What are Aseptic Femoral Head Necrosis? Aseptic femoral head necrosis can affect any breed of dog, but it typically develops in smaller breed dogs. This condition can be caused by damage to the hip joint or can develop due to a genetic condition. Either way, most dogs slowly develop symptoms over a period of time with a slow progression of worsening symptoms. If your dog is diagnosed with aseptic femoral head necrosis, there are a few therapies veterinarians can offer to give your dog pain relief, but surgery is the most common fix. Aseptic femoral head necrosis in dogs can appear with no known cause. If your dog is having trouble walking or experiencing any sort of pain in his hind end, you should take him to a veterinarian for evaluation. Symptoms of Aseptic Femoral Head Necrosis in Dogs If your dog is suffering from aseptic femoral head necrosis, he may or may not develop some of the symptoms listed below: Irritability Chewing at the hip or flank Pain Medial patella luxation Progressive hind limb lameness, unilateral or bilateral Restricted joint movement Muscle atrophy of affected limb Inability to bear weight on the affected leg Crepitus of the hip joint.