Ice pack or cryocompression:
what the studies show

You have an ice pack in the freezer, and you are being offered a device to rent. The question is whether it is really worth the difference.

Two recent clinical trials compared exactly that, in patients after surgery, with the same rehabilitation in both groups.

What the trials measured

After shoulder surgery, 200 patients across 5 Canadian hospitals, dynamic cryocompression on one side, standard cryotherapy on the other¹. Patients on cryocompression used about half as many opioids¹, and their physical function at two weeks was better¹.

After a knee replacement, 40 patients in a rehabilitation centre, the Game Ready® against ice packs². At three weeks, on a six minute walk test, the patients on cryocompression covered about 100 metres more².

One thing these trials do not say: cryocompression does not remove pain. In the shoulder trial, the pain patients felt was comparable in both groups¹. What changes is how much medication it takes to get through, and how fast you walk again.

Why an ice pack plateaus

An ice pack does the job for ten minutes. After that it warms up and cools nothing. It starts too cold, with a risk of a cold burn on skin that is still numb. It fits a joint badly. And above all, all it does is cool.

A cryocompression device holds a stable cold, around 4 degrees, for the whole session. The benefit on pain and on swelling is most marked in that temperature range.

What compression adds

This is the half an ice pack does not do. Swelling is fluid that has collected in the tissues. Normally your muscle contractions are what push it back up, like a pump. After an operation you barely move: the pump runs in slow motion and the fluid sits there.

Dynamic compression takes over. It inflates and deflates in cycles, which pushes the fluid upwards instead of simply pressing on it. That is why it is intermittent rather than continuous, constant pressure hindering the circulation instead of helping it.

Cold limits the inflammation, compression clears the swelling that is already there. That combination is what separates it from an ice pack.

How it is used

Sessions of 20 to 30 minutes. Three to four a day in the first week, the one where swelling and pain are at their highest. After that, before a physiotherapy session, to mobilise a joint that hurts less, or after one, to limit the swelling the exercises cause. And a session before bed, which many patients name as the one that changes their nights the most.

The limits

Cryocompression does not replace rehabilitation, which remains what gives you back your mobility and your strength. It does not replace the pain medication you have been prescribed either. And it does not suit every situation: certain circulation disorders and certain problems with skin sensation are contraindications, which your surgeon will confirm for your case. Ask them before renting rather than after. It is a two minute conversation at your discharge appointment.