Check for manufacturers catalogue and select motor which can have more than 10 kg of holding force. It also depends on what kind of accelerations will you allow. You need to give more information about it.

You can check the Robotis company. They produce well actuators!! we have been using their production in several past years. There are different actuators with different torque that can be used for your purpose. So try their website, you can find the best.

http://www.robotis.com/xe/dynamixel_en

http://www.robotis.com/xe/DynamixelPro_en