This week’s post is the second half of a Q&A on the controversial diagnosis of pudendal nerve entrapment and the decompression surgery associated with it.
For this post, we chatted with two of the leading experts on the topic: Michael Hibner, M.D., a gynecologic surgeon at St. Joseph’s Hospital and Medical Center in Phoenix, Ariz. and Mark Conway, M.D., a gynecologic surgeon at St. Joseph’s Hospital in Nashua, New Hampshire. (See full bios below.)
Q: Can you give a brief rundown of the pudendal nerve decompression surgery?
There are four different procedures described for decompressing an entrapped
pudendal nerve: transgluteal, transischiorectal, transperineal, and endoscopic.
The two biggest competing approaches for the decompression surgery are the transgluteal, which is the one I mainly perform, and the transischiorectal.
In my opinion, the transgluteal approach appears to be the most effective technique, allowing the best visualization of the pudendal nerve and the greatest extent of decompression along the length of the nerve. The surgery that I do is very different from the original France surgery. Back then it used to take 45 minutes to an hour to complete the procedure. Today, we spend three or four hours minimum using a high powered microscope, and very precise scissors we cut every little piece of scar tissue around the nerve.
The main concern with this approach that was originally described by Professor Roger Robert in Nantes, France, was that it requires the cutting of the sacrotuberous ligament in order to get to the nerve. As a result, PTs would see a lot of sacroiliac joint instability after cutting that ligament and not repairing it. When I began doing the procedure, I started repairing the ligament. PTs around the county started noticing that when you repair the ligament you actually prevent instability of the joint, so again this surgery has gotten better and I think since we are repairing the ligament the negatives are minimized.
Click this article by Dr. Hibner in OBGyn News for a more detailed and in depth description of the nerve decompression surgery see:
Dr. Conway, you stopped using the TIR approach and now use the TG. Can you tell us why?
Firstly the decision to do the TIR was based on published case series data that showed marginally better outcomes than the classic TG approach. However, no head
to head trial was ever done so it’s impossible to state which is more effective. Also the TIR preserves the ST ligament which I felt was a big advantage compared to the classic TG approach where both the ST ligament and the SS ligament are transected.
I felt these advantages outweighed the lack of exposure of the nerve; however, with the modification of the TG approach with longitudinal spreading of the ST ligament and it’s preservation that changed. Now the superior visualization of the nerve with the modified TG approach becomes a big advantage.
Also I have done at least 20 redo operations on failed TIR surgeries with the modified TG approach and have invariably found the nerve entrapped by scar tissue at the level of remnants of the SS ligament. This is because often only a portion of the SS ligament is severed during the TIR approach.
Plus the TG approach allows the operator to do more precise nerve monitoring during the procedure using the NIMS system. Also we often find very complex anatomical situations where there is a branched nerve traversing the area, and the nerve may be perforating one of the ligaments. The TIR approach can’t really address these issues. Also I feel there is definitely less bleeding and probably fewer infections as well with the modified TG.
Q: What are other negatives of the surgery?
The postoperative course and recovery can be difficult. Cutting through muscle is painful. We try to minimize this by giving patients a pain pump after surgery, which helps with the pain for the first two to three weeks after surgery by bathing the pudendal nerve in the anesthetic, Marcaine. Besides pain control, another reason to do this is that it may help to desensitize the nerve.
Q: What are the risks of the surgery?
One risk is that the pain will not get better. The second is a one percent chance that the pain will get worse. I’ve done about 200 to 250 cases, and have never had any significant negative outcome from surgery.
Also, there used to be a risk of wound infection because the incision was so close to the rectum, but two years ago we started using something called a wound vac, which is a suction dressing on the wound that provides negative suction to the wound for five days. Since then we have had zero infections.
The greatest risk is that the surgery won’t help. I always tell patients that there is a 20 percent to 30 percent failure rate where the surgery will not help the patient at all. In addition, patients are always concerned that the surgery will make their symptoms worse. However, in my experience this hasn’t happened. But I have seen patients three years after surgery who have gotten worse, but not because of the surgery, but because the surgery didn’t help, and their condition got worse over time.
