Tenosynovitis is the earliest stage of a tendon problem.
It can be excessively painful for what it is, but because it is the earliest stage of a tendon problem, it is also easy to manage if gotten on top of quickly.
There are a variety of ways to manage this problem including supports with tape, orthoses, supports, anti-inflammatories, exercises, draining the fluid and injections.
You do not typically need any imaging to confirm this, but it can be helpful. This condition can often be quite easily daignosed with nothing more than a detailed history.
A type of inflammation affecting the tendon sheath. The tendon sheath allows the tendon to move freely without friction against surrounding structures.