An adjustable tension knee brace for unloading weight from a knee joint afflicted with osteoarthritis, thus reducing pain and improving mobility, comprising: an upper and lower rigid posterior portion, anterior straps, and a tension adjustable geared hinge assembly. Four embodiments are disclosed of hinge assemblies useable with the knee brace, or other types of braces. The hinge assemblies comprise: two subunits housing intermeshed gears, and at least one elastic band extending between the hinge subunits over a cam surface above the gears. In three embodiments, U-shaped connectors secure the subunits and gears together, and the subunits may comprise a user mechanism that adjusts the elastic band's tension and thus the amount of weight unloaded, then releases it. Another embodiment comprises a core bracket to protect the band(s) and a mechanism to compress the elastic band at various points to increase the amount of tension, and with a quick release mechanism.