Q: What is the follow up protocol for patients who do the surgery?
Patients are in the hospital for two or three days. Many of our surgical patients are from out of town, and therefore, they stay in a local hotel for another seven to ten days. We then see them in the office to give them the okay to go home. From there, we recommend follow up with their local physician once they get home to have their incisions checked and refill pain medication. In addition, we do leave stitches in that have to be removed.
The majority of out-of-town patients do not keep in touch. We tend to hear either good news or bad news from the ones that do.
Then after that if patients do live locally, we will see them in two to three months, then every few months until they get to where they need to be.
Adds Dr. Hibner:
In addition, while surgical incisions are healing, and operative pain runs it’s course for four to six weeks, during that time we recommend only light activity avoiding sitting and minimal activity. And somewhere between eight to twelve weeks after surgery we recommend that patients reconnect with their local PT to further help heal musculoskeletal issues. Overall, we encourage patients to view recovery from surgery as their career at that time taking at least six weeks off from work if they are working. Many patients are not due to their pain.
Patients having any surgery – rotator cuff repairs, knee replacements, back surgery, all require post-operative physical therapy. It is important for patients to understand that surgery alone will never be as successful as surgery and post-operative physical therapy combined.
Over the past 13 years, I cannot count how many PN post-operative patients have called our office concerned that they were ‘re-entrapped’. While this is possible, many of these patients were not told to go PT or they unfortunately did not have access to it. When I evaluate these patients we often find myofascial impairments that are causing at least some of, if not all of, their pain. The take home message is in almost all cases physical therapy can help a patient dealing with PNE function better. And I am not just saying that because I am a PT. : )
Q: At which point is the surgery considered a success?
Usually we expect the first improvement to occur between about four or five months with a maximum of 18 months. In my view, success is what the patient considers success.
Q: When is the surgery considered a failure?
From a research perspective what is considered a positive outcome, and I’m not saying this is good for the patient, but just for research purposes an improvement of pain of 20 percent is a positive outcome. Looking at our patients, 70 percent of our patients have an at least 20 percent positive outcome.
Q: What is the goal or the expectation of the surgery?
That is a great question. It is crucial to set realistic expectations with patients. So number one what I tell patients is that you have developed PNE because you have a predisposition, and we don’t know what that predisposition is. The surgery can’t take that predisposition away.
Number two I tell them it is very unlikely the surgery will be able to make you 100 percent pain-free. There are some people who get 100%, but it is uncommon. Number three I tell them if an activity caused PNE, like biking, surgery will not likely result in the ability go back to biking. Number four I tell patients that PNE affects multiple things: pain, sexuality, sexual arousal, ability to sit, etc., and some symptoms may improve and not the others.
The ultimate goal of the surgery is to improve patients’ quality of life.
We’re trying to get these patients to have as normal life as possible, the highest level of normal function they can achieve using a continuum of treatments. You have to keep trying modalities until you get maximum result for the patient. I always tell my patients not to think of surgery as the end of their treatment.
For instance, they may need more PT after surgery or more nerve blocks. They might even respond better to a block now that the nerve has been freed up because there’s much more room around the nerve for the medication to diffuse and have a positive effect. In addition, PT may be much more helpful because the nerve is behaving better, so the effect of PT may be more profound for these patients.
Dr. Michael Hibner is director of the Arizona Center for Chronic Pelvic Pain, St. Joseph’s Hospital and Medical Center, Phoenix. He is a former fellow in advanced gynecologic surgery at Mayo Clinic, Scottsdale, Ariz., and is now professor of obstetrics and gynecology, Creighton University, Omaha, Neb., and associate clinical professor of obstetrics and gynecology, University of Arizona, Tucson.
Dr. Mark Conway is the head of the obstetrics and gynecology department at St. Joseph’s Hospital in Nashua, New Hampshire. Dr. Conway, a Fellow of The American Congress of Obstetricians and Gynecologists, heads a comprehensive pudendal neuralgia treatment center offering conservative therapies, medication management, a surgical solution to treat pudendal nerve entrapment as well as comprehensive post-operative care.
If you have any questions about either the diagnosis of PNE or the decompression surgery, please leave them in the comment section below!