

Carpal Tunnel Syndrome: Causes, Symptoms, and Risk Factors
A 45-year-old business analyst was discussing statistics comparing developed and undeveloped nations with his friend while playing table tennis. They talked about pivoting financial strategies as part of their mission, ‘India 2047’.
For the past few weeks, he had occasionally noticed numbness, tingling, and mild clumsiness in his fingers, especially after long hours of typing and late at night, but he had ignored these symptoms.
While playing table tennis that day, the repetitive wrist movements seemed to aggravate his condition. He suddenly experienced increased pain, weakness, and a pins-and-needles sensation in his fingers, but continued to play, thinking it would subside.
Later, while trying to open the doorknob of his car, he felt a sharp, burning pain in his wrist and fingers, with noticeable weakness, making it difficult to grip. Concerned, he drove to the hospital.
After a detailed history and physical examination, including a positive Phalen’s test and Tinel’s sign, the doctor diagnosed him with Carpal Tunnel Syndrome (CTS). The doctor explained that his symptoms were likely due to repetitive wrist strain from prolonged computer use, worsened by the sudden repetitive stress while playing table tennis.
Introduction
Carpal Tunnel Syndrome (CTS) affects approximately 3–4% of the global population. Studies estimate an incidence of around 88 per 100,000 males and 193 per 100,000 females, making it more common in women. The condition is most prevalent in individuals aged 40 to 60 years.
The higher incidence in women is linked to hormonal factors such as pregnancy and menopause.
- During pregnancy, especially in the third trimester, hormonal fluctuations, increased fluid retention (edema), and nerve hypersensitivity elevate the risk of CTS.
- In postmenopausal women, estrogen deficiency contributes to inflammation in synovial tissues, including those in the wrist, increasing the likelihood of median nerve compression.
- Additionally, changes in estrogen receptor expression may influence joint health and inflammation, further raising CTS risk.
Carpal Tunnel Anatomy

The carpal tunnel is a narrow, rigid passageway located in the wrist. It is formed by:
- The transverse carpal ligament (also known as the flexor retinaculum), which acts as the roof of the tunnel. This ligament is strong and slightly flexible, providing stability while allowing limited movement.
- The carpal bones, which form the floor and sides of the tunnel, creating a concave structure.
Within this tunnel pass:
- Nine flexor tendons (which help bend the fingers and thumb), including:
- Four flexor digitorum superficialis tendons
- Four flexor digitorum profundus tendons
- One flexor pollicis longus tendon (for thumb movement)
- The median nerve, which controls sensation in the thumb, index, middle, and part of the ring finger, as well as motor function for some hand muscles.
The narrow structure of the carpal tunnel makes the median nerve vulnerable to compression, leading to symptoms of Carpal Tunnel Syndrome (CTS) when the space becomes restricted.
What is Carpal Tunnel Syndrome?
Carpal Tunnel Syndrome (CTS) is a condition caused by compression of the median nerve as it passes through the carpal tunnel in the wrist. The median nerve provides sensation to the thumb, index finger, middle finger, and the lateral half of the ring finger, and controls some muscles at the base of the thumb.
When compressed, it leads to symptoms such as:
- Numbness
- Tingling (pins and needles sensation)
- Pain in the affected fingers, often making people feel like the entire hand is involved
CTS can affect one or both hands, depending on the cause. In chronic or severe cases, it may lead to weakness and wasting (atrophy) of the thenar eminence—the group of muscles at the base of the thumb, affecting grip strength.
Frequent wrist flexion can increase pressure in the carpal tunnel by more than 8 times, while extension can raise it by 10 times, contributing to nerve compression. Wrist injuries can cause swelling and increased pressure. Apart from this, diseases like rheumatoid arthritis cause joint inflammation, increasing pressure and leading to ischemic damage of the median nerve.
What are the Stages of Carpal Tunnel Syndrome?
- Stage 1 (Early Stage):
- Symptoms: Numbness, tingling, or a sensation of swelling in the hand, often causing the patient to wake up at night.
- Pain: May radiate from the fingers and hand to the wrist and even the shoulder.
- Observation: No visible swelling despite the sensation.
- Stage 2 (Intermediate Stage):
- Symptoms: Persistent pain and numbness in the hand, wrist, and fingers, especially during activities involving repetitive hand movements (e.g., typing, using vibratory tools like a crane operator).
- Impact: Symptoms occur both during activity and sometimes at rest.
- Stage 3 (Advanced Stage):
- Symptoms: Weak grip strength, difficulty holding objects, and noticeable muscle wasting at the base of the thumb (thenar atrophy).
- Impact: Significant functional impairment, making daily tasks challenging.
What are the Symptoms of Carpal Tunnel Syndrome?

Common symptoms of Carpal Tunnel Syndrome (CTS) include:
- Weakness when trying to hold or grip objects with one or both hands.
- Pain or numbness in the hand(s), especially affecting the thumb, index finger, middle finger, and the lateral half of the ring finger.
