Anatomy of Running Injuries

Running is one of the most popular sports in the country with roughly 6.8 million people participating in some form of running on a regular basis last year. There are many health benefits of running on a regular basis that include, improving cardiovascular fitness, which in turn lowers the risk of conditions such as type 2 diabetes, heart disease, strokes and high blood pressure.Running can also increase bone density, strengthen muscles and tension, improve joint stability, improve mental health and aid in weight loss. While there are so many benefits to running all too often we are seeing people breaking down through overuse injuries - doing too much, too soon. This is especially true of beginners or people who are returning to running after a period of inactivity.

Up to 70% of recreational or competitive runners sustain overuse injuries in any 12 month period. Overuse injuries can occur from training errors (running frequency, duration, distance, speed and lack of leg strength and flexibility) and inappropriate surfaces, terrain and footwear. Overuse injuries, as a result of training errors, are more common than acute injuries such as ligament and muscle sprains and strains. 42% of all running injuries are to the knee, followed by 17% to the foot/ankle, 13% to the lower leg and 11% to the hip/pelvis. Specifically the most common running injuries are Patellofemoral Pain Syndrome (runners knee), followed by Achilles Tendinopathy, Iliotibial Band Syndrome and Plantar Fasciitis. Below we will go into more depth of the specific causes of each injury and the things you can do to help prevent them from happening.

Patellofemoral Pain Syndrome (Runners knee)

Patellofemoral Pain Syndrome (PFPS) is used to describe pain around the anterior knee cap. PFPS is an umbrella term used to embrace all pre patellar and retropatellar pain in the absence of any other diagnosis. Numerous structures around the patellofemoral Joint (PFJ) are susceptible to overload and therefore a potential cause of pain. These structures include lesions to the articulating cartilage of the patellar and femur, inflammation of the synovium, soft tissues such as the lateral retinaculum and finally the infrapatellar fat pad. PFPS can be caused by a single maximal overload or lower magnitude repetitive overload.

Factors that contribute to Patellofemoral Pain Syndrome

Patellofemoral pain is likely to be initiated by increased or unaccustomed loads, such as, increasing training distances too quickly or running too far after a long layoff from running. These factors can be split into two categories: extrinsic and intrinsic. During running extrinsic factors are created by the foot hitting the ground is moderated by body mass, speed of gait, surfaces and type of footwear. The number of loading cycles and loading frequency of loading also play a part.

Intrinsic factors can influence how the joint is being loaded. Distribution of the load is influenced by the alignment of the patellar in the femoral trochlea also known as patella tracking. Factors that affect this include rotation of the femur or tibia which is determined by hip strength, trunk kinematics, subtalar pronation and muscle flexibility. More locally to the joint factors include the bony shape of the patella and trochlea, soft tissue tension and neuromuscular control of the quadricep muscles.

To key to recovering from PFPS is to assess each one of these factors and identify any deficiencies whether they be intrinsic or extrinsic, and addressing each issue in turn.

Achilles Tendinopathy

Achilles tendinopathy is a condition that causes pain, swelling and stiffness of the Achilles tendon. It is thought to be caused by repeated tiny injuries (known as microtrauma) to the Achilles tendon. After each injury, the tendon does not heal completely, as should normally happen. This means that over time, damage to the Achilles tendon builds up and Achilles tendinopathy can develop.

There are a number of things that may lead to these repeated tiny injuries to the Achilles tendon. For example:

Overuse of the Achilles tendon. This can be a problem for people who run regularly. (Achilles tendinopathy can also be a problem for dancers and for people who play a lot of tennis or other sports that involve jumping.)
Training or exercising wearing inappropriate footwear.
Having poor training or exercising techniques - for example, a poor running technique.
Making a change to your training programme - for example, rapidly increasing the intensity of your training and how often you train.
Training or exercising on hard or sloped surfaces.

