This article is not intended to be anything other than a guide for anyone who suffers from shoulder pain caused by tendinitis or tendinopathy of the supraspinatus tendon.
Although the title of this article names the supraspinatus tendon as the structure that is most affected in the shoulder, it is important to emphasize that the shoulder is a joint complex that performs many movements, so it is normal for there to be a global involvement of joint biomechanics, affecting more structures adjacent to the supraspinatus tendon (rotator cuff), as occurs in subacromial syndrome or impingement of the shoulder. We start at the beginning.
What is the supraspinatus muscle and what are its characteristics?
The supraspinatus muscle is part of the rotator cuff. It is located in the posterosuperior area of the back.
- Origin: This muscle originates from the supraspinatus fossa of the scapula (the bone we know as the “shoulder”).
- Insertion: It inserts on the greater tuberosity of the humerus (also called the greater tuberosity).
- Innervation: It is innervated by the subscapular nerve.
- Vascularization: It is irrigated by the sub-scapular artery.
- The function of this muscle is to stabilize the shoulder and start the abduction movement, it works in the first degrees (0-30°), after these degrees other muscles are in charge of the movement.
The supraspinatus muscle tendon has the characteristic that it passes under the acromion of the scapula. This makes it sensitive to a pinch (we will explain it later).
What is supraspinatus tendinitis or tendinopathy, subacromial syndrome or impingement?
The shoulder is one of the joints that develops the most tendinous injuries, above all because it requires mobility in all directions, as well as strength and stability to be able to carry out the activities in which it is involved. Therefore, it is not surprising that rotator cuff pathology and in particular supraspinatus tendinopathy is one of the most common pain syndromes in humans.
The term “tendinitis“, although very widespread, has recently been discarded by the medical-scientific community, since it has been proven that the tendon itself does not become inflamed, but the structures that surround it do, so it would be more correct call it tendinopathy.
Why does the supraspinatus break? Pathophysiological explanation of supraspinatus tendon injury.
Within shoulder tendon pathologies, supraspinatus tendinopathy is by far the most frequent. As we know, this tendon is particularly susceptible to developing injuries due to its anatomical disposition, since it is sandwiched in a space formed in its lower part by the humeral head and in its upper part by a vault formed by the floor of the acromion and the ligament. Coracoacromial that together make up a space called “subacromial space“. This tendon runs through said space inserting into the superior pole of the humeral tuberosity.
What is subacromial syndrome?
To understand exactly the causes and pathophysiology of this injury, one must understand what the subacromial space is. Look at the following image:
As you can see, the supraspinatus tendon is lodged between the head of the humerus (it inserts into the greater tubercle of the humerus) and the coracoacromial vault composed of the acromial tuberosity of the scapula and the acromioclavicular ligament. This space, for different reasons, is reduced and, as a consequence, increases the friction and wear that trigger supraspinatus tendon injuries that subsequently affect other adjacent structures such as the subacromial bursa; generating a painful clinical picture that affects not only the supraspinatus tendon and is called subacromial syndrome.
What is shoulder or supraspinatus tendonitis and what are its symptoms and causes?
In the following video we explain a little better how the shoulder complex is configured and understand graphically about the stages of involvement of subacromial syndrome:
What factors influence the appearance of shoulder tendon problems?
The etiology of this lesion is very varied and multifactorial. There is no specific cause that will determine the appearance of it, but it will be an achievement and group of factors that end up triggering the injury.
Biomechanical and postural factors
As we have mentioned, the main cause of this condition is the significant reduction of the subacromial space and therefore, the so-called joint impingement is generated where the supraspinatus is compromised, generating the signs and symptoms described above. But why does this narrowing of the subacromial space occur? This is where the physiotherapist must explore the posture and biomechanics of the scapula as well as the alterations in the scapulo-humeral rhythm to try to restore the correct function of the shoulder joint complex.
Age, osteoarthritis and previous joint degeneration
As in the vast majority of musculoskeletal disorders that we treat, aging, dehydration, loss of flexibility of tendon and joint tissues, as well as micro-trauma accumulated over time, increase the predisposition to tendon problems, without being in my opinion the determining factor, since as we will see, there are many other causes on which we can act as we will see later.
