Joint proprioception is the sense of joint position. Proprioception tells us if the joint is flexed forward or raised overhead. Joint position sense tells the person where the joint is in relation to the body and the other joints.

Like many things, proprioception does decline with age but usually in small amounts. Most people aren't really aware of the change. Many different things can cause loss of motion. Arthritis is the number one problem in aging adults. Inactivity can lead to decreased motion and even a frozen shoulder.

Sometimes people with heart disease become breathless when their arms are raised overhead so they stop using this motion. Forgetting how to do simple tasks such as raising the arms overhead can be a part of Alzheimer's. This isn't an early sign, though. It usually happens later on as the disease progresses. If your mother doesn't have any other signs of Alzheimer's, this loss of motion is likely caused by something else.

Make an appointment with her doctor for an evaluation. Early identification and treatment of some problems can help prevent long-term complications.