Let’s discuss an elephant in the room of operating room anesthesia–the association between peripheral nerve blocks and nerve injury.


The use of peripheral nerve blocks has crescendoed in anesthesia practice, stimulated by the use of ultrasound-guided visualization of nerves. There are growing economic industries in ultrasound machines, ultrasound block needles, and in anesthesia personnel who bill for this additional optional procedure on orthopedic patients.

Ultrasound allows us to visualize the nerves, but there are no data demonstrating a lower neurologic complication rate with this ultrasound technique.(Liu SS, et al. A prospective, randomized controlled trial comparing ultrasound versus nerve stimulator guidance for interscalene block for ambulatory shoulder surgery for postoperative neurological symptoms. Anesth Analg. 2009;109:265-271).

The incidence of nerve injury following peripheral nerve block is low, but not zero. Per Gadsden, the mechanism of permanent nerve injury is felt to be either needle trauma, or toxicity of local anesthetics. In a review article by David Hardman MD MBA, of the University of North Carolina, the incidence of permanent injury rates, as defined by a neurologic abnormality present at or beyond 12 months after the procedure, ranges from 0.029% to 0.2%. This reviewed data came from old studies, dating from 2001 – 2012. There are no more recent published studies of large populations. Multiplying this 1/3000 to 1/500 incidence by the tens of thousands of nerve blocks performed yearly leads to a significant number of permanently damaged nerves.

This is a problem.

I would never agree to have an ultrasound-guided brachial plexus, femoral or popliteal nerve block performed on me.

Why not? Because I need my hands and upper extremities to function normally in order to earn a living as an anesthesiologist. Because I’m also active in a number of sports, and I need my legs and lower extremities to function normally in order to walk, run, and function in athletics.

For me, the acceptable incidence of permanent nerve injury to my limbs is zero. The incidence of permanent nerve injury with general anesthesia should be zero. Of course, if the surgical team is negligent and positions me in a dangerous posture during general anesthesia, there could be a compression or traction nerve injury, but this is exceedingly rare in competent hands. Of course, if an orthopedic surgeon is negligent and compresses, stretches or damages a nerve, there could be nerve injury, but again this is exceedingly rare in competent hands.

If I’m wary of having a peripheral nerve block performed on myself, then I must be wary for my patients as well. Every individual needs their upper and lower extremities to function normally to perform every day tasks, to perform their jobs, or to enjoy their leisure or athletic activities.

I contend that, as of 2018, the incidence and number of permanent nerve injuries during this era of ultrasound-guided nerve blocks looms larger than any medical literature confirms. Why is this? I believe there are several reasons for the under-reporting of nerve injury following peripheral nerve blocks:

  1. Time lag in published data. The data in the medical literature regarding peripheral nerve injury following nerve block is old. In a lecture on this topic by David Hardman MD MBA at the American Society of Anesthesiologists (ASA) national convention in San Francisco, none of the data regarding nerve injury complication was more recent that 2007. Recent data is still unreported, and remains to be analyzed.
  2. Time lag in Closed Claims data. The ASA Closed Claims data always lags behind the occurrence of complications. A typical malpractice lawsuit takes a long time (e.g. 4 – 7 years) to come to a conclusion. The ASA Closed Claim database may be 10 years or more in arrears before it is finally published.
  3. Some peripheral nerve injuries never get reported to anyone. Either the patient never informs the physician, the case never gets tallied in any database, the physician never informs any quality assurance (QA) committee, or the case meets its termination in a QA committee discussion that goes no further.
  4. No one publishes case reports of their complications. Do you think an anesthesiologist is motivated to publish a case report in which they had permanent nerve injury of the brachial plexus following an interscalene nerve block for shoulder surgery? Of course not. He or she wants that case buried deeply, with as few people as possible knowing. No one publishes their dirty laundry, hence the medical literature is lacking in adverse case reports.
  5. Academic professors specializing in regional anesthesia have little interest in publicizing data that could damn or minimize the importance of their chosen subspecialty. A physician who makes his or her living performing, teaching, and writing about a hammer has a conflict of interest when it comes to speaking out on the dangers of wielding that hammer.

