Spencey, I have the same problem (almost a 2 cm leg difference), and a podiatrist can help with these issues. There's often more things that can be connected to this, such as how you stand on your feet, the form of your feet (the arch specifically), and back pains caused by your lower back having a slight twist to compensate for the turning of your hips. Insoles can work to help with all these things (not necissarily improve, but compensate).
Spencey, I have the same problem (almost a 2 cm leg difference), and a podiatrist can help with these issues. There's often more things that can be connected to this, such as how you stand on your feet, the form of your feet (the arch specifically), and back pains caused by your lower back having a slight twist to compensate for the turning of your hips. Insoles can work to help with all these things (not necissarily improve, but compensate).