shinfin™ swim fins are used as fused ankle swim fins because they can be fitted a bit higher on your leg to avoid hitting your foot.
Customers with fused ankles generally find it better to wear shinfin™ swim fins a little bit higher up the leg than usual, perhaps with the fin tips somewhere near the base of the toes or even a bit higher. Please experiment to find the best height and orientation around the leg. shinfin™ swim fins are quite flexible and adaptable to fit at different positions. An angled foot will still cause some drag in the water but shinfin™ swim fins will reduce this.