CARPAL TUNNEL SYNDROME

CLICK HERE TO SEE IF YOU SUFFER FROM CARPAL TUNNEL SYNDROME BY TAKING THE CARPAL TUNNEL QUIZ 

WHAT IS CARPAL TUNNEL SYNDROME?

Physicians define carpal tunnel syndrome as a compression neuropathy of the median nerve. Compression neuropathy means that compression has made the nerve (‘neuro’) sick (‘pathy’). Inside the carpal (wrist) tunnel lies a tight space bordered by bones on three sides and the tight carpal tunnel ligament holding everything down like a tight belt on top. The contents of the carpal tunnel include the flexor tendons to the fingers and the median nerve. The median nerve provides sensation to the thumb, index and middle finger and motor function to the thumb. Compression of this nerve will cause numbness, tingling and pain in the thumb, index and middle fingers, and eventually will lead to weakness of the thumb muscles. Carpal tunnel syndrome exists as the most common peripheral compression neuropathy, accounting for 90% of peripheral cases. Experts estimate that 5% of the US population suffers from carpal tunnel syndrome.1

WHAT CAUSES CARPAL TUNNEL SYNDROME?

The most common cause of carpal tunnel syndrome is ‘idiopathic’- meaning that we do not know what exactly causes it. Carpal tunnel syndrome likely occurs from a combination of events. Risk factors for carpal tunnel syndrome include:

  • Demographics: female sex, older age
  • Health conditions: pregnancy, diabetes, thyroid disease, rheumatoid arthritis
  • Hand and wrist position: activities that hold the hand in the extremes of flexion or extension can increase pressure on the median nerve
  • Repetitive hand use: overuse of the flexor tendons running through the carpal tunnel can lead to inflammation and swelling of the tendons, leaving less space for the median nerve and contributing to its compression
  • Heredity: inherited anatomic differences likely play a role in development of carpal tunnel syndrome 

WHAT ARE SYMPTOMS OF CARPAL TUNNEL?

People experience symptoms of carpal tunnel syndrome differently, but the most common symptoms include numbness/tingling, electric shocks, burning, or pain of the thumb, index and middle fingers. Often people with carpal tunnel will complain of dropping objects and waking up in the middle of the night and can lose 2.5 hours of sleep per night.2 Severe carpal tunnel will present with weakness of the thumb and difficulty getting the thumb out of the palm of the hand, such as when one tries to grasp around a cup.

DIAGNOSIS AND TREATMENT

DIAGNOSIS OF CARPAL TUNNEL SYNDROME

Physicians can often diagnose carpal tunnel syndrome by confirming the symptoms and by performing a clinical examination including provocative physical examination tests to reproduce the symptoms. Patients may undergo US (ultrasound) studies in our office to examine the median nerve as it enters the carpal tunnel as well. At times Doctors require EMG (electromyography) and NCS (nerve conduction studies) to measure nerve conduction velocities to determine where and how the compression lies. Besides compressing the carpal tunnel, in rare cases it may compress the neck and the forearm as well. PM&R or neurology doctors can perform EMG/NCS, an invasive study that involves placing small needles the size of acupuncture needles in the forearm and hand and giving small electric shocks to determine nerve function and speed.

TREATMENT OF CARPAL TUNNEL SYNDROME

Treatment of carpal tunnel syndrome includes conservative non-operative treatment options and surgical options. Non-operative treatment may benefit mild carpal tunnel syndrome, but usually offers only temporary relief in moderate and severe carpal tunnel syndrome for which doctors recommend surgical release as definitive treatment. 

  • Lifestyle modifications: decreasing repetitive hand and wrist movements and modifying activities to decrease extremes of wrist flexion and extension for long periods of time.
  • Wrist cock-up brace: will hold the wrist in 20 degrees extension to create the most area within the carpal tunnel.
  • NSAID medications: found to be equivalent to placebo for carpal tunnel treatment in scientific trials, but some patients may benefit from their use.
  • Physical therapy: stretches and nerve gliding exercises can help mild carpal tunnel syndrome. The AAOS offers a recommended program that you can try at home: https://orthoinfo.aaos.org/globalassets/pdfs/a00789_therapeutic-exercise-program-for-carpal-tunnel_final.pdf
  • Cortisone injections: can confirm the diagnosis in equivocal cases and correlate with successful symptom resolution after a surgical release.
  • Endoscopic carpal tunnel release: a minimally invasive release of the carpal tunnel ligament performed with an endoscopy camera the size of a small pen, inserted through a small incision at the wrist crease. 
  • Open carpal tunnel release: a classic surgical release with an incision made in the palm over the carpal tunnel ligament. 

FURTHER READING

AAOS – American Academy of Orthopaedic Surgeons carpal tunnel syndrome OrthoInfo webpage. https://orthoinfo.aaos.org/en/diseases–conditions/carpal-tunnel-syndrome/

ASSH- American Society of Hand Surgery carpal tunnel syndrome Handcare webpage. https://www.assh.org/handcare/condition/carpal-tunnel-syndrome

REFERENCES

  1. “Carpal tunnel syndrome” by Kyle Bickel published in the Journal of Hand Surgery Jan 2010. https://pubmed.ncbi.nlm.nih.gov/20117319/
  2. “The negative effect of carpal tunnel syndrome on sleep quality” by Ashish Patel et al published in the Journal of Sleep Disorders Feb 2014. https://pubmed.ncbi.nlm.nih.gov/24693441/
  3. “A clinical questionnaire for the diagnosis of carpal tunnel syndrome” by Kamath and Stothard published in the Journal of Hand Surgery: British and European Volume Oct 2003. https://pubmed.ncbi.nlm.nih.gov/12954256/