Most people with carpal tunnel symptoms think the source of their problem is located in the wrist. While the wrist and hand may be the site of most of your symptoms, the real cause or causes can reside elsewhere along the course of the median nerve, even in the neck. For example, a disk injury or cervical joint dysfunction in your neck could interfere with the function of the median nerve as it passes through the neck towards your shoulder, arm, wrist, and fingers. When this occurs and there is also a problem with compression at the wrist, it is called a double-crush syndrome.
A 2007 study (Clin Neurol Neurosurg 2007; Oct.11; Moghaderi A, Izadi S) that included 142 patients with carpal tunnel syndrome (CTS) and 109 controls/normal patients looked into risk factors associated with double crush syndrome. One hundred six patients had pure carpal tunnel syndrome and 36 patients had double-crush injuries. The researchers specifically investigated age, gender, and body mass index as independent risk factors for the condition.
Because aging can have an influence on degeneration of the disks in the neck—which can lead to narrowing of the passages the nerves must course through as they exit the spinal cord and move down the arm—it's no surprise that older age was associated with a greater risk of double-crush syndrome. Interestingly, the results also showed that men are more likely to have double-crush syndrome than women.
Based on these findings, the authors of the study recommend that doctors check for nerve dysfunction of the neck in all older men who present with carpal tunnel symptoms.
