Unraveling the Complex World of Shoulder Injuries: Insights from an Orthopaedic Surgeon

Join me, Dr  Gavin Nimon (Orthopaedic Surgeon), as I unlock the complexities of shoulder injuries for you, delving straight into the heart of one of the most intricate joints in the human body. We'll dissect everything from dislocations to tendon tears, bringing clarity to the often convoluted path to diagnosis and treatment. As an orthopaedic surgeon and senior lecturer, I'll provide you with invaluable insights that merge practical medicine with academic expertise, offering strategies that cater to both seasoned professionals and the curious minds of medical students.

Shoulder stability is a dance of anatomy and injury, where one misstep can lead to a cascade of problems. We examine the labrum's crucial role and how injuries like the notorious Bankart lesion can disrupt your groove. I explain why the debate between immobilization and early mobilization is more than just academic banter. 

In our final chapter, we pull back the curtain on the recovery journeys following shoulder dislocations. Exploring the genetic hand we're dealt and the ligamentous laxity that plagues some patients, we chart a course through the rocky waters of rehabilitation. 

Whether your interest lies in the nuances of AC joint injuries or the surgical reconstructions for chronic instability, this episode is a treasure trove of medical knowledge. And remember, while we're here to guide you through the maze of medical information, always consult a specialist for your unique health concerns.

Aussie Med Ed is sponsored by OPC Health, an Australian supplier of prosthetics, orthotics, clinic equipment, compression garments, and more. Rehabilitation devices for doctors, physiotherapists, orthotists, podiatrists, and hand therapists. If you'd like to know what OPC Health offers.

Visit opchealth. com. au and view their range online.

Transcript

Speaker 1: 0:22

G'day and welcome to the Aussie Med Ed, the Australian Medical Education Broadcast, where we get to interview specialists in a variety of medical areas, asking their opinion on their certain conditions and obtaining their insight into how they diagnose and treat that condition. In these COVID times, it's a way of replacing the relaxed discussion around the hospital by allowing the listener to put forward questions to be answered and addressed on their behalf. I hope you enjoy the whole program and welcome once again to Aussie Med Ed. And on this episode of Aussie Med Ed, I've been actually asked to talk about shoulder injuries. This is quite a common scenario and more common now that window season started in Australia and Australian rules football has returned to playing Constantly. Given it's my area of expertise, I've been asked to talk about it from an orthopaedic surgeon's perspective. Hopefully you'll find this little monologue useful, but please don't hesitate to email me for any other suggestions you might want to hear about and other topics of interest. I'm Gavin Nyman, an orthopaedic surgeon based in Adelaide and also a senior lecturer at the University of Adelaide, involved in orthopaedic musculoskeletal teaching. Not only would this information be useful for the general practitioner seeing a patient on a regular basis, but also for the medical student, revising for their exams or preparing for their OSCE examination.

Speaker 1: 1:28

I hope you enjoy the podcast series and, if so, please feel free to subscribe, give us a like or review or tell your friends about it. We look forward to having you listen to our podcast series and we hope you find it enjoyable. I'd like to begin this podcast by acknowledging the traditional custodians of the land on which this podcast has been produced and pay my respects to the elders, both past and present. So today I've been asked to talk about shoulder injuries and particular shoulder dislocations. I would like to thank my medical students who nominated this topic and, given it's my area of expertise, I've decided to give a small monologue. I hope you find this useful in a pragmatic approach to the treatment of such injuries.

Speaker 1: 2:04

I think I'll just start by saying that my first approach to shoulder injuries is the same as any other joint in the body. We like to try and divide it up into different classifications or different divisions. In the way I think about it, I like to think about things in groups of threes. What I mean by that is, if we divide an injury or a problem with a shoulder, we can think of it as being either elective, traumatic or a combination of the two, three divisions. If we think of the things that occur in the shoulder traumatic injuries we think of fractures, dislocations, maybe tendon tears and occasionally infections which may present as a traumatic presentation. These are the things that might present to a casualty presentation.

