Good day, and thank you for using Ask an Expert.  Your question is a tough one to answer because top growth can be affected by several things, among them root rot, some insects, herbicides and more.   

Pictures are likely to be of considerable help. So when you reply to me, please attach 3 images.  Preferred views are these:
1. An overall of the portion of the planting that has the problem.
2. A view of one of the typical affected plants.
3. Another close up, this of just one affected cane showing both healthy and affected areas.  

Just in case it might be helpful, this link is for “Growing Raspberries in Your Home Garden” http://ir.library.oregonstate.edu/xmlui/bitstream/handle/1957/18936/ec1306.pdf  

I look forward to receiving your pictures in hopes that we can resolve your problem.

Here are a couple photos

Thank you for sending the images.   

The close-up view shows two different arching canes.  When I look at the lower cane of the two, I see some upright side shoots.  If the rather crumpled leaves toward the left are lower on the cane than the very upright shoot near the center of the image, I think that the cane is returning to a normal growth pattern.  So,I suspect herbicide (weed killer) damage.  

But when I look at the overall image, I see many grasses and some broadleaf weeds.  So I  need to ask if herbicide was used somewhere, anywhere, in the general area?  Even if herbicide wasn’t used along the row, it could have drifted there on a breeze or on spray turbulence.  If you didn’t use herbicide, do you have a garden helper or neighbor who wanted to do you a favor?  

Please let me know if any of that theory makes sense to you. 

Thanks for your thoughts Jean.   I have never uses a herbicide in my yard and have lived here almost 20 years.   My teenage son and I are the only ones who work in the yard.   
So, I gave the thought of herbicide drift from a neighbor who hires out his yard work.  I know that they use chemicals on the yard as I have seen them applying it.   The plants closest to my neighbor are fine.   It is possible.   So much for organic - rats! 

In the past couple of years, several of my canes had deformed leaves - very crumpled looking.  I don't recall if they had fruit or not.   
I did introduce a couple new canes last year.   I bought them from Portland Nursery but don't remember the variety.   Those new ones are all included in the problem.   

Do you have any other ideas?

Hello again.  Thank you for getting back to me so promptly.   

These are my thoughts at this time:
- If this is herbicide damage, then the plants will outgrow the problem. 
- Some virus diseases can “crinkle” leaves.  In many instances, leaves also have some yellow discoloration.   If the problem is due to a virus disease, the damaged leaves won’t return to normal.  

Let’s return to my question about the close-up image: Is the lower part of the cane toward the left, the upper part toward the right?  If so, the cane is now growing normally which points toward herbicide damage.

Oh yes, a question about those newer plants: You said they are all affected.  Are they the only ones that are affected?   

A word about your efforts to have an organic garden:  Take heart because, if the problem is due to herbicide, the product will degrade normally in relatively short order and you can again feel secure about the food you’re growing.  

You asked:
Is the lower part of the cane toward the left, the upper part toward the right? If so, the cane is now growing normally which points toward herbicide damage.
In both canes in the close up photo the top of the cane is to the right and the bottom of the cane is to the left.   Most of the canes look like the top one - no new growth or very stunted growth from the start and hasn't changed. 

You asked:
Oh yes, a question about those newer plants: You said they are all affected. Are they the only ones that are affected? 
Not only the new ones are affected.   I have have 5 rows of canes, each about 12-15 feet.   Of those about 1/2 are affected.   

Thank you for your responses.  I plan to consult w/ another Expert in hopes of resolving the problems with your raspberries. 

In the meantime, email me if you recall anything else you think might assist with a diagnosis.

Hello, again.  My colleague reviewed your information and sent these comments:  

“The symptoms are too regular to be herbicide or pest. If only last year’s canes are affected then that raises the question: Are these summer bearers or primocane fruiters? The tip is supposed to be dead on primocane fruiters – doubt it’s that easy but it’s worth a try. Is the yard in shade?  

“My guess is that the buds at the top of the cane are dead – no disease will do this – it has to be physiological or environmental – that’s assuming the symptoms are rather regular.”  

Do you know the variety of raspberries?  That would explain if they are summer bearers or primocane fruiters.

Hope that provides you with some answers.