Achilles tendinopathy is also more common in people who have certain types of arthritis, such as ankylosing spondylitis or psoriatic arthritis. It is also thought that your genetic 'makeup' (the material inherited from your parents which controls various aspects of your body) may play a part for some people who develop Achilles tendinopathy. It is also more common in people who have high blood pressure, high cholesterol or diabetes. People who are taking medicines from a group called fluoroquinolones (for example, the antibiotics ciprofloxacin and ofloxacin) also have an increased risk of developing Achilles tendinopathy. Achilles tendinopathy used to be known as Achilles tendonitis. In general, 'itis' usually refers to inflammation, so tendonitis would mean inflammation of a tendon. However, Achilles tendinopathy is now thought to be a better term to use because it is thought that there is little or no inflammation that causes the problem.

Iliotibial Band Syndrome

Iliotibial band syndrome (ITBS) is a common knee injury that usually presents with pain and/or tenderness on palpation of the lateral aspect of the knee, superior to the joint line and inferior to the lateral femoral epicondyle. It is considered a non-traumatic overuse injury, often seen in runners, and is often concomitant with underlying weakness of hip abductor muscles. The current theory is that this condition is likely to be caused by compression of the innervated local adipose tissue. Studies have described an ‘impingement zone’ occurring at, or slightly below, 30° of knee flexion during foot strike and the early stance phase of running. During this impingement period in the running cycle, eccentric contraction of the tensor fascia latae muscle and of the gluteus maximus causes the leg to decelerate, generating tension (compression) in the iliotibial band.

ITBS is one of the most common injuries in runners presenting with lateral knee pain, with an incidence estimated to between 5% and 14%. Further studies indicate that ITBS is responsible for approximately 22% of all lower extremity injuries.

The causes of ITBS is often multifactorial. Long distance running is a common cause of ITBS, especially if running on slightly banked ground, as the subtle drop of the outside of the foot stretches the ITB, increasing the risk of injury, Sudden increases in activity levels can also lead to ITBS. Although repeated tissue compression leading to irritation is best supported by recent evidence, there are a number of other trains of thought regarding the evolution of this condition.

When the knee is positioned in extension the iliotibial band lies anterior to the lateral femoral epicondyle. When the knee is positioned in 30° of flexion the band moves posteriorly to the lateral femoral epicondyle. It is hypothesised that friction can therefore occur between the posterior edge of the iliotibial band and the underlying lateral femoral epicondyle.

Muscle weakness of the hip abductors is also associated with iliotibial band syndrome as this causes increased hip internal rotation and knee adduction. This was found as a significant issue for athletes with iliotibial band syndrome. Another proposed etiology is chronic inflammation of the ITB bursa.

Plantar Fasciopathy

Plantar fasciitis is the result of collagen degeneration of the plantar fascia at the origin, the calcaneal tuberosity of the heel as well as the surrounding perifascial structures.

The plantar fascia plays an important role in the normal biomechanics of the foot.
The fascia itself is important in providing support for the arch and providing shock absorption.
Despite the diagnosis containing the segment "itis," this condition is notably characterized by an absence of inflammatory cells.

There are many different sources of pain in the plantar heel besides the plantar fascia and therefore the term "Plantar Heel Pain" serves best to include a broader perspective when discussing this and related pathology.

This is often an overuse injury that is primarily due to a repetitive strain causing micro-tears of the plantar fascia but can occur as a result of trauma or other multifactorial causes.

There are many risk factors which contribute to plantar heel pain including but not limited too:

Loss of ankle dorsiflexion (talocrural joint, deep or superficial posterior compartment)
Pes cavus OR pes planus deformities
Excessive foot pronation dynamically
Impact/weight-bearing activities such as prolonged standing, running, etc
Improper shoe fit
Elevated BMI > kg/m2
Diabetes Mellitus (and/or other metabolic condition)
Leg length discrepancy
Tightness and/or weakness of Gastrocnemius, Soleus, Tendoachilles tendon and intrinsic muscle.

The key to addressing any of these common running injuries is to speak to a trained professional who has experience of dealing with these issues. They can identify the factors that are causing your pain and put in place evidence based treatment plans to get you back to running in the shortest possible time.