The common reasons for thick calves and thin thighs are as follows: 1. It may be caused by the patient’s own fat deposition characteristics. Some patients have their own fat deposition characteristics, when they become fat, they may first fat calf or fat waist and abdomen, so it is possible to produce the lower limbs asymmetrical situation. 2, may be due to the swelling of the calf area caused by. There are many possible causes of swelling in the calf area, such as varicose veins, blood clots inside the veins, or obstruction of the lymphatic system of the lower extremities, such as filariasis, which leads to very serious swelling in the area below the knee joint, resulting in thick calves and thin thighs. In addition, if the patient has heart, kidney or malnutrition-related diseases, may also produce similar symptoms. 3, may be due to the calf part of the muscle hypertrophy caused by. For example, if the patient has pseudohypertrophy myotonic dystrophy, it may lead to abnormal hypertrophy of the gastrocnemius muscle in the calf area, and the muscle strength is very poor, which may also produce the above symptoms.