hi,
Thank you for providing the brief history of you.
A detailed clinical musculoskeletal assessment is advised.
As mentioned in your history about the normal x-ray and pain still persists while bending the knee, than an ortho clinical assessment is needed, as your pain sounds more of a
soft tissue injury than a bony one. So x-ray cannot show anything except the bones which appeared normal. Your ortho may also advice you for
MRI of knee, which will help in addition to see the soft tissue status. As pain during straightening the knee is related to the soft tissue injury and should get assessed.
Based on the diagnosis, you will be recommended for simple pain killers and
physical therapy.
With physical therapy, your pain will reduce by use of therapeutic
ultrasound therapy and
TENS therapy. Also, exercises will be performed to regain the ROM of the knee joint and also the strength of the muscles.
In my clinical experience, I have seen cases with such injuries, and they respond well to the medication and physical therapy. By 2-3 weeks of time, they have optimum functionality without pain.
Regards
Jay Indravadan Patel