Speaker 1: 2:46

Of course, any assessment of a patient starts off by taking a full history and determining more about what occurred. Was it a simple bump while playing football or landing on a side of the arm so that it could strain the AC joint? Was there a knock to the neck which could lead to referred pain into the shoulder, or was there actually a tackle or something the arm held into abducted extreme rotator position with a definite sensation of the shoulder? Or was there actually a tackle or something the arm held into abducted extreme rotated position, with a definite sensation of the shoulder popping out a joint that could make you think of a dislocation? All these things can be factors in presentations that will help you to form a diagnosis. Following on from that, the examination is also extremely important, noting what the arm looks like when they present, ie does it look deformed and is it being held in the internally rotated position that makes you think of a dislocated shoulder, which is usually fairly obvious and the patient can feel like the shoulder's out of joint. Is it actually just more tender at the AC joint and it's more swollen on that side? Or is it a deformity of the bone? Or is the clavicle itself irregular and there's a large lump along the shaft of the clavicle, making you think of a clavicle fracture? If the history and examination is fairly insidious and if the patient looks unwell, you've always got to consider that the patient might be presenting recalling a traumatic episode, but maybe a first presentation of an infection of the glenohumeral joint or the soft tissues Less common but something worth considering. And of course, in an older patient an acute traumatic episode can lead to an acute disruption of the tendon and I've also seen this following motorbike injuries as well. Certainly an older person with a dislocated shoulder can lead on to an acute rupture of the rotator cuff, but this is less common.

Speaker 1: 4:18

When we come to assess the patient, obviously the history has been important, but also knowing past history is extremely important. Have they had other dislocations in other joints which would make you think of recurrent instability? Has there been a family history of it? And in my experience, patients who dislocate their shoulders often have had some other sort of soft tissue injury or some signs of laxity, such as they may have recurrent sprains in their ankle, they may have ruptured their cruciate ligament or they may have actually dislocated their other shoulder cruciate ligament or they may have actually dislocated their other shoulder. So these are vitally important information in the history.

Speaker 1: 4:48

The most patients that we would see are younger patient playing sport. They've actually had a fall whilst playing football or they've been knocked on the ground or they've come off a push bike, and these are very common presentations and they may present with an obvious deformity or dislocated shoulder which had need to be reduced in casualty, or it could present with a lump at the lateral end of the AC joint or clavicle, thinking of an AC joint subluxation or dislocation. Usually they're most tender at the localized site, ie they tend to at the AC joint or the shoulder itself, or they can't move the shoulder and the first investigation of choice is an x-ray which shows that the pathology straight off. So shoulder dislocations are very common scenario and certainly high profile and people ask why does it occur so commonly? Well, I think it occurs in a group of people that are more prone to it. These patients tend to commonly have a family history of dislocations, or they may have injured their knee previously, having ruptured a cruciate, or may have sprained an ankle in the past, and as such, these patients are more prone to getting dislocations. Therefore, there are some patients who more likely dislocate, and the ones who are extremely lax are probably even greater risk of re-dyslocation despite surgery. Why are shoulder dislocations generally fairly common too? It's not just relating to the actual hormones or the ligaments themselves or the genetics of the collagen fibres. Also, you just relating to the actual hormones or the ligaments themselves or the genetics of the collagen fibers, but also you've got to look at the actual anatomy of the shoulder.

Speaker 1: 6:11

The humeral head is four times larger than the glenoid socket, and I like to think of the glenoid as being a fairly shallow socket which is fairly flat. You think of it like a small saucer. If you try and balance a soccer ball onto a small saucer, it doesn't seem to sit there very well. The way the body produces a more congruent socket for the shoulder, it actually increases the size of the saucer or the glenoid by putting soft tissue around the outside of it in the shape of a lip, which is almost like turning the saucer into a soup bowl by putting a lip on the edge of the saucer. A soft tissue lip on the edge of the saucer makes it into a soup bowl. By putting a lip on the edge of the saucer, a soft tissue lip on the edge of the saucer makes it into a soup bowl. It's just like the glenoid has a soft tissue labrum around the edge which makes it into a socket for the humeral head.