Genetic or hereditary factors
Sometimes the shape of the acromial tuberosity can be excessively prominent and favor friction with the tendon of the supraspinatus muscle.
Poor blood supply to the area and accumulation of micro-crystallized toxins can favor inflammation of the tissues of this joint. This can be caused by stress and an incorrect diet where red meats and sausages, dairy products, sweets…
Other alterations outside the lesional focus
As we know the shoulder joint complex is highly influenced by other adjacent parts of the body that can be a factor that precipitates pathology in the joint, the parts to which we must pay special attention are the cervical and dorsal spine.
Especially if we observe contractures, pain, stiffness prior to shoulder pathology, in that case the physiotherapist should, as we will see in the treatment section, focus part of the treatment on those body areas.
Phases of involvement of subacromial syndrome
Subacromial syndrome occurs in phases.
1. Phase: Edema and inflammation of the supraspinatus tendon
It is a reversible injury that causes pain in the anterior and lateral aspects of the shoulder, which increases at night. Tendinopathy or tendinitis of one or several tendons of the rotator cuff of the shoulder is observed, being the tendon of the supraspinatus muscle the most affected from the beginning. There is tenderness over the supraspinatus tendon and over the acromion. There is a painful arch between 60-120º of abduction, in these cases there is no thickening and no signs of rupture are observed in the radiological tests.
2. Phase: Fibrosis and thickening
In this phase we can find the thickened subacromial serous bag, which increases the compression of the rotator cuff and decreases its friction index with the acromial roof (vault formed by the floor of the acromion and the coracoacromial ligament). We found crepitus, limited mobility, and signs of micro-tears in the fibrous cuff. The most intense pain that manifests is fundamentally at night, but it can appear sporadically during the day and is conditioned by movements of elevation and abduction of the shoulder.
3. Phase: Partial or total rupture of one of several muscles of the rotator cuff
Partial tears of the rotator cuff are found in this phase. A partial or total tear of some of the parts that make up the rotator cuff is observed at the radiological level, with the supraspinatus tendon being the most commonly affected (the most commonly affected tendon within this tendon complex). Two ruptures are distinguished: acute and chronic.
Acute tears are caused by trauma (such as a fall on the shoulder) or lifting a specific weight. These ruptures are sudden, are preceded by acute, intense and persistent pain and do not have to be preceded by a previous tendinopathy or by the previous phases.
Chronic or slowly evolving tears are micro tears that are generated over time and that tear little by little; It is usually preceded by chronic pain that the patient tolerates with analgesics and anti-inflammatories. In both cases, when palpating the greater tuberosity, there will be pain and the patient will feel weakness or impotence when flexing or abducting the shoulder. Chronic tears are caused by degeneration and micro-trauma of the cuff.
Most characteristic symptoms of supraspinatus tendinitis or tendinopathy
The pain of supraspinatus tendinopathy usually appears in the shoulder joint as a dull, diffuse ache on the anterior and lateral sides of the shoulder that becomes much more acute when the shoulder is raised.
On many occasions there is pain radiating down the lateral side of the arm to the elbow. It is also very common for there to be pain and discomfort in the muscles of the neck and cervical spine on the side of the affected shoulder. The onset of pain in supraspinatus tendinopathy may be related to continued work with the arm raised and rotation components, such as the one that could occur when screwing a screw that is above the head.
How is supraspinatus tendinitis or tendinopathy diagnosed?
For the diagnosis of supraspinatus tendinopathy, the following diagnostic methods are used:
Postural and spinal examination and mobility screening tests
We know that the anatomical region of the shoulder is influenced by many joints; the shoulder girdle, as well as the glenohumeral joint, are part of a joint complex that works in unison to provide movement to the upper extremity.
It is essential to examine the correct functioning of the different joints that compose it, since in most cases of tendinopathies in this region the so-called scapulohumeral rhythm is altered , either due to the influence of an incorrect posture or due to muscular alterations that alter the Position of the humeral head in the glenoid cavity.
