Shoulder Problems in General Practice
The purpose of today’s talk is to discuss some of the more common shoulder conditions which are likely to be encountered in General Practice
So the first thing we need to decide is whether the problem with which the patient is presenting is a genuine shoulder issue or is it due to another structure.
Features which may suggest that the shoulder isn’t implicated include pain in the neck, pain in the upper back, pain involving the whole upper limb, pain radiating along the collarbone or into the anterior chest wall or if paraesthesiae are a prominent feature.
So what sort of features do you suggest that the pain is coming from the shoulder. Well, pain felt at the lateral border of the acromion or into the deltoid region is very characteristic of genuine shoulder pain. This pain is often worse when lying on the shoulder at night, when reaching up or out, or when putting the hand behind the back.
So I’d just like to discuss a few rules of thumb which may make the diagnosis of shoulder issues a little easier.
Firstly I think it's useful to consider that certain shoulder conditions are more common within certain age groups. For example, instability often in the younger age group these are often contact sportspeople such as Rugby players. Rotator cuff disease is essentially a disease of middle age most commonly. AC joint problems affect people with a broader age span. Frozen shoulder is again most common in the middle age group, particularly affecting women. Arthritis, not surprisingly, is a disease usually affecting the older age-group. Rotator cuff arthropathy is a particular type of arthritis affecting the older age group which arises as a result of chronic tearing of the rotator cuff.
I'd like to discuss some of these common conditions in more detail now, firstly instability.
Instability is actually, for the most part, fairly easy to diagnose. In general the patient will usually report a history of a significant injury and may well have attended Accident and Emergency following an incident. There are more subtle indicators of mild instability but these are beyond the scope of today's talk.
So that’s instability
The next thing we are going to consider is acromio-clavicular joint pain. The pain arising from AC joint issues is a little unusual in that it is felt at the AC joint itself, rather than the usual deltoid pattern pain, and may also radiate into the upper trapezius on the ipsilateral side. Patients tend to localise AC pain quite well and often feel it with overhead activities. There are some special tests for diagnosing AC pain which you can see on the relevant presentation.
So we’ve dealt with AC pain and Instability. The next thing we need to decide is whether the patient is suffering from a subacromial (or rotator cuff) problem or is it a glenohumeral joint issue. The reason we do this is because the other common conditions can be grouped into one or other of these categories.
How then do we work out into which of these two groups our patient’s problem falls?
Well, glenohumeral problems usually present with genuine restriction in range of movement with end range pain such as the patient on our left with the deficit of external rotation evident here.
Patients with rotator cuff problems there is generally discomfort lifting the arm up from the side when approaching so-called painful arch position dear, which is the mid zone between the arm being by the side and the arm being overhead. The pain often eases as the arm is taken above the top of the painful arc zone. There is often a hitching of the shoulder to try to reduce pain as the painful arc is approached and you can see this in the photograph of the gentleman on our right.
So there aren’t many conditions which result in loss of external rotation. These are basically frozen shoulder and arthritis. The other two rarer things, which are a mal-united proximal humeral fracture and a missed posterior dislocation will be apparent because of the history of injury, so it’s really the first two you need to think about. As such, loss of external rotation is very useful clinical sign.
So how do we distinguish between frozen shoulder and shoulder joint arthritis?
With arthritis there will obviously be loss of external rotation but unlike with frozen shoulder, there will be crepitus ie grating and grinding with movement and if an x-ray is taken this will be abnormal. With frozen shoulder, of course there is loss of external rotation but with no crepitus, often significant end range pain and a normal X-ray.
On the subject of x-rays it is important to order the correct series. This is probably the most useful of these.
The commonest error in this regard is to order and AP of the shoulder as opposed to a true AP of the gleno-humeral joint. The view on the left is an AP of the shoulder in which the joint line is not clearly seen. In order to assess arthritis in particular, the view on the right is required showing a view straight through the joint line. There’s an example in the photograph below.
So we have ruled out instability, AC joint pain, frozen shoulder and arthritis leaving us just rotator cuff problems to consider.
We can think of rotator cuff problems as a spectrum. The issues start with impingement and overtime the cuff becomes degenerate and eventually tears may occur. About 5% of people with large chronic tears will go onto develop a particular type of arthritis known as rotator cuff arthropathy. The typical patient with rotator cuff problems as already mentioned will have pain felt in the deltoid region particularly when lifting the arm up from the side. A patient who has developed a significant tear may struggle to lift the arm up at all.
I would like to move on to talk a little about local anaesthetic and steroid injections at this point as they are useful both as diagnostic and therapeutic tools.
The three main areas which you may consider injecting in general practice are into the glena-humeral joint, into the sub acromial space and into the AC joint.
Firstly, glenohumeral joint injections will be given if the suspected diagnosis is either frozen shoulder or arthritis of the ball and socket joint. However pain arising from Long head of biceps pathology and also undersurface partial tears of the rotator cuff (known as PASTA lesions) may also improve symptomatically with a glenohumeral injection.
Subacromial injections are more straightforward in that these are given when the suspected diagnosis is bursitis or a problem with the underlying rotator cuff.
In terms of the entry point of the injection I prefer to give both subacromial and glenohumeral injections via a posterior approach. Subacromial injections are given 1 to 2 cm inferior and medial to the postero-lateral corner of the acromion where you see the thumb. Glenohumeral injections are given slightly more medial to this in the so-called soft spot. Subacromial injections can also be given via a lateral route as shown by the position of the cross.
For glenohumeral injections you need to aim towards the coracoid whereas for the posterior subacromial approach you aim towards the anterolateral corner of the acromion.
AC joint injections are often a little bit more tricky as you will often be injecting into an arthritic joint where the joint space is diminished. I usually do these from the front as the joint space is a little wider here. The volume of joint is quite small so if you manage to inject more than about 1.5 mls of fluid, the chances are the needle tip is not correctly placed within the confines of the joint capsule. In terms of locating the joint, it's not always that easy. One tip which may help is to feel the soft spot where the spine of the scapula meets the back of the clavicle and the AC joint will be located in front of this spot.
I tend to use a mixture of either 40mg of Depomedrone or Triamcinolone with 5mls of 2% Lidocaine (or 1 ml for the ACJ)
It is very useful to note the site, also the immediate and longer term response to the injection in any subsequent referral letter. The ideal information would include both the level and duration of any improvement.
I would like to finish up by mentioning a few instances where the patient may benefit from an early referral. Not surprisingly if there any red flag signs suggesting either infection or tumour, early referral is indicated. Instability in the younger patient also warrants early referral as we are more aggressive in treating this particularly in the younger contact sporting group. We know that an injection given for frozen shoulder is more likely to be effective early on in the disease process, therefore if it is not possible to inject such a patient at the practice, then an early referral is beneficial.Patients with potential rotator cuff tears, particularly those with a history of trauma are also best referred early.
Thank you very much for you attention.
If you have any questions or would like to suggest any other areas related to the shoulder which would be of interest for further presentations then please do not hesitate to contact me.