Speaker 1: 6:55

This labrum or soft tissue is malleable or stretchy and can actually accommodate movements of the shoulder in many directions. But after an acute traumatic episode it can either tear or it can pull away from the glenoid with a fragment of bone with it. What we call a soft tissue tear of the labrum is called a Bankart lesion, whilst when bone pulls away with it as well, that's known as a bony Bankart lesion. Following a first-time dislocation, obviously the shoulder needs to be reduced. The treatment is an acute reduction manoeuvre and there's multiple different methods of reducing it, varying from the Hippocratic, where it's purely inline traction, to the Cocker method, which involves traction, internal and external rotation and other variations of these.

Speaker 1: 7:38

Now, once a first dislocation occurs, that soft tissue may not heal back to the correct position and in fact often doesn't, despite people thinking that a use of a sling might be required in the first dislocation. The sling will not hold the shoulder in the correct position or allow the labrum to heal back appropriately. On occasions the labrum may sit back well and heal up fine or the patient may go on to get stiffness anyway and not have recurrent instability. But some patients will get recurrent instability because the labrum doesn't either heal back to the glenoid edge or it actually heals, but more medialized. It's a bit like taking the soup bowl with a soft tissue rim to it, breaking the rim off and then trying to glue it back, but gluing it back in the wrong position and the soccer ball wants to fall out of the soup bowl. Therefore the the soft tissue anatomy which pulls away from the bony anatomy predisposes to recurrent instability in a lot of patients If the large fragment of bone comes away with the labrum or known as a large bony bankart lesion, and often we talk about a figure about 20% the width of the glenoid.

Speaker 1: 8:42

If a large bit of bone pulls away, then this makes it even more unstable because the size of the glenoid. If a large bit of bone pulls away, then this makes it even more unstable because the size of the glenoid is now smaller and therefore increases the chance of re-dissecation. Consequently, after a first dissecation, there's a large number of patients who are going to get re-dissecations or secondary instability and therefore in some patients it may be advisable to actually, after the first dislocation, to advocate for either repairing the labrum or at least being a bit more cautious in their rehab. Consequently, shoulder dislocations are relatively common because of the anatomy and the predisposition to develop dislocations, because of the small size of the glenoid and the soft tissue labrum, also relating to a genetic predisposition, in some people with ligament laxity and this has been made worse over recent years with the actual extreme force put through the bodies and the demands of the sporting athlete in many of the sports that are undertaken.

Speaker 1: 9:41

Shoulder dislocations, of course, can be classified in several ways. They can be the first-time dislocation or recurrent dislocation. They can be unidirectional, ie it goes out either the front, anteriorly, posteriorly or inferiorly, or they can be multidirectional instability and it's also going to be assessed by the patient's genetic predisposition for it, ie do they have lax ligaments? In general, most dislocations are unilateral, ie anterior dislocations occurring after a first episode and then leading to recurrent instability. Some patients, however, have multidirectional dislocations. Likewise, the examination can be useful too, such as looking at hyperextensibility of the elbow, the wrists, the fingers and the knees, and various forms of classification of ligament laxity, such as the wind davies signs or other other classification systems, can be used to decide whether it is generalized ligament laxity. But this should be taken into account. It's probably one of the most useful assessment tools I have to determining whether there is a likely chance of recurrent instability.

