Comparison of NA vs. HNA

Most websites on PTS limit the involvement to that of the shoulder girdle, and usually suggest there is only one attack. The differences in HNA and NA attack sites are discussed by Nens van Alfen, MD- here:

http://brain.oxfordjournals.org/cgi/content/abstract/129/2/438

“HNA patients had an earlier onset (28.4 versus 41.3 years), more attacks (mean 3.5 versus 1.5) and more frequent involvement of nerves outside the brachial plexus (55.8 versus 17.3%) than INA patients, and a more severe maximum paresis, with a subsequent poorer functional outcome.”

I have mentioned earlier on all of the potential plexus sites which can be impacted by HNA, but here is a distribution found on Gene Reviews-

http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=gene&part=hna

“While the shoulder and arm are primarily affected by attacks in HNA, other sites that may also be involved in an attack include the following:
• Lumbosacral plexus in ~33% of attacks
• Phrenic nerve palsy in 14% of attacks; may cause orthopnea, respiratory distress and sleep disturbance
• Recurrent laryngeal nerve in 3% of attacks; may cause vocal cord paresis resulting in hoarseness and hypophonia
• Facial nerve or other cranial nerves (rarely)”

While there is a genetic test to determine whether you have HNA or NA, this would seem to suggest that if you have had more than one occurrence of NA, or if you have had involvement of other plexus sites, at least statistically you may have more chance of having Hereditary Neuralgic Amyotrophy.