I Have Just Noticed A Band Of Depression Half Way

I have just noticed a band of depression half way up my right calf muscle. I have had posterior tibial tendonitis and subconsciously altered my gait. I wore a space boot for two months but have been wearing normal shoes for one month now. I think my gait is normal now apart from when I am barefoot. I worry about muscle atrophy since this is a symptom of ALS. What do you think?