Donjoy Armor Professional Knee Brace with FourcePoint Hinge
If you're returning to sport after a serious knee injury, the Donjoy Armor Professional Knee Brace with FourcePoint Hinge is the gold standard in knee protection. Designed with spring-loaded Fourcepoint hinges, it greatly reduces pressure on ACL to prevent reinjury, while also applying resistance to maintain your natural gait and peak athletic performance. This dynamic support makes it a popular choice for high-impact sports like skiiing and the level of resistance can be adjusted to adapt as you're able to put more weight on your knee.
What's Included?
The Donjoy Armor with Fourcepoint is supplied with everything needed to start receiving the best ACL support right away. It includes:
- 1 x Donjoy Armor Knee Brace with Fourcepoint
- 2 x Anti-Migration Condyle Pads
- 1 x Mesh Carry Bag
- 1 x Warranty Card
Which Size Do I Need?
The Donjoy Armor with Fourcepoint Knee Brace is available in seven sizes and is suitable for men and women. To determine which size is right for you, you must measure the circumference of your thigh, knee and calf (as shown), and then refer to the tables below.
The thigh measurement is taken around the thigh 15cm (6") above the centre of the kneecap. The knee cap measurement is taken directly around the centre of the knee cap. The calf measurement is taken around the calf 15cm (6") below the centre of the knee cap.
Size | Thigh Circ. (1) | Knee Circ. (2) |
Extra Small | 33 - 39cm | 30 - 33cm |
Small | 39 - 47cm | 33 - 35cm |
Medium | 47 - 53cm | 35 - 38cm |
Large | 53 - 60cm | 38 - 43cm |
Extra Large | 60 - 67cm | 43 - 48cm |
XX-Large | 67 - 75cm | 48 - 53cm |
XXX-Large | 75 - 83cm | 53 - 58cm |
Size | Calf Circ. (3) |
Extra Small | 25 - 30cm |
Small | 30 - 35cm |
Medium | 35 - 40cm |
Large | 40 - 45cm |
Extra Large | 45 - 50cm |
XX-Large | 50 - 55cm |
XXX-Large | 55 - 60cm |
Sizing Tips
- If your thigh, knee and calf measurements don't match up, we recommend choosing your size based on your knee measurement
- If you do not have a flexible tape measure, use a piece of string to measure your knee and then measure the string with a ruler
- Before choosing your size, please take into consideration any joint swelling or atrophy that may have occurred
What Conditions is the Donjoy Armor Designed For?
The Donjoy Armor is the best brace to use for active people suffering from ACL instability or injury. This ACL knee support is particularly suited to treatment and protection of:
- Moderate to severe ACL instability
- Recovery from ACL reconstruction and surgery
- MCL or LCL instability
- Meniscus injury
- Hyperextension prevention
Key Features
- The ultimate knee support for supporting and protecting the ACL
- Provides support with an enhanced "Four Points of Leverage" system
- Resistance threshold is adjustable based on your stage of recovery
- Ideal for providing support during recovery from knee injury
- Gradual soft stop the extension for comfortable movement
- Helps prevent hyperextension of the knee
- Suitable for both men and women
- Short calf design to fit into ski boots and skates
- Made with a mouldable, medial swooping frame for custom fit
- Includes a 1 year warranty on frame and hinge
- Includes a 6 month warranty on soft goods
How Does the Donjoy Armor with Fourcepoint Support the ACL?
The strongest and most supportive ACL brace around, the Donjoy Armor with Fourcepoint is a hinged knee brace using the Donjoy Fourcepoint hinge technology. The spring-loaded Fourcepoint hinges keep the hamstring in constant tension, and takes pressure off the ACL using a "Four Points of Leverage" system. As the hamstring is attached to the tibia (or shin bone), the hamstring tension pulls the tibia back keeping it stable and almost entirely eliminating the chance of an ACL injury.
How Do I Fit my Donjoy Armor Support?
For fitting instructions, please view the easy-to-follow video below!
Which Sports Is This Knee Support Designed For?
The Donjoy Fourcepoint Knee Brace is designed to provide maximum protection to the knee for high impact and contact sports. Among others, this knee brace is suitable for:
- Skiing and snowboarding
- Motocross
- Football
- Hockey
- Volleyball
- Baseball and softball
- Extreme and contact sports
- Watersports (including salt water)
How Does the Fourcepoint Hinge Improve ACL Support?
While the Donjoy Armor is available without Fourcepoint technology, it's the Fourcepoint hinge that really puts this brace at the top of the class in terms of ACL support. The brace works by limiting the time your knee is in an "at risk" position, increasing the posterior load applied by the brace on the tibia when you reach a certain level of knee flexion. This dampens knee extension and reduces shear forces on the knee, all while improving your natural gait by applying increasing resistance until you reach a firm point during your natural movement.
