German Pinschers are generally healthy, but like all breeds, they're prone to certain health conditions. Not all German Pinschers will get any or all of these diseases, but it's important to be aware of them if you're considering this breed.
If you're buying a puppy, find a good breeder who will show you health clearances for both your puppy's parents. Health clearances prove that a dog has been tested for and cleared of a particular condition.
In German Pinschers, you should expect to see health clearances from the Orthopedic Foundation for Animals (OFA) for hip dysplasia (with a score of fair or better), elbow dysplasia, hypothyroidism, and von Willebrand's disease; from Auburn University for thrombopathia; and from the Canine Eye Registry Foundation (CERF) certifying that eyes are normal. You can confirm health clearances by checking the OFA web site (offa.org).
Hip Dysplasia: This is an inherited condition in which the thighbone doesn't fit snugly into the hip joint. Some dogs show pain and lameness on one or both rear legs, but others don't display outward signs of discomfort. (X-ray screening is the most certain way to diagnose the problem.) Either way, arthritis can develop as the dog ages.
Cataracts: Cataracts cause opacity on the lens of the eye, resulting in poor vision. The dog's eye(s) will have a cloudy appearance. Cataracts usually occur in old age and sometimes can be surgically removed to improve vision.
Von Willebrand's Disease: Found in both dogs and humans, this is a blood disorder that affects the clotting process. An affected dog will have symptoms such as nosebleeds, bleeding gums, prolonged bleeding from a surgery, prolonged bleeding during heat cycles or after whelping, and occasionally blood in the stool. This disorder is usually diagnosed between three and five years of age, and it can't be cured. However, it can be managed with treatments that include cauterizing or suturing injuries, transfusions before surgery, and avoidance of specific medications.

Danixaris - German Pinschers UK