10 cm on the femurs is unsafe for anyone unless their starting height is around 190 cm before limb lengthening surgery. The maximum safety standard is 8 cm on the femurs, and to achieve this goal, it is advisable to have a decent starting height of at least above 5’5 / 165 cm and good flexibility before the surgery. Most individuals start experiencing issues after 4-5 cm on the tibias, which is similar to what was mentioned earlier.
In general, it is wiser not to exceed safe limits and maintain good health rather than jeopardizing functionality for a minimal gain of 1-2 cm. Such a small increase is hardly noticeable in reality, and having a good posture can provide a similar enhancement.
May I ask about your starting height?
