Written by: By Lauren McNamara PT, DPT
Virtual Hand to Shoulder Fellow '21
For years, I witnessed my mom struggle with everyday tasks or even get a good night’s sleep due to symptoms associated with carpal tunnel syndrome. She has been working for a health insurance company for more than 20 years, which requires at least 40 hours a week of typing on a computer. She always deferred surgical interventions, but was not well educated during the early stages on conservative measures. She did not receive adequate information on activity modification or maintaining ergonomic set up at work and home. During the early stages of her CTS, I was very young and not in PT school yet so I was unaware of ways to help manage symptoms, delay progression, and to avoid onset of CTS. I would like to help others minimize symptoms and delay progression of CTS with education on how to maintain a good work set up, ergonomic changes at home, as well as task modifications.
There are various factors that contribute to developing carpal tunnel syndrome, such as: systemic inflammatory diseases, use of vibrating tools at work, fluid during pregnancy, or repetitive wrist/hand movement . When the space diminishes due to inflammation of the tendons, for example, it puts compression on the median nerve. This compression can result in pain, paresthesias, as well as weakness. Ergonomic set up at work and home is a component of conservative management of CTS. For desk jobs requiring computer work or in construction related work requiring the use of tools, maintaining the wrist in a neutral position optimizes the carpal tunnel space for the nerve. Therefore, at a desk job it might be beneficial to purchase an ergonomic keyboard, and in construction, using tools that have handles appropriately angled help maintain a neutral wrist position. Other suggestions include to not use a keyboard with a stand that elevates the wrists back into extension, or rest your arms on the keyboard which would cause wrist flexion and add an external compression to the carpal tunnel. When using a mouse at a computer, make sure that the mouse is appropriate for the size of your hand. If it’s too large it could cause excessive gripping and if too small can cause excessive pinching. Ergonomic mouses can also be purchased, which maintain the wrist and hand in a neutral position. Sitting in an upright posture with the forearms parallel to floor, elbows at one’s sides, and positioning the computer screen to help maintain neutral spine is important not only for preventing CTS but other musculoskeletal conditions.
In addition to ergonomics, wrist immobilization is another conservative option, with the main purpose to maintain the wrist in a neutral position. This position places the wrist with the least amount of internal pressure in the carpal tunnel, minimizes inflammation by reducing nerve and tendon movement through the tunnel, and decreases the contents of tunnel by positioning the wrist to bring the lumbrical muscle origins distally and retract extrinsic flexors proximally. The orthosis is most effective when initiated within 3 months of symptom onset. Studies show that for a custom versus a prefabricated orthosis at night, the prefabricated orthoses do not limit wrist motion to neutral or block the digits from full flexion, indicating that a custom orthosis would be a better option. Night time wear is emphasized to prevent excessive flexion while sleeping. Occasionally a separate daytime orthosis may be needed to limit movement but still allow ability to complete ADL’s.
Studies have also shown that people have seen improvement of symptoms with tendon gliding exercises in conjunction with other forms of conservative management. Completing these exercises improve tendon mobility through the carpal tunnel. It is important to keep in mind that research continues to gather information on how conservative options reduce inflammation, decrease pressure in the carpal tunnel, and increase the space in the tunnel to allow improved nerve conduction. The strongest evidence available supports the use of an orthosis and activity modification. Overall, more research is still needed to determine if ergonomic set up at work, such as computer and keyboard configuration, influences the development or progression of CTS. It is still advised to make these recommendations to those at risk for developing CTS and to avoid positions or activities that exacerbate their symptoms.
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Standard of Care: Carpal Tunnel Syndrome. The Brigham and Women’s Hospital, Inc. Department of R