A 46-year-old dental hygienist presents to the clinic with a 6-month history of numbness and a sensation of pins and needles in her right hand. She notes that the symptoms are most severe at night and often require her to shake out her hand for relief. Past medical history is negative. On physical examination, there is mild atrophy of the thenar eminence. Sensation to pinprick is decreased over the palmar aspect of the thumb, index, and middle fingers, but is preserved over the central palm. Tapping over the volar aspect of the wrist reproduces the tingling sensation in the affected digits.
Which of the following is the most appropriate initial step in the management of this patient?
The correct answer is:
C) Neutral-angle nocturnal wrist splinting
The patient is presenting with carpal tunnel syndrome (CTS), the most common entrapment neuropathy, caused by compression of the median nerve as it passes through the carpal tunnel. The diagnosis is supported by her occupation which involves repetitive wrist motion, nocturnal symptoms, thenar atrophy, and a positive Tinel sign (tingling upon percussion of the nerve). A key anatomical landmark is that the palmar cutaneous branch of the median nerve branches off proximal to the carpal tunnel. Therefore, sensation to the central palm is typically spared in CTS, helping to localize the compression specifically to the tunnel. For patients with mild to moderate symptoms, conservative management is the first-line approach. Neutral-angle nocturnal wrist splinting is the most appropriate initial step. Splinting at night prevents the wrist from flexing or extending, which minimizes the pressure within the carpal tunnel and allows for the reduction of local edema.
Answer choice A: Arthroscopic flexor tenosynovectomy, is incorrect. While inflammation of the flexor tendons can contribute to CTS, a tenosynovectomy is not a standard first-line treatment and is generally reserved for specific inflammatory conditions like rheumatoid arthritis.
Answer choice B: Corticosteroid injection, is incorrect. While carpal tunnel injection is effective for temporary relief of symptoms, it is typically considered second-line after a trial of splinting and activity modification has failed.
Answer choice D: Oral prednisone taper, is incorrect. Systemic steroids are generally not recommended for the treatment of localized CTS due to their side-effect profile and the superior efficacy of localized treatments like splinting or local injections.
Answer choice E: Surgical decompression, is incorrect. Surgical release of the transverse carpal ligament is the definitive treatment for CTS. However, it is usually indicated only after conservative measures have failed, or in patients with severe disease characterized by significant motor weakness or profound thenar atrophy.
Key Learning Point
The initial management of mild-to-moderate carpal tunnel syndrome consists of nocturnal wrist splinting in a neutral position and activity modification. If symptoms persist or if there is evidence of severe nerve compromise such as thenar atrophy or persistent weakness, surgical decompression of the transverse carpal ligament is indicated.
