High blood glucose over a long period of time can increase the stiffness of tissue around your finger joints. This can eventually cause stiff hands and prevent you from straightening your fingers. This stiffness may make it difficult to write or to pick up small items and do other fine movements.
An easy test for this condition is called the "prayer sign," in which you hold your hands together, one palm facing the other palm, to see whether your fingers can lie flat against each other. If a space exists between your right and left hands when you try to push your hands together, this is a "positive" prayer sign. High glucose may be causing this condition. Arthritis can also cause a positive prayer sign.In the near future, new medications may become available that will reduce this stiffness. In the meantime, you should try to keep your blood glucose as close to your goal range as possible.