What happens in thoracic outlet syndrome?

Thoracic Outlet Syndrome (TOS) is a medical condition characterized by a group of disorders that occur when there is compression or irritation of the nerves, blood vessels, or both, as they pass through the thoracic outlet. The thoracic outlet is the narrow space between the collarbone (clavicle) and the first rib, through which important nerves and blood vessels travel from the neck to the arm.

1)     What are the three main types of thoracic outlet syndrome?

Neurogenic TOS: This is the most common type and is caused by compression of the brachial plexus, a network of nerves that originates from the spinal cord and controls movement and sensation in the arm and hand.

Vascular TOS: In this type, there is compression of the subclavian artery or vein, leading to symptoms such as swelling, discoloration, and pain in the arm and hand.

Nonspecific or Disputed TOS: This type is less well-defined and may include a combination of symptoms that don’t fit precisely into the other categories.

2)      What are the causes of thoracic outlet syndrome (TOS)?

There are several potential causes of thoracic outlet syndrome, which can be broadly classified into three categories:

• Anatomical factors: Certain anatomical variations or abnormalities can contribute to TOS, including:
• Cervical ribs: Extra ribs located above the first rib can exert pressure on the nerves and blood vessels in the thoracic outlet.
• Abnormal first rib: A congenitally shorter or more rigid first rib can narrow the thoracic outlet space.
• Enlarged muscles or bands: Sometimes, the muscles or fibrous bands in the neck region may become enlarged or develop scar tissue, leading to compression.
• Poor posture and muscle imbalances: Prolonged poor posture, especially if it involves drooping shoulders and forward head position, can put excessive pressure on the thoracic outlet. Additionally, imbalances in the muscles around the neck and shoulders can contribute to TOS.
• Trauma and injuries: Physical trauma, such as car accidents, falls, or repetitive injuries from certain occupations or sports, can damage the structures in the thoracic outlet, leading to inflammation and compression of nerves or blood vessels.

Other factors that may contribute to the development of thoracic outlet syndrome include:

• Repetitive overhead arm movements: Occupations or activities that involve frequent overhead arm movements can put strain on the thoracic outlet area, increasing the risk of compression.
• Weightlifting: Certain weightlifting exercises that involve heavy loads or improper form can stress the thoracic outlet and contribute to TOS.
• Pregnancy: During pregnancy, hormonal changes and weight gain can sometimes lead to temporary compression of nerves or blood vessels in the thoracic outlet.
• Poor posture during sleep: Sleeping in positions that cause the shoulders to round forward can contribute to TOS over time.

3)      What are the Symptoms of TOS?

Recognizing the symptoms of Thoracic Outlet Syndrome is essential to seek timely treatment. The signs may manifest differently depending on which structures are affected. Common symptoms include:

• Shoulder Pain: Persistent or intermittent pain in the shoulder region, often radiating down the arm.
• Numbness and Tingling: Feelings of pins and needles in the arm and hand.
• Muscle Weakness: Weakness in the affected arm, leading to difficulties in gripping or lifting objects.
• Swelling: Swelling in the arm or hand due to compromised blood flow.
• Discoloration: Bluish discoloration of the arm or hand due to poor circulation.
• Cold Sensation: Feeling unusually cold in the affected arm or hand.

4)     How to diagnose Thoracic Outlet Syndrome?

Diagnosing TOS can be challenging, as its symptoms often overlap with other medical conditions. The diagnostic process may include:

1. Medical History and Physical Examination:

Your healthcare provider will start by gathering your medical history and conducting a physical examination. During the exam, they will assess your range of motion, and muscle strength, and check for any noticeable abnormalities.

• Imaging Tests:

Imaging tests, such as X-rays, MRI (Magnetic Resonance Imaging), and CT (Computed Tomography) scans, may be ordered to visualize the thoracic outlet and its structures. These tests help rule out other possible causes of your symptoms.

• Electrodiagnostic Studies:

Nerve conduction studies and electromyography (EMG) can help identify nerve compression and evaluate nerve function.

• Injection Tests:

In some cases, your doctor may perform injection tests to pinpoint the specific nerves or blood vessels causing your symptoms. These tests involve injecting a local anesthetic into the affected area to temporarily relieve the pain and confirm the diagnosis.

