Shoulder Surgery Complications Caused by Acromioplasty

By /

Shoulder decompression surgery, otherwise known as an acromioplasty, involves removing part the acromioclavicular (AC) joint structures and ligaments from the shoulder and is usually done in conjunction with a rotator cuff repair. The rational is that the bones and ligaments are impinging (pressing) upon the rotator cuff, so the surgeon performs an acromioplasty (cutting the ligaments and shaving the bones) to free up the space. On the surface it sounds logical; however, when you cut some of the major stabilizing ligaments of the shoulder, there are deeper issues beneath the surface you may have to contend with, such as shoulder instability, arthritis, and additional rotator cuff injuries.

Today, we’re going to take a live look at a moving X-ray of a patient’s unstable shoulder following an aggressive AC joint resection (the big brother of acromioplasty) and talk about the shoulder surgery complications that can result from an acromioplasty.

Where and What Is the AC Joint?

For most of us, it should be easy to locate the AC joint. Place your fingers on your collarbone (the clavicle) at the base of your neck and follow it toward your shoulder. The clavicle is straight and smooth until you come to a “speed bump” type of prominence as you reach the shoulder, almost as if it’s a warning to slow down before you reach the top curve of the shoulder. This prominence is the AC joint, and if you continue to follow the path with your fingers, just beyond the joint is the acromion bone of the shoulder—hence the name acromioclavicular joint as it bridges the clavicle (collar bone) to the acromion (front projection of the shoulder blade).

When the AC joint develops arthritis or is misshapen, it can place pressure on the rotator cuff. When this doesn’t get better with physical therapy, often surgical decompression (acromioplasty) is performed. Acromioplasty involves cutting off the bones pressing on the rotator cuff and removing important stabilizing ligaments that live there. So besides the obvious—it’s rarely a good idea to cut out something we were intended to have (as I’ve said before, the body has no spare parts)—why is acromioplasty often a bad idea?

Let’s start with the research.

Request a Regenexx Appointment

What Does the Research Show Regarding Acromioplasty?

Not surprisingly, the research does not shine a positive light on acromioplasty. This past January, I shared a large randomized controlled trial showing that there is no advantage to adding an acromioplasty to a rotator cuff repair. Specifically, the study stated that findings were “consistent with previous research reports in which there was no difference in functional and quality-of-life indices for patients who had rotator cuff repair with or without acromioplasty.” In addition, the acromioplasty creates longer and more difficult recovery times for patients.

Taking this a step further, in 2014 I shared a study showing that not only rotator cuff repair with acromioplasty but also rotator cuff repair alone for rotator cuff tears due to wear and tear couldn’t outperform physical therapy.

I reported back in February that rotator cuff repair with acromioplasty is the most common shoulder procedure in the U.S., yet the study I highlighted showed that it was actually accomplishing the opposite of what surgeons thought. The purpose of the procedure is to reduce the forces on the injured rotator cuff, but the procedure actually increased them. The authors concluded that acromioplasty “increase(s) the rotator cuff force required to maintain normal glenohumeral biomechanics by 25% to 30%.” So in a bizarre twist of concept, acromioplasty doesn’t reduce forces on the shoulder rotator cuff repair—it actually makes them worse!

Let’s finish by looking at what really happens after this surgery.

A Moving X-ray of Shoulder Surgery Complications Caused by Removing the AC Joint

First, watch the short video at the top of this post to view the live, moving X-ray of one patient’s shoulder after undergoing an AC joint resection. If a picture is worth a thousand words, a moving picture is worth ten thousand. In the video, you will see the patient’s collar bone and the huge gap in the bone where the AC joint was lopped off by the surgeon. It’s that gap, you will see, that leads to these deeper problems and causes significant instability in the shoulder.

In the moving X-ray, we begin with the patient’s shoulder down and relaxed, the huge gap clearly visible. As we watch the patient’s shoulder move upward, the gap closes in. Remember, this gap is where the AC joint used to live before it was excised, where the ligaments kept the shoulder all nice and stable. This constant opening and closing of the gap means that the shoulder is grossly unstable and is beating up the shoulder with every movement. No wonder this poor guy’s shoulder pain got worse.

