Repetitive Strain Injuries – Shin Splints
Overusing certain muscles and tendons without proper recovery can lead to repetitive strain injuries. An extremely common one is known as ‘shin splints’ which is the generic term for exercise induced anterior leg pain. When the muscles around the shin are repeatedly contracting they cause myofascial strains and inflammation along outer layer of bone. A study found that 13-20% of runners will experience shin splints over a period of 2 years.
There are two main types of shin splints:
1. Anterior shin splints – The pain is on the anterior lateral side of your shin and is due to the muscles on the front of your shin. These include tibialis anterior, extensor hallucis longus, and extensor digitorum longus.
2. Posterior shin splints – The pain is on the anterior medial side of your shin and is commonly referred to as medial tibial stress syndrome. It impacts the muscles on the back of your shin such as tibialis posterior, flexor hallucis longus, flexor digitorum longus, and soleus.
Causes of Shin Splints:
The leading mechanism of injury is repetitive eccentric contraction which can occur from running or jumping on hard surfaces. Training errors such asgoing for too long, too fast, and too much are an extremely common reason. Improper training or having poor technique will also increase the stress on your tissues. Foot hyper-pronation (flat footed) is a significant risk factor because repetitive foot collapse causes unequal stress on your muscles. Other structural differences such as leg length discrepancies, excessive hip rotation, and knee alignment are potential risks. Being a female, runner, military personnel, or dancer is also related to a higher incidence.
Rest and Ice: Giving yourself 1-2 weeks of rest and icing will decrease pain and inflammation so that you can slowly return to activity without re-injuring.
Activity modification: Once cleared for activity, start with a decrease in mileage and frequency of your training. Also ensure you start on a softer surface such as dirt instead of concrete.
Adjustments: Manipulating the foot, ankle, fibular head, hips, and lower back can be beneficial for restoring motion and improving biomechanics.
Myofascial release: Working on the overactive muscles such as the gastrocnemius, soleus, tibialis posterior, and tibialis anterior will help decrease muscle tension and pain.
Strengthening: To ensure you don’t get injured again, strengthening the muscles around your shin and the intrinsic muscles of your feet will create more stability in your movements. Focusing on single leg balance and proprioception is another key component in coming back stronger and more resilient.
Shin splints and tibial stress fractures can present very similarly. Research has shown that medial tibial stress syndrome may be an inflammatory precursor to tibial stress fractures especially in females. Healthy bone often responds to exercise stress by remodelling itself more densely.
But when the healthy remodelling response is unable to keep up with excessive training that is when bones weaken. If symptoms worsen or do not improve, talk with your medical provider about imaging.