Pronation refers to the inward roll of the foot during normal motion and occurs as the outer edge of the heel strikes the ground and the foot rolls inward and flattens out. A moderate amount of pronation is required for the foot to function properly, however damage and injury can occur during excessive pronation. When excessive pronation does occur the foot arch flattens out and stretches the muscles, tendons and ligaments underneath the foot.
There are many biomechanical issues that can contribute to excessive pronation, including weak foot intrinsic muscles, limited ankle dorsiflexion mobility and calf flexibility, weak ankle invertor muscles (e.g. posterior tibialis), weak forefoot evertor muscles (peroneus longus), poor hip strength and control, Anterior pelvic tilting, heel InversionIn a person who overpronates, the heel bone goes into an everted position meaning that it turns out away from the midline of the body. The opposite motion of eversion is inversion. Inversion is a motion that needs to be controlled to prevent the foot from excessively pronating.
Over-Pronation may cause pain in the heel of the foot, the foot arch, under the ball of the foot, in the ankle, knee, hip or back. The symptoms may be localized to one particular area of the foot or may be experienced in any number of combinations. Standing for long periods of time, walking and running may become difficult due to the additional stress and/or discomfort accompanied with these activities. Upon Visual Inspection, when standing the heels of the foot lean inward and one or both of the knee caps may turn inward.
Bunions, calluses and crooked toes may indicate alignment problems. So, it is important to ascertain the condition of a client's toes. Check the big toe to determine if the first joint of the toe is swollen, has a callus or bunion, and/or looks as though it abducts (i.e., hallux valgus) rather than pointing straight ahead. Also, look to see if the lesser toes seem to "curl up" (i.e., the person has hammer or claw toes). This may be indicative of damage to, or inflexibility of the plantar fascia caused by excessive flattening of the foot.
Non Surgical Treatment
One of the best forms of treatment for over pronation is wearing supportive shoes. Shoes should have ample support and cushioning, particularly through the heel and arch of the foot. Without proper shoes, there may be additional strain on the tissue in the foot, greatly contributing to or causing an occurrence of over pronation. Rarely is surgery considered to relieve the pain and damage that may have resulted from this condition. Orthotic shoe inserts are often the easiest and most effective way to correct pronation.
The MBA implant is small titanium device that is inserted surgically into a small opening between the bones in the hind-mid foot: the talus (ankle bone) and the calcaneus (heel bone). The implant was developed to help restore the arch by acting as a mechanical block that prevents the foot from rolling-in (pronation). In the medical literature, the success rate for relief of pain is about 65-70%. Unfortunately, about 40% of people require surgical removal of the implant due to pain.