My son is on an extended hike of over 2600 miles,

Wow, that is quite a hike. Is it the Adirondack trail, just out of curiosity? What an achievement, in any case.

I think you might indeed be on the right track. If he is experiencing numbness in both of his hands, without any other symptoms at all, then this could be related to his pack, which I'm sure is quite large and heavy. Although, today, modern packs are designed to be as ergonomic as possible, hikes like this will inevitably end up putting a considerable strain on the body. The straps can put pressure on the nerves that end up supplying the hands.

I think that the hiking poles might also be involved, if he is using them constantly, but more likely he is only using them occasionally, and as such, I think that the pack is a more likely culprit.

Hopefully, at night when he is resting without his pack/poles his symptoms resolve. If so, then I don't think that he is necessarily at any increased risk for any future problems. If the numbness resolves each night, then when the hike is done, it should also resolve.

I hope this helps. Please let me know if you have any further questions - I'm more than happy to help.

Take care - Dr. Fay

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Actually it is the Pacific Crest Trail, which is longer than the AT, it is 2658 miles, from the border of Mexico at Campo to Manning Park, BC, Canada. I am very proud of him, as I am my other 2 sons. He does use the trekking poles constantly as well, he has extreme elevation gains, in this stretch last 400 miles it goes up and down 3 or 4 times a day, with 2k to 4k increases and decreases.This is after going through the desert and the High Sierras of California ( his highest was 13,000 ft), and all through the state of Oregon, and now 1/3 of the way through Washington. I was pretty sure that it was due to the pack sometimes 40 lbs. at new resupply stops, and the constant use of the poles. Even though as you stated they are designed better now the body can only take so much, he started May 19, 06 and has Oct.9, 06 as his completion date. Thank you for your quick reply. Kind regards, Rena