Don’t Ignore Wrist Pain — What To Know About Scaphoid Fractures


⌚️ read time: 6 minutes


If you’ve been reading for a while, you may remember the previous ‘guide to ski and snowboard injuries’ I made, complete with a visual roadmap of wrist injuries (find it here).

And you may also remember that one of the ‘double black diamond bad injuries’ was a scaphoid fracture.

Well. Today let’s try to tackle this complicated and nuanced topic by boiling it down to its essence.

And why is this such a bad actor? The symptoms can be subtle (meh, feels just like a wrist sprain) starting an irreversible course to destructive wrist arthritis if not treated early.

This seems to be a theme of my articles these past few weeks (I Jammed My Finger…How Do I Know If It’s Broken?)…guess I’m saddened by seeing these after they’ve been missed.

 

Figure 1 - The eight carpal bones of the wrist

Photo: https://www.scientificanimations.com, CC BY-SA 4.0 via Wikimedia Commons

 

The scaphoid is one of eight carpal (wrist) bones and is the most common to break (see Figure 1).

As mentioned above, scaphoid fractures can seem initially insignificant and can even be missed on first evaluation. But. Mismanage a scaphoid fracture, and the patient is nearly guaranteed a lifetime of wrist dysfunction.

Wrist pain is not to be ignored

I would love nothing more than to ease your fears and tell you that you don’t need to see a doctor for every little wrist injury. And while that’s probably true in some respects, you do need to be more careful than you might think.

If you have had a significant injury to your wrist, whether from a fall or otherwise, I urge you to see a specialist and have an x-ray taken.

It all boils down to this: the consequences of an untreated scaphoid fracture can be dramatic. Plain and simple.

What begins as a treatable injury rapidly degrades into a problem that is very difficult to treat after just a few weeks.

Ask any hand surgeon and they will tell you many stories of the patient who comes in after a year or two of wrist pain.

  • “It wasn’t that bad.”

  • “It hurt for a bit but then it got better.”

  • “I just thought it was a sprain.”

I’ll get into more specifics as we go along. But suffice it to say that an untreated scaphoid = a scaphoid that won’t heal. And a scaphoid that won’t heal = a predictable path toward destructive wrist arthritis.

Please. If you hurt your wrist, just get an x-ray. I know it’s not always easy, but I promise you the juice is worth the squeeze.

For scaphoid fractures, diagnosis is everything

This next point will give you a little window into how doctors are trained to think. Intuitively, this should make sense.

I cannot start effectively treating you until I have a diagnosis.

Obvious right? But this can be easily overlooked.

I make this point relative to scaphoid fractures because of an unfortunate truth. As much as I’ve urged you to get an x-ray after a wrist injury…the first set of x-rays after a scaphoid fracture can often appear normal. The fracture is missed.

This is a well-known problem in the medical community that is specific to scaphoid fractures.

The scaphoid is a tiny bone that typically cracks, but doesn’t always displace. Its natural orientation is also tipped forward relative to the flat plane of the wrist. And every fracture plane is itself different.

So. Unless the x-ray beams happen to be directed exactly down the plane of your fracture, the broken bone can be initially invisible (see Figure 2).

 
 

This is why it’s crucial to seek treatment from someone with training in the hand and wrist. In addition to your first x-ray, a physical examination of your wrist yields important information about the likelihood of a scaphoid fracture.

When a patient comes to me with wrist pain, and they hurt when I push directly over the scaphoid (we call this ‘tenderness’), but they have ‘normal’ x-rays, I still put them in a cast. I ask them to return in 10-14 days for repeat x-rays. This is the ‘industry standard.’

As bones begin to heal, within a couple of weeks, they will show changes visible on x-ray. When the patient returns to me, I take them out of the cast, re-examine them for pain over the scaphoid, and repeat the x-rays.

This method yields one of three outcomes:

  1. No pain at the scaphoid, no evidence of fracture on x-ray

  2. Continued pain at the scaphoid, no evidence of fracture on x-ray

  3. Pain at the scaphoid, and a now obvious scaphoid fracture on x-ray

Outcomes 1 and 3 are pretty straightforward. If 1, the patient can slowly resume activities as their wrist feels better and better. We are 99.9% sure they don’t have a scaphoid fracture. If anything doesn’t seem right in the subsequent weeks, I urge them to return for repeat evaluation.

If 3, we have a diagnosis! Time to treat. We will discuss more below.

2 is the grey zone. We still don’t have a diagnosis. We need an MRI. An MRI will tell us without a doubt whether there is a tiny little fracture line in the scaphoid or not.

You may be asking…why not just get the MRI from the start?

The (unpalatable) answer is cost. MRIs are very expensive, both to you and to the healthcare system. Most patients would rather avoid this bill if given the option. Some insurances won’t even pay for the MRI after the first visit.

While nobody likes to talk about costs, this is an unfortunate reality of our healthcare system that cannot be ignored.

Scaphoid fracture treatment choices hinge on fracture displacement

Ok, we finally have a diagnosis! Let’s talk about treatment.

Not so fast.

The entire treatment discussion hinges on one question (not entirely true, but I’m giving you a concise version).

Is the scaphoid fracture displaced or not displaced?

Non-displaced means it truly has just cracked in place. The bone ends are still touching. This type of fracture behaves very differently than one with displacement.

A displaced fracture? We’re talking even 1mm of displacement changes everything. And this distinction can be difficult to make. 1mm is small!

If the answer isn’t obvious on x-ray, a CT scan may be needed to determine the displacement. Again, this may seem like overkill, but the entire treatment algorithm changes based on this characteristic.

Many hand surgeons argue that even being able to see a scaphoid fracture on an initial x-ray means the fracture is at least 1mm displaced. The argument here is that truly non-displaced fractures are rarely visible on initial x-ray.