In my role as a peer review physician, quality assurance committee member, expert legal witness, and simply as a physician in a busy medical system, I’m aware of more than a dozen patients who already have permanent nerve injury following an ultrasound-guided peripheral nerve block. None of their case histories has been published, and none of their cases have appeared in a published series of nerve injury complications.

Is there a cover-up ongoing regarding permanent nerve injury? There is certainly no publicizing of these complications.

Let me give you an example of another anesthesia technique that was associated with permanent nerve injury: In the 1990’s we routinely used hyperbaric 5% lidocaine for spinal anesthesia. Lidocaine had the advantage of supplying short (1 – 1 ½ hour) spinal anesthesia for simple cases such as cytoscopies, urethral surgeries, perineal surgeries, and inguinal hernias. Case reports of cauda equina syndrome emerged, in which some lidocaine spinal anesthetics were associated with inflammation of the distal spinal cord (cauda equina), which caused permanent lower extremity nerve injury. Because of this risk, the use of lidocaine spinal anesthesia disappeared. The risk of nerve injury was real, and the risk was too daunting to continue using that anesthesia technique.

Expect a similar story to evolve over the coming years regarding the current burgeoning practice of peripheral nerve blockade. “Complications of Peripheral Nerve Block,” an article published in the British Journal of Anaesthesia in 2010, stated that “complications of peripheral nerve blocks are fortunately rare, but can be devastating for both the patient and the anaesthesiologist.” Indeed, for the patients whose nerve injury does not resolve it can be a tragedy.

In his lecture on nerve injury complications of peripheral nerve block delivered at the 2018 ASA national convention in San Francisco, speaker David Hardman, MD MBA told a standing room only crowd of anesthesiologists that if your patient develops a permanent nerve injury following a peripheral nerve block, “you will be sued.” Why was there a huge crowd for this particular lecture? I believe it’s because many anesthesiologists are aware of the occurrence of nerve injury, and aren’t sure what to do about the incidence of ultrasound-guided nerve blocks in their practice.

No one wants to be sued, but per the Hippocratic Oath we must first do no harm. The real crisis is not that an anesthesia provider gets sued, but that the patient will go the rest of their lives without the normal use of their arm or leg.

General anesthesia has risks. Adding a regional anesthetic to a general anesthetic adds a second set of risks. At times regional anesthesia is indicated. I still perform peripheral nerve blocks on select patients, and I believe peripheral nerve blockade still has utility in anesthesia practice. I believe ultrasound-guided peripheral nerve blocks are indicated:

  1. If the scheduled procedure will cause significant post-operative pain, e.g. a total shoulder replacement.
  2. If parenteral narcotics are unlikely to relieve the pain satisfactorily, e.g. a total shoulder replacement, or you are doing a painful procedure on a patient who consumes chronic narcotics, and who will be tolerant to narcotic analgesia.
  3. If I explain the non-zero risk of permanent nerve injury, e.g. a risk of 1 in 3000 patients, and the patient both understands this risk and consents to proceed.

Seducing a patient into accepting a peripheral nerve block by minimizing the chance of permanent nerve injury with phases such as, “nerve injury is very, very rare,” or “nerve injury is very uncommon, and it usually resolves,” is deceptive medical practice. If that patient later develops permanent nerve injury, you can expect to be sued. A 2007 survey of academic regional anesthesiologists indicated that nearly 40% of respondents did not disclose the risks of long-term and disabling neurologic injury prior to performing peripheral nerve blocks.( Brull R, et al. Disclosure of risks associated with regional anesthesia: a survey of academic regional anesthesiologists. Reg Anesth Pain Med. 2007;32:7-11)

It’s better to tell the patient the truth, and risk the following dialogue:

Anesthesiologist: “The risk of permanent nerve injury after this nerve block is very low, but it’s not zero. A ballpark incidence of the chance of permanent nerve injury to your arm (or leg) is one patient in 3,000.”

 Patient: “A one in 3000 chance that I could have permanent nerve injury? I don’t want to take that chance. Skip the block.”

