Morning stiffness of the ankle joint may be described as rigidity in the ankle joint after waking up in the morning or after a resting period that makes it difficult to perform activities like walking, running, standing etc. It may be severe but is usually brief for less than 30 minutes.
The most common cause of morning stiffness of the ankle joint is rheumatoid arthritis or osteo arthritis. Both these disorders causes inflammation and stiffness but RA is more specifically related to morning stiffness.
Although it is hard to describe morning stiffness but patient generally complains of an ache or discomfort in the ankle joint combined with difficulty moving it for activities like walking, running, standing etc.