Swollen wrists are often a result of traumatic injuries like sprains, bone fractures, or even bruising. You may also experience swelling due to overuse or arthritis, which results from inflammation of the joints.
Sometimes, wrist swelling can occur even without any underlying injury. Stress caused by repetitive activities like typing or knitting can also contribute to wrist pain and swelling.
Fluid accumulation in your body's tissues is what causes swelling or edema in general. The small blood vessels inside the body start leaking fluid whenever a body part becomes injured, inflamed, or damaged. White blood cells appear to help repair the damage, starting to cause more fluid leakage and swelling.