Stress Fractures � Diagnosis And Recovery

The dreaded “stressy” is so feared that I find myself starting many diagnosis discussions with “well you’ll be pleased to know it is not a stress fracture”. The relief is palpable!

What happens when it is a stress fracture though?

The process of a stress fracture is a simple one. All of our bones are being constantly remodelled by cells that resorb the existing bone and cells that rebuild it. This rolls along throughout our lives, but is influenced greatly by mechanical stress – running being a big one. If there is an increase or alteration of mechanical stress in one particular area, then the bone remodelling process speeds up. If there is repeated stress, the remodelling process can get out of sync. The cells resorbing the bone work quicker than those rebuilding it, leading to an area of bone weakness. If the increased mechanical stress continues then the bone can crack or fracture microscopically. This is a bone stress injury and is when things become painful. If you ignore it then it can lead to a bigger crack and a full stress fracture.

The causes of stress fractures  

Put simply, something has altered to put more stress on the particular bone resulting in the behaviour described above. This can be one or a combination of:

• An increase in training
• Intensity – track work or hills
• Duration – longer sessions or runs
• Type – From grass to track or road
• Poor biomechanics
• Alteration in technique (more toe impact for example)
• Alteration in gait – limping because of another issue
• Shoes – new, old or worn  

Additional factors

The body requires good bone metabolism to be efficient in its remodelling process. Vitamin D and calcium levels are important and are often low at the end of the winter. Further, the levels required for athletes are higher than those for the general population.

Blood test levels for non-athletes put normal Vitamin D levels at 50nmol/l. Many sports medicine physicians say that this is too low and that supplementation should be undertaken until it is in excess of 100nmol/l. However, this is a discussion for another article and is best addressed by a Sports Medicine Doctor. Further the “female triad” of irregular periods, osteoporosis and disordered eating are huge factors and should not be ignored.  

The symptoms of stress fractures

Pain is the basic sign. It is a steady ache in the area initially after a run but then can be felt during it as the issue progresses – the pain then comes at rest and at night. There is a focal point of pain on the bone usually about a thumb’s width across with a diminishingly tender area either side. Occasionally there is a low-grade swelling and slight colouring of the skin. In the early stages the pain really only occurs when you have finished a run or after being on your feet for a while.

When it is established, the pain is more constant and particularly painful on loading. The difference is all related to how far along the aforementioned process you are. A skilled physiotherapist will rule out all the other possibilities of tendon and muscle issues as well as infection and additional problems. Sometimes ultrasound is used to test the area. (Therapeutic as opposed to scanning ultrasound) Essentially the ultrasound hurts a stress fracture.  

X-rays are poor at showing stress fractures unless the healing process is well on its way, which is around three weeks from the onset. MRI is the imaging of choice and this will show an area of bone oedema or fluid in the bone where it should not be and also any significant cracks or fractures. Imaging is not essential to diagnosis, but it helps in giving a time scale for recovery.

How to treat a stress fracture

Rest is the only option. Putting further weight through it will only make the problem worse and delay the healing. There are no shortcuts.

The more you fiddle around with seeing if you can get away with some cross-training, the longer it will take to heal. A full-blown stress fracture takes on average six weeks to heal. For the bigger bones such as the femur it can be eight to 12 weeks. If you can stop running (a tough discipline) when the first signs appear it can knock a couple of weeks off the healing process.

The pain from day-to-day and at rest normally settles within a week or so. A cast or boot and crutches until it is pain-free also helps. The difficult part of treating a stress fracture is not the early weeks because the pain tells you that it is not possible to train. The difficult part is when the pain has settled. The temptation to “do a bit” is tangible. However, please don’t! You will simply stress it and slow the healing process.  

Once you have rested it for six weeks and you have had no pain for at least three weeks and are walking comfortably then it is time to start the next phase of the rehab – and it needs to be viewed as rehab.

This is a gradual return to running in a way to increasingly load the bone. Bone responds to load by getting stronger, but you have to do it slowly to allow for the adaptation. The usual routine is to jog for two-minute increments each day, two days on, then one day off. Start with a two-minute jog only, then four minutes the following day and then have a day off. Progress like this over a three-week period and this will take you up to 30 minutes.    

The bigger picture

As discussed earlier, you need to look at any biomechanical reasons why you overloaded that one part of the bone and deal with those or you will be back with another stressy ! Further you will have weakened and tightened in areas while not running and a full assessment of the legs will give you a nice list of work to do. This is a good reason to try our Biomechanical Assessment series to start to identify imbalances. Alternatively, a visit to a suitably experienced physio and possibly with the intervention of a podiatrist would be a good idea.  

Have a good look at your training diary and an honest assessment of the progression of load you subjected yourself to. If there are some clear errors, then take it on the chin and learn from it. If not, then have someone else look for an unbiased view.  

If there is still nothing apparent, then you have to be suspicious of your biomechanics or general bone health. I would therefore encourage you to see your GP or preferably a sports medicine physician if you have suspicions about your bone metabolism. This would be a possible lack of sun exposure and vitamin D in recent months, irregular periods or erratic eating. This can lead to poor bone health and stress injuries.

There is little point to all the rest and careful rehab if you are not healthy enough to heal properly. A stress injury is often a good time to be totally honest with yourself.