Acromioclavicular Joint

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Where is the ACJ and what does it do?

The Acromio-clavicular Joint (ACJ) is the lumpy bit you can feel on the top of your shoulder and is where the outside (lateral) end of the collarbone (clavicle) joins onto the acromion process which is part of the shoulder-blade (scapula). It only measures about 2 square centimetres in area and is the only bone-to-bone connection between the arm and the body. This means that a lot of force is transmitted across a small area and so it is prone to becoming inflammed and degenerate.

What is a type 5 injury?

This is where all the structures that hold the scapula to the clavicle (basically - the arm to the chest!) have been torn and the 'A' bit and the 'C' bit have become very widely seperated. Added to that the clavicle will have torn through its lining (periosteum) and through the muscles above it. We know that type 5 injuries should be reduced and stabilised surgically. In fact it may be that that the type 3's that don't recover were probably actually type 5's in the first place.

Types 4 and 6 are very rare and we don't need to discuss these.

 

So, do I need an operation?

The simple answer is, no, you don't. It is still the case that many type 3s will heal - though the type 5s won't.

However, in view of the fact that quite a lot of type 3s don't heal, it is now my practice to offer surgical reconstruction to all type 5's and type 3's.

The decision whether or not to have an operation depends on several factors such as what you, the patient, want to do; your activity level and your job. It is certainly easier to operate in the acute stage (the first 2 - 3 weeks) when the torn ligaments may join back together but even done 6 months or several years after the accident, the results are very good. So, if you feel you are making progress in the first couple of weeks after your injury, then you aren't missing the boat by deferring surgery and seeing how you get on because I can do just as good a job later on if that progress doesn't continue. 

 If I don't have the operation what is the treatment?

A couple of weeks in a sling for comfort then rehabilitation with the physios. You should be able to drive once out of the sling and, if you have a desk job and can get there, then you can go straight back to work. If you do a physical job then it could be 3 months before you are able to function properly. Return to sports follows the same pattern: swimming and running after a month, golf and tennis starting gently after 6 weeks and overhead gym work when it can manage it - maybe two months or longer.


And if I need the operation, what does that involve?

To stabilise the ACJ I have to bring the clavicle and acromion back into line with each other to eliminate the step and hold the two elements together. In the acute situation (within the first two to three weeks) the torn ligaments should bond back together again if they can be brought back into contact.

I do an operation called TIGHTROPE which is an arthroscopic (keyhole) procedure done through two 1 cm incisions (one at the back and one at the front of the shoulder) plus a 2 cm incision on the top of the shoulder. The basic principle of the operation is that I use a surgical ‘block and tackle’ to haul the shoulder-blade and arm back up into line with the clavicle and hold them together while the ligaments heal.

 

 

 

 

The ‘tightrope’ is passed through a drill-hole in the clavicle and a corresponding hole in the coracoid (part of the shoulder-blade) under arthroscopic control and then tightened up by pulling on the strings until the joint is back in line.

The wounds are closed with stitches that come out after 10 days and you will be in a sling for 4 weeks. You will be able to use your hand, wrist and elbow fairly normally but won’t be allowed to mobiise the shoulder during that period. Once out of the sling you will start physiotherapy to regain movement and rebuild strength and control. It takes about 3 months before you are back to normal and able to do full physical work.

If we miss that acute window then I need to do a different operation because the damaged ligaments won’t heal up even if the ends are brought into contact. In that situation I use an artificial ligament to hold the scapula and clavicle back together called the SURGILIG.

This procedure is done through a 6 - 8 cm incision across the top of the shoulder to gain access to the end of the collarbone and the coracoid process beneath it. The artificial strap is passed under the coracoid and looped over the collarbone which are pulled together and back into line before the strap is attached with a screw.

The post-operative regime is the same as for TIGHTROPE.

 

I have an arthritic ACJ. What is the treatment for that?

If you are getting pain in the shoulder and I determine it is from your ACJ, after an examination and x-rays and an MRI scan, then there are several treatment options. Usually by the time you get to me you will have tried rest, anti-inflammatories and physiotherapy so if they haven't worked we need to look at other possibilities.

What happens if I need a steroid injection?

