Systems and methods for monitoring a range of motion of a joint are described. For example, in one embodiment, a first set of sensors may sense accelerations of a first body portion located on a first side of the joint and a second set of sensors may sense accelerations of the second body portion located on a second opposing side of the joint. The acceleration data may then be used to compute the relative motion of the first and second body portions to determine movement of the joint. This joint movement may then be used to determine one or more range of motion movement metrics which are output for viewing by a subject or medical practitioner.