It is important that the physiotherapist perform a palpatory examination to determine the different structures that may be compromised. The first thing that is done is palpation of the insertion of the supraspinatus tendon, to check that the insertion area is indeed painful on palpation. It will also be important to perform an examination of the muscles to find associated trigger points that we must treat. The position to demonstrate the tendon and adequately palpate it is by performing an internal rotation of the shoulder, as if one were going to undo the bra by throwing the arm back and placing the fingers just below the acromion bone of the shoulder.
Physiotherapists have a wide range of exploratory maneuvers aimed at reducing the subacromial space and compromising the tendon in a controlled way to find and reproduce the painful symptoms. These positions are usually directed towards an elevation and flexion of the arm together with rotation movements, for example putting the hand behind the back, or taking the hand to the opposite shoulder. If the pain increases during the maneuver, then this is a positive sign, which makes us suspect supraspinatus pathology.
Various imaging tests (mainly ultrasound and magnetic resonance imaging)
Once the orthopedic and palpatory tests have been carried out, it is important to carry out imaging tests to more accurately determine the extent of the injury. For this, a simple x -ray and an ultrasound are essential. With the X-ray we will be able to rule out the frequent calcifications in the tendon insertion zones that usually accompany this injury, by means of the ultrasound we will be able to assess the soft structures of the supraspinatus tendon or other adjacent tendons as well as the bursae.
In case of not being clear with the mentioned tests and needing a much more advanced diagnostic detail, magnetic resonance imaging will be the most indicated test.
It is important to indicate that as a general rule, when there are injuries to this tendon, other adjacent structures are also affected. It is common for other affected rotator cuff tendons to appear along with the supraspinatus, as well as the subacromial bursa that is interposed between the acromion and the supraspinatus tendon. When this occurs, it is often referred to as a subacromial syndrome, which is a set of signs and symptoms that indicate that the structures found in the subacromial space are affected to one degree or another.
We must perform a differential diagnosis to verify that it is not a pathology that is not typical of supraspinatus tendinopathy, or that in addition to this pathology there is a problem of the tendon of the long head of the biceps (tendinopathy of the biceps brachii tendon). or an inflammatory process of the joint capsule itself that covers the glenohumeral joint called retractile capsulitis or frozen shoulder. It is also important to point out that there are pains that, although they are located in the arm, have their cause in other areas that reflects your pain in the shoulder.
Physiotherapy treatment of supraspinatus tendinopathy
There are 2 treatments for supraspinatus tendinopathy: conservative and manual and physical therapy.
Conservative physiotherapeutic treatment of supraspinatus tendinopathy
After making a correct diagnosis of supraspinatus tendinitis, we must give way to physiotherapy treatment, which is mainly based on restoring correct joint biomechanics to restore correct mobility to the joint and treat the tendon and periarticular tissues that have been damaged.
Physical and manual therapy located in the area
We have a large battery of techniques that allow us to directly influence the damaged tendon to restore the previous tissue mechanical characteristics, on the muscles that move the shoulder joint, among them we can highlight dry needling, diacutaneous fibrolysis, manual therapy, neurodynamic exercises, muscle stretching, kinesio taping and other therapeutic alternatives, which combined in the right way, are a powerful therapeutic tool for the physiotherapist.
Of all of them I want to highlight the different techniques of manual therapy that the physiotherapist can apply and that are the most characteristic part of our profession. Various manual therapy techniques, such as; Cyriax-type deep transverse massage, decontract, joint manipulation, directed mobilization, will be aimed at treating the rotator cuff muscles as a whole as well as those muscles that perform a function of stabilizing the humeral head in the glenoid cavity (biceps brachii) and those that influence the scapula (rhomboids major and minor, angular scapulae and pectoralis minor, teres major, latissimus dorsi, serratus anterior and trapezius).
What exercises can I do to improve the joint mobility of my shoulder?
The exercises for this type of tendinitis that I recommend should be performed under the supervision of a physiotherapist, since although these may mean a guide with which to guide you, it is important that a physiotherapist personally tells you how to perform them and which of them are the most indicated for your specific case. Each case is different, has its peculiarities and therefore must be addressed individually. We can divide them into:
- Pendulum exercises for shoulder pain and rehabilitation
- Joint mobility exercise
- Rotator cuff reprogramming exercise
- Stretches for the shoulder joint
- Neurodynamic exercise for shoulder pain
How to strengthen the supraspinatus muscle?
