The Aircast Cryocuff - Use in Physiotherapy
by Jonathan Blood Smyth

The Aircast Cryocuff is a useful, portable and flexible device for the management of knee injury, pain and swelling. Used commonly by physiotherapists, it can be an important tool in knee injury and post-operative management of knee operations, where the application of cold therapy is difficult with traditional methods.

Physiotherapists commonly assess and treat knee injuries and post-operative knee conditions, managing them promptly for speedy recovery and return to normal function. Recreational activities and sport involve many knee injuries such as ligamentous injuries to the medial, lateral and anterior cruciate ligaments, meniscal injuries to the knee cartilages, dislocation of the kneecap and injury to the knee capsule and knee joint replacement.

The knee is a large, synovial hinge joint which is vulnerable to mechanical injury and when injured it reacts with an inflammatory process. This increases the blood supply and metabolic rate of the knee and the synovial lining starts to secrete synovial fluid, a process which forms a knee effusion. This is "water on the knee", a swollen knee with synovial fluid making the knee painful and tight, which can interfere with normal functioning of the knee muscles and cause slow recovery of joint function.

Physiotherapy methods of cooling tissues usually have some disadvantages:

Both cold and compression need to be provided and this is hard to achieve Most ice based methods do not cool the knee effectively The skin can however develop an ice burn from overcooling at ice temperatures Compression is difficult to provide along with the cooling Patients have difficulties keeping the cooling going for any length of time Cooling cannot easily be done whilst mobilizing.

Physiotherapy treatment priorities have always tended towards cooling the area to reduce the swelling, but prevention of the effusion by early compression may be more important. However, physios do need to provide cooling along with the compression.

The Aircast Cryocuff

The Aircast Cryocuff is a portable, convenient device for providing both compression and cooling for the management of acute or post-operative knee (or other joint) conditions. It consists of three parts:

The Water Bucket. This water/ice reservoir is a plastic cylinder with a lid and guidance markings inside the bucket for the proportions of ice and water to fill for optimal use of the device. The lid is screwed on securely to avoid leakage and the contents can be remixed by simply turning the whole assembly upside down a few times. The Hose. The hose has an easy to use clip system to facilitate connection and disconnection of the insulated hose. The Cuff. The material cuff fits snugly around the knee for good anatomical contact, comes in three sizes and Velcro fastenings for a secure fit.

Physiotherapy Application of the Cryocuff

The size of the cuff needed for the patient is measured by the physio 6 inches above the kneecap and then the cuff is fitted snugly to the knee and firmly attached with the Velcro straps. It is important to start with the cuff deflated or the benefits of compression of the Cryocuff will not be forthcoming.

The bucket should contain the correct mixture of cold water and cubed ice with the top screwed on well to avoid leaks. The physio attaches the hose to the clip on the cuff and lifts the bucket above knee level to allow the cold water to fill the cuff by gravity. The height of the bucket and how long it is held up will determine how tight the cuff is inflated with water.

The cuff is left on for an hour or so until it warms, with the patient able to move about and do exercises. The hose is reconnected and the bucket placed below the knee level to allow the water to flow back into the bucket. Then the bucket is upended a few times to remix the water with the ice and the application procedure repeated. This allows continuous compression and cryotherapy over an extended period, with the ice/water mix remaining cold for six to eight hours before replacement of ice is needed.