The invention relates to an orthosis (100) and method for the treatment of wrist and elbow illnesses. The orthosis (100) includes a first cuff (101) adapted to be secured to a hand of a user. A second cuff (102) is adapted to be secured to an upper arm portion above an elbow joint of the user. The first cuff (101) and the second cuff (102) include a first attachment point (103) and a second attachment point (104), respectively. The orthosis (100) also includes a resilient member (105) having a first end (106) and a second end (107) opposing the first end (106). The first end (106) of the resilient member (105) is attached to the first attachment point (104) of the first cuff (101). The second end (107) of the resilient member (105) is attached to the second attachment point (104) of the second cuff (102). The first attachment point (103) and the second attachment point (104) are positioned such that a wrist extension force and a forearm extension force are opposed by a counteracting force produced by the resilient member (105). The counteracting force opposes the rotation of the forearm relative to the upper arm about the elbow joint and maintains the wrist in a substantially flexion position.