Shoulder pain

As with the diagnosis of many other pathological conditions, the diagnostic algorithm for pain in the shoulder area is simplified by first dividing possible pathological conditions into two groups depending on the nature of the onset of the disease (acute, gradual).

I. Acute onset:

1. Frozen shoulder syndrome
2. Neuralgic brachial amyotrophy
3. Lateral cervical intervertebral disc herniation
4. Metastatic lesion of the cervical spine
5. Inflammatory diseases of the cervical spine
6. Herpes zoster
7. "Whiplash"
8. Spinal epidural hemorrhage.

II. Gradual start:

1. Degenerative and other diseases of the spine at the cervical level
2. Extramedullary tumor at the cervical level
3. Pancoast tumor
4. Syringomyelia and intramedullary tumor
5. Arthrosis of the shoulder joint
6. Brachial plexus lesions
7. Postherpetic neuralgia
8. Tunnel neuropathy of the suprascapular nerve
9. Regional psychogenic pain

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Gradual onset of pain in the shoulder area

Degenerative and other diseases of the spine at the cervical level

In degenerative processes of the cervical spine, clearly defined radicular pain and sensory disturbances occur infrequently; the same applies to motor symptoms of muscle weakness or loss of reflexes. This is explained by the fact that the symptoms, as a rule, are not a consequence of compression of the spinal roots; the source of pain is more often the intervertebral joints, which are richly innervated by sensory fibers. Referred pain occurs in the shoulder area - this pain has a more diffuse distribution, with it there are no segmental sensory or motor disorders (symptoms of loss). Movements in the neck are limited, but they do not necessarily provoke pain. Shoulder movements are free; limitation of movement in the shoulder may occur with secondary wrinkling of the joint capsule due to immobilization of the proximal arm.

The source of pain may be other diseases of the spine: rheumatoid arthritis, ankylosing spondylitis, osteomyelitis.

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Extramedullary tumor at the cervical level

In contrast to degenerative spinal pathology, extramedullary tumors tend to damage the corresponding nerve root at a fairly early stage of the disease, since more than half of the cases are neurinomas originating from the posterior root. Meningiomas occur mainly in women (95%) and are often localized on the posterior surface of the spinal cord. There is radicular pain in the shoulder area, which increases with coughing. Sensory disturbances and changes in reflexes occur at an early stage of the disease. It is extremely important to detect the involvement of one or two nerve roots, since the diagnosis must be established before signs of damage to the spinal cord itself appear, which may be irreversible. Electrophysiological studies require significant skill and experience. X-rays may not reveal pathological changes. Cerebrospinal fluid analysis, neuroimaging studies and CT myelography are necessary.

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Pancoast tumor

Pain in the area of innervation of the lower trunk of the brachial plexus, i.e. along the ulnar surface of the arm to the hand, occurs at a fairly late stage of the disease. If the patient has ipsilateral Horner's syndrome, then there is usually no alternative to the diagnosis of "Pancoast tumor" (with the exception of syringomyelia).

Syringomyelia and intramedullary tumor

The initial symptom of syringomyelia may be radicular pain in the shoulder area, since the cavity in the spinal cord exerts pressure on both the lateral horn of the spinal cord (i.e., the preganglionic part of the peripheral sympathetic tract) and the posterior horn (i.e., the zone of entry of segmental sensory information into the spinal cord). As a rule, the pain is not clearly limited to one or two segments, but occurs diffusely throughout the arm. At this stage of the disease, ipsilateral central Horner's syndrome and paralysis of sweating on the half of the face ipsilateral to the lesion, the ipsilateral shoulder, and the proximal parts of the arm may be observed.

Another possible diagnosis is an intramedullary tumor, usually benign. The key to prognosis in both syringomyelia and intramedullary tumors is early diagnosis: in both diseases, the spinal cord damage is already irreversible if the diagnosis is made when the patient already has segmental muscular atrophy due to anterior horn damage, or spastic paraplegia due to pyramidal tract damage, or transverse spinal cord damage with characteristic loss of pain and temperature sensitivity. Neuroimaging studies are mandatory, preferably in combination with myelography.

