How could one differentiate whether ankle pain is due to ligament or muscle injury in a physical examination?

Examination: Best way to tell is by examination plus an MRI to confirm. Ankle ligaments connect the tibia and fibula to the talus and heel bone. They are located on the inside and outside portion of ankle joint. They hurt when they are torn and if completely will give a sense of instability with the pain. Only one muscle crosses the ankle joint usually pain is from a tendon problem not the muscle attached to i.

Does it matter: It is hard for an individual to tell them apart, one way is to test muscle strength, a doctor can "stress" the ankle to be better able to distinguish. X-ray can distinguish fractures but not soft tissue however the treatment is the same, rest, ice, elevation, compression, perhaps an ankle splint for a few weeks, not ace bandage.

Ankle pain: An exam reveals what is injured. And there is more than one muscle that crosses the ankle joint. If only one muscle crossed that joint , how would we have inversion dorsiflexion plantarflexion and eversion ? One muscle cannot do all of that. I can think of 7 in the time it took me to write this.

Ligament vs muscle : In a pe it is very easy to differentiate muscle vs ligament injury, passive range of motion exam can determine ligamentous tears active range of motion exam can determine muscle injuries.