Over the past few weeks I’ve had a number of people in the office tell me that they heard you should never cut a nerve because it would grow back and cause more pain. I have always been baffled by this comment since nerves can be repaired, reconstructed and dealt with much like blood vessels and bones. Obviously, there are differences in that, for example, you would never use plates and screws on a nerve like you would for a long bone (e.g. the femur – thigh bone). Moreover, if you think about it, what would happen to all of those poor souls whose nerves are injured and cut in accidents? Would they be doomed to a life of numbness and pain? Of course not. So let’s delve into this issue a bit more.
When a nerve has been permanently injured and a piece of that nerve must be removed, there are several options for repair. Ideally, a primary repair (i.e. putting the ends back together directly) would be performed, but this maneuver is only possible in certain specific situations such as when there has been a sharp cut (e.g. with a piece of glass), very little nerve is actually missing and relatively little time has elapsed from the injury to presentation. If a primary repair is not possible, there are other options including repair with nerve conduits, nerve grafts (both autologous [i.e. from the person themselves] or exogenous [e.g. cadaveric]) and perhaps even nerve transfers. Similarly, if a sensory nerve is transected and implanted into a muscle, the majority of patients do well albeit with possible numbness in the former nerve distribution. However, in some cases of nerve transection and implantation, just like in the cases of nerve repairs following injury, the procedure does not go as planned and numbness, loss of function and/or pain remains. In some of those cases a neuroma forms. So now what?
Well, one of the best things you learn as a plastic surgeon and one of the things that makes our training unique (admittedly I’m biased) is the ability to use surgical principles in creative ways. For example, you can learn all sorts of flap and graft techniques for facial reconstruction following removal of skin cancers, but if you really think about it, everyone’s face is different. Their skin quality, skin amounts, the location of the holes left by tumor removal, the orientation of those defects, the degree of exposed underlying structures are absolutely unique in every case. Therefore, the plastic surgeon must apply the principles s/he has learned and create a reconstructive plan that is similarly unique in each case. The same is true if a neuroma forms. As we noted above, there are several options for nerve injuries and those principles can be applied to the treatment of neuromas.
If a nerve was happily ensconced in a muscle, but was jarred loose by a subsequent accident, then that nerve end may simply be found, freshened and re-implanted further into a muscle. Another treatment option for a post-operative neuroma is to perform an end-to-side repair of that nerve to another sensory (or perhaps even motor) nerve. We do these types of re-innervation procedures to help amputees power the newer myoelectric/bionic prosthetics you may have seen on TV. Yet another option is to excise that neuroma and connect that new nerve ending to a long cadaveric nerve graft (i.e. an allograft). In this case, the surgeon would be utilizing the principle of distance in that it is unlikely the cut nerve would actually grow all the way through the entire graft and hence the end of the allograft would be quiescent and unlikely to cause further pain. So you see, there are almost always ways of dealing with issues that arise. In other words, a neuroma is not necessarily the end of the story.