The next step up is a steroid injection into the ACJ. I do this with you as an inpatient in hospital because the ACJ is a narrow gap at the best of times and much narrower when it is inflammed or arthritic and trying to get a needle into that gap in the clinic with you awake is very difficult. So, you come into hospital for a few hours, get taken down to the theatre anaesthetis room and have a short lasting general anaesthetic. This means you keep still and I can get the steroid exactly where I want it! You are ready to go home after a couple of hours. You should rest the shoulder for 48 hours just doing normal day-to-day stuff and then start doing those activities which had been causing pain. Hopefully that will be all you need to get back on the straight and narrow.

Tell me about the surgical option.

If the imaging shows that your ACJ is really badly arthritic, or your symptoms recur within a few moths of a successful injection, then the only way to rid you of your symptoms on a permanent basis is to surgically remove the outside 1 cm of the clavicle. This creates a gap between the bony surfaces so they won't rub against each other or dig down on the tendon as it passes below the joint.

The procedure is called an Arthroscopic ACJ Excision. It is done as a day-case under a combination of an inter-scalene block and a general anaesthetic (see inter-scalene blocks) and takes about 30 minutes to do. You will have 2 or maybe 3 incisions, each about a centimetre long, positined in the back, front and side of the shoulder. The surgery is done using long thin instruments inserted through these holes with the whole procedure being visualised via a digital TV camera onto a screen. Using a combination of shavers and softtissue evaporators, I will remove the tissue between the bone surfaces and then the end 1 cm of the clavicle.

Don't worry about losing this piece of bone! The gap created fills up with fibrous scar tissue and there is no loss of strength or stability in the shoulder.

This is a very common procedure in men over about 50 and in younger sports people such as rugby players and weight lifters.

How long does it take to get over it?

You will have a sling for a couple of days and then startto move the arm as normally as you can. As for a decompression (see tendonitis), it will take about 3 months to reach 80 or 90% or normal and maybe a bit longer to be able to sleep comfortably on that shoulder.


When can I return to work?

This entirely depends on what you do. If you have a desk job, are self-employed and you can get there, then you can go back virtually straight away. At the other extreme, if you are doing a heavy physical job such as brick-laying, then it may be 3 months before you can get back to work at full pace.


When can I return to sports?

It can be very frustrating being off games but a slow, structured return is essential. Many of my patients are golfers and, if that is you, then you can practice putting straight away. At 6 weeks you are permitted to go to the range but only to hit a dozen balls with a 9 iron. You will feel perfectly able to do more and you will be fine doing it at the time but when you wake up the next morning you will know that you have made a serious mistake! Then build up gently over the next 2 weeks working up through the bag and you shoud be playing 9 holes at 8 weeks and 18 at 10 weeks.

The same theory holds for tennis. Start off just spending 10 minutes hitting gentle forehands and backhands and build up from there through volleys before finally starting to hit serves after 8 to 10 weeks. Start with a spin serve before trying a flat, power serve.

Many people ask about going to the gym to do cardiovascular work and that can be a dangerous thing to do because, no matter how you try to relax, your shoulders will soon be pulled up under your ears! The best machine to use is a recumbent bike where you can reallty hang your arms by your side in a fully relaxed mode. After 4 to 6 weeks it is safe to run, bike and cross-train but avoid the rowing machine till 8 weeks.

And when you return to weights, get some proper advice from your physiotherapist or a personal trainer as there are many things you can do in the gym which you might think are doing good for your shoulders but are making them worse!


What are the complications?

I warn you about two potential problems. There is a theoretical risk of infection but I have never seen this in a keyhole operation of the shoulder in 8 years and many hundreds of operations. There is about a 1:100 risk of developing a post-operative frozen shoulder which is where the shoulder stiffens up in the weeks after surgery. Although this is a very annoying complication it can be fairly easily delat with. (see frozen shoulder)


What are the results of an AACJE?

The statistics for recovering from this operation are these: by three months 8 out of 10 people are 80% better. I think we actually have 9 out of 10 at 90%. That means virtually pain free and doing most of your activities and sports but with some discomfort and a few limitations. It probably takes another 3 months to reach 100% and 100% is the result I expect. I will ask you to fill in a score sheet before your operation and again at 3 months after it to audit my performance and outcomes.