Carpal tunnel syndrome

Disease Description (Causes and Symptoms)

• Definition: A syndrome in which the median nerve passing through the carpal tunnel (wrist tunnel) is compressed, causing sensory abnormalities and motor impairment (carpal tunnel syndrome).
• Causes/pathophysiology: Compression of the median nerve due to a decrease in the cross-sectional area of the carpal tunnel or increased internal pressure (such as tendon sheath inflammation, swelling, or compression of the transverse carpal ligament) → sensory abnormalities (occurring first), followed in severe cases by atrophy and decreased strength of the thenar muscles.
• Major risk factors: Middle-aged women, obesity, diabetes, pregnancy (temporary), chronic kidney failure (dialysis), rheumatoid arthritis, and repetitive or excessive wrist use (e.g., hairdressers, computer work).
• Major symptoms:
  • Numbness in the thumb, index finger, middle finger, and part of the ring finger (excluding the little finger)
  • Numbness that worsens at night and wakes the person from sleep
  • Frequently dropping objects and decreased hand strength
  • Pain in the palm and wrist, with possible radiating pain to the arm, shoulder, or neck
  • As the condition progresses, atrophy of the thenar muscles, which form the bulge at the base of the thumb

Treatment Methods

• Nonsurgical (early or mild cases, or when there is no muscle atrophy):
  • Use of a nighttime wrist splint (holding the wrist in a neutral position)
  • Modification of activities and work habits (taking frequent breaks, maintaining a neutral wrist position, improving workplace ergonomics)
  • Medication: Anti-inflammatory analgesics (limited to symptom relief)
  • Local steroid injection (injection into the carpal tunnel/ultrasound-guided injection): May provide temporary symptom improvement
  • Physical therapy and nerve-gliding exercises (helpful in some people)
• Surgical:
  • Decompression of the median nerve by cutting the transverse carpal ligament (surgical carpal tunnel decompression)
  • Methods: Open carpal tunnel release or arthroscopic/endoscopic surgery (through a small incision)
  • Indications: Failure of conservative treatment, impairment of daily activities, progressive deterioration of nerve or motor function, acute symptoms, etc.
• Precautions and complications:
  • If early treatment is delayed, muscle atrophy may be irreversible
  • Surgical complications: Infection, bleeding, scar pain (pillar pain), nerve injury (rare), and possible recurrence
  • Side effects of steroid injections: Temporary elevation of blood glucose (caution in patients with diabetes) and possible increased risk of infection
• Prognosis:
  • Pain and numbness often improve rapidly after surgery; recovery of motor function (strength) takes several weeks to several months
  • Complete recovery may be difficult in cases of chronic, severe muscle atrophy
  • Overall, many patients experience symptom improvement and have high satisfaction

Checklist Before an Outpatient Visit (Preparation and Tests — Including Example Questions)

• Items/documents to bring:
  • List of currently used medications (including dosages) and allergy information
  • Copies of previous test results (electromyography/nerve conduction studies, wrist X-rays, ultrasound, etc.)
  • Symptom record (when symptoms started, number of nighttime awakenings, frequency of dropping objects, whether weakness is present)
  • Information about occupation and work habits (whether there is repetitive wrist use) and wrist position during sleep
  • Relevant underlying conditions (diabetes, thyroid disease, rheumatoid arthritis, kidney failure, pregnancy, etc.)
• Things that are helpful to show the doctor during the outpatient visit:
  • Notes recording the timing and pattern of symptoms (e.g., how severe the numbness is if it occurs only at night)
  • Photos of the hand (if thenar atrophy is suspected)
• Possible tests (items the doctor may recommend):
  • Neurological examination (sensory and strength testing, Tinel sign, arm flexion test (Phalen test))
  • Electrodiagnostic testing (nerve conduction study, electromyography) — for diagnosis and assessment of severity
  • If necessary, radiography (to differentiate cervical spine problems) and ultrasound (to evaluate findings of nerve compression)

Examples of General Questions to Ask the Doctor

• "What causes this condition, and which factors had the greatest influence in my case?"
• "What nonsurgical treatments can you recommend for my current symptoms, and how effective are they?"
• "What side effects can occur if I receive a steroid injection, and how should it be managed if I have diabetes?"
• "If you recommend surgery, how long will recovery take, and when can I return to daily activities?"
• "What lifestyle changes should I make to reduce the risk of recurrence and prevent it?"

Examples of Condition-Specific Questions

• "My electrodiagnostic (nerve conduction) results show mild delay. Is surgery necessary at this stage?"
• "My job involves a lot of repetitive wrist use. What postural or tool changes do you recommend during work?"