It’s official, I have a stress fracture. Actually, I’m slightly late writing this, so I suppose now I have a recovering stress fracture. Either way, it’s not ideal! With a lot of extra time on my hands over the last few weeks, I’ve been busy reading almost every article I could find on the topic. I thought I’d do a brief round up of the frustrating world of the stress fracture in the hope that there are some learning points.
What is a stress fracture?
You have 206 bones in your body, all made up from three main cell types. Osteoclasts (bone destroyers), osteoblasts (bone builders) and osteocytes (bone maintainers). They go through a constant cycle of regeneration, so the chances are, if you’re older than 20, you now have an entirely new set of bones from the ones you were born with. Mind blowing!
Just like muscles, bones get stronger with exercise. In response to loading, such as weight training or running, certain bone cells produce proteins, particularly collagen. In optimal conditions, these proteins will mineralise improving the bones density and making it stronger.
If you continue to overload a bone in a repetitive way however, and don’t give it time for this remodelling process to take place, then the structure of the bone will gradually weaken and a crack can appear at the point of greatest stress. Wham, bam, you have yourself a stress fracture.
Stress fractures most commonly occur in weight bearing bones such as the tibia (shin bone), navicular (the inner arch of the foot), 2nd and 3rd metatarsals (forefoot) and less frequently in the hip, femur (thigh bone), pelvis and 5th metatarsal. Mine was a stress fracture of my 5th metatarsal, or baby toe bone to be technical!
Who is at risk of developing a stress fracture?
Me, apparently! Or more specifically…
People with two X chromosomes!
Being female is unfortunately one of the biggest risks. Research has shown that there are several possible reasons for this, including things like women often having less muscle bulk for shock absorption and a lower aerobic capacity.
The other risk of being female is that if either your body fat percentage drops below a certain threshold (this will differ between individuals), and/or you exercise excessively (again, there is no set amount for what classes as excessively) then you run the risk of developing something called amenorrhea. The main noticeable symptom of this is that your periods stop. This might seem like a convenient fix to a monthly problem, but the repercussions are far more serious. It is thought that the reduction in the hormone oestrogen that is associated with not having periods, affects the process of bone regeneration. Although it’s not fully understood, it seems to result in a disproportionate amount of resorption compared to formation, reducing the bones density and making it far more vulnerable to stress fracture.
Increasing your mileage too quickly, or without preparing your body with enough strength and conditioning work first is a huge risk factor. As we’ve already talked about, bones will get stronger with loading, but this process takes time. Adaptations to bone density primarily take place during rest periods, which is why these should be a vital part of any training plan. Falling into the trap of overtraining by trying to catch up on missed runs, or continually running ‘easy’ miles too hard doesn’t allow your body time to recover and ultimately increases your risk of a stress fracture.
Medical conditions or a history of previous stress fractures
Conditions that directly affect your bone density, such as osteoporosis or osteopenia, or the long term use of steroids all increase the risk of a stress fracture. Although stress fractures are not quite like buses, having one stress fracture does make you statistically more likely to have another. A simple blood test can be recommended to ensure you are not deficient in vitamins such as vitamin D that play an important part in bone health that could cause these recurrent problems.
What are the symptoms of a stress fracture?
For me, the main symptom was the same as it is for the majority of people. Pain. Pain that gets worse with use and eases again with rest. Mine was unusual in that the pain didn’t build up gradually over a period of weeks. It was a reasonably sudden onset over only a couple of runs. When I really think back, I did have a niggle for a week or so about a fortnight before the main problem, but nothing major. The pain is usually pinpoint-able. I could put one finger on where it hurt. Stress fractures don’t usually result in a generalised vague sort of pain that some other injuries do.
Most searches will list swelling as a symptom. I didn’t have any, and the few I picked up in physio clinic have very rarely showed any signs of swelling either.
It’s easy to assume that all fractures show up on X-ray, but often stress fractures don’t, particularly in the early stages. When the fracture starts to heal there will be some callus formation (bony repair) and this can often be seen on X-ray, but until that point, an MRI is the only way to fully exclude a stress fracture. It’s quite possible to have a ‘normal’ X-ray, but still have an undiagnosed stress fracture.
How do you treat a stress fracture?
The truth is that this will vary depending on where the fracture is. For simple fractures with good healing potential, just reducing the impact of training might be enough. I had a walking boot for a month because 5th metatarsals are slightly more complex in the fact that the blood supply isn’t as good and therefore the healing potential of the bone is slightly compromised.
Stress fractures of bones such as the navicular in the foot, sometimes require a full cast and even complete non-weight bearing in order to allow the healing process to occur. It’s very rare that stress fracture need surgical intervention, but occasionally if the healing process fails, orthopaedic action such as pin and plating may be required.
How do I reduce my risk of getting a stress fracture?
I’m possibly not the right person to ask about this, am I? But as a rule:
- Follow the 10% rule and don’t increase your mileage by more than 10% each week
- Make sure you don’t run your easy miles too hard
- Allow a drop back week every 3 or 4 so that your body has time to adapt and recover
- Include enough strength and conditioning work in your training programme
- Change your trainers regularly
- Make sure you adequately fuel your training
- If you live somewhere that doesn’t see a lot of sunshine (like the UK in winter!) consider taking a vitamin D supplement
- Ensure you get sufficient rest and sleep
- Be male??
- Heed the warning signs. Amenorrhea is NOT a normal side effect of training. Get niggles checked out by a specialist as soon as they present
- Don’t wait until your body protests before you give it a rest day
In truth, I actually think I’m quite unlucky. On the whole I follow these rules to a T. I think in hindsight, I probably should have taken a bit more time to recover after Bournemouth half marathon before starting a new training block. I also had a spell when I competed in gymnastics where I suffered from amenorrhea and even though that was more than ten years ago now, maybe there are some longer lasting effects.
Either way, you can’t change the past, but you can learn from it. You can also learn from others. So train hard, train fast, but make sure you always train healthy.