Arthrosis of the shoulder joint

With arthrosis of the shoulder joint, there may be reflected pain in the shoulder area, in the proximal parts of the arm without sensory impairment or motor defect. A characteristic feature is a gradual limitation of mobility in the shoulder joint and pain that occurs when abducting the arm.

Other conditions (similar in pathogenesis): shoulder-hand syndrome, epicondylosis of the shoulder.

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Brachial plexus lesions

Trauma, tumor infiltration, radiation plexopathy and other diseases that can be accompanied by pain in the shoulder area include scalene muscle syndrome (the four lower cervical spinal nerves that form the brachial plexus, upon exiting the intervertebral foramina, are located first in the interscalene space between the anterior and middle scalene muscles), upper trunk syndrome (V and VI cervical nerves), middle trunk syndrome (VII cervical nerve), lower trunk syndrome (VIII cervical and first thoracic nerve) and other plexopathic syndromes.

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Postherpetic neuralgia

Postherpetic neuralgia is often mistaken for pain symptoms associated with degenerative pathology of the spine, which is facilitated by the elderly age of patients and the fact that X-ray examination is performed not after a clinical examination, as it should be done, but before it. With postherpetic neuralgia, the pain is much more intense and debilitating compared to pain in osteochondrosis of the spine and does not change with movement or coughing. As a rule, it is possible to detect the consequences of existing herpetic eruptions in the form of hyperpigmentation areas located in the area of the corresponding segment.

Tunnel neuropathy of the suprascapular nerve

This rare syndrome is usually associated with trauma or develops spontaneously. It is characterized by deep pain at the upper edge of the scapula. Abduction of the shoulder increases the pain. Weakness of the m. infraspinatus m. supraspinatus is revealed. A typical pain point is found at the site of nerve compression.

Regional psychogenic pain

Finally, the patient may have local regional pain in the shoulder area of psychogenic origin. This condition is quite common, but such a diagnosis should be made with caution, as with psychogenic pain syndromes of other localizations. The absence of any deviations according to neurological and additional research methods cannot fully guarantee the absence of a neurological or somatic cause of the local pain syndrome. Therefore, in parallel with the prescription of antidepressants with an analgesic effect, it is advisable to conduct dynamic observation; regular repeated examination and examination, analysis of mental status and objective anamnesis, i.e. anamnesis collected from close relatives should not be neglected.

Shoulder pain may also occur with anterior scalene syndrome, pectoralis minor syndrome, posterior cervical sympathetic syndrome, carotid artery dissection, carotidynia, tumor in the jugular foramen, retropharyngeal space infection, skin and subcutaneous tissue diseases, hemiplegia (a variant of frozen shoulder syndrome); as well as with some other diseases (polymyositis, polymyalgia rheumatica, osteomyelitis, fibromyalgia, subclavian artery occlusion). However, these diseases differ significantly in the topography of the pain syndrome and have characteristic additional clinical manifestations that allow them to be recognized.

Sharp pain in the shoulder area

Frozen shoulder syndrome

The term "frozen shoulder" is usually used to describe a symptom complex that most often develops at the final stage of a gradually developing pathology of the shoulder joint (scapulohumeral periarthropathy syndrome). In such cases, radiography of the shoulder joint reveals arthrosis and/or calcium deposits in the lateral parts of the joint capsule. However, sometimes this syndrome develops acutely: pain in the shoulder and referred pain in the arm appear, forcing the patient to avoid movements in the shoulder joint. Movements in the neck do not affect the pain or only slightly increase it; an increase in cerebrospinal fluid pressure also does not affect the intensity of the pain. When the arm is abducted, intense pain and reflex contraction of the muscles of the shoulder girdle occur. In this condition, motor functions are very difficult to examine. Deep reflexes are not reduced, there are no sensory disorders. Myofascial syndrome often underlies such a clinical picture.

