Reverse Engineering A Guidewire Assembly

At Modern Grinding we often get inquiries to help medical device designers reverse engineer a guidewire assembly so that we can manufacture something similar for their device or for their distribution business. It seems like a simple enough request. Modern Grinding is in the guidewire assembly business, how difficult can it be to slap a coil, safety ribbon and core wire together? It actually isn’t too difficult (for us), but we need to know the exact design. Here are some of the hiccups that occur when reverse engineering a guidewire assembly.

Guidewire Assembly Formed Core Wires
Guidewire Assembly Formed Core Wires

Guidewire Use Case

The most important part of a guidewire is how it is used. At Modern Grinding, we are contract manufacturers, we aren’t doctors. When someone comes to us and asks us to “copy” a guidewire, we don’t always know that exact guidewires use case. If we were to get something wrong, that can affect how the guidewire performs in surgery. Often foreign distributors will try to gloss over that fact, and say just give us something close (to another product in the market). At Modern Grinding, we take a deep concern for how our guidewires perform and we won’t accept “close”.

Guidewire Concerns

There are many small pieces of the puzzle which affect how a guidewire performs. How is the core wire connected to the coil? Is it welded or glued or fused? What tensile strength is the core wire? This can affect it’s flexibility and propensity to return to its original shape. Was the core wire heat treated? This again can affect the shape of the core wire and how it returns to its original form. What dimensions does the core wire have and what dimensions do the coils have? How much of the coil is coated? What is the tip coated with? How is the handle connected? Are all forms of PTFE the same? Are all hydrophilic  and hydrophobic coatings the same? While these all seem like little details, when you combine them all, you can lead to vastly different guidewires that appear the same.

New Guidewire Designs from Doctors

When doctors reach out for help, I feel bad if we can’t help. Often doctors come to us with a problem that they recognize with a pre-existing device. They are in the perfect position to come up with a new guidewire design that could better serve patients and help other doctors as well. The problem is that doctors don’t realize how difficult it can be to reverse engineer a product and then make a fairly similar guidewire assembly. We can do it, but we need to be able to nail down all of the key characteristics (see concerns section above) before we can start to make alterations on the wire. It takes a lot of engineering time to reverse engineer a complex product which is used in surgical applications.

This post wasn’t meant to scare anyone, just to let you know what goes into reverse engineering a guidewire assembly. We can do it, but it typically takes a couple days in engineering time, we aren’t able to just “copy” an existing wire without going through a very refined process.