The vast majority of upper limb injuries in swimming are to the shoulder. More than 90%. Then the elbow, then the wrist, and then the finger. Usually wrist injuries are due to overuse or poor technique. Finger injuries occur when hands get smacked against the edge of the pool or hyper-extended in that last desperate lunge to the wall. The trick comes in how to manage these, especially in someone who needs to swim regularly.
It all starts, as it always should and especially with overuse injuries, with a detailed history. If a swimmer is compensating for shoulder pain, extra strain can be felt through the wrist. If a swimmer has had a different injury like a fractured distal radius, then her return to the pool can be compromised not necessarily just by a loss of motion, but more likely due to a loss of forearm strength. A lack of strength can then be exacerbated when swimming equipment like hand paddles are utilised, and wrist stability is compromised. Having said that, if you are sensible, the training aids like fins or paddles can actually help offload an injury. There is almost always a way
Consider different strokes. It is obvious, or at least should be once you stop and think about it, that breaststroke utilises different muscles to free style. Just have a look at the body shapes of Olympic swimmers. The demands the strokes place on the wrist will change as shoulder position changes. Feathering of the hand through the water will also alter. Use this to your advantage. If one style is inflammatory, can you integrate another so that swimming fitness is maintained throughout recovery? There will be a way.