Most bamboo plants (including the black nigra bamboo)love cow or horse manure, or any fertilizer high in Nitrogen is good. They need to be planted in well draining soil (don't like boggy soil) and require lots of water as they originate from areas that have high rainfall....monsoons. I would try soaking the soil and watering often to revive the bamboo roots and hopefully it will shoot again. Good luck!

P.S.( In Winter they do normally loose lots of leaves anyhow...but just make sure the soil is not bone dry)

Sunrose is correct, bamboo lose leaves in winter to make way for new shoots.

A spikey bit? It's not flowered has it? These look like small clumps of spikes, rather like grass type flowers, but not as noticeable or attractive, and if its flowered, it'll probably die, they usually do, but the advice is to cut it right down, when you might get regrowth. If you're not sure, posting a photo on here would be helpful.

Thanks for all the answers. I think the bamboo properly need water and feeding, which I will try. Thanks everyone.