We continue our series on common foot and ankle injuries in sport. We will focus particularly on AFL, as this is one of the few sports still in play at the moment. Bone stress injuries are seen within the foot and lower leg each year amongst AFL players. These types of injuries can sideline players for long periods.

It is of interest to note that we are seeing an increase in these types of injuries in the clinic. Spikes in walking and running during Covid restrictions is most likely contributing. Thought this would be a great time to highlight the ‘What, Where and Why’ of bone stress related injuries.

What is bone stress…?                                                       

Our bones are constantly re-modelling and adjusting to changes in our activity. When our activity increases our bones adapt in an effort to become stronger. If we increase our activity too suddenly or don’t allow enough recovery time between training sessions this can exceed what our bones are able to tolerate. This sequence can lead to fatigue in our muscles and ultimately in the structure of our bones. They therefore become vulnerable and less able to tolerate the loads of the activity; leading to a bone stress injury.

A bone stress injury if caught early can be mild and present as a more local tenderness on a bone. However, if this load continues the local tenderness can increase to a stress fracture, whereby the bone develops a crack or break.

Bone stress injuries are common amongst walkers and runners too! With Covid-19 presenting significant challenges and changes to our lifestyles, it’s been great to see more and more people using their extra time to be more active. Given we have more time for exercise it’s important to be cautious as sudden increases in training volume can put us at risk of developing a bone stress reaction. In the clinic we’ve noticed an increase in metatarsal bone stress reactions. Many people have been increasing their level of running and walking, however not allowing long enough recovery time between sessions.

Where are they likely to develop…?                                                       

Bone stress reactions occur in bones which are under repeat loading. This is why the foot and lower leg are the most common areas we hear about.

In walkers and runners, the most common site we find bone stress reactions are in the long bones of the foot, called the metatarsals. They generally develop over a period of a few weeks and patients report a gradual increase in pain during exercise. There is often swelling over the top the foot and aching in the area after activity. If a stress reaction develops to a stress fracture, there will be an increased throbbing pain even with basic day to day activities as well as pain during rest and/or at night.

If detected and managed early, a mild stress fracture is likely to resolve within a number of weeks. However, there are more complicated areas of the foot and lower leg which are at risk of bone stress reactions.

With higher loading such as jumping and running movements involved in AFL there can be more sinister bone stress injuries. These can require longer recovery periods. The more complicated areas we find stress reactions are the calcaneus (heel bone), shin bone and navicular bone.

The navicular is a rather complicated bone due to its position in the foot and having restricted blood flow. It has a number of important muscles attaching to it and is often under large compression forces. Combined the loads, compression forces and poor blood flow and you often have a complicated and prolonged healing process. This injury has often ended an AFL players season due to its challenges to heal.

AFL players to have suffered from navicular stress fractures include Jesse Hogan, Jack Trengrove and James Hird. This season Essendon player Tom Hird has developed a navicular stress fracture and Adelaide player Wayne Milera has sustained a 5th metatarsal stress fracture. Former Geelong and Great Western Sydney player Stevie Johnson also suffered from stress fractures during his career.

Common areas for stress fractures injuries in the foot and ankle:

Why do Bone stress injuries develop…?                                                 

Bone stress injuries development is strongly linked to an individuals training loads. However, there are a number of contributing factors that can lead to someone developing a bone stress injury:

  • A sudden increase in activity
  • Increase in more dynamic training (jumping, skipping, plyometrics)
  • Changes in footwear – lower pitch, softer, more flexible
  • Tight calf muscles
  • Muscle strength and endurance
  • Foot mechanics – biomechanical factors
  • Running technique
  • Reduced recovery time between sessions
  • Reduced sleep
  • Changes in diet or nutrition
  • Hormones
  • Age
  • Low bone density
  • Previous injury history – past bone injury

Management of Bone stress…                                                      

Treatment of early stage bone stress reactions can include:

  • reducing your walking or running distances
  • including extra rest days
  • wearing supportive shoes
  • ensure adequate sleep

This will allow the bone to re-model and recover from being overloaded. Depending on the severity of the bone stress injury recovery ranges from 2-6 weeks if treated early.

In the context of the AFL, treatment is likely to include a reduction in training loads and running, with possible short periods in an immobilization boot. Players will maintain their fitness with other forms of exercise, including cycling and swimming to allow the bone injury to heal.
Treatment will also include using supportive running shoe rather than footy boots and possibly orthotics.

More complicated Stress fractures, such as the navicular will require a longer period of more aggressive offloading. This could be in a CAM walker for 6-12 weeks. This is why you may have noticed AFL players with navicular stress fractures spending lengthy periods on the sidelines. If not responding to conservative management a navicular stress can sometimes require surgical fixation to facilitate the healing process.

As we mentioned there have been a lot of bones stress and stress fractures identified in the clinic during the lockdowns. If detected and treated early we can help you to return to activity quickly and safely.

Fluid Movement Podiatry are able to accurately diagnose and treat all conditions of the foot and ankle. If you’re in pain and are not able to be as active as you like, please book in for an assessment so we can help you return to your best.

Stay safe and active,

Stuart and Ben
Fluid Movement Podiatry