To Protect the Wound
Given prompt veterinary attention, punctures that don’t reach the synovial structures have a good chance of healing completely with no complications.
If the wound doesn’t require surgery, your vet will clean it thoroughly via lavage and may culture it to determine which antibiotics may be needed. A tetanus shot may also be given.
At that point, some sort of protection will be required to keep the wound clean. Options include: Bandaging secured with duct tape. A protective boot with bandage underneath. A shoe with special pad or plate.