Speaker 1: 10:46

There used to be some talk about putting them in a sling to try and help the shoulder stabilise. However, it's been shown that the sling the standard sling doesn't hold the shoulder in the correct position for the labrum to heal in the correct position. Really, if you are going to put them in a sling, you've got to put them in an abduction sling with the arm in the neutral alignment, ie pointing straight ahead, with the arm away from the body. While there are specific slings for this, and we do use them post-operatively on occasions, they don't really hold the shoulder as well as we'd like, because the moment you get undressed or take them off to have a shower, the shoulder moves back into the incorrect position. Therefore, nowadays, after one dislocation, the standard treatment would be to place the patient in a sling for comfort and as soon as the sling sorry, as soon as the pain settles, then the sling can be removed.

Speaker 1: 11:34

Mobilization can be recommenced so as to strengthen the musculature around the shoulder and prevent atrophy. There have been studies that show in patients under the age of 35 who have a first-time dislocation, there's a large number of re-dislocations, quoting even up to as high as 80%. Consequently, in the high sporting endeavouring patients, it may be suitable to consider an arthroscopic stabilisation or repair of the labrum initially. However, most patients might be treated with a sling for a period of time and hope that the shoulder doesn't re-dissolvate. In these patients we organise physiotherapy to strengthen the musculature around the shoulder, the subcapillaris, supraspinatus, infraspinatus, as well as the deltoid, with a slow return back to normal activities over a period of time.

Speaker 1: 12:23

If there's been a bony bankart lesion and the labrum is pulled away with a large amount of bone from the front of the glenoid, then this is a different scenario and it makes the patient or the shoulder more unstable. In this scenario, it might be an argument for considering an early stabilisation or repair of this bony fragment or, on occasions, this may be accepted if it's less than 20%, but if it does go on to develop instability, then it may mean a different type of surgical procedure is required. Of course, there are different types of scoring systems to help determine the prognosis for a shoulder instability, and one particular scoring system is known as the ISA score, which looks at the age of the patient at the time of the injury ie less than 20 gives them a higher score than greater than 20, the degree of sporting competition ie is it competitive or just recreational. The type of sport is it contact or forced overhead. Whether the patient has pre-existing shoulder hyperlaxity and whether there's also a deformity on the humeral head at the time of the x-rays taken, as well as a deformity of the glenoid. Now, when the shoulder dislocates it actually can it pumps out the front of the shoulder over the edge of the glenoid and make a dent in the back of the humeral head. This dent is known as a Hill-Sachs lesion, spelled H-I-L-L, hyphen S-A-C-H, apostrophe S a Hill-Sachs les lesion. And this is actually a dent on the humeral head which, when the shoulder rolls into a certain position, can engage on the edge of the front of the glenoid and lever itself out. Most hill sax lesions are small or shallow and don't have any major impact. But a large hill sax lesion, combined with also some deficiency in the glenoid, can lead to quite severe shoulder instability. So, by taking into account the age of the patient, the level of sporting prowess, the actual degree of sport they're playing or the type of sport, as well as the bony anatomy that's been damaged at the time of the injury, can determine whether the shoulder is going to be unstable or be stable. And for the most unstable ones, then the ISA score would assess this patient as requiring surgery. So what sort of surgery is performed? Well, there's various types that can be undertaken, but most come down to either an anatomical repair or a reconstruction.

Speaker 1: 14:36

Now, the anatomical repair is designed to try and repair the labrum back to the edge of the glenoid, as well as tightening up part of the ligaments around the capsule. This can be done either arthroscopically or through an open approach, usually through a cut on the front of the shoulder. Usually, this involves roughening up the edge of the glenoid and tying down the labrum to that, either using sutures or usually sutures with anchor attached to small fragments of plastic or metal, known as anchors, to tie the labrum down to the edge of it. Some of these anchors are bioabsorbable and others are dissolved with time. Others remain permanently in. This will help bring the labrum back to the edge of the glenoid and also tighten up the capsule around it. This is known as an anatomical repair and is performed for either anterior, but can be done for anterior, posterior and inferior instability.

