Sprained ankles are very common injuries in most sports, particularly basketball, netball, football and soccer. They occur when the ankle rolls in (inversion sprain) or out (eversion sprain) to an extent that damages the ligaments which prevent these movements.
The severity of an ankle sprain can range from a minor injury which should recover fully within two weeks, to a severe sprain which may take several months to recover and sometimes requires surgery.
Ankle sprains don't routinely require an X-ray or other imaging, however your physiotherapist will be able to refer for scans should they feel they are required.
For at least 3-5 days after the injury the ankle will respond well to relative rest, applying ice for 20 minutes every few hours, applying compression, and elevating above the level of the heart (RICE) to reduce swelling. Physios can also apply techniques such as joint mobilisations, therapeutic ultrasound and electrotherapy to help to manage pain and swelling in the early stages.
As your ligament is healing it is important to gradually expose it to more and more load as you progress back towards your previous level of activity. It is also important to work on your proprioception (ie your subconscious awareness of your ankle position and movement) to help get you back to playing sport while minimising your risk of re-injury.
Your physiotherapist can initially help diagnose your injury (which may include other, minor, associated injuries), help reduce the swelling and pain more quickly, and guide you back towards optimal functioning of the ankle so you can return to your previous level of activity. However as your rehab progresses there is a strong reliance on you to be performing a home exercise program to improve as quickly as possible.