The invention provides a device for protecting ligaments in a knee joint of a user. The device includes a knee brace positionable about a knee joint of a user and a boot wearable on a foot of a user. Additionally, the device includes a flexible tether member including a first coupling element coupled to the knee brace and a second coupling element coupled to the boot. The boot and knee brace are attachable and detachable via the first and second coupling elements. The flexible tether member is adjustable in length to dispose the flexible tether member in tension at least in a portion of a maximum foot range of rotation, where the maximum foot range of rotation of the user's foot relative to the knee joint causes hyperextension of a knee ligament.