Carpal Tunnel Syndrome (CTS) is caused by compression of a nerve at the wrist (median nerve). A tunnel is formed by the bones of the wrist and a sheet of tissue over top. The median nerve travels through this tunnel. The nerve can be compressed in this tunnel for numerous reasons. CTS is very common.
Very occasionally (7-10%) of the time the median nerve can be compressed in other areas further up in the forearm. The term “proximal median nerve entrapment” (PMNE) includes all the other areas in the forearm where the median nerve can get compressed. This is where things get confusing.
In summary, the most common area for the median nerve to be compressed is at the wrist, followed occasionally by compression in tissues near the elbow. It is important to note that there are other things that may be going on that can complicate the picture like: neck problems, hypersensitive nervous system, hormonal issues etc.
If you think you may have nerve compression in your arms, please see a qualified medical professional, such as a registered physiotherapist, who can help you sort it out.
References:
Adler JA, Wolf JM. Proximal Median Nerve Compression: Pronator Syndrome. J Hand Surg Am. 2020 Dec;45(12):1157-1165.
Hagert E. Clinical diagnosis and wide-awake surgical treatment of proximal median nerve entrapment at the elbow: a prospective study. Hand (N Y). 2013, 8: 41–6.
Marcus R Bair, Michael T Gross, Jennifer R Cooke, Carla H Hill. Differential Diagnosis and Intervention of Proximal Median Nerve Entrapment: A Resident's Case Problem. J Orthop Sports Phys Ther . 2016 Sep;46(9):800-8
Mia Erickson, Marsha Lawrence, Caroline W Stegink Jansen, Diane Coker, Peter Amadio, Carla Clear. Hand Pain and Sensory Deficits: Carpal Tunnel Syndrome. J Orthop Sports Phys Ther . 2019 May;49(5): CPG1-CPG85.
Tang JB. Median nerve compression: lacertus syndrome versus superficialis-pronator syndrome. J Hand Surg Eur. 2021, 46: 1017-22