The causes of front limb lameness in dogs vary but often are the result of strains, bruises or other minor injuries, according to 2ndChance.info. Thorns or other sharp objects stuck in paws can also cause limping. More serious problems include arthritis and tumors in the bone.
Causes of limping that are obvious with a visual inspection include foreign objects and visible injuries, such as lacerations or sores, states MedicineNet. These may be visible in the pads, but sometimes hide in the webbing between the dog's toes. Overgrown nails can also cause pain and limping, as noted by 2ndChance.info, as can broken nails or nails with excess wear and an exposed quick. Swelling, pain or sensitivity may also be apparent higher on the limb after strains or other injuries.
Dogs can also suffer from a condition called osteochonritis dissecans that affects the shoulder or elbow joint, according to 2ndChance.info. This occurs when a small piece of cartilage tears free and is loose within the joint. Surgery may be necessary to remove the torn piece. This can occur during a young dog's growth or after trauma.
Young, growing dogs may also occasionally suffer from growing pains, also known as panosteitis, as reported by 2ndChance.info. These pains are usually short-lived and go away on their own. German shepherds are prone to the condition.