In this case, the trigger point is often detected first in the subscapularis muscle, then in the pectoralis major and minor muscles, in the latissimus dorsi and in the triceps brachii (less often in other muscles). Movement in the shoulder joint is limited by pain and muscle spasm, which in this case is part of the pain response. Secondary changes in the tendons and tissues of the spasmodic muscles are possible.

Neuralgic brachial amyotrophy (Parsonage-Turner syndrome)

The disease develops acutely. As a rule, the dominant hand is involved (in most cases, the right one). Mostly young men are affected. The main symptom is intense pain in the shoulder area and proximal parts of the arm, which can spread down the radial surface of the forearm to the thumb. After a few hours or on the second day of the disease, there is a limitation of movement in the shoulder due to weakness of the muscles of the shoulder girdle and pain, which increases with arm movements. An important differential diagnostic criterion that allows excluding a herniated disc is the absence of an increase in pain with movements in the neck.

The degree of muscle weakness can be assessed by the end of the first week of the disease, when the pain becomes dull. The neurological status reveals symptoms of damage to the motor fibers of the upper part of the brachial plexus. Most patients have paresis of the deltoid, anterior serratus, and supraspinatus muscles. The biceps brachii may be involved. In rare cases, isolated paresis of one muscle is determined, for example, the serratus or diaphragm. Rapid development of muscle atrophy is characteristic. Reflexes are usually preserved; in some cases, the reflex from the biceps brachii may decrease. There are no sensory disorders (except for transient pain) or they are minimal, which is explained by the fact that the affected part of the brachial plexus contains mainly motor fibers (with the exception of the axillary nerve, the innervation zone of which is located on the outer surface of the upper part of the shoulder and is comparable in area to the area of the palm).

When studying the speed of nerve conduction, a slowdown in the conduction of excitation along the brachial plexus is revealed. By the end of the 2nd week of the disease, EMG reveals signs of denervation of the muscles involved. There are usually no changes in the cerebrospinal fluid with this disease, so in the presence of a characteristic clinical picture, a lumbar puncture is not necessary. The prognosis is favorable, however, functional recovery may take several months. The pathogenesis is not entirely clear.

Lateral cervical intervertebral disc herniation

An excessive load is not necessary for the formation of a herniated disc at the cervical level. The fibrous ring involved in the degenerative process is very thin, and its rupture can occur spontaneously or during the most ordinary movement, for example, when stretching the arm. The patient develops radicular pain. The most diagnostic value is a fixed position of the head with its slight tilt forward and to the painful side. Movements in the neck, especially extension, are more painful than movements in the arm.

Examination of reflexes from the arm at the acute stage of the disease (when the patient has not yet been able to at least partially adapt to acute pain) is usually of little information; the same applies to examination of sensitivity. There are no abnormalities in the EMG examination. Degenerative changes in the spine may not be detected in radiography; a decrease in the height of the intervertebral space should not necessarily be expected in all cases. Neuroimaging methods (CT or MRI) can reveal protrusion or prolapse of the intervertebral disc. It is extremely important to detect compression of the cervical root in the posterolateral angle of the cervical canal or compression of the spinal cord itself, which is clinically manifested by an increase in deep reflexes from the limb below the presumed level of damage and impaired sensitivity in the trunk. Some patients develop the clinical picture of Brown-Sequard syndrome.

Metastatic lesion of the cervical spine

In the case of metastasis to the cervical spine, acute radicular pain in the shoulder area without a previous, fairly long period of local pain rarely occurs. If the anamnesis indicates previous local pain, it is usually mistakenly interpreted as a manifestation of degenerative pathology of the spine (a common mistake).

