1. Field of the Invention
The present invention relates generally to an orthopedic appliance and, more particularly, to a knee brace.
2. Description of the Prior Art
The knee is the largest joint of the body formed generally by the hinge-joint of the thigh-bone (femur) above, the shinbone (tibia) below and the kneecap (patella) in front. That joint, which is capable of more movement than either those of the fingers or the elbows, is subject to many injuries due to its complex structure and the fact that it also has to sustain the greatest stresses since it supports the entire weight of the body and of the upper portion of the leg. Such injuries include a twisting or overextension of the knee joint. All knee injuries require a slow and gradual return to normal activity to avoid a recurrence and permanent crippling. In some instances, the knee must be immobilized to permit healing; in other cases, adequate support must be provided to the knee during the normal activity of the user.
The movements which take place at the knee joint are flexion and extension, and, in certain positions of the joint, medial and lateral rotation. The movements of flexion and extension at this joint differ from those in a typical hinge joint, such as the elbow, in that the axis around which motion takes place is not a fixed one, but shifts anteriorly during extention and posteriorly during flexion; and the commencement of flexion and the end of extension are accompanied by rotatory movements associated with the fixation of the limb in a position of great stability.
The typical prior art knee brace which permits flexion and extension of the knee includes a structure or framework which encircles the knee and which has a hinged joint. Since that brace forces the knee to move about that hinged joint, the knee is not allowed its normal movement of flexion because the axis around which the movement of the brace takes place is fixed. Additionally, the prior art braces do not allow rotation or the locking home mechanism of the knee joint.
Further, it is common for conventional knee appliances to be bulky and uncomfortable to wear. A number of the prior art devices have to be form-fitted to the user's knee. They also do not operate effectively in applying sufficient force on the user's knee due to their lack of three-point fixation.