The upshot? As you can plainly see with you own eyes, the shoulder surgery complications created by removing the AC joint (the big brother of acromioplasty) create more problems than the surgery solves. In addition, the research doesn’t support that an acromioplasty benefits a rotator cuff repair, and, in fact, shows quite the opposite—that it makes the forces on the rotator cuff worse, not better—leading us to again ask an urgent question. Why in the world is this procedure still so commonly done? While there may be a few patients where it should be done, acromioplasty is just not a good idea in most cases. In addition, it’s a permanent bio mechanical change that can’t be undone, so once you head in this direction, nobody can give you a stable and normal shoulder back!

Join us for a free Regenexx Shoulder Webinar

This blog post provides general information to help the reader better understand regenerative medicine, musculoskeletal health, and related subjects. All content provided in this blog, website, or any linked materials, including text, graphics, images, patient profiles, outcomes, and information, are not intended and should not be considered or used as a substitute for medical advice, diagnosis, or treatment. Please always consult with a professional and certified healthcare provider to discuss if a treatment is right for you.

Get Blog Updates by Email

By submitting the form, you are agreeing that you read and consent to our Privacy Policy. We may also contact you via email, phone, and other electronic means to communicate information about our products and services. We do not sell, or share your information to third party vendors.

Leave a Reply

Your email address will not be published. Required fields are marked *

19 thoughts on “Shoulder Surgery Complications Caused by Acromioplasty

  1. Joseph Gerace

    How does Reverse Shoulder Surgery compare with Acrimoplasty and Stem Cell procedures?

    1. Regenexx Team Post author

      Acromioplasty is a Rotator Cuff Tear surgery in which the AC joint is surgically removed to release pressure on the Rotator Cuff, the result of which is major shoulder instability as shown in the video. A Reverse Shoulder Surgery is a total shoulder replacement done in cases where a large rotator cuff tear has resulted in a complex type of shoulder arthritis. The usual cup and ball are reversed meaning the metal ball is inserted into what had been the shoulder socket, and the cup is inserted into the humerus bone where the ball of the natural shoulder joint had been removed surgically. The purpose is that by reversing them the rotator cuff is not needed as much to operate the shoulder. Needless to say both of these options change the biomechanics of the shoulder irreversibly.
      We can’t comment on stem cell procedures in general as the variety of what’s being injected, technique, experience and training varies so greatly.
      Regenexx shoulder stem cell procedures treat the specific problems in your shoulder with precise image guided injections of your own stem cells in a 3 part patented procedure. The procedure is done without removing body parts or adding hardware, without creating surgical trauma in a joint already suffering from inadequate stem cells for repair, and without doing anything to negatively affect the biomechanics of the shoulder. Please see: and and

  2. Mark

    Do most Arthroscopic Subacromial Decompression surgeries remove the AC joint? I was under the impression that the point was to remove the bony outgrowths and increased the space to alleviate the inflammation. I mean, how else are the spurs and compression treated? Does shaving down the bones also compromise the surrounding ligaments?

    1. Regenexx Team Post author

      There are different degrees of decompression. At the least, just the spurs are removed, but that’s less common. Then the ligaments and bone can be cut. At the most the whole AC joint can be removed. We have at least two high level Randomized Controlled Trails that show that the procedures (in total most commonly known as acromioplasty) are ineffective. Why? It’s likely because the most commonly used variations of the surgery destabilize the joint – so you “fix” one problem (pressure on the rotator cuff) by creating a new one (instability in the AC joint and added forces on the rotator cuff tendons).

