In waistline narrowing surgery the distal sections of the lower free floating ribs are removed to allow the waistline to collapse inward. While the ribs are not the only structures supporting the width of the waistline they are the most rigid. Without rigid support the soft tissue layers of the waistline eventually contract down/inward, very much like the skin contraction that occurs after fat removal from liposuction.
In removing ribs for this aesthetic purpose there is more to it than just cutting the rib at a certain point and removing it. The bony rib needs to be circumferentially dissected off from its enveloping soft tissue in the subperiosteal plane. One of the key points in this dissection is to release the neurovascular bundle from the costal groove on the underside of each rib. In this neuromuscular bundle is the vein-artery-nerve from top to bottom. Besides the risk of bleeding from injury to the vascular components of the bundle, injury to the nerve could result in chronic pain along its distribution to the chest wall. Therefore a good rib removal leaves an intact bundle behind.
To help with postoperative pain management an anesthetic nerve block would be useful for each rib. A very effective way to do is to place the anesthetic drug directly onto the neuromuscular bundle where it can diffuse into the nerve as well as the surrounding muscle tissues. Using a dissolvable collagen sponge it is soaked in an anesthetic agent and placed into the space where the rib was removed. The surrounding muscle is then closed over the sponge-packed rib space.
While there are a variety of topical anesthetic agents that could be used, the combination of bupivacaine-liposome suspension (Exparel) seems the most appropriate in this application. With a duration of effect between 24 to 72 hours such prolonged pain relief placed directly onto the nerve and surrounding music tissues at every rib removed is helpful in the first few days after the surgery.
Rather than leaving an empty rib space containing the neurovascular bundle the rib is essentially swapped for a dissolvable sponge that can help alleviate some of the effects of nerve and muscle trauma.
Dr. Barry Eppley