What Autoimmune Diseases Cause Carpal Tunnel Syndrome?

Carpal tunnel syndrome (CTS) is a painful condition caused by the compression of the median nerve at the wrist.

• The carpal tunnel is a narrow, tunnel-like passage formed by the bones and ligaments at the base of the hand.
• Important structures such as muscle tendons that help you move your fingers and thumb and the median nerve pass through this tunnel on the palm side of the hand. 
• The median nerve provides sensation to the palmar side of the thumb and the index and middle finger and a part of the ring finger. Additionally, it enables some movements of the thumb.

CTS occurs when the median nerve gets trapped or compressed due to pressure of thickened muscle tendons or swelling within the tunnel. This condition in which a nerve gets compressed or squeezed between some structures in the body is called entrapment neuropathy. CTS is the most common entrapment neuropathy.

The compression of the median nerve causes characteristic symptoms due to its irritation or hampered functioning.

• Symptoms generally begin gradually and may affect one or both the hands although the dominant hand is generally affected before the non-dominant one.
• Symptoms may interfere with falling asleep or waking the person in the morning. They may be more pronounced after continued activity such as typing, painting, holding, or grasping things such as newspapers or books for longer periods and driving.
• Symptoms may be intermittent in the beginning but become more severe and persistent as the disease progresses. 

Symptoms of CTS may include:

• Tingling and numbness, mainly over the thumb, index, and middle finger although it can involve the entire hand, forearm, and arm
• Loss of grip (may complain of things falling off their hands more frequently)
• Pain on the palm side of the wrist that may radiate to the fingers, palm, or forearm
• Swelling or tightness in the hands
• The abnormal temperature of the hands (cold or hot all the time)
• Changes in sweating

Carpal tunnel syndrome (CTS) can occur due to various causes. In some cases, no definitive cause can be found, and the condition may be called idiopathic. In many apparently idiopathic cases, however, further evaluation may unravel the cause to be an autoimmune condition.

CTS is more commonly seen in women than in men. It is more common in the age group 30 to 60 years than in other ages. Studies report that genes may play a role in causing CTS. 

Some of the causes of CTS include:

• Repeated movements such as painting, knitting, typing, or playing sports or musical instruments
• Osteoarthritis of the wrist
• Gout
• Wrist injuries such as strains, sprains, or fracture
• Alcohol
• Smoking
• Obesity
• Autoimmune conditions such as rheumatoid arthritis and systemic lupus erythematosus
• Infections such as human immunodeficiency virus and shingles
• Fluid retention due to conditions such as pregnancy, menopause, or kidney diseases
• Amyloidosis
• Congenital (inborn) conditions affecting the bones of the hand, wrist, or forearm
• Tumors or cysts
• Down syndrome
• Certain medications such as anastrozole (used for breast cancer treatment) and anticoagulants
• Thyroid disorders

Carpal tunnel syndrome (CTS) tends to worsen with time. Hence, early diagnosis and treatment are crucial to prevent or slow the disease progression and manage symptoms.

Treatment mainly depends on the underlying cause and severity of the condition and may include:

• Nonsurgical treatment: Your doctor may choose a conservative approach in most cases particularly when the symptoms are mild. Nonsurgical options include:
  • Pain medications: Nonsteroidal anti-inflammatory drugs, such as ibuprofen and naproxen, may help reduce swelling and pain in mild to moderate cases. 
  • Braces or splints: Your doctor may suggest that you wear a splint while placing your hand in a particular position to avoid further nerve compression. A splint may be worn during the night and while performing certain activities during the day.
  • Physical therapy: Certain exercises such as nerve gliding exercises may help relieve the symptoms. Exercises may be prescribed to reduce excess weight, which may help reduce the symptoms.
  • Activity modifications: Certain activities including leisure or work activities may worsen your symptoms. Your doctor may advise modifying or avoiding such activities if possible. They may suggest ergonomic aids to help prevent the disease progression.
  • Steroid injection: Steroids help lower pain and inflammation. They may be injected into the carpal tunnel to reduce the swelling and resultant compression of the median nerve.
  • Other medications: These include medications such as diuretics or water pills in cases where fluid retention is the cause. Other medications such as vitamin supplements or gabapentin may be given although they have little evidence for their usefulness in CTS. Medications may be given to treat underlying health conditions such as diabetes, kidney disease, and arthritis.
• Surgical treatment: It is generally done in cases where conservative treatment fails, symptoms are worsening, or where there is a structural issue requiring surgical correction such as fractures or abnormal bone growths. The surgery most commonly done is called carpal tunnel release. It may be done through an open or endoscopic approach.