      1. Mark

        Thanks for responding. So, as I understand it, any form of decompression surgery, whether it’s removing the spurs, shaving to enlarge the space, or/and AC joint removal, will all destroy certain necessary ligaments and can possibly create destabilization of varying degrees, correct? Even the most “honest” ortho docs never told me this might result. From those shoulder surgery patients I have spoken to and read about, it seems that maybe 50% have a successful outcome post-op and are able to resume their prior activities, and the other 50% have chronic protracted issues.

        Other question: What specific diagnostic procedure (i.e. ultrasound, MRI, etc.) determines whether one has a retracted tear or not?

        1. Regenexx Team Post author

          Any cutting of the ligaments (which is very common) results in an unstable shoulder. Yes, the vast majority of orthopedic surgeons never discuss this risk, nor do they discuss that we have two high levels studies showing that an acromioplasty is not helpful to patients. All MRIs should show whether the tear is retracted and how much, but oftentimes radiology reports will leave that detail out.

          1. Mark

            I am 56 and have been an avid weight lifter since the age of 20. My shoulder issues originally began with impingement syndrome/tendinopathy in one shoulder three years ago. I was told I was a “candidate” for surgery, however via months of PT and avoiding direct shoulder training, the inflammation gradually went away and I was able to avoid surgery. Several month later, I began to experience the same pain in the opposite shoulder. I again scaled back my training and once again, applied PT exercises and looked into regenerative medicine. I then had a series of three ultrasound-guided PRP (mixed with HGH) injections done last October into the joint and tendon. At that time, I had a partial tear of the supraspinatus. The weeks of chronic inflammation gradually subsided and my strength increased. During my rehab downtime, I did PT and kept my resistance training to lighter weights and no direct shoulder work. However, in March, I had a followup MRI which showed the tendon had progressed to a full-thickness tear. The question I cannot answer is whether I interfered with the post-injection healing process by not giving myself enough time off all upper body resistance, thus causing the tear to progress – or – if the PRP therapy was a failure. This was unfortunate, as I was hoping I could use the PRP as a primer for predicting the success of going one step farther if need be – stem cells. The good news is that I have avoided surgical intervention up to this point. I am not giving up and still believe regenerative therapy is the way to go, otherwise, I wouldn’t be on here education myself and asking more questions . Any thoughts?

          2. Regenexx Team Post author

            Avoiding surgical intervention is a very good thing! In reference to the HGH, we tested it in our university style lab and were unimpressed. PRP’s effectiveness depends on whether it’s the right treatment for the problem, the type and quality of the PRP, whether it’s customized to the patient, and being able to inject the right spot. Given that all of those are unknowns in this case, there is no way to tell whether it was a failure of the PRP, or the training schedule. and A full thickness tear would likely require stem cells. To see if your specific situation would be a good Candidate for a Regenexx Stem Cell Procedure, please submit the Candidate Form:

  3. Lucy

    While the big brother version of an acromialplasty cut the clavicle, The little brother version procedure cut the acromion distal end. What ligament is cut ? I thought it only cuts the very tip of the actomion and is that also bad? How does this instability feel? I just had this procedure with rotator cuff repair, I thought I still have my ac joint but lost a portion of acromion. I think I also lost the coracoacromial ligament. I wonder what I should expect or what to do to try to salvage.

    1. Regenexx Team Post author


      Unfortunately, cutting the acromion cuts the origin of important AC ligaments and destabilizes the shoulder leading to AC joint arthritis and more rotator cuff problems.

      1. Lucy Li

        During the acromialplasty, bone is shaved to actually expose a raw surface, where I suppose stem cells live? Is it sort of activating local stem cells to the rescue? If the released coracoactomial ligament is still around (attached to the coracoid Undisturbed on the other end ) would it grow to attach back? So are the affected CC ligament footprint underneath the acromion ? What happens to the raw surface of the shaved acrimion ? I was hoping for the best that my body and the stem cells live inside my actimion can do some magic to help with this unfortunate event..( yes if fully informed I would not do the acromialplasty )

        In the unfortunate event things don’t grow back, how big a footprint does the Ac joint ligament gave on the acromion? I ask because I want to know how much cutting of the acromion is still safe to leave most of Ac joint ligament functional ( mainly the cc ligaments ). The CA ligament is only involving the scapula so not affecting the Ac stability? I do feel, however, that my CA ligament is reattaching on its own after the release, but is there a test to confirm this?