Speaker 1: 15:25

If there's a large amount of bone missing, however, then the bone needs to be reconstructed in some way, and also if the patient has had an anatomical repair previously and they've gone on to re-deslocate, then a salvage procedure needs to be undertaken, and the most common one of these nowadays is known as a Latigey procedure, also known as a Latigey bristow, and this is where a piece of bone is attached to the front of the glenoid, and the most common way of doing this is taking the anterior half of the coracoid process, which is right next to the shoulder. It's actually an extension of the scapula, and attached to that piece of bone is the short head of biceps and the coracobrachialis musculature. Now this bit of bone, along with those tendons, are transferred to the front of the glenoid and secured with one or two screws. This increases the size of the glenoid by increasing the width from front to back, as well as reconstructs or repairs or replaces the bone that's missing, and also allows for those tendons attached to the short head of biceps and the coracobrachialis to act as a sling so that, when the arm is in the abducted and externally rotated position, holds the humerus back into position. And it is this latter aspect which probably helps to the stability of the shoulder. Pictures of these can be shown in many textbooks and you can have a look at those, but, needless to say, this is more commonly done nowadays than it was several years ago.

Speaker 1: 16:55

Unfortunately, despite our best efforts, however, shoulders can go on to re-dissocate and there is certainly many examples of this often seen in the media. And there is certainly many examples of this often seen in the media. This relates to the fact that the actual patient's genetics are still abnormal, in that often the patients who dislocate have shoulder instability or ligament laxity, as we talked about prior. Whenever an operation is undertaken, the patient will still need a period of time in a sling and immobilising their shoulder and then coming out to slowly regain range of motion, often avoiding the position of dislocation for a period of time and then slowly strengthening it with a slow return back to full activities, depending on what the surgeon is happy for the patient to do Now.

Speaker 1: 17:40

The other dislocation that occurs around the shoulder which is quite common, is the dislocation of the acromioclavicular joint. This is also a very common scenario, often when the patient or sportsman is driven into the ground by a tackle and the tip of their shoulder hits the ground in an axial direction, so consequently, the actual shoulder is driven down with the patient on their side. In this scenario, the actual AC joint or the end of the clavicle hitting the edge of the chromium takes an impact and this can lead to a sprain or soft tissue swelling around the area, or it can lead to actual disruption of the ligament stabilising this joint. The stabilising structures for the acromioclavicular joint are predominantly the ligaments from the coracoid to the undersurface of the clavicle, known as coracoclavicular ligaments. After a significant strain or force is transmitted through this, these can be disrupted, leading to either stretching or complete breakage of one or both of the ligaments and therefore the actual joint becomes unstable. This may present with pain at the AC joint and a lump at the area, and what that lump is perceived to be is the clavicle setting up out of joint. What really is happening is the coracoclavicular ligaments are disrupted and the whole of the shoulder is falling off the clavicle. Normally the coracoclavicular ligaments hold the shoulder, the scapula, the glenohumeral joint, hold the arm up to the clavicle and when they're disrupted, gravity itself lets the scapula fall away.

Speaker 1: 19:17

The degree of displacement can be graded and there's many different grading systems, but the most common one used is the Rockwood classification, which relies on type 1 being a sprain with no disruption to the x-rays, type 2 being slight displacement, type 3 being up to 100% displacement, type 5 being over 100%, while type 4s and 6s are in different directions and they're quite rare. So normally I try and think of them as a sprain totally undisplaced, slightly displaced, significantly displaced or very significantly displaced. Types 3 and type 5 are the more common ones that present to an orthopaedic surgeon and there's different evidence of how they're treated. Most people consider type 3 can be treated with or without surgery, whilst type 5 may be recommended to have surgery. The main issues that can arise from these dislocated AC joints are both the cosmesis it looks abnormal but more importantly, it actually puts stress on the muscles around the shoulder, leading to discomfort. A lot of patients will be able to cope quite well with a dislocated AC joint and many patients may decide not to go for surgery. Usually, after initial injury, the patient is treated with ice and rest and placed in a sling.