Making a correct diagnosis based only on the anamnesis and neurological status assessment is almost impossible at first (!). The symptoms are very similar to the manifestations of the discogenic process. A certain indication of the possibility of metastatic damage may be the level of segmental disorders: herniated discs located above the sixth cervical segment are extremely rare. Laboratory tests can provide useful information, however, every doctor knows cases of the metastatic stage of the tumor process with normal ESR values. The most informative are neuroimaging and radiography, based on the results of which, if necessary, myelography is performed, which is conveniently combined with neuroimaging. In the case when the patient does not have a complete transverse lesion of the spinal cord, time should not be wasted searching for the primary localization of the tumor process. The patient is shown surgical intervention, which, on the one hand, allows for decompression of the spinal cord, and on the other - to obtain material for histological examination.

Inflammatory diseases of the cervical spine

Spondylitis has become a fairly rare pathology. Spondylitis causes local and referred pain in the shoulder area. The diagnosis is established based on X-ray or neuroimaging data. Intervertebral discitis may be a consequence of surgical treatment of a herniated disc. The patient experiences pain with any movement in the spine and referred radicular pain. There are usually no changes in the neurological status, with the exception of reflex immobilization of the affected part of the spinal column. The diagnosis is based on X-ray examination.

Approximately 15% of all epidural abscesses occur at the cervical level. The clinical manifestations of an epidural abscess are very pronounced. The patient experiences acute, unbearable pain, leading to immobilization of the spinal column. Symptoms of spinal cord compression develop rapidly, which overlap the less pronounced radicular symptoms. Laboratory studies reveal pronounced "inflammatory" changes, a significant increase in ESR. Conducting neuroimaging studies is problematic, since the level of localization of the lesion is difficult to determine clinically. The best method is computed tomography in combination with myelography, which makes it possible to take cerebrospinal fluid for examination. In those rare cases when epidural compression is caused by a tumor or lymphoma, cytological examination of cerebrospinal fluid provides important information.

Herpes zoster

In the first 3-5 days of the disease, when there are no vesicular eruptions in the area of a certain segment, it is difficult or even impossible to diagnose herpes zoster, since at this stage the only manifestation is radicular pain. Pain in the shoulder area usually has a burning character, comparable to the sensation of a skin burn; the pain is constant and does not increase with movement or with an increase in cerebrospinal fluid pressure (for example, when coughing). By the end of the first week, the diagnosis due to skin eruptions becomes uncomplicated. In rare cases, symptoms of loss in the motor sphere are possible - loss of deep reflexes and segmental paresis.

"Whiplash"

This specific injury to the cervical spine occurs in car accidents when a moving or stationary car is hit from behind by a car traveling at a higher speed. The slow-moving car first accelerates sharply, then decelerates sharply, which causes, accordingly, overextension of the passenger's neck (hyperextension injury), quickly replaced by its excessive flexion. This leads to damage mainly to the intervertebral joints and ligaments.

A few hours or the next day after the injury, pain appears along the back of the neck, forcing the patient to hold the neck and head still; the pain radiates to the shoulder and arm. This painful condition can last for several weeks. Reflexes are intact, there are no sensory disorders, electrophysiological and radiological studies do not reveal pathology. The diagnosis is made taking into account the specific anamnesis. It is quite difficult to objectively assess the real duration and severity of pain.

Spinal epidural hemorrhage

Spinal epidural hemorrhage is a rare disorder characterized by sudden onset of severe pain, often with a radicular component, and rapid development of lower paraplegia or tetraplegia. The most common cause is anticoagulant therapy. In 10% of cases, there is a vascular anomaly (usually cavernous angioma). One third of all hemorrhage cases develop at the level between the C5 and D2 segments. MRI or CT reveals a hematoma. The prognosis depends on the severity and duration of the neurological deficit.

Differential diagnosis includes acute transverse myelitis, anterior spinal artery occlusion, acute subarachnoid hemorrhage, aortic dissection, and spinal cord infarction.