        1. Regenexx Team Post author

          Luci Li,
          After examining hundreds of these patients, these ligaments don’t usually grow back. The shoulder is left unstable.

          1. Lucy Li

            Dues thus 2018 paper by o levy carry any credibility ?


            If it dies grow back, dies the body have a way to lfoperlu tension it ?

            Can Regenexx help in the salavage of compromised CAL?

            Wgat happens to the birds that was also cut out? Maybe overlooked, but I think birds has an important role protecting the rotator cuff tendons against mechanical tuning and bumping. Can Regenexx grow birds back ?

          2. Regenexx Team Post author


            Your questions will require an exam. Let us know when you’re ready, and we’ll have our team get you scheduled.

  4. Rita

    I suffered a left shoulder dislocation on 4 July during a fall. Had successful reduction done. Had 1 physio session, due for another tomorrow (3 August) Had a scan done today (2 August). My shoulder doctor has now advised me to have arthroscopy, acromioplasty plus rotator cuff repair surgery on 10 August. Am really confused after reading up on acromioplasty. Do you feel it’s too soon to decide on surgery as I do. What do you advise. More physio. Please help.

    1. Chris Centeno Post author

      I would never let a surgeon perform an acromioplasty on my shoulder. We have treated many rotator cuff tears and unstable shoulders through a precise ultrasound-guided injection of high dose PRP or bone marrow stem cells. However, imaging and an exam would need to be performed to see if you are a candidate.

  5. Eli Rochford

    Hi Chris,

    I had a fall in March 2014 snowboarding in Whistler resulting in what was graded as a Grade 3 Shoulder separation (X-rays only). Returned home to Australia and healed up and got back to work and Tennis within 2 months with substantial but manageable pain. 5 years down the track and I am getting acute pain while playing tennis mostly serving and a 2to3 out of 10 dull ache most of the time. I have since got second and third opinions and both have graded as a high 4 or 5 (more posterior movement of the clavicle). One says shave the clavicle and repair the ac joint, other is of the same opinion as you with no evidence that there is any benefit (pain wise) from shaving the clavicle.

    My question is long term after not shaving the clavicle (playing tennis) will the clavicle tend to rub on bone causing the acute pain that I’m getting now or will the repair on the ac joint give enough stability that this will not happen. As the reason the first surgeon gave was shaving the clavicle with stop the acute pain and since I have no ligament joining the clavicle to the acromion there is little difference in taking some clavicle off?


    1. Regenexx Team

      Hi Eli,
      Based on published research and our own clinical findings, it’s not something we recommend. But, to advise in a particular case, we would need more information through the Candidacy process, and ultimately to examine you. Please see: and and To see if you would be a candidate to address the situation without surgery and the issues it causes, please submit the Candidate form here:

  6. Brenda bratron

    I agree this should not be done. I had this done during second rotorcuff surgery and it painful and now I have major instablitliy. Also have more tearing in rotor cuff

Is Regenexx Right For You?

Request a free Regenexx Info Packet


Learn about the #1 Stem Cell & Platelet Procedures for treating arthritis, common joint injuries & spine pain.

Join a Webinar


Get fresh updates and insights from Regenexx delivered straight to your inbox.

Subscribe to the Blog


9035 Wadsworth Pkwy #1000
Westminster, CO 80021


Copyright © Regenexx 2021. All rights reserved. | Privacy Policy

*DISCLAIMER: Like all medical procedures, Regenexx® Procedures have a success and failure rate. Patient reviews and testimonials on this site should not be interpreted as a statement on the effectiveness of our treatments for anyone else.

Providers listed on the Regenexx website are for informational purposes only and are not a recommendation from Regenexx for a specific provider or a guarantee of the outcome of any treatment you receive.