Model Answer
0 min readIntroduction
Carpal Tunnel Syndrome (CTS) is a common entrapment neuropathy affecting the median nerve as it passes through the carpal tunnel in the wrist. Characterized by pain, numbness, tingling, and weakness in the hand and fingers, CTS significantly impacts daily activities and quality of life. The prevalence of CTS is increasing, likely due to repetitive strain injuries associated with modern work and lifestyle. Understanding its pathophysiology, clinical presentation, and etiology is crucial for effective diagnosis and management. This answer will detail the manifestations and causes of Carpal Tunnel Syndrome.
Understanding Carpal Tunnel Syndrome
The carpal tunnel is a narrow passageway on the palmar side of the wrist formed by the carpal bones and the transverse carpal ligament. Within this tunnel lie the median nerve, along with tendons that flex the fingers. Compression of the median nerve within this space leads to CTS.
Manifestations of Carpal Tunnel Syndrome
The symptoms of CTS typically develop gradually and can vary in severity. They often begin insidiously and may be intermittent initially.
- Sensory Symptoms: These are the earliest and most common symptoms. They include:
- Numbness and tingling in the thumb, index, middle, and radial half of the ring finger.
- Pain radiating up the forearm.
- Burning sensation in the hand.
- Increased symptoms at night, often disrupting sleep.
- Motor Symptoms: As the condition progresses, motor weakness may develop.
- Weakness in the thenar muscles (muscles at the base of the thumb), leading to difficulty with grip strength and fine motor movements.
- Clumsiness and dropping objects.
- Atrophy of the thenar muscles in severe, long-standing cases.
- Vascular Symptoms: Some patients report changes in hand temperature, color, and swelling, though these are less common.
Causes of Carpal Tunnel Syndrome
The causes of CTS are multifactorial, often involving a combination of predisposing factors and aggravating influences. These can be broadly categorized into intrinsic and extrinsic causes.
Intrinsic Causes (Factors within the individual)
- Anatomy: A smaller carpal tunnel, inherited anatomical variations, or wrist fractures can predispose individuals to CTS.
- Age: The risk of CTS increases with age, potentially due to age-related changes in the tendons and ligaments.
- Sex: Women are more likely to develop CTS than men, possibly due to a smaller carpal tunnel and hormonal influences.
- Medical Conditions: Certain medical conditions are associated with an increased risk of CTS:
- Diabetes: Diabetic neuropathy can affect the median nerve.
- Hypothyroidism: Can cause fluid retention and nerve compression.
- Rheumatoid Arthritis: Inflammation can narrow the carpal tunnel.
- Pregnancy: Hormonal changes and fluid retention during pregnancy can contribute to CTS.
- Obesity: Increased body mass index is associated with a higher risk.
- Genetic Predisposition: Family history of CTS can increase susceptibility.
Extrinsic Causes (Factors related to activities and environment)
- Repetitive Hand Movements: Activities involving repetitive wrist flexion, extension, or vibration can contribute to CTS. Examples include:
- Assembly line work
- Typing
- Using hand tools
- Playing musical instruments
- Forceful Gripping: Jobs requiring forceful gripping or prolonged use of vibrating tools.
- Wrist Position: Maintaining the wrist in an awkward position for extended periods.
- Trauma: Wrist fractures or dislocations can damage the carpal tunnel.
Diagnosis
Diagnosis typically involves a combination of clinical evaluation, physical examination, and electrodiagnostic studies.
- Tinel's Sign: Tapping over the median nerve at the wrist elicits tingling.
- Phalen's Test: Holding the wrists in full flexion for 60 seconds reproduces symptoms.
- Nerve Conduction Studies (NCS): Measures the speed of electrical signals along the median nerve.
- Electromyography (EMG): Assesses the electrical activity of muscles controlled by the median nerve.
Conclusion
Carpal Tunnel Syndrome is a prevalent condition resulting from median nerve compression, manifesting as sensory and motor deficits in the hand. Its etiology is complex, involving both intrinsic and extrinsic factors. Early diagnosis through clinical evaluation and electrodiagnostic studies is crucial for initiating appropriate treatment, ranging from conservative measures like splinting and activity modification to surgical intervention in severe cases. Preventive strategies focusing on ergonomic principles and addressing underlying medical conditions are essential for reducing the incidence of CTS.
Answer Length
This is a comprehensive model answer for learning purposes and may exceed the word limit. In the exam, always adhere to the prescribed word count.