Speaker 1: 20:31

Once the swelling settles down and x-rays are performed, one can assess how far displaced the AC joint is. If it's only moderately displaced or minorly displaced ie it's a sprain or it's less than 25% or certainly less than 100% displaced, then physiotherapy may be started and the patient might find they do quite well. If, however, it's getting up to 100% or more, then surgery may be offered, depending on the patient's situation. This surgery, however, is often best undertaken in the first few weeks following injury to allow the coracoclavicular ligaments to scar up and heal. If left longer, then it needs to be considered a reconstruction-type procedure.

Speaker 1: 21:09

The initial procedures, if done in the first few weeks, involves tying the clavicle down to the coracoids so the ligaments between the two bones can scar up and heal, and there's various ways of doing that Often involve passing of a suture, either percutaneously or through a small cut on the front of the shoulder. Sometimes the past screws have been used and there are other devices that can be incorporated. Recovery depends on how well the patient heals, and certainly the older the patient or the poorer the health, the less chance there is for the ligament to heal, and also depends on if there are other factors too, such as smoking, which delays the healing of the ligaments to the bone. If there are other factors too, such as smoking, which delays the healing of the ligaments to the bone, if the patient isn't treated in the acute stages but does go on to develop problems later, then there is always a procedure available, such as a reconstruction-type procedure. This can involve repairing the ligaments, primarily tying the clavicle down to the coracoid, but also using a substitute or reconstruction to help reconstruct the ligaments between the two bones. This may involve transferring another ligament nearby to the undersurface of the clavicle or even taking a tendon from somewhere else in the body to use. Either way, whether it be an acute repair or a delayed repair, there is a risk of failure because the ligaments may not heal and then the tendons can pull away from the bone. Most AC joints, however, don't involve a significant displacement and can be treated without surgery and require just ice and physiotherapy. And if surgery is required for the more displaced one down the track, most patients heal very well. The chance of re-injury is significantly less.

Speaker 1: 22:44

There are other dislocations that occur around the shoulder. The third joint in the shoulder is the sternoclepipedal joint. This can dislocate either anteriorly or posteriorly. The problem with this joint is that it's usually fairly stable but once dislocated, reduction often remains unstable. An anterior dislocation will often scar up and leave to a lump, but often doesn't cause any major issues, while posterior dislocation and acute setting can put pressure on the trachea or the vasculature around the trachea and this can be quite serious and should be reduced immediately. Luckily, these injuries are fairly rare and for the medical student just need to be aware of.

Speaker 1: 23:22

I think this is a small summary of the injuries that can occur around the shoulder and the things to look up for as a for a medical student. Obviously you can go into a lot more detail and textbooks will give you a lot more information about this, but this gives a little pragmatic approach to how I approach most shoulder dislocations, either glenohumeral joint or the AC joint. I hope that explains things a little bit more detail. I hope in the meantime please stay safe and we look forward to our next episode of Aussie MedEd. Thank you for listening.

Speaker 1: 23:53

The information provided to you today is designed to complement the information provided to you in your local region and should supplement your readings and teachings in that area.

Speaker 1: 24:02

Please don't take it as the only way of treating this condition or assessing a condition, but really as one of various ways of assessing these conditions. Please also be aware that the information provided today is really just general medical advice and isn't designed to actually be a source of medical information regarding your particular condition. Remember to consult your specialist or medical practitioner if you have concerns about a condition raised in this podcast, or specialist or medical practitioner if you have concerns about a condition raised in this podcast. Thanks once again for listening to our podcast, aussie Med Ed or the Australian Medical Education Podcast. We really enjoy hosting this podcast. I hope you find it useful to hear a pragmatic approach to everyday conditions. If you have any questions or information you want to ask about us or you'd like to put a suggestion for a topic, please don't hesitate to email us at gavin-edcomau. Once again, I hope you've enjoyed listening to it and we look forward to hosting it next fortnight when we introduce a new topic. Thank you.