Yes, you might lose the opportunity to do the block, but that’s what informed consent is all about. It’s your duty to explain the risks, the benefits, and the alternatives. In Hardman’s article, the author states that he circles the words “nerve injury” on the anesthesia consent for peripheral nerve block, and he has the patient write their initials next to it, to document that they have read it and understand the risks.



  2. Liu SS, et al. A prospective, randomized controlled trial comparing ultrasound versus nerve stimulator guidance for interscalene block for ambulatory shoulder surgery for postoperative neurological symptoms. Anesth Analg. 2009;109:265-271).
  3. Brull R, et al. Disclosure of risks associated with regional anesthesia: a survey of academic regional anesthesiologists. Reg Anesth Pain Med. 2007;32:7-11.


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  1. Hello,
    I had a reverse total shoulder joint replacement because the first normal surgery failed due to subpar physical therapy outfit selected by the hospital. Same year, had to have the second shoulder surgery before operaton was consoled by an anethesiologist about the nerve block. Given my intolerance to pain and the criminalization of opioid based pain relievers (including the morphine pump previous given post operation which worked great)l. This was performed at Jefferson University Hospital in Philadelphia PA. Now I have permanent damage to my left hand. The numbness in 1/ of my hand and fingers never went away. It is permanent. Had DEA minded its own business and allowed Drs. to help patients appropriately, I would have full use of my left hand. Because I am retired. this doesn’t interfere with making a living or raising children. But I firmly believe the hideous over reaction to the abuse of drugs and overdoses of heroin/fentynl and drug addiction in America is not in any way reduced by banning the best, most effective, and low cost method for treating acute pain following surgery.

    1. I’m sorry for your outcome, for the numbness in your hand and fingers.
      I must say that in a complex case like yours, in which a total shoulder was redone, there are multiple causes for having permanent numbness after the surgery. It may very well be that the surgery itself caused the nerve damage. I agree with you that the trend to avoid narcotics has led to aggressive use of nerve blocks. But a total shoulder surgery is a very painful surgery, and the standard of care would be to use a nerve block to control extreme postoperative pain. I believe for you the nerve block was indicated, and I believe the anesthesiologist should have given you an informed consent that included both the benefit of the nerve block, as well as the risk, which included the risk of permanent nerve damage.

  2. This post looks to have escaped some deserved push back since a lot of regional procedures reduce anesthetic need and thus reduce overall anesthetic risk rather than compound it. I suppose maybe not in Silicon Valley, but most everywhere else the age and health profiles of elective ortho patients would astonish the uninitiated, with most people’s angst coming from lack of candor about lingering CNS effects from GAs still being sold as “going to sleep” rather than a more apt analogy of drinking a fifth of vodka and passing out. Granted a fit tennis playing anesthesiologist with lots of cognitive capabilities to spare can take a few of these in stride. But your 80+ yo mother, not so much, and we’re talking every time, not once out of 3000 (even if that questionable number were to be accepted)…

    1. Thanks for your email. I agree that regional blocks do reduce narcotic and anesthetic needs. I use regional blocks selectively, and am glad to have them in my toolbox. The issue regarding this post is that there is a real risk of permanent nerve damage, and patients need to receive verbal informed consent about this before the anesthetic starts. I believe many anesthesiologists minimize or don’t mention that risk. I’m aware of a dozen or more patients whose life is permanently damaged because they have a leg or an arm that now has bona fide permanent nerve damage after a modest orthopedic surgery. For most healthy sports medicine patients the benefit of a nerve block is that they will need less Vicodin or Percocet for the first couple of days. The 1/3,000 risk is that they will never be able to play their sport again. If you doubt the 1/3,000 number, encourage your academic regional anesthesia specialists to prospectively study the issue and get real data. The incidence is not zero. The community of regional block specialists loves doing blocks, and many in the community of regional block specialists at this time are promoting what they do while minimizing the risks of permanent damage. I play sports every day. I’ve had two shoulder arthroscopies and took a total of two Percocet for those surgeries. Personally I would have a nerve block if I was having a total joint replacement. I would not incur the nerve damage risk for a mere arthroscopy (which is most of what ambulatory orthopedic practice is.) Nerve blocks are not going away, but everybody doesn’t need one and an honest discussion of risks should be the standard of care. May you never have a 22-year-old athlete contact you after their foot surgery complaining that they can no longer run, or a 28-year-old professional athlete contact you after their surgery complaining that they can no longer throw a football. Keep in touch.

