Micro-invasive carpal tunnel release

In this episode of PodMD, specialist anaesthetist Dr Peter Hebbard will be discussing the topic of micro-invasive carpal tunnel release, including what micro-invasive release is, the different techniques of ultrasound guided release, recovery times, how it can help patients with failed surgical carpal tunnel release, how to refer for micro-invasive release and more.


  • Transcript
    Please note this is a machine generated transcription and may contain some errors.
    *As always, all in this PODMD podcast is intended for health professionals and the comments are of a general nature. Information given is not intended as specific medical advice pertaining to any given patient. If you have a clinical issue with one of your patients please seek appropriate advice from a colleague with expertise in the area.

    Today I’d like to welcome to the PodMd studio Dr Peter Hebbard.

    Peter Hebbard is a specialist anaesthetist with a particular interest in ultrasound guidance technology, novel techniques and medical device development. Over the last few years, he has been working primarily out of Northeast Health Wangaratta in the northeast of Victoria, and at the Wangaratta Private Hospital.

    After many years of experience, Peter is proud to have developed a system to perform superficial procedures such as carpal tunnel release under ultrasound guidance using a novel needle-based tool called the “micro iBLADE “.

    The “micro iBLADE “ procedure allows patients to get relief from the symptoms of carpal tunnel syndrome with minimal intervention and quicker recovery times. As with any new procedure, it’s carefully introduced and well monitored.

    *We do hope you enjoy this podcast but please remember that the advice here is of a general nature and is not intended as specific advice about a given patient. The views and opinions expressed in this podcast are those of the doctor, not PodMD.
    If you do have a patient on whom you require specific advice, then please seek advice from a colleague with appropriate expertise in that area.

    Peter, thanks for talking with us on Pod MD today.

    Peter: Thank you for having me.

    Question 1
    The topic of today’s discussion is micro-invasive carpal tunnel release. Peter, can you describe for our listeners what is micro-invasive carpal tunnel release?

    Peter: So microinvasive carpal tunnel release is a new technique of carpal tunnel release which is distinct from endoscopic carpal tunnel release and open carpal tunnel release.

    So it was first described in 1997, as a technique under ultrasound guidance. But since then, myself and a number of other people around the world have developed equipment and techniques in order to complete carpal tunnel release, with much less than the standard incisions involved with endoscopic or open surgery.

    So essentially what it involves, in my hands is a needle-based procedure or a needle sized tool procedure, which is inserted under ultrasound guidance deep to the transverse carpal ligament and then can be guided to cut the ligament from the inside.

    Question 2
    Are there different techniques of ultrasound guided release?

    Peter: Yes, there have been a number of different techniques of release under ultrasound described.

    There are a number of devices that are available overseas in America. There’s a device which goes under the carpal ligament and then some balloons are inflated and then a little blade can pop up and cut the ligament from the inside. They’ve also been techniques described, using endoscopic equipment, but guiding it with ultrasound rather than with the endoscope, in order to reduce the size of the tool that goes in the ligament, and that usually involves some sort of hook knife which is used for either above or below the transverse carpal ligament to cut it.

    The device that I’ve been involved with is a little blade which is sheathed inside a needle sized tool, which goes underneath the transverse carpal ligament, and then the little blade can be activated and popped up, and then cutting the carpal tunnel, but cutting the transverse carpal ligament as the tool is removed, and the whole process can be controlled and guided by ultrasound.

    Question 3
    How is it different to endoscopic release?

    Peter: So with the microinvasive release, first of all, there’s a single insertion site which is the size of a needle, and the tool that I use is introduced usually through a 14-gauge Ivy catheter. It’s the size of a 16 gauge and it goes; we use that catheter to pierce the skin. The tool itself has a blunt end and once it’s deep to the fascia it can pass under the transverse carpal ligament and underneath.

    So that’s in distinction to the endoscopic carpal tunnel release where the surgeon makes a cut in the wrist usually, and sometimes another one in the palm, and then pushes the endoscope sheath through the carpal tunnel, usually without any imaging at that stage. So all the imaging comes from the camera, which can look inside the sheath.

    Question 4
    Is it as good as other techniques of carpal tunnel release?

    Peter: So there are a number of advantages of using ultrasound guidance. First of all, I can map the anatomy accurately before we start, and I can usually image all the important nerves in the hand, including the digital nerves, the recurrent motor branch of the median nerve in particular.

    So one of the advantages of microinvasive carpal tunnel release is that I can do it quite easily in the clinic where as it requires only sort of basic levels of operating room facilities: sterile, set up benches and so forth.

    Question 5
    Is recovery any quicker or better than open carpal tunnel release?

    Peter: Yeah, so look, that’s a, that’s a very good question. And really because it’s such a new and emerging technique, there isn’t really any long-term data. Most of the worldwide carpal tunnel release is reported and they’ve now been probably maybe 2 or 3000 cases in the literature.

    I really have effectively, quite a short follow up compared to the traditional releases, so we know that the technique appears to be very good out to a number of years, but we don’t really have much in the way of figures beyond that.
    In terms of symptom relief, the techniques all appear to be effective and the audit of our patients show very high rates of satisfaction for relief of their carpal tunnel symptoms.

