Not that I don't think this is great, but this isn't anything new. My Dad works in this same line of work (FES - Functional Electrical Stimulation. Particularly in the area of spinal cord injuries). The biggest thing to note from this article: "... involves surgically implanting a stimulator and giving it directions with an external remote control. ". This is amazing tech, but it's not new by any means, it's been around for a fairly long time and it's been known you can stimulate nerves via electrical stimulation. My Dad as at least a few patients that I know of that have implants for moving their arms and hands, which they've had for at least 5 or so years now (I think one of them is 10 years old, and that was a few years ago).
Now, there is something that does seem to be a bigger breakthrough in this article, specifically the notation of having on-demand function without requiring some type of remote or etc. via a stimulator. This is new as far as I know, from the basics that I know this sounds more like helping a partial spinal cord injury rather then a full injury (My Dad works with full-spinal-cord injury patients only). I'm going to send this over to my Dad and see if he has anything to say on it.
This is a bit different than what your Dad has been doing: here, an electrical stimulation allows the patient to consciously move the appendage (or engage in sexual activity). In your Dad's patients, a box is sending electrical signals to appendages to get them to move. iiuc
While you're right, they definitely talked about doing simple stimulation via a control in the article (They mention they had people lined up to do that in the article - I do recognize that's different then the headline.)
I'm guessing this patient has more of a partial spinal cord injury (So the spinal cord itself was still intact). Stimulation may have then allowed weaker signals to make it all the way though. This is definitely a big deal, but it won't work for every patient. One of the biggest challenges in the area of brain-controlled movement is that brains are so unique to everybody, and stimulating the spinal-cord directly is hard to do without accidentally stimulating other parts of the body (In general, stimulators are past the spinal cord and closer to the appendage they're going to move. Implants for the hand are usually located in the shoulder, and stimulate the nerve going off of the spinal-cord for example). If someone has a completely severed spinal cord, this technique won't make a bridge for the signal so it's not going to be a fix-all type of thing (Though, I'd be happy to be wrong!).
Can you fill us in on what this actually means? "Stimulating" a nerve doesn't imply that you're bridging a severed connection or returning control to a higher center.
In some respects I don't know, as part of this tech is new (The part which allows voluntary movement). I have a feeling the patient only had a partial spinal cord injury (Though, usually with partials there is some movement retained). In a partial, the nerves themselves aren't severed, so it would then seem like the stimulation allowed the normal nerve impulses to travel over the part which was damaged and make it down to the nerve.
Either way, 'stimulating' a nerve means applying an electric current to it to simulate a brain-signal. It's not as complicated as it sounds, it's not much more then sticking an electrode around the nerve and then applying an AC or DC current (Though AC and DC do actually produce slightly different effects). I've had it done to my hand before (Via some simple surface electrodes), depending on the placement and nerves which receive the current different muscles start pulling. If you stimulate the correct nerves, you can have the correct muscles pull and create Ex. a fist, or a clenching motion. Implants right now don't do a ton more then a simple 'open-close' type motion for a hand (Since the intent is not so you can type on a computer, but so you can eat by yourself or pick-up a glass, etc.)
spinal cord injuries are basically an electrical impedance (resistance) problem.
FES works on different levels. For one, many FES systems cycle electricity to various muscle groups in a coordinated fashion to try to get the patients body to 'take over'.
Examples of this would be with electrodes on the glutes, thighs, and around the knees in an effort to get an incomplete spinal cord patient to stand. This exploits the patients natural spasticity, along with the physiology of the body (joints can only go so many ways) to get the patient able to stand with parallel bars or in some other controlled manner.
Nerve stimulation also supposedly reduces the 'trigger energy' of certain muscle sets, thus sidestepping the impedance problem. An overly simplistic example : imagine a knee muscle requires 1mW to trigger into an action, however the circuit leading to this nerve only allows for half of that due to damage adding resistance along the pathway. FES can artificially increase the energy available to that muscle set so that the trigger may be more properly interpreted, hopefully leading to a successful 'firing' of the muscle.
source: i'm a quadriplegic, and FES makes me spasm into a 'stiff as a board' plank.
I think that is the amazing part here. It seems the researcher was doing the same type of work, implanting stimulators to study nerve function below the injury. Something in this case however is allowing on-demand capabilities and that is a mystery.
I would agree. My best guess is that they have a partial injury, so the stimulation allows the action potential to travel past the damaged part of the nerve. The article didn't really say though. They did say he had no movement past the waist, which is more of an indication of a full injury, so I'm not really sure.
A spinal cord stimulator was suggested to me several years ago to help treat the neuropathic pain [1] associated with my (complete) spinal cord injury. I'm currently trialing Prialt [2] for this, but if it doesn't work (or the side-effects are too nasty) I might pursue the stimulator.
Funny enough, spinal cord stimulation for treating chronic pain is something my Dad has been working on/researching. Unfortunately I don't know the completely status of it or what product's have been out, I do however know that it does work (I worked for my Dad for a summer internship and witnessed it first-hand), and that you need to be careful when diving into them. The side-effects vary depending on the type of stimulation (AC or DC) as well the frequency used, but they can result in nerve damage.
Specifically, it's known (At least, it was known among the group I worked with, and I saw this result happen) that extended use of the DC block will damage the nerve (On higher frequencies - IIRC 40hz was the highest we tested). AC doesn't have that issue, but AC has the issue that it actually sends a fairly large signal back up the nerve when it's turned on (So you feel a sharp pain when you turn it on). I couldn't tell you how bad it is since I've never felt it, but obviously it's still useable if Ex. you just turn it on to go to sleep at night.
Now, something unfortunate I feel obligated to tell you is that not to long ago my Dad traveled to go give a talk at a conference relating to a company that's been marketing a pain-relief type stimulator with no side-effects. From what my Dad saw, the block was mostly from nerve damage being created from the stimulation (I apologize, I don't remember all the specific details). Bottom line, I'd research any company you're considering getting a stimulator from.
Note: I'm more knowledgeable then the average person, but I'm no biomedical engineer. Definitely look into this stuff yourself and get other opinions. I do know it's definitely worth looking into.
Now, there is something that does seem to be a bigger breakthrough in this article, specifically the notation of having on-demand function without requiring some type of remote or etc. via a stimulator. This is new as far as I know, from the basics that I know this sounds more like helping a partial spinal cord injury rather then a full injury (My Dad works with full-spinal-cord injury patients only). I'm going to send this over to my Dad and see if he has anything to say on it.