  3. thank you for publishing this. I have a muscle drooping in my face from a scalene nerve block from shoulder surgery. I think they severed my nerve, my shoulder is better and now my muscle is permanently drooping. I’m surprised to see someone writing about this. Thanks

    1. Stacie,
      I’m sorry to hear this. I believe patients need to be better informed of the risks of nerve blocks beforehand. Many would never consent. I few hours of pain is preferable to permanent nerve damage. I sincerely hope that your deficit improves with time.

  4. My husband had Left shoulder surgery January 2022. He had a pain block. The week after surgery he developed tremors in his left hand. Neurologist said it was Parkinsons. We argued. He was fine before the surgery. mri, bloodwork, came back negative for Parkinsons. EMG was only a pinched nerve in elbow. Waiting for the spinal cord mri to come back. We actually have no idea why they are not asking for a shoulder mri. We found so many other people who have the same issue after the pain block for shoulder surgery and have started to find more on Parkinsons sites who were diagnosed but it all started after the shoulder surgery and pain block. We need help!!!! PLEASE!!!

    1. Ms. Trone,

      I’m not sure I can be of any help. If there was nerve damage, the common symptoms are weakness or numbness in that arm, and the EMG would show abnormal signals below the level of the shoulder block. LMK as you receive further information. You can email me at

  5. I received a popliteal nerve block prior to surgery. Very little warning that they would be doing it. Read form & had me sign it. I was sedated before the block & totally unaware during most of it. Elective surgery to remove large hardware from my ankle where I had a compound, traumatic break 3 years earlier, and still had numbness in my feet, ankle and leg.. This was 6 months ago. 36 hours for the block to wear off, then drop foot, pain & numbness ever since. Several Docs have given the opinion that damage will be permanent. Just finally was able to get a conductivity study, and MRI of thigh and low back. Results not back yet. I’m considering a lawsuit. Any advice on addt’l tests, timeline for medical care (should I be seen sooner for this, or by another specialist?) what can i, specifically, to improve my situation for the long-term?

    1. You can phone me at 650-465-5997 regarding your questions. Thanks.

  6. I am a retired professional ballet dancer. I danced professionally for 18 years. I recently had a double osteotomy, and midfoot fusion. After having an EMG nerve conduction test and MRI because of extreme nerve pain, tibial and fibular nerve damage was diagnosed. My neurologist is convinced it is due to the ultrasound guided nerve block administered behind my knee before surgery. I now have debilitating pain, and it is extremely hard to stand and teach ballet. I signed off on this nerve block 45 minutes before surgery without much information or education.

    1. Kathy,
      I’m sorry to hear of your injury, which has changed your life. More likely than not, your neurologist is correct, and the nerve block led to the nerve damage. Anesthesiologists are aware that permanent nerve damage can occur with regional nerve blocks, with an incidence of about one in 3000 cases, but very few anesthesiologists include this risk in their verbal informed consent discussion prior to the surgery. The written consent for the block, that you likely signed, says you could suffer nerve damage. Lawyers have told me that it’s difficult for them to win a case simply on the fact that an anesthesiologist didn’t give proper oral informed consent. University anesthesiologists who specialize in pain blocks have no interest in testifying against their colleagues. All this adds up to a flawed system which at times leaves patients permanently damaged, and with nowhere to turn. Personally I tell every patient of the one in 3000 risk, and if they’re willing to accept that, I proceed with performing a block. If they are worried about this risk, then I do not perform the block. It’s unfortunate but I believe most university training programs do not emphasize this approach, and the individual who is to perform the block will minimize any danger when they explain it preoperatively. Despite writing about this issue, I’ve not been able to effect any significant change in the system.

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