- A “pins and needles” sensation (also known as paresthesia) in the fingers.
- Burning or tingling sensations, particularly in the affected fingers.
- Pain or numbness that worsens at night, often severe enough to interrupt sleep.
These symptoms may initially be intermittent but can become constant as the condition progresses, potentially affecting daily activities and grip strength.
Diagnosis of Carpal Tunnel Syndrome
When you visit your doctor, they may perform the following clinical tests to confirm the diagnosis:
- Tinel’s Sign:
- The doctor gently taps over the carpal tunnel area on your wrist.
- A positive Tinel’s sign is indicated if this tapping causes sensations of pain, numbness, or “pins and needles” in the fingers supplied by the median nerve.
- Phalen’s Maneuver (Wrist Flexion Test):
- You’ll be asked to flex your wrists at a 90-degree angle, pressing the backs of your hands together (like a reverse prayer position), and hold this position for 30–60 seconds.
- A positive Phalen’s test occurs if you experience tingling, numbness, or pain in the fingers, indicating median nerve compression.
Causes of Carpal Tunnel Syndrome
Carpal Tunnel Syndrome (CTS) occurs due to compression of the median nerve as it passes through the carpal tunnel in the wrist. This compression can result from various conditions that cause
- Swelling
- Inflammation
- Structural changes in the wrist
- Repetitive Strain Injury (RSI):
- Repetitive finger and hand movements during activities like typing, writing, or playing video games for prolonged periods.
- This repetitive motion can lead to overuse of muscles and tendons, causing inflammation, which increases pressure on the median nerve.
- Arthritis of the Wrist Joints:
- Conditions like rheumatoid arthritis or osteoarthritis lead to joint inflammation, causing swelling and stiffness.
- The inflammation narrows the carpal tunnel, compressing the median nerve.
- Wrist Fractures:
- Traumatic injuries such as car accidents falls, or sports-related incidents can result in wrist fractures.
- The fractured bones, along with swelling and possible displacement, can compress the median nerve. Additionally, the transverse carpal ligament, which forms the tunnel’s roof, may contribute to this compression.
- Wrist Sprains:
- A sprain involves injury to the ligaments that hold the carpal bones together, often due to sudden twisting, falls, or overextension.
- The resulting pain, swelling, and ligament instability can lead to increased pressure on the median nerve.
- Genetic Disorders (e.g., Mucopolysaccharidosis):
- Mucopolysaccharidosis (MPS) is an autosomal recessive disorder characterized by the accumulation of glycosaminoglycans (GAGs)—complex sugars that regulate water balance in tissues.
- The excessive buildup of GAGs in the ligaments and tendons within the carpal tunnel leads to thickening and reduced space, causing median nerve compression.
Risk Factors for Carpal Tunnel Syndrome
Several factors can increase the risk of developing Carpal Tunnel Syndrome (CTS) by contributing to median nerve compression within the carpal tunnel:
- Anatomical Changes:
- Small-sized Carpal Tunnel: A naturally narrow carpal tunnel leaves less space for the median nerve, increasing the risk of compression.
- Bone and Joint Conditions: Disorders like osteoarthritis and acromegaly can alter the shape and size of the carpal bones, leading to damage of surrounding muscles, tendons, and nerves.
- Swelling and Inflammation:
- Rheumatoid Arthritis: Causes chronic inflammation of the joints, leading to swelling that can compress the median nerve.
- Repetitive Wrist Movements: Prolonged flexion or extension of the wrist (e.g., due to occupational activities) increases pressure within the carpal tunnel.
- Hormonal Changes: Menopause and pregnancy involve hormonal fluctuations that can cause fluid retention, increasing the risk of swelling around the median nerve.
Case Study:
A 41-year-old male presented to the hospital with complaints of pain and numbness in both hands. He has a known history of acromegaly, a condition characterized by the excess production of growth hormone, leading to the enlargement of bones, cartilage, soft tissues, and nerves.
In this case, acromegaly caused:
- Thickening of the carpal bones and soft tissues, narrowing the carpal tunnel.
- Enlargement of the median nerve, which impaired nerve conduction.
These changes resulted in bilateral carpal tunnel syndrome, affecting both hands.
Exercises for Carpal Tunnel Syndrome
These exercises are designed to improve wrist mobility, reduce nerve compression, and promote flexibility in the wrist and fingers. Perform them only after your acute symptoms (pain, numbness, or tingling) have subsided.
- Wrist Warm-up and Finger Stretch:
- How to Do It:
- Gently rotate your wrists in circular motions—up, down, and side to side.
- Stretch your fingers wide apart, hold for a few seconds, then relax.
- Thumb Stretch: Gently pull your thumb backward using your other hand, hold for 5–10 seconds, and release.
- Repetitions: Repeat all stretches 4 times.
- Benefit: Improves flexibility and reduces stiffness in the fingers and wrist.
- How to Do It:
- Prayer Stretch:
- How to Do It:
- Place your palms together in a prayer position in front of your chest.
- Slowly lower your hands toward your abdomen while keeping your palms pressed together.
