During the gait cycle, the ankle joint will allow the foot to both dorsiflex, and plantarflex. Dorsiflexion means that the toes are pointed upwards, toward the shin, while the heel is resting on the ground. Plantarflexion is when the toes are pointed towards the ground, away from the shin, while the heel is lifted off the ground. Both of these motions are needed for an even normal walk.
However, toe walkers are unable to dorsiflex their foot. There are many causes for toe walking, but one common cause is called equinus. Equinus is a biomechanical abnormality in which the foot is pointed downwards in a plantarflexed position. There are two main groupings of equinus, which include:
- Osseous equinus: This type of equinus is caused because there may be a bony block around the ankle, which is preventing the foot from dorsiflexing, which results in a toe walk. This type of equinus is most commonly due to trauma and may only be noticed on one side.
- Soft tissue equinus: The Achilles tendon, which is formed by the ends of the calf muscles, attaches to the back of the heel. The calf muscles plantarflex the foot during gait. So, if the Achilles tendon is too tight or short, the foot will remain plantarflexed, which causes toe walking.
There are many causes for equinus. Some are:
- Trauma to the ankle: Trauma such as an ankle fracture may result in equinus. After a bone breaks, it will be repaired by the body; however, if the fracture does not heal the properly, the foot may not be able to dorsiflex.
- Wearing high heel shoes: High heels cause the foot to be held in a plantarflexed position. If a person were to wear high heels on a daily basis, the calf muscles will tighten, causing a tightened or shortened Achilles tendon, and will have a tendency to want to keep the foot in plantarflexion.
- Neuromuscular diseases: In some neuromuscular diseases, the calf muscles may overpower the other muscles in the legs that function to dorsiflex the foot. If this is the case, the foot will remain in a plantarflexed position. This is commonly seen in muscular dystrophy.
- Congenital: This means that the patient is born with a plantarflexed foot. This may be due to mal-positioning in the womb.
Equinus may cause more problems than just a toe walking gait. Other symptoms or problems that equinus may cause are:
- Achilles tendonitis: This is inflammation and irritation of the Achilles tendon that is caused because of the pulling and tightness of the calf muscles.
- Metatarsalgia: This is pain on the ball of the foot that is due to the constant pressure from toe walking.
- Arthritis of the midfoot or ankle: This will usually be located in the middle of the foot or ankle, which are constantly exposed to repetitive stress and pressure from toe walking
- Bunions or hammer digit syndrome: These toe deformities will result due to muscle imbalances associated with equinus.
Equinus is a treatable biomechanical abnormality. Some non-surgical treatment modalities include:
- Ankle braces and/or orthoses: Helps the ankle to be able to dorsiflex during gait, as well as orthoses helping the foot to function properly.
- Calf stretches: Works to relieve the tension and attempts to stretch the Achilles tendon.
- Night splints: Will keep the foot in a neutral or dorsiflexed position for the entire night, which will keep a constant stretch on the calf muscles in order stretch/lengthen the calf muscles and Achilles tendon.
If equinus has been a chronic problem and/or is too severe, these conservative treatments may be ineffective. If this is the case, surgical treatment will be needed.