Compression garments are used for people you have lymphedema and circulatory problems. Compression garments have a gradient pressure which means they are tighter closer to your hand or foot and gradually have less and less pressure. The gradient pressure encourages the accumulated fluid towards your torso and back to your heart where it returns to the blood.
There are two types of compression garments, circular knit and flat knit. Circular knit is knitted in a spiral and does not have a seam. They have less containment that flat knit. This means that even though they have the same pressure they are a little stretcher and have more give. Because of this, circular knit is better for circulatory insufficiencies like chronic venous insufficiency. Flat knit is made using a straight knit and then the edges are sewn to make the garment. This style of knitting makes the garment more durable and makes it have more containment. Because of this, flat knit garments are better suited for more severe lymphedema. Flat knit garments are also a lot more customizable which is often needed for lymphedema.
The compression in compression garments are measured using millimetres of mercury (mmHg) or in classes. The measurements are different between flat knit and circular knit garments. For circular knit a class I compression is usually between 20 to 30 mmHg, class II is 30 to 40 mmHg, and class III is 40 to 50 mmHg. For flat knit a class I is 18-21 mmHg, class II is 23-32, class III is 34-46 mmHg, and class IV is 55 mmHg. You will notice that for the same class of compression the flat knit has a lower mmHg. This is because flat knit has less stretch and therefore can contain the swelling better than circular knit does with less compression.
Measuring for these garments should be left to those who are certified garment fitters. There are many factors that have to be known to measure a garment well. Each garment company measures their garments a little differently and there are often many adaptations and features to choose from. Fitting a garment properly is not just about measuring, it involves knowing the patient and their condition well enough to understand what they need. Working with a lymphedema therapist that also knows how to fit garments ensures that you are getting the best care and the compression garment that best works for you.
Sarah Driediger is a certified garment fitter for Medi, Juzo, and Jobst compression garments. They boast a very large variety of garments with lots of customizable components.