    There are, there are actually no reports as far as I’m aware of patients having significant recurrence, years after ultrasound guided carpal tunnel release, and there’s no particular reason to think that those figures would be any different from endoscopic carpal tunnel release, but certainly one of the advantages of the ultrasound guided technique is that by being able to image where the nerve is constricted, I can make sure that the cut in the transverse carpal ligament extends as far as it needs to, so if there’s a prominent constriction of the median nerve proximal in the wrist, then I can make sure that I extend the cut from the microinvasive release through the fascia up to that point and I have seen a number of patients who’ve presented to me after failed open or endoscopic carpal tunnel release, where it’s obvious that the incision of the of the ligament has not extended proximately far enough, and I’ve been able to complete that release approximately with good results.

    There have been studies looking at techniques of ultrasound guided carpal tunnel release and in comparison with open carpal tunnel release are showing very significant earlier return to work and return to normal function.

    And that certainly has been our experience. However, it must be said, that the experience with all the ultrasound guided techniques are fairly early still at the moment, in that they’ve only really been around for in any quantity for four or five years.
    But look, I think it’s fair to say that when you minimise the incision and only take or only cut that issue, that needs to be cut to relieve the pressure on the nerve the likelihood of quick return to function is always going to be higher than with other techniques or open carpal tunnel release.

    Question 6
    Peter, what is your own experience with micro-invasive carpal tunnel release?

    Peter: My story with performing ultrasound guided carpal tunnel release came in the context of working with our surgeons in Wangaratta who assisted me in doing the first few cases, as I’m an anaesthetist and procedural ultrasound person rather than a surgeon, so that occurred about three years ago.

    And after a slow start as we recruited patients and performed services in the public hospital in Wangaratta, we’ve now expanded out into the clinic in Wangaratta and Port Melbourne, and I’ve now done over 700 ultrasound guided carpal tunnel releases. So I sort of think I’ve got my eye in now.

    The general experience has been very positive from our patients and in fact most of my referrals and growth have come through word of mouth and I don’t think it be any exaggeration to say I’m now doing most of the carpal tunnel releases in North East Victoria and that is steadily growing, yeah.

    Question 7
    What about patients with failed surgical carpal tunnel release?

    Peter: Thank you for that question. This is I’m seeing more and more patients who are who are coming to see me having failed other techniques of carpal tunnel release and I found that in general I have been able to offer them some treatments.

    The easiest are patients to treat with failed surgical carpal tunnel release, are those in whom there’s an obvious, usually proximal constriction of the median nerve, and in those cases it’s usually enough to do a limited rerelease of the transverse carpal ligament, concentrating on that area where the constriction of the nerve is still obvious.

    There are other trickier cases of recurrent or failed surgical, carpal tunnel release, and usually in those circumstances I’ll try and hydrate a sector the carpal tunnel first under ultrasound guidance and use a stiff needle like a 16 or an 18-gauge Tuohy needle to probe the transverse carpal ligament and see if I can identify areas where it would still be constricting.

    If I can identify an area like that, then I feel confident in going back in there using the ultrasound guided technique and redoing the procedure.

    Question 8
    What is the place of this technique in the future?

    Peter: My feeling is that this technique is a considerable advance in the treatment of carpal tunnel syndrome and overtime it will replace most other techniques for performing carpal tunnel release.

    So I think it’s got a. It’s got a big place in the future. The limitations at the moment are having people who are capable of doing the procedure. Because I think the first essential step is to have someone who is used to doing uh, a lot of procedures, in their practise under ultrasound rather than necessarily are coming from a surgical background.

    Question 9
    How can you refer patients for micro-invasive carpal tunnel release?

    Peter: So at the moment I’m actually looking for people who use ultrasound a lot in their practise and want to learn this technique.

    The COVID-19 pandemic has had quite a significant effect on that process of trying to get out and teach people this technique because we haven’t had the opportunity to have any face-to-face meetings for so long, but I think as a technique having done a considerable number myself, having seen the results and seeing how happy the patients are, particularly those patients who’ve had maybe the other side done with an open or endoscopic technique. Seeing the way in which uh, they recover much quicker after the ultrasound guided technique, that leads me to the conclusion that in 10 years’ time this will be the standard technique for carpal tunnel release, but it is going to take time that maybe it’ll be 20 years. I don’t know, but it will it will get there.

    Unfortunately, at the moment I’m the only person doing this in Victoria and referrals can just be made in the thethe normal sort of fashion through to my microinvasive clinic which is in Port Melbourne or Wangaratta. But overtime I hope that there will be a a lot more people able to offer this this procedure and the referral pathways will become much easier, but at the moment I still practise in anaesthesia but my carpal tunnel and other microinvasive procedure practice is growing rapidly.

    Concluding Question
    Thank you for your time here today in the PodMD studio. To sum up for us, could you please identify the three key take home messages from today’s podcast on micro-invasive carpal tunnel release?

    Peter: 1.Well firstly, a microinvasive carpal tunnel release is a novel technique, and it is different to endoscopic carpal tunnel release.

    2. Secondly, it’s early days, but the early indications are that the treatment is effective and safe and provides earlier return of function to the patients.

    3. And the third is that, like any technique, it’s not a magic bullet.
    And like other carpal tunnel release techniques, it can sometimes have a slow recovery or progression to chronic pain.

    Thanks for your time and the insights you’ve provided.

    Peter: Thank you

*As always, all in this PODMD podcast is intended for health professionals and the comments are of a general nature. Information given is not intended as specific medical advice pertaining to any given patient. If you have a clinical issue with one of your patients please seek appropriate advice from a colleague with expertise in the area.