Aetiology of Carpal Tunnel Syndrome Carpal tunnel syndrome (CTS) is a common condition caused by compression of the median nerve as it travels through the carpal tunnel in the wrist. Several factors contribute to the development of CTS: Anatomy of the Carpal Tunnel The carpal tunnel is a narrow passageway formed by bones and ligaments in the wrist. It houses the median nerve and flexor tendons that control finger movements. Aetiological Factors 1. Compression of the Median Nerve: Pressure on the median nerve can occur due to: o Repetitive Hand and Wrist Movements: Such as typing, assembly line work, or using vibrating tools. o Prolonged or Forceful Hand Use: Activities that require bending or twisting of the wrist. o Wrist Trauma or Fractures: Injuries that cause swelling or deformity within the carpal tunnel. o Anatomical Variations: Narrowing of the carpal tunnel or variations in the anatomy that predispose to nerve compression. o Fluid Retention: Conditions like pregnancy, obesity, or hormonal changes that lead to fluid retention and increased pressure within the carpal tunnel. 2. Underlying Health Conditions: Certain medical conditions increase the risk of developing CTS: o Diabetes: Associated with nerve damage (neuropathy) that can affect the median nerve. o Rheumatoid Arthritis: Inflammatory changes within the wrist joint and synovium. o Thyroid Disorders: Hormonal imbalances affecting tissues within the carpal tunnel. Investigation of Carpal Tunnel Syndrome Clinical Evaluation 1. Symptoms: Numbness, tingling (paresthesias), and pain in the thumb, index, and middle fingers, often worse at night. 2. Physical Examination: Assessing for weakness, sensory deficits, Tinel's sign (tingling with percussion over the median nerve), and Phalen's maneuver (reproducing symptoms with wrist flexion). Diagnostic Tests 1. Nerve Conduction Studies: Measure the speed and amplitude of electrical signals along nerves, confirming median nerve dysfunction. 2. Electromyography (EMG): Assesses muscle response to nerve stimulation, identifying damage to the median nerve and ruling out other conditions. 3. Imaging: X-rays to assess for fractures or arthritis. MRI or ultrasound may show anatomical abnormalities or soft tissue changes. Principles of Management Non-Surgical Management 1. Activity Modification: Avoiding repetitive or forceful hand movements. 2. Splinting: Wearing a wrist splint at night to keep the wrist in a neutral position and alleviate pressure on the median nerve. 3. Medications: Nonsteroidal anti-inflammatory drugs (NSAIDs) or corticosteroid injections to reduce inflammation and relieve symptoms. 4. Physical Therapy: Exercises to strengthen muscles and improve wrist flexibility. Surgical Management 1. Indications: Persistent symptoms despite conservative measures, or severe cases with muscle weakness or nerve damage. 2. Procedure (Carpal Tunnel Release): o Open Surgery: Cutting the ligament to relieve pressure on the median nerve. o Endoscopic Surgery: Minimally invasive procedure using a small camera and instruments to release the carpal ligament. 3. Recovery: Typically allows for rapid relief of symptoms and restoration of hand function with minimal postoperative rehabilitation. Prognosis • • • Early Diagnosis: Leads to better outcomes with conservative management. Surgical Intervention: High success rates in alleviating symptoms and preventing nerve damage progression. Long-Term Management: Regular monitoring and preventive measures to manage underlying risk factors. Conclusion Understanding the aetiology of carpal tunnel syndrome involves recognizing factors that contribute to median nerve compression within the wrist. Effective investigation through clinical evaluation and diagnostic tests guides appropriate management strategies, ranging from conservative measures to surgical intervention when necessary. Early diagnosis and treatment are crucial in preventing complications and optimizing outcomes for individuals affected by carpal tunnel syndrome.