The hallux varus is a deformity of the foot little frequent. It consists of the deviation of the first toe towards the middle axis of the body, that is to say towards the interior. It is the opposite deformity to hallux valgus ( bunions ) where the toe deviates externally approaching the second toe. Hallux varus is a deformity involving three movements of the first toe: supination of the first metatarsophalangeal joint, hyperextension of the first metatarsophalangeal joint, and hyperflexion of the interphalangeal joint of the first toe.
This technical explanation of the deformity is explained in a simple way, understanding that the big toe deviates in the direction of the opposite foot in a deformity in which the toe is also turned with the ball of the foot towards the contralateral foot and the nail of the toe in front to the second finger. It is a very spectacular alteration of the foot. The person who suffers from it has serious difficulties to put on and walk due to the biomechanical decompensation that this problem causes.
The hallux varus can appear even in newborns since in many cases it is due to a congenital cause. In other cases, the deformity is the object of a surgical sequel to the correction of hallux valgus.
Why is it produced?
The causes that produce hallux varus can be grouped into two categories:
Within the congenital causes we find two types of manifestations. The first is where we find the hallux varus deformity in isolation. The deformity appears alone without being associated with another congenital malformation.
An example of this type of manifestation is the abnormal insertion of the abductor hallux muscle that forces the finger to deviate into adduction, thus initiating the deformity.
The second type of congenital causes includes those manifestations in which we find hallux varus deformity associated with other congenital malformations such as metatarsus adductus, equinivarus foot, or neuromuscular disorders such as polio or teratogenic alterations.
Among the acquired causes we find joint subluxation as a result of chronic inflammation in processes such as rheumatoid arthritis or other systemic diseases.
Another acquired cause is the weakening or loss of function of the structures of the joint capsule, as is the case of accidents caused by sports practice in which direct trauma occurs on the first metatarsophalangeal joint.
The most common acquired cause within the acquired causes is hallux varus caused by postoperative sequelae of bunion surgery or hallux valgus. There are certain types of interventions that have a higher risk of producing hallux varus and are those that include any of the following procedures:
- Excision of the peroneal sesamoid.
- Excessive removal of first metatarsal head exostosis.
- Hypercorrection of bone deformity with decreased angle between the first and second metatarsals.
- Section of the tendon of the adductor pollicis muscle and the lateral portion of the first metatarsal head.
- Aggressive correction of joint capsule contracture.
- Hypercorrection of the postoperative bandage after hallux valgus surgery.
- Tibial sesamoid subluxation on adductor tendon transfer.
- All these actions within hallux valgus or bunion surgery can cause hallux varus deformity.
What symptoms appear?
The symptoms that accompany hallux varus deformity are:
- Deviation of the first toe in adduction. The big toe deviates towards the median axis of the body that passes just between the two feet. The big toe deviates in the direction of the opposite foot in a deformity in which the toe is also turned with the ball of the foot towards the contralateral foot and the toenail in front of the second toe.
- Alterations in the gait of the person due to the deformity. The first toe plays an important role in the development of the gait and this alteration prevents normal functioning due to the suppression of the impulse that the big toe makes during the removal of the foot from the ground during gait.
- Chafing, blisters, wounds or ulcerations caused by rubbing the toe with the shoe. This alteration makes it very difficult to put on because the deviation of the toe completely breaks with the normal shape of a conventional toe cap. In other types of foot deformities, such as bunions, it is easier for the patient to put the foot in the shoe, due to the looping of one toe against the other, but in the case of hallux varus this circumstance is possible. Only in flexible deformities can the foot be attached to the shoe.
- Hardness or calluses on the big toe or on the sole of the foot due to the friction of the shoe and
gait disturbances, which cause areas of overload and hyper-pressure.
- Alterations in the nail of the first toe. The nail can appear brittle or broken due to the friction of the shoe. If the trauma to the nail lasts over time, it can change shape, thickening due to alteration of the nail matrix. Continuous pressure on the growth area of the nail causes alterations in it.
- Pain and swelling in the joint.
- Muscle alterations and imbalances due to the incorrect functioning of the foot.
Diagnosis of hallux varus
Diagnosis of the deformity is made by clinical examination of the deformity and complementary diagnostic tests.
The indisputable complementary test is an X-ray of the affected foot. In it we can observe the degree of the deformity and the state of the adjacent structures. If the alteration has been caused by a postsurgical sequela, it is important to evaluate the state of the bone and joint elements to plan a good surgical correction.
Ultrasound and magnetic resonance imaging can be useful in congenital deformities to establish variations in the muscle and other soft parts of the foot that cannot be evaluated on radiography.
Treatment of hallux varus
Treatment of hallux varus is surgical in most cases. Only in cases of congenital deformities with sufficient flexibility is conservative treatment possible through the use of corrective splints.
The use of orthopedic insoles can help compensate for gait difficulties and avoid complications caused by this circumstance.
In elderly people or people with problems that contraindicate surgical intervention, it is important to assess the possibility of custom footwear that facilitates the fit of the foot without friction or discomfort.
In newborns or children, the deformity can be corrected by soft tissue surgery. These are surgical techniques that act only on muscles, tendons, ligaments, joint capsule and skin. Sometimes the deformity can be corrected without the need for bone manipulation.
On other occasions, the surgery must include corrections in the bone, both in the first metatarsal and in the phalanx of the big toe. It involves making wedge-shaped bone cuts that allow the osteoarticular structures to be repositioned to their original position.
How to avoid it?
If the causes of hallux varus are congenital, prevention is not possible, only being attentive to the development of the newborn to detect any deformity as soon as possible.
The appearance of a hallux varus acquired after a bunion intervention is something that many times cannot be controlled. In all surgery there is a small risk that must be assessed by weighing the “pros” and the “cons.” In this case the bunion surgery must be well programmed, well designed and well performed by the professional. The person intervened must follow the professional’s recommendations and thus the risks of the correction recurring or degenerating will be the lowest.
Hello Readers, I am Nikki Bella a Psychology student. I have always been concerned about human behavior and the mental processes that lead us to act and think the way we do. My collaboration as an editor in the psychology area of Well Being Pole has allowed me to investigate further and expand my knowledge in the field of mental health; I have also acquired great knowledge about physical health and well-being, two fundamental bases that are directly related and are part of all mental health.