Special tests:

There are several special tests that can help diagnose or evaluate Thoracic Outlet Syndrome. Here are some commonly used ones:

• Adson’s Test: This test is performed to assess compression of the subclavian artery. The patient is asked to take a deep breath and hold it while turning their head to the affected side. The examiner then checks the pulse at the wrist. A decrease in the pulse or reproduction of symptoms may indicate compression of the artery.
• Roos Test (EAST Test – Elevated Arm Stress Test): This test helps assess compression of the neurovascular structures. The patient is asked to open and close their hands for about 3 minutes while holding their arms abducted at a 90-degree angle and slightly forward. If the patient experiences weakness, numbness, or tingling, it may suggest Thoracic Outlet Syndrome.
• Wright Test (Hyperabduction Test): This test helps evaluate compression of the neurovascular structures as the patient’s arm is abducted overhead. The examiner monitors for any signs of neurological symptoms or changes in the pulse.
• Costoclavicular Maneuver: In this test, the patient is asked to bring their shoulders back and down while sticking their chest out. This position compresses the thoracic outlet, and the examiner checks for any reproduction of symptoms or vascular changes.
• Halstead Maneuver (Military Brace Position): The patient is instructed to bring their shoulders back and down while squeezing their shoulder blades together, simulating the military brace position. The examiner assesses for any symptoms or changes in pulses.

5)     The Role of Physical Therapy in Treating TOS:

Physical therapy plays a crucial role in managing Thoracic Outlet Syndrome. A skilled physical therapist can design a personalized treatment plan to relieve symptoms, improve posture, and restore function. Here are some key components of physical therapy for TOS:

1. Manual Therapy:

Hands-on techniques, such as soft tissue mobilization and joint mobilization, can help reduce muscle tension and improve joint flexibility in the affected area.

• Postural Exercises:

Postural exercises are essential to correct any imbalances that might contribute to TOS. Strengthening the muscles that support proper posture can alleviate pressure on the thoracic outlet.

• Nerve Gliding Exercises:

Nerve gliding exercises aim to improve the mobility and function of compressed nerves, reducing symptoms like tingling and numbness.

• Strengthening Exercises:

Targeted strengthening exercises focus on building the muscles around the shoulder and neck to support better posture and reduce strain on the thoracic outlet.

• Stretching Exercises:

Stretching is vital to maintain flexibility and prevent muscle tightness, which can exacerbate TOS symptoms.

• What are Precautions and lifestyle modifications for TOS?

Alongside physical therapy, certain precautions and lifestyle modifications can significantly contribute to managing TOS effectively:

1. Ergonomics:

Ensure your workspace is ergonomically optimized to support good posture and minimize strain on your upper body.

• Regular Breaks:

If your work involves repetitive movements or prolonged sitting, take regular breaks to stretch and change positions.

• Avoid Lifting Heavy Objects:

Limit lifting heavy objects, especially with poor posture, to prevent aggravating TOS symptoms.

• Stay Active:

Engage in low-impact exercises regularly to maintain overall health and flexibility.

What kind of exercises are best for thoracic outlet syndrome?

These are some exercises for TOS patients:

Scapular Retraction:

• Sit or stand with your back straight.
• Squeeze your shoulder blades together and hold for 5-10 seconds.
• Release and repeat for 10-15 repetitions.

Shoulder External Rotation Stretch:

• Stand with your back against a wall, elbows bent at 90 degrees, and palms facing forward.
• Slowly slide your arms up the wall, keeping your elbows bent, until you feel a gentle stretch in your shoulders and chest.
• Hold the stretch for 15-30 seconds and then slowly lower your arms back down.
• Repeat for 3-5 repetitions.

Neck Stretch:

• Sit or stand with your back straight.
• Tilt your head to the right, bringing your right ear toward your right shoulder.
• Hold the stretch for 15-30 seconds, feeling a gentle stretch along the left side of your neck.
• Repeat on the other side.
• Do 3-5 repetitions on each side.

Pectoral Stretch:

• Stand in a doorway with your arms at shoulder height and bent at 90 degrees.
• Place your forearms against the door frame and step forward with one foot until you feel a stretch in your chest.
• Hold the stretch for 15-30 seconds and then step back.
• Repeat for 3-5 repetitions.

Upper Trapezius Stretch:

• Sit or stand with your back straight.
• Gently tilt your head to the right, bringing your right ear toward your right shoulder.
• Reach your right arm over your head and place your hand on the left side of your head.
• Apply gentle downward pressure with your hand to increase the stretch in your neck and upper trapezius.
• Hold for 15-30 seconds and then switch sides.
• Do 3-5 repetitions on each side.

Thoracic Extension:

• Sit on a stability ball or chair with your back straight.
• Place your hands behind your head, elbows pointing out to the sides.
• Arch your upper back gently, leaning back slightly over the ball or chair.
• Hold the position for a few seconds and then return to the starting position.

Repeat for 10-15 repetitions.