THE CLINICAL SYNDROME

• Scapulocostal syndrome is characterized by a group of symptoms, some of which include referred pain radiating from the deltoid region to the dorsum of the hand, decreased range of motion in the scapula, and unilateral pain and associated paresthesias at the medial border of the scapula.

  • The condition known as scapulocostal syndrome is more commonly known as traveling salesman's shoulder.

  • This is due to the fact that it is commonly observed in people who repeatedly reach backward to retrieve something from the back seat of a car.

• Scapulocostal syndrome is an overuse syndrome that is caused by repeated improper use of the muscles of scapular stabilization.

  • These muscles include the levator scapulae, pectoralis minor, serratus anterior, and rhomboids, as well as infraspinatus and teres minor to a lesser extent.

• On a physical examination, the presence of myofascial trigger points is a prerequisite for diagnosing myofascial pain syndrome, which is the same thing as saying that scapulocostal syndrome is a form of chronic myofascial pain syndrome.

• In spite of the fact that these trigger points are almost always localized to the part of the body that is affected, the pain is frequently referred to other regions.

• This referred pain may be misdiagnosed or attributed to other organ systems, which may then lead to extensive evaluation and treatment that is not successful.

• When a trigger point is mechanically stimulated, either by palpation or stretching, it produces intense local pain as well as referred pain in the surrounding area.

• In addition, myofascial pain syndrome is characterized by an involuntary withdrawal of the stimulated muscle, which is referred to as a jump sign.

  • This phenomenon is frequently observed.

SIGNS AND SYMPTOMS

• The pathologic lesion of scapulocostal syndrome is called the trigger point, and it is characterized by a local point of exquisite tenderness in the infraspinatus muscle.

• This point is located in the middle of the muscle.

• As was mentioned earlier, the most effective way to demonstrate this infraspinatus trigger point is to have the patient place the hand on the affected side of their body over the deltoid of the shoulder on the opposite side.

• There are likely to be additional trigger points located along the medial border of the scapula.

• When the trigger point is mechanically stimulated, either through palpation or stretching, it results in excruciating pain on both the local and referred levels.

• Pain over the infraspinatus muscle that radiates from the shoulder region to the palmar surface of the hand is another symptom of scapulocostal syndrome.

• The jump sign is also indicative of this condition.

TESTING

• The results of biopsies performed on clinically identified trigger points have not revealed abnormal histologic features in a consistent manner.

• The muscle that is home to the trigger points has been variously referred to as "moth-eaten" and as having "waxy degeneration" in its structure.

• Some patients diagnosed with scapulocostal syndrome have been found to have elevated levels of plasma myoglobin, but this finding has not been supported by the findings of any additional researchers.

• An increase in muscle tension has been found in some patients undergoing electrodiagnostic testing for scapulocostal syndrome; however, this finding has not been able to be replicated, so it cannot be considered conclusive.

• Because there isn't an objective diagnostic test for scapulocostal syndrome, the clinician has to rule out any other diseases that may be present at the same time and may have symptoms that are similar.

DIFFERENTIAL DIAGNOSIS

• Clinical findings, as opposed to specific laboratory, electrodiagnostic, or radiographic testing, are used to make the diagnosis of scapulocostal syndrome.

• This is because clinical findings are the most reliable indicator of the condition.

• Because of this, a focused history and physical examination, including a methodical search for trigger points and the identification of a positive jump sign, are required to be performed on every patient who may be suffering from scapulocostal syndrome.

• The clinician needs to rule out other coexisting disease processes that may mimic scapulocostal syndrome, such as primary inflammatory muscle disease, isolated tears of the infraspinatus musculotendinous unit, multiple sclerosis, and collagen vascular disease.

• These conditions are all potential culprits.

• The use of electrodiagnostic and radiographic testing can assist in the diagnosis of coexisting conditions such as tendinitis, bursitis, and tears in the rotator cuff of the shoulder.

• The clinician is responsible for determining whether or not the patient has any coexisting psychological or behavioral abnormalities, as these can either obscure or exacerbate the symptoms of scapulocostal syndrome.

TREATMENT

• The treatment focuses on preventing the myofascial trigger point from activating and achieving a state of prolonged relaxation in the muscle that is being affected.

• When developing a treatment strategy, it is common practice to incorporate an element of trial and error due to the limited understanding of the underlying mechanism of action.

• The first step in treatment is typically conservative therapy, which may include trigger point injections with either a local anesthetic or saline solution.

• Antidepressants are typically prescribed as part of the standard treatment for scapulocostal syndrome.

  • This is due to the fact that many patients suffering from the condition also experience underlying symptoms of anxiety and depression.

• It has also been demonstrated that pregabalin and gabapentin can provide some relief from the symptoms associated with fibromyalgia.

• Milnacipran, which is an inhibitor of the reuptake of both serotonin and norepinephrine, has also been demonstrated to be effective in the treatment of fibromyalgia.

• Nabilone, a synthetic cannabinoid, has also been used to manage fibromyalgia in patients who have not responded favorably to other treatment modalities.

  • These patients have been specifically targeted.

COMPLICATIONS AND PITFALLS

• If one pays close attention to the clinically relevant anatomy, trigger point injections can be performed in a completely risk-free manner.

• In order to prevent infection, sterile technique must be utilized, and universal precautions must be taken in order to lessen the likelihood that the operator will be put in harm's way.

• The majority of complications associated with trigger point injection are due to trauma caused by the needle at the injection site and in the tissues beneath the skin.

• If pressure is applied to the injection site immediately after the injection, this can help reduce the risk of complications such as ecchymosis and hematoma formation.

• It is possible to reduce the risk of trauma to the structures beneath the skin by avoiding needles that are excessively long. When injecting trigger points that are close to the underlying pleural space, one must exercise extreme caution so as to prevent pneumothorax from occurring.