Hi, German Shephards are known for having Spinal Muscular Atrophy.
I knew of a top performance Golden Retreiver who licked her legs raw. It was a neurotic behaviour, she was so "overtrained" I doubt this bitch could toilet without being commanded. If a dog is licking the paws excessively the first thing to do is examine the feet closely and if there is a reddish brown colour or grease in between the toes then it is simply a fungal infection which is easily treated. Continual recurrence is general linked to food allergy but may also be contact allergy. It can also be advisable to check a dog's thyroid panel, Berners are generally on the low side of normal but quite often a diagnosis of hypothyroidism and subsequent supplementation can help with skin and coat issues. Another thing is to keep nails short because discomfort with long toenails turning can aggravate sensitive feet when walking on hard surfaces. Also be mindful of the surface your dog is exercising on, too much pounding the pavement can make the pads sore and the toe joints ache. Rose