Someone I saw four years ago walked back into the office. Same low back. Only now it's worse, it's running down the right leg, and that leg feels weak. "Doc, I figured it was the same old thing. I've been stretching, I've been icing, I've been waiting it out. But now the leg's giving out on me."
Okay. That's a different conversation than the one we had four years ago.
So here's what I told them, and here's what I'd tell you. Pain is one thing. Pain down the leg tells me a nerve is irritated. But weakness? Weakness tells me the nerve is affected enough that the muscle isn't getting the full signal. That's not normal. That's not good. And that's a reason to look again. Waiting it out, or repeating whatever we did last time, doesn't answer the question.
Let's go through the process.
Your spine is like your circuit breaker in the back of your house. Every nerve that comes out between two vertebrae is a switch that runs a room. One switch runs the kitchen. One runs the garage. In your low back, the switches at L4, L5, and S1 run the leg. That's where sciatica most often comes from. So if the lights are flickering in the leg, I don't go stand in the leg. I go to the panel. The leg is where it hurts. The low back is where the problem lives.
Number one is history and strength testing. I sit down and I ask. How long has the low back pain been there? Is it traveling down the leg? Which leg, and how far? When did the weakness start? Then I test it. I'll have you push against my hand with your foot, lift your toes, and walk on your heels. I check sensation with the pinwheel, because each nerve has its own map down the leg. I check reflexes. "Doc, why does that side feel duller?" That's the nerve telling us which switch it is.
Number two is the nerve scan. We do a surface EMG. It's like an EKG, but for your nervous system. It reads how each nerve root is functioning, level by level, up and down the spine. Your pain is the report you give me. The scan is the measurement. A lot of times the numbers line up with exactly what you've been feeling. And sometimes they show a level you'd kind of ignored.
Number three is the X-rays. This is the part I want you to hear. We take new digital films and look at disc height, alignment, and degeneration. Then I put them right next to the films from four years ago.
So that's what I did with this patient. Old films on the left. New films on the right. Whoa! Oh my god, do you see this? The disc spaces in the lower spine had closed down more. There was more degeneration in that same area. And I told them plainly, that's where your leg pain is coming from.
Why does that matter? Think about the disc as the spacer between two bones. With age and with load, discs lose height and they lose water. When the spacer gets thinner, the opening where the nerve exits gets smaller. Now go back to the circuit breaker. The switch is still there. But the wire coming out of the panel is getting pinched by the door. You might feel it as pain down the back of the leg. You might feel it as the foot dragging when you're tired. You might feel both.
Now, I want to be careful here. X-rays don't explain symptoms all by themselves. Plenty of people have narrowed discs and no leg pain at all. A narrowed disc doesn't always mean weakness. That's why I read the films together with the history, the strength testing, and the scan. When all three point at the same level, we're not guessing anymore. Now we can see it.
Without the old films, I'd be looking at a snapshot. I'd see narrowing, sure. But could I tell you if it changed? No. With the old films, I've got a before and an after. Four years. Same spine. Less space you can actually see. That's the difference between "probably" and "here it is."
So when do I think about spinal decompression? Here's my screening, and I'll keep it simple. How long has the low back pain been there? Is it traveling down the leg? Is there decreased disc space? And is there decreased disc space with degeneration? That last one makes someone a big candidate for decompression. For this patient, the film comparison plus the history plus the exam is what made decompression a reasonable option to put on the table and talk through.
But I don't recommend it unless the findings support it. Not everybody with back pain is a decompression patient. You come back for your Report of Findings, I walk you through your films and your scan, and I tell you either way. If it's not a fit, you'll hear that from me too.
So here's where you are. Your back pain has moved down your leg. The leg feels weak. Your last X-rays are years old. You can keep waiting and hoping it's the same old thing. Or you can find out whether something's changed.
If you've got old films, bring them. Dig them out of the drawer or call the old office, whatever it takes. We'll set them next to new ones and both look at the same picture. Then you get to decide what to do with what you see.