Ray amputation is a good option in cases of useless finger or stump. Although index ray amputation decreases grip strength, it does not cause any major impairments to usual activities because its role can be adopted by the third finger. The long finger, though, loses its central position in the hand after the procedure, leading to a less natural appearance, the cosmetic aspect of the procedure is highly acceptable.
Therefore, to improve the aesthetic outcome of index ray amputations, the length of the third metacarpal is reduced by shortening osteotomy. A dorsal approach with a straight incision is performed with elevation of the periosteum along the metacarpal. A transverse section of the bone is removed using a power saw and the distal metacarpal is proximally slided and a 2 mm plate is used to stabilise it. The point of osteotomy is selected at the proximal portion of the diaphysis.
The procedure is generally performed on patients after plate removal due to irritation or if the patient feels uncomfortable and unsatisfied with the aspect of the hand.

In several cases, third metacarpal osteotomy is a good option to improve a four-finger hand appearance, with the long finger in a central position. However, since there are certain risks of complications, the procedure is recommended only for patient with a high demand of aesthetics.
References
Third Metacarpal Shortening Osteotomy to Improve Hand Appearance after Index Ray Amputation https://clinmedjournals.org/articles/tcr/trauma-cases-and-reviews-tcr-1-018.php?jid=tcr