Einführung

Thoracic outlet syndrome is a manifestation of compression of neurovasculature that passes through the thoracic outlet made of the clavicle and first rib. Common symptoms of thoracic outlet syndrome include paraesthesia of the upper extremity and the onset of pain. The following sections discuss the therapeutic modalities for the treatment of thoracic outlet syndrome.   

What is Thoracic Outlet Syndrome?

The thoracic outlet is made of the clavicle and the first rib and scalene muscles. Thoracic outlet syndrome refers to a set of conditions that include compression of neurovasculature passing through the thoracic outlet. Neurogenic thoracic outlet syndrome is the most common variant of thoracic outlet syndrome attributing to 90% of the total cases. Thoracic outlet syndrome is more common in females and individuals with poor posture or improper muscle development. [1]

Symptoms of Thoracic Outlet Syndrome 

The symptoms of neurogenic thoracic outlet syndrome include the following. 

1. Paraesthesia of the finger(s)
2. Upper extremity paresthesia 
3. Occipital headache 
4. Neck pain – it may radiate to the following regions
   1. Occiput and regions superior to the ear
   2. Rhomboid area
   3. Upper pectoral region
   4. Deltoid and trapezius muscle regions 
   5. The outer region of the arms
   6. The inner region of the arm
5. Trapezius pain
6. Chest pain
7. Schulterschmerzen
8. Arm pain
9. Supraclavicular pain 

The symptoms of venous thoracic outlet syndrome, also called Paget-von Schroetter syndrome, include the following. 

1. Swelling, cyanosis, and pain in the upper extremity
2. Unilateral Raynaud-like symptoms
3. Effort thrombosis 

The symptoms of relatively rare arterial thoracic outlet syndrome include the following. 

1. Acute ischemia of the distal upper extremity 
2. Neurologic abnormalities [2]

Other symptoms of thoracic outlet syndrome include muscle wasting, weakened grip, fatigue of arms, cold extremities, and weak pulse in the affected upper extremity. 

Causes and Risk Factors of Thoracic Outlet Syndrome

The primary cause of thoracic outlet syndrome is increased pressure that compresses nerves and/or vessels coursing through the thoracic outlet. Structural and physiological abnormalities that contribute to this pressure include the following. Both trapezius muscle deficiency and clavicle fracture lead to compression of the neurovasculature passing through the thoracic outlet. [1]

1. Thoracic ribs
2. Space-occupying lesions such as cysts and tumors
3. Fibrous muscular bands 
4. Previous trauma such as car accidents 
5. Abnormal positioning of the neck 
6. Deficiency of trapezius muscle 
7. Clavicle fracture 

Pregnancy and occupational activities involve repetitive overhead motion of the upper extremity. 

Diagnosis of Thoracic Outlet Syndrome

The physical exam is the initial step in the diagnosis of thoracic outlet syndrome. The diagnosis is confirmed using laboratory testing and imaging that includes chest or cervical spine x-ray and ultrasound. Angiography is important for the diagnosis of arterial thoracic outlet syndrome. Venous dopplers are beneficial for the diagnosis of venous thoracic outlet syndrome. Neurogenic thoracic outlet syndrome is diagnosed using electrodiagnostic studies. [1]

Normaler Heilungszyklus 

The normal healing cycle comprises the phases mentioned below. [3] 

1. Entzündungsstadium 

During this phase of the healing cycle, the inflammatory cells arrive at the site of injury. These cells secrete inflammatory mediators which give rise to swelling, pain, redness, and warmth at the affected site. Inflammation aims to eradicate the agent that elicited the inflammatory response.

2. Proliferationsphase 

The inflammation stage is followed by the onset of the proliferation stage, characterized by the development of the scar tissue. During this stage, the formation of new blood vessels, deposition of collagen by fibroblasts, and re-epithelization take place. In case of excessive scar tissue formation, muscle trigger points and fascia restrictions may arise. 

3. Reifephase 

The stage is characterized by the recovery of the injured tissues. The previous two reactions are ceased and the affected area is cleared off the inflammatory cells and mediators. This is the final and desired stage in the process of wound healing. 

Acute inflammation resolves within a few days and is characterized by a normal healing cycle. On the contrary, chronic inflammation may continue for up to several months to years. In the case of chronic inflammation, the wound healing cycle oscillates between the proliferation and inflammation phases of the healing cycle. In chronic inflammation, the injured tissue fails to attain recovery. 

Ineffective Treatments of Thoracic Outlet Syndrome

Individuals suffering from thoracic outlet syndrome may opt for the following therapeutic techniques. However, the mentioned techniques do not involve proliferation and inflammation stages of the healing cycle.

1. Elektrische Stimulation des betroffenen Bereichs
2. Nachrichtentherapie 
3. Massagetherapie mit der Faszienrolle 
4. Thermal treatment including heat and ice therapy 
5. Kraftübungen während der Entzündungsphase des Heilungszyklus
6. Dehnung 

Effective Treatments of Thoracic Outlet Syndrome 

Following are the important components of the treatment regimen for thoracic outlet syndrome. The rational treatment involves the resolution of both inflammation and proliferation stages of the healing cycle. Proper therapeutic techniques also promote the progression of the healing cycle to the maturation or recovery phase. 

1. One shall refrain from performing repetitive movements that trigger pain. 
2. Following tools play a significant role in the resolution of the inflammatory stage. 
   1. Consumption of an anti-inflammatory helps in the management and reduction of inflammation. 
   2. MagnaHeal is a device that uses magnetic therapy to manage and resolve inflammation. MagnaHeal 1 is useful for the treatment of mild inflammation. In contrast to that, MagnaHeal 2 is beneficial for the treatment of severe inflammation. [4]
   3. Nutrient deficiencies may also manifest as excessive inflammation. AskASTR is useful for the identification of nutrient deficiencies and the determination of essential supplements that help resolve inflammation. 
   4. One shall take adequate rest to promote healing. 
3. Following tools play a significant role in the resolution of the proliferation stage. [5]
   1. A1 tools are employed for releasing superficial and aponeurotic fascia restrictions. 
   2. A3 tools are employed for releasing superficial scar tissue as well as muscle knots or trigger points. 
   3. A5 tools are employed for releasing deep scar tissue, trigger points or muscle knots, and fascia restrictions of epimysium, endomysium, and perimysium. 

Fazit 

Individuals often use ineffective therapeutic techniques such as ice and heat therapy, electrical stimulation, massage therapy, stretching, and strengthening exercises to alleviate symptoms of thoracic outlet syndrome. However, resolution of the inflammation and proliferation stages of the healing cycle are important strategies for the treatment and management of thoracic outlet syndrome.  

Verweise

1. https://www.ncbi.nlm.nih.gov/books/NBK557450/ 
2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6514035/ 
3. https://www.ncbi.nlm.nih.gov/books/NBK518964/ 
4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3617815/
5. https://pubmed.ncbi.nlm.nih.gov/30252294/