Intramuscular buttock implants is viewed in the U.S. as the most successful long term implant buttock augmentation method. Despite the reduction in complications with this pocket location, as opposed to that of the subfascial, it is still not popular or commonly done amongst plastic surgeons. The reason is that the anatomic dissection is not easy nor is there a completely standard technique for performing it. It is also a partially blinded procedure carried out in an unnatural or non-anatomic plane of the thick gluteus maximus muscle.
It takes anatomic confidence to dissect into the midst of the gluteus maximus muscle where electrocautery control of bleeding can not be done. Multiple dissecting instruments exist for doing it from duckbill dissectors to wide malleable retractors. While these help separate the muscle and create a path for implant placement there is no accurate way to know how big the created pocket is vs the size of the implant one wants to place into it. And using the desired implant to be placed back and forth as a sizer is not a good technique as it increases the risk of postoperative implant infection.
Gel breast implants sizers can be used to test the intramuscular pocket size, and are easier to get in and out of the pocket than a solid implant, but their compressible form makes them weak dissection devices.
The safest and effective pocket dissectors and sizers are wet lap sponges in my experience. They can be wetted with Betadine or antibiotic solution and each lap sponge when compacted together is the equivalent of about 150ccs of volume. When packed into the pocket it is firmer than a gel sizer which makes it useful as a dissection device for continued pocket development if needed.
The goal is to get the intramuscular pocket packed with enough lap sponges so their volume is equal to that of the volume of the implant to be placed. In this case a 400cc implant requires the packing of 3 lap sponges per side into the intramuscular pocket.
With good lap sponge volume to create the full pocket the buttock implants can be placed while achieving a tension free muscle closure over them
One of the important factors that makes any surgical method to be used consistently is a reliable technique to perform it. The intramuscular dissection in buttock implants poses challenges for which the use of lap sponges provides a safe and effective method for doing so.
Dr. Barry Eppley
World-Renowned Plastic Surgeon