Basic Sciences - Cortical vs Cancellous Screws

Description

In this lesson on Basic Sciences, the focus is on the comparison between cortical and cancellous screws, essential tools in surgical procedures. The presentation starts by explaining the fundamental function of screws as mechanical devices that transform rotational force into linear movement. It outlines the different types of screws, highlighting the distinction between cancellous and cortical varieties, as well as the concepts of locking and non-locking screws.



Self-tapping screws, designed with a fluted tip to remove bone debris, are discussed, with a note on their comparatively lower bone holding capacity. Cannulated screws, which assist in precise placement near joint surfaces, are also introduced.



The differences between cancellous and cortical screws are detailed, focusing on three main characteristics: pitch, the core diameter to outer diameter ratio, and the design of the tip. Cancellous screws are identified as having a larger pitch with widely spaced, deeply cut threads, whereas cortical screws possess a smaller pitch and closely spaced threads. Additionally, cortical screws feature a higher core diameter to outer diameter ratio and are characterized by their blunt ends.

Specialties