hi
thank you for providing the brief history of you.
A thorough neuromuscular assessment is advised.
Based on your history, due to performing of the zumba, the mechanism of the injury has to be understood, Due to performing zumba for long hours, there will be a possibility of the injury of the soft tissues in the knee as well as the
lumbar spine. As, your age is 58, you may have degenerative changes in the joints and soft tissues. So, stopping Zumba for a week will be advised. Also, performing the thorough neuro musculo skeletal assessment by a ortho, the weakness in the muscles can be determined, if required the ortho may ask for an
MRI of either the knee or the lumbar spine as you have burning sensation behind the knee.
The burning sensation in the knee or behind can be due to
ligament injury , which needs a thorough assessment. Also, you have
numbness in the calf muscle and discomfort in the tail bone, this can be the lumbar spine pathology for which the symptoms are arising.
I will recommend to undergo a clinical orthopedic musculoskeletal assessment and an MRI of knee and spine to help you further.
Physical therapy will be recommended by your ortho and zumba will be stopped as well.
Recovery with physical therapy will help you regain the normalcy in 2-3 weeks since you are an active person.
Regards
Jay Indravadan Patel