Why does this matter so much? It all comes down to blood supply.

Most bones in our body have ample, and often multiple, blood supplies. But in the case of the scaphoid, the majority of the blood supply comes from one artery. And a fracture of the scaphoid risks disrupting this near-microscopic artery. Can you see where this is going?

A non-displaced fracture carries a very low risk of disrupting the artery. But a displaced fracture is a whole different beast. These come with a much higher risk of cutting off the blood supply to the scaphoid.

Again, this heavily informs our treatment. Bones need blood to heal. And if your scaphoid fracture can’t get blood? It won’t heal. We need to help it.

This is why we must get a diagnosis when you have a wrist injury and we must start treating it early enough to help the scaphoid heal.

Scaphoid fractures are treated with (a lot of) casting or surgery

As indicated above, our treatment discussion hinges primarily on one variable — displacement (in reality, there is more nuance we consider, but this covers the basics).

Non-displaced scaphoid fracture

If the fracture is non-displaced, you have two options. The first is a cast and the second is surgery. Non-displaced fractures heal about 90% of the time, regardless of which option you choose.

Read this point again carefully. With the evidence we have, the chances of healing remain the same with casting versus surgery. The only advantages that surgery provides are faster healing and less time in a cast.

To translate. The chances of healing are no better with surgery. But. IF your fracture is one that was going to heal anyways (90% of non-displaced fractures), our current evidence suggests surgery will help it heal faster. And surgery will offer you less time in a cast (not no time in a cast — you will still need a cast after surgery).

Because the blood supply to this bone is poor, it can take a long time to heal. In a cast, these can take anywhere from 3-5 months to heal. That means 3-5 months in a cast.

Obviously, that’s no joke. That is a long time to be in a cast, and this can have significant consequences in terms of wrist stiffness and weakness that will take many months to overcome following the completion of casting.

Alternatively, you may elect for surgery. In a non-displaced scaphoid fracture surgery, I will place a type of screw called a headless compression screw straight down the middle of the scaphoid. The screw will be housed entirely inside the bone. This provides compression and stability across the fracture while it heals (see Figure 3).

 
 

In most cases, this can be done through an incision as small as 1 centimeter!

Some surgeons will allow patients to start moving and using a brace as early as 2 weeks after this surgery. In my practice, I still use a cast for 6 weeks. The consequences of not healing the scaphoid fracture are just too great to risk, in my opinion. An extra 4 weeks of casting seems worth it to me.

Displaced scaphoid fracture

As you may have noticed from previous articles, I make a concerted effort to lay out all potential treatment options for my patients so you can choose which treatment best suits you and your goals.

Unfortunately, in the case of a displaced scaphoid fracture, you really only have one option. Surgery.

The healing potential of a displaced scaphoid fracture falls under 50%, even with as little displacement as 1mm. This really constrains our options to make you better and avoid serious longterm complications.

If we get to treating your scaphoid fracture early (within a couple of weeks), I can often manipulate the wrist so as to put the scaphoid fracture back in line and place the same screw as described above for non-displaced fractures.

If more time has passed, or if the scaphoid is significantly displaced, I sometimes need to make a larger incision to get the pieces back in alignment before placing the headless compression screw. The success of this surgery depends largely on restoring the appropriate architecture to the scaphoid so that it can begin the healing process.

It’s a big deal if the scaphoid doesn’t heal

I’ve alluded to it a few times thus far — what happens if your fracture doesn’t heal?

In reality, there are actually a couple of phenomena we worry about. One is lack of fracture healing (nonunion). The other is avascular necrosis (AVN), which is when part of the scaphoid bone dies as a result of no blood supply. While there are some important subtle differences, I’m going to lump them together for this brief discussion on the topic (entire textbooks have been written on this subject alone).

The scaphoid is an interesting bone that spans the two rows of carpal (wrist) bones, and thus plays a tremendously important mechanical role in stabilizing the wrist. You can think of it as the keystone of an arch (see Figures 4 and 5). Without it, the arch collapses.

 
 

If the scaphoid loses its inherent stability as a result of poor healing (nonunion or AVN), the entire ‘arch’ will collapse. The forces across the wrist will pull the wrist bones into a predictable form of degeneration, and eventually, arthritis.

This is known as scaphoid nonunion advanced collapse, or SNAC wrist.

Without the scaphoid’s stabilizing structure, each adjacent wrist bone gets pulled just a little bit off-axis. This causes the bones to rub together asymmetrically, which leads to increased wear and tear on the soft cartilage padding between bones. Once this imbalance begins, the bones get pulled more and more off-axis and the cartilage continues to wear away until it is gone, resulting in full-blown wrist arthritis.

While there are some treatments available for this form of wrist arthritis, they nearly all result in a significant loss of wrist range of motion and grip strength. They are all far more invasive and have far worse outcomes than the initial surgery used to fix a fresh scaphoid fracture.

This is why I urge you. Please get a wrist x-ray if you have sustained an injury resulting in significant wrist pain. Don’t assume it will be ok, as the time to intervene is right away.

 
 

Takeaways:

  • Pain over the back or thumb side of your wrist after an injury cannot be ignored

  • While many times it’s ‘just a sprain,’ scaphoid fractures can initially be less painful than expected and have a low chance of healing on their own

  • A scaphoid fracture that doesn’t heal will inevitably progress to a painful, limiting wrist arthritis that cannot be undone

As I mentioned above, entire textbooks have been written about this nuanced and difficult topic of scaphoid fractures. I hope this primer provides you with the most important information regarding scaphoid fractures, so you can make the appropriate educated decisions for your health.

 
 
 
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