An apparatus to support a users limb enhances the range of motion of the limb and permits the positioning of a counterforce to be adjusted, which corresponds to the weight of the limb. The apparatus includes a vertical member having a first end coupled to a structure and a second end having a spring mechanism, a horizontal arm assembly rotatably mounted to the spring mechanism by a joint assembly, the horizontal arm assembly having a first arm member coupled to a first side of the joint assembly and a second arm member coupled to a second side of the joint assembly, a limb support assembly coupled to the first arm member of the horizontal arm assembly and having a cuff to enclose a portion of the limb, and a counterweight member slidably mounted to the second arm member.
