The main problem with the classic ‘front pack’ or more descriptively named ‘narrow-base carrier’ is exactly that. The narrow base. It does not support your baby from knee to knee and it certainly doesn’t hold them in the straddle squat or M position that is best for their developing hips in the first 18 months – 2 years of their life. The International Hip Dysplasia Institute explains the problem with the hang leg position. These ‘narrow-base carriers’ are cheap and simple to use. The manufacturers are also very good at marketing, in some cases. If you can use a better carrier (link to info on what is better), then please do. If you have one and want to use it here is a way to improve it.
Some ‘front packs have no waist band at all. These are not so comfortable for the wearer and still pose a problem for the baby. This blog post from Fine and Fair shows how you can use a scarf to improve the leg support and positioning for your baby and distribute the weight for you as the wearer.
Have a play around with your narrow-based carrier and a scarf. You will find a way to better position and support your baby’s legs.