Official Diagnosis: Tibia Stress Fracture

I promised I would deliver the results of the MRI. Not exactly what I wanted to share but the MRI did show a tibia stress fracture. The tibia is the larger of the two shin bones and as a weight bearing bone is more susceptible to stress fractures, particularly in the lower third.

 

Symptoms of a Stress Fracture Include:

• Pain (usually on the lower third of the tibia) that occurs after running long distances.
• Tenderness and swelling over the site of the fracture.
• Pain when you press into the shin. An X ray of the injured leg will often not show any sign of a fracture. Another X ray must be taken 4 weeks after the first and often the new bone can be seen where it has started to heal.

We did an X ray back in April and it showed no fracture. My doc and I had decided to just wait it out 8 weeks or so. Over that time I have improved so that I can walk normally, but still could not run. That is when I decided to push for a MRI.  

 

The two bones of the lower leg are called the tibia and fibula. The tibia is the larger of the two and its role is load bearing. The fibula is the smaller of the two and its role is mainly for muscle attachment. Either of these bones can have stress fractures. The most common site however is two to three inches above the bony bit on the inside of the ankle (medial malleolus) on the tibia bone.

 

Causes include:  

• Overloading the bone by continuous muscle contractions for example in running. 
• Stress distribution in the bone altered because of continuing to run when the muscles are particularly fatigued. (Muscles are unable to take some of the stress so rely more on the bone).  
• A sudden change in running surface for example going from grass training to lots of track or road running.  
• Lots of small impacts on the bone even though they may be very small, a cumulative effect can build up.

As with the hip stress fracture, I'm sure this is just another over-use injury. But that is the head-scratcher, as I wasn't really running like an idiot. Here are my run miles from late fall up to the time of injury:

 

October 2011 - 170 miles

November 2011 - 200 miles

December 2011 - 11 miles

January 2012 - 36 miles

February 2012 - 91 miles

March 2012 (first half only) - 42 miles

 

I had put in some heavy mileage towards the end of last year, but I was also coming off some of my most successful running in recent memory.

 

Sep 17 - Bismarck Half-Marathon 4th overall (419 total); 1st overall in Male Masters (40 & over); 1st in 50-54 AG (17 total). Time 1:25.04 

Sep 24 - Plymouth Fire Fighters 5K - 3rd overall (359 total) 18:41, course PR

Oct 2 - Du the Bear Duathlon, Houston, TX - 9th overall (259 total); 1st 50-54 AG (13 total)

Oct 8 - Fargo Mini Marathon 5K - 4th overall (695 total) 18:03, 1st 50-54 (16 total)

Oct 22 - Lincoln Family Downtown 5K; Phoenix, AZ 11th overall (296 total); 1st 50-59 (16 total)

Oct 29 - 37th Annual Red River Run; Moorhead, MN - 1st overall (84 total); 1st in 50-59 (15 total). Time 59:03

I then took time off in December to recharge the batteries. I slowly started up again in January and then brought the run mileage back to where I wanted it to be in February. That may have been too big a jump too early, though. By mid-March, the injury had occurred and I am sure I did myself in even further by jumping into the 10K when we visited London the first week of April.

So, how long will I be out? It is anyone's guess. I read anywhere from 4 weeks to 6 months. Since it has been 11-weeks since the London 10K my initial guess is up to another three months. So, perhaps in September. And begin to gear up for 2013.