the hub and the shield and is spaced from the channel, the locking aperture formed to accommodate the protrusion in snap engagement in the locked state. 
     
     
         9 . The safety pen needle assembly of  claim 8 , wherein the locking aperture is circumferentially offset from the channel. 
     
     
         10 . The safety pen needle assembly of  claim 8 , wherein the locking aperture is longitudinally offset from the channel. 
     
     
         11 . The safety pen needle assembly of  claim 7 , wherein the shield is rotatable out of the locked state. 
     
     
         12 . The safety pen needle assembly of  claim 7 , wherein the shield is axially displaceable out of the locked state. 
     
     
         13 . The safety pen needle assembly of  claim 7 , wherein:
 the channel comprises a first part and a second part; and   a locking aperture is formed in the at least the other of the hub and the shield, the locking aperture being formed to receive the protrusion.   
     
     
         14 . The safety pen needle assembly of  claim 13 , wherein a ridge separates the locking aperture and the channel. 
     
     
         15 . The safety pen needle assembly of  claim 13 , wherein:
 in the first position, the protrusion is received in the locking aperture and engaging the locking aperture at a location more distal than a distal most portion of the first part of the channel; and   in the second position, the protrusion is seated in a first location and engages the distal most portion of the first part of the channel to retain the shield spaced from the distal end of the needle.   
     
     
         16 . The safety pen needle assembly of  claim 7 , further comprising a second channel formed in the at least the other of the hub and the shield, wherein:
 the channel is parallel to a longitudinal axis of the safety pen needle assembly;   the second channel is disposed transversely to and in communication with the channel; and   the shield is initially in a locked state with the protrusion positioned in the second channel, the shield being manually rotatable out of the locked state to urge the protrusion from the second channel into the channel thereby allowing the shield to move from the first position to the second position.   
     
     
         17 . A method, comprising:
 manually moving a shield of a pen needle assembly out of a locked state where the shield covers a distal end of a needle of the pen needle assembly; and   applying the pen needle assembly to skin of a patient such that the shield is depressed by the skin of the patient, wherein depression of the shield exposes the distal end of the needle.   
     
     
         18 . The method of  claim 17 , wherein moving the shield out of the locked state comprises rotating the shield out of the locked state. 
     
     
         19 . The method of  claim 17 , wherein moving the shield out of the locked state comprises axially displacing the shield out of the locked state. 
     
     
         20 . The method of  claim 17 , wherein:
 manually moving the shield out of the locked state comprises moving the shield to a first position where the shield covers the distal end of the needle; and   depression of the shield comprises the shield moving from the first position to a second position where the shield exposes the distal end of the needle.   
     
     
         21 . The method of  claim 20 , wherein the pen needle assembly comprises:
 a hub, wherein the needle is fixed to the hub;   a protrusion extending from at least one of the hub and the shield; and   a channel formed in at least the other of the hub and the shield, the channel formed to accommodate the protrusion, wherein:
 the protrusion is spaced from the channel when the shield is in the locked state; and 
 manually moving the shield out of the locked state further comprises moving the protrusion into the channel, wherein the channel guides the protrusion as the shield moves from the first position to the second position. 
   
     
     
         22 . The method of  claim 21 , wherein:
 manually moving the shield out of the locked state comprises moving the protrusion from a locking aperture formed in the at least the other of the hub and the shield into the channel; and   the locking aperture is separated from the channel by a ridge.   
     
     
         23 . A medical injector comprising:
 a needle; and   a slidable body disposed adjacent to the needle, the slidable body having depth marks defined thereon, wherein:
 during an injection of the needle into a patient, the slidable body is depressed by skin of the patient; and 
 the depth marks indicate an extent of depression of the slidable body during the injection thereby providing an indication of a depth of injection by the needle. 
   
     
     
         24 . The medical injector of  claim 23 , wherein the slidable body comprises:
 a slidable first member slidably attached and in contact with an outer surface of a portion of the medical injector at a portion offset from an axis of the needle, wherein the depth marks are defined on the slidable first member; and   a shield portion connected to a distal end of the slidable first member, wherein during the injection of the needle into the patient, the shield portion is depressed by the skin of the patient.   
     
     
         25 . The medical injector of  claim 23 , wherein the slidable body is configured as a shape, having a non-circular cross-section, that matches up to an outer surface of the medical injector and is slidably attached to only a part of the outer surface of the medical injector at a portion offset from an axis of the needle. 
     
     
         26 . The medical injector of  claim 23 , wherein:
 the slidable body is slidably attached to an outer surface of a hub from which the needle protrudes; and   the slidable body includes a small diameter cylinder offset from an axis of the needle, wherein:
 the cylinder extends from a distal surface of the hub; and 
 a shield portion is at a top of the cylinder.