How Durable Is the Donjoy Armor?
Constructed from light aircraft grade aluminium, the Donjoy Armour with Fourcepoint Knee Brace is exceptionally strong and lightweight and enables you to continue with any sporting activity. As this is the standard short calf version, the knee injury brace doesn't interfere with either a ski or motocross boot and remains clear from the top of your boot. This makes the support more versatile, allowing it to be used without restriction across a number of sports.
What Is the Four Points of Leverage System?
As is mentioned above, the Donjoy Armor uses a "Four Points of Leverage System" to increase the posterior load on your tibia, thereby reducing the load on your ACL. These leverage points are labelled in the diagram below.
Can the Fourcepoint Hinge Be Adjusted?
The Fourcepoint Hinge allows you to set your flexion levels based on your stage of recovery. This adjustment changes the angle where the Fourcepoint's tension stops, allowing you to choose between 25°, 35° (default setting), 45°, 55° or 65°. This allows you to choose the perfect level of movement for you, and lets you add progressively more range of motion as you recover. The level you choose should be based on your doctor's advice and your own personal comfort.
Will the Donjoy Armor Fit Into Ski Boots?
This is the short calf version of the Donjoy Armor, meaning the calf portion is shortened to allow it to fit into ski boots, snowboard boots, skates, and other specialist footwear that requires space on the calf. Designed primarily for skiing and high-impact sports, the Donjoy Armor is definitely the best Donjoy brace for skiing.
Will This Knee Brace Stay Put?
To ensure it's always providing support to your ACL, this knee brace is designed to stay put even during intense activity. It does this with the anti-migration supra condyle pads, which hold the knee in place at the centre of the brace to ensure it doesn't slip. The images below show the inside of the brace with, and then without, the condyle pads fitted.
Is This Knee Brace Heavy?
While incredibly strong, this knee brace remains light enough to avoid hindering athletic performance or weighing you down. Weighing in at just 612g (1.35lbs) the Donjoy Fourcepoint Knee Brace made with 6061 T6 aircraft aluminium, meaning it provides maximum strength with minimal weight.
Why Does the Donjoy Armor Offer Adjustable Tension?
The Donjoy Armor is designed to react during leg extension and offer an increasing resistance in the last 35° of extension at factory setting. It does this in order to reduce extension shock and increase posterior tibial loads, thereby reducing the strain placed on your ACL.
Are Comfort Liners Available?
While the Donjoy Armor is anatomically designed for maximum comfort, intense activity may cause it to catch the skin at certain areas. To avoid this, a Donjoy Armor Black Lycra Undergarment is available to protect the skin and make wearing your brace more comfortable. This liner can be added to your order using the drop-down menu near the top of the page.
How Can I Cushion the Brace for Contact Sports?
Since the Donjoy Armor with Fourcepoint is made with aircraft-grade aluminium, we recommend covering it to avoid injuries to your opponents. For the purpose we would recommend the Donjoy Armor Sports Cover, which is a padded cover designed to cushion your brace without affecting use. You can add it to your order using the drop-down menu near the top of the page.
Can I Wear the Donjoy Armor Over My Clothes?
Donjoy do not advise you wear your knee brace over your clothes, as the support provided by the hinges on either side of the knee joint will be compromised. The Donjoy Armor is designed to always be worn underneath clothes to achieve the incredible level of support the brace provides.
How Long After Surgery Can I Wear the Donjoy Armor Brace?
Unfortunately, everyone's recovery and condition is different, so there's no concrete time frame as to when you should start wearing the Donjoy Armor Brace. We would recommend that you consult your doctor, and come up with a plan that includes the introduction of your Donjoy Armor Knee Brace at a certain point in your recovery.
Is the Donjoy Armor with Fourcepoint Suitable for Salt Water Sports?
Yes, the Donjoy Armor is an excellent option for ACL support during water sports such as wakeboarding and water skiing. If you intend to use your Donjoy Armor in salt water, we would recommend rinsing it with clean water after each use to maximise longevity.
Is this Brace Suitable for PCL Injuries?
No, this brace is NOT suitable for PCL lesions and injuries, as this brace is only designed for ACL injuries. The Fourcepoint hinge provides resistance that will increase force on the PCL, making it entirely unsuitable for recovery from PCL injuries. If you have a PCL injury or have a combination of knee injuries or problems and require a combined instability knee brace (CI), please see the Donjoy Armor Professional Knee Brace without Fourcepoint.