Devices, systems, and methods for maintain a preselected tension between a first portion and a second portion of an orthotic brace include a controlled tension unit comprising a housing coupled to a first portion of the orthotic brace, the housing having a cavity formed therein, one or more constant-force spring mounted at or near a first end of the cavity, and a connector cable having a first end connected to an end of the one or more constant-force spring and a second end extending out of the housing through a second end of the cavity. The second end of the connector cable is configured to connect with a coupling element coupled to a second portion of the orthotic brace. In this arrangement, the controlled tension unit is configured to maintain a preselected tension between the first portion and the second portion of the orthotic brace.
