Cranioplasty


- just like for a decompressive hemicrani - when you're making a giant trauma flap incision, you have to think about positioning such that you can reach the back of the head/most posterior aspect of incision. If someone has excellent neck mobility, you can just put them flat and turn head all the way over. If someone doesn't have good neck mobility (ie. c-collar, really old, arthritis, contractures) then you put a bump under the shoulder to get you access to back of head. similar principle for shunt - shoulder bump to straighten out neck for optimal tunneling.
- putting someone on a horse-shoe means that you can reach more posterior around their head more easily - think about your hand/wrist position relative to head vs them being flat on a table, and having the table block you
- shave around the incision area only
- cover eyes well with tegaderm, and then again with the 1000 drape, put drape as low across brow as you can to get the biggest field, but make sure to shield eyes - chlorhexadine is very caustic to corneas
- stuff xeroform into the ears only if you intend to use a chlorhexadine prep - it is ototoxic. if you are painting betadine or using alcohol only this step is skiappable
- prep and drape wide - you will have to tunnel a drain out of your flap
- feel bone edges under incision - if you have bone under incision you can cut all the way down. if you do not, you have to be careful - go thru skin with knife and then carefully bovie/dissect because its scalp - dura - brain. you will definitely not have any bone over the squamous temporal bone, because if you did a good decompression originally, you put a burr hole right at the pterion/over root of zygoma, and you kerrison'd all the way flush to the floor of the middle fossa for good temporal lobe decompression.
- for temporalis muscle, carefully dissect it off the dura - if you don't dissect between temporalis muscle and scalp, you can have a better chance of not causing a frontalis palsy. this is also a good place to find the bone edge and begin to develop the plane between periostium and dura.
- if you are lucky, there will be a good plane between periostium and dura, and you can follow that plane all the way around - you are not done until you see all bone edges. Put screws into the bone flap, push it flush all the way against anterior aspect of bone. if temporalis muscle is large and  healthy, you can just close (fascia on fascia) anterior temporalis muscle against posterior. If its kind of bad looking, consider putting in a mesh over the cranial defect where temporal bone used to be, to buttress it and prevent a hollowing defect later on.
- if you are not lucky, the whole thing will be scarred down and socked in and you just have to create a plane - find the bone, do not violate dura.
- leave a subgaleal drain, use hemovac (same width of drain all the way around vs JP which is a wider drain; HMV hurts less coming out, creates a smaller hole to close when removed). Always leave drain because it will bleed a lot and you will not be able to use aggressive electrocautery because otherwise it won't heal well.
- tunnel your drain before you close, tunnel it outside of your flap becusae it will heal better. do not sew in drain until you finish closing, otherwise you'll shift the position of the drain in head and where you tunnel it out may not be as sterile as the rest of your field so do that last.
- close galea with 3-0 vicryl with C-23 needle
- close skin with either absorbable sutures or staples - for healthy people who will heal well, choose absorbable - it looks nicer, plus you don't have to hurt people 2 weeks later when you take them out. If there is any question about whether someone will heal an incision though, use staples - you can hypothetically leave staples in forever. also they are faster.
- if you are struggling to close, either because scalp is really scarred or tight, consider nylon sutures with horizontal mattress-  you can use it to pull the scalp incrementally closer together