Calf Strain

The calf complex, which comprises of the lateral and medial head of the gastrocnemius and the deeper soleus muscle, are vital in being able to produce locomotion. Therefore, calf injuries are common, particularly in the athletic population involving high-speed running, acceleration and deceleration.

Both the gastrocnemius and soleus are responsible for plantaflexion the foot (pointing toes downwards) which is important for the propelling force during walking. When the knee is flexed, soleus is the main plantarflexor (such as during running).

During physical activity these muscles have to content with rapidly changing forces and length in the muscle increasing the risk of a calf strain. However, it can also occur in slow lengthening (eccentric) muscle contractions such as baller dancers or stepping backwards (off some steps, for example).

Depending on what muscle has been affected, people will report slightly different symptoms and therefore a thorough assessment is key. As the gastrocnemius crosses both the knee and ankle joint, it is at risk when the knee is fully stretched and the foot is placed into dorsiflexion and the muscle attempts to contract in a lengthened state.

Typically calf strains occur on the medial head (inner muscle) where a sudden, sharp pain is felt and in some cases people report a sensation that they have been kicked in the back of the leg. Soleus strains are less common, with people reporting a deeper, nagging type ache. Muscle strains are typically graded from 1-3:

• Grade 1 (mild): Only a few muscle fibres are affected. There is minimal pain and walking is not affected. There may be some mild stiffness first thing in the morning however strength is largely unaffected and full range of movement is still evident.

• Grade 2 (medium): A moderate number of muscle fibres have been affected with reports of acute, sudden pain, swelling and mild loss of function. There may be a mild limp with pain on palpation around the affected area as well as pain with resisted knee flexion

• Grader 3 (severe): A significant proportion of muscle fibres affected with the possibility of feeling a defect within the muscle belly. There may be severe acute pain where the person cannot continue their activity with a significant limp, swelling and eventually bruising. Active range of movement and strength will be affected.

A thorough assessment is crucial. In some instances, calf pain could be produced by altered neural dynamics (AND) where there is tension within the neural system that supplies the calf complex. Once this has been excluded, further assessment would identify:

• Altered walking pattern, with either pain when weight bearing through the affected side of discomfort during terminal stance where there is a stretch in the muscle

• Reduced ankle range of movement

• Tenderness at point of injury

• Swell

• Bruising may or may not appear

• Pain or discomfort when the muscle is being stretched

• Pain on contraction of the affected muscle

Once a diagnosis has been obtained, there are a number of interventions that can be used to help recover from a calf strain:

• Advice and Education

• Symptoms management particularly within the acute phase

• Activity modification

• Massage and mobilisation

• Home exercise programme – progressive loading

• Gait re education

• Electrotherapy

• K Tape

• Graded return to sport.