To achieve a satisfactory recovery from this injury we must strengthen the supraspinatus muscle.
We must remember that the body always works in a group and that there is no muscle that acts completely alone. For this reason, the exercises that we will present to you now work the entire musculature of the upper limb and not only the supraspinatus muscle.
In this case we bring you exercises with TheraBand (elastic bands with different resistances), but it does not mean that this is the best or the only way to exercise this muscle.
Learn how to tone and strengthen your arms and shoulders with TheraBand
Self-massage for the shoulder for the treatment of supraspinatus tendonitis
Self-massages are very good tools to improve this ailment and will serve to improve circulation in the area.
- Supraspinatus tendonitis and rotator cuff. Self-Massage for your treatment
- Pectoralis minor. Self-massage to loosen and relax this muscle
- General massage for the shoulder. Treatment of tendinitis and other problems
Invasive physiotherapy: an alternative for such a rebellious injury
Invasive physiotherapy includes a set of techniques where an “invasion” of the body is required. That is, we need to penetrate the tissues to be able to reach the injury and thus apply a treatment. Physiotherapy initially did not have these techniques, however it has been shown that in certain pathologies we can directly affect the tissue to generate beneficial effects on it.
One of these invasive physiotherapy techniques is EPI, which stands for Percutaneous Intratissue Electrolysis. Intratissue Percutaneous Electrolysis was invented in the 1960s. Initially it was used only for tendinopathies with very good effectiveness, and even better than other treatments of this type, although little by little it has been found that it can act on other tissues (muscular and ligamentous tissue).
What if supraspinatus tendinitis is complicated by calcification?
Calcifications are deposits of hydroxyapatite that precipitate in the tendon in such a way that it hardens and irritates the tissues surrounding the tendon, generating disabling and persistent pain.
The most recommended imaging test for the diagnosis of shoulder calcification is, in the first instance, an X-ray to determine possible calcifications that may occur in the rotator cuff tendons. Determining the presence of calcifications in the area is important since it will largely condition the performance of the physiotherapist. For these cases, a very good non-invasive alternative is shock waves.
Shock waves are being widely used to treat tendinopathies with added calcifications, it is a great ally to combine them with physiotherapy in these cases.
Other complementary measures that can help you prevent and cure supraspinatus tendinitis
To prevent shoulder tendinitis, in addition to avoiding repetitive and excessive movements in which the joint is in a raised position (example: screwing a lag screw at a height higher than our head in which we have to keep the arm raised and also we must move it to carry out the rotation movement of the arm when screwing) and with rotation components we must avoid activities that excessively require work with the shoulders raised in front of the body, and especially if we work above the shoulder, in this way we request the supraspinatus muscle and also the pectoralis is overloaded, which will favor the alteration of the forces of the shoulder.
Finally, as I have mentioned before, there are other factors that can predispose to tendon problems such as continued stress, poor diet, toxic habits… as a general rule, all those things that alter the proper metabolic functioning are likely to influence the musculoskeletal problems and therefore, from control and knowledge, we can put measures to reduce these negative influences and help our body to face a tendon problem in better conditions. Personally, I give special relevance to these dietary-nutritional measures.
Summary about supraspinatus tendinopathy
- Of the tendinopathies of the shoulder, without a doubt the most frequent is supraspinatus tendinopathy.
- The supraspinatus muscle tendinopathy refers to the inflammation of the structures that surround it due to its anatomical arrangement.
- The characteristic symptom of supraspinatus tendinopathy is pain, accompanied by discomfort in the muscles of the neck and cervical spine.
- For the treatment of supraspinatus muscle tendinopathy, it is necessary that you go to a physiotherapist who establishes a treatment protocol where the correct biomechanics of the shoulder is restored and from there the other aspects to be treated are addressed.
- To prevent supraspinatus tendinopathy it is important to avoid repetitive and excessive movements of the shoulder joint.