A number of design features are built into a surgical needle to meet different needs.
Parameters:
(1) diameter of needle
(2) end attachment for suture
(3) cross-sectional shape of distal body (to improve use with instruments)
(4) cross-sectional shape of proximal body
(5) point or tip
The greater the diameter of the needle, the greater its strength, but also the size of the hole. A large, irregular hole may seep fluid or result in a loose closure.
End attachment for suture:
(1) eyelet (traumatic)
(2) eyeless (embedded into hole at the end of the needle, atraumatic)
The distal body tends to have a flat surface to minimize rotation when held in a needle clamp.
Cross-Sectional Shape of Proximal Body |
Term |
triangular, with sharp apex along inner surface of suture |
cutting |
triangular, with sharp apex along outer surface of suture |
reverse cutting |
round |
round bodied |
rhomboid |
spatula |
A cutting needle has a sharp edge to help cut through tough, resistant tissues (it can also be used to cut through a suture held taut). A reverse cutting can be useful in delicate areas when edges are close together; a regular cutting needle might cut right into the defect being closed, weakening the closure.
Point or tip:
(1) cutting point
(2) tapered point
(3) round point
(4) blunt
(5) specialty design (proprietary to a company)
A sharp point helps a needle penetrate tissue. A blunt tip reduces the risk of sharps injury.