The present invention provides an orthosis for stretching tissue around a joint of a patient between first and second relatively pivotable body portions. The orthosis includes a first member affixable to the first body portion and including a first extension member defining an arcuate channel therein. A second member affixable to the second body portion is also included and has a second extension member having an arcuate shape extending there from. The second extension member is operatively connected to the first extension member and travels through and within the arcuate channel, along the arcuate path, when the second arm member is moved from a first position to a second position relative to the first member.