- Hold the stretch for 15–20 seconds until you feel a gentle stretch in your forearms and wrists.
- Repetitions: Repeat 4 times.
- Benefit: Stretches the flexor muscles and relieves tension in the carpal tunnel area.
- How to Do It:
- Wrist Extension Stretch:
- How to Do It:
- Extend one arm straight in front of you with your palm facing down.
- Using your opposite hand, gently pull the fingers backwards towards your body until you feel a stretch in your forearm.
- Hold for 15 seconds, then release.
- How to Do It:
- Repetitions: Repeat 4–5 times on each hand.
- Benefit: Increases flexibility of the wrist extensor muscles and reduces pressure on the median nerve.
- Wrist Flexion Stretch:
- How to Do It:
- Extend one arm straight in front of you with the palm facing down.
- Bend your wrist downward so your fingers point towards the floor.
- Use your opposite hand to apply gentle pressure, pulling the hand toward your body until you feel a stretch.
- Hold for 15 seconds, then relax.
- Repetitions: Repeat 4–5 times on each side.
- Benefit: Stretches the wrist flexor muscles, relieving tension around the carpal tunnel.
- How to Do It:
- Median Nerve Gliding Exercise:
- How to Do It:
- Start with your wrist in a neutral position, fingers and thumb curled into a loose fist, with the thumb facing you.
- Step 1: Extend your fingers and thumb into a straight, neutral position.
- Step 2: Keeping fingers straight, bend your wrist backward so your palm faces upward.
- Step 3: While maintaining the same position, extend your thumb away from your fingers.
- Step 4: Rotate your wrist so your palm faces outward (away from you).
- Step 5: Use your free hand to gently pull the thumb downward for an added stretch.
- Repetitions: Perform 4–5 repetitions per session.
- Benefit: Promotes smooth movement of the median nerve, reducing adhesions and improving nerve function.
- How to Do It:
- Perform these exercises gently—they should cause a mild stretch, not pain.
- Stop immediately if you feel sharp pain, worsening numbness, or discomfort.
- Consult your doctor or physical therapist before starting these exercises, especially if your symptoms are severe or persistent.
Treatment for Carpal Tunnel Syndrome
Carpal Tunnel Syndrome (CTS) treatment aims to reduce pressure on the median nerve, alleviate symptoms, and restore normal hand function. Depending on the severity, your doctor may recommend non-surgical or surgical options:
- Wrist Splints
- How It Works: Wrist splints help maintain the wrist in a neutral position, especially during sleep, to reduce pressure on the median nerve.
- When It’s Used: Ideal for mild to moderate CTS, particularly when symptoms worsen at night.
- Benefit: Provides symptom relief without medication or invasive procedures.
- Anti-inflammatory Medications (NSAIDs)
- How They Work: Non-steroidal anti-inflammatory Drugs (NSAIDs), like ibuprofen, help reduce pain and inflammation in the wrist.
- Forms:
- Oral NSAIDs: For general pain and inflammation relief.
- Injections: NSAIDs can also be injected directly into the carpal tunnel for targeted reduction of swelling.
- Note: NSAIDs relieve symptoms but don’t treat the underlying cause of nerve compression.
- Corticosteroid Injections
- How They Work: Cortisone injections reduce inflammation and swelling around the median nerve, providing quick relief from pain and numbness.
- Relief may last from weeks to several months, but symptoms can return if the underlying cause isn’t addressed.
- Note: Repeated injections are generally avoided due to the risk of tendon weakening over time.
- Open Carpal Tunnel Release Surgery
- The surgeon makes a small incision in the palm to access and cut the transverse carpal ligament, relieving pressure on the median nerve.
- This is typically an outpatient procedure, meaning you can go home the same day.
- Benefit: Provides long-term relief, especially for severe cases where conservative treatments have failed.
- Endoscopic Carpal Tunnel Release Surgery
- A tiny camera (endoscope) attached to a thin tube is inserted through a small incision in the wrist. This allows the surgeon to view the ligament and release it using specialized tools.
- Advantages:
- Smaller incision compared to open surgery
- Faster recovery with less post-operative pain
- It is also performed as an outpatient procedure, with discharge on the same day.
Choosing the Right Treatment:
- Mild CTS: Wrist splints, NSAIDs, and corticosteroid injections are typically effective.
- Moderate to Severe CTS: Surgery (open or endoscopic) may be recommended if symptoms persist despite conservative treatments.
Conclusion
Carpal tunnel syndrome is a progressive condition that, if left untreated or undiagnosed, can result in permanent loss of sensation and function in the hand. Fortunately, approximately 70%-90% of cases respond well to conservative management. However, it’s important to note that recurrence can occur in up to 1/3rd of patients within 5 years even after surgical intervention. Timely diagnosis and appropriate treatment are crucial for preventing long-term complications and improving outcomes.

Mihika Lokhande, Medical Student
Reviewed by Dr Aarti Nehra (MBBS, MMST), Time: 11 am (IST)