Every podiatrist and other foot care specialists no doubt are familiar with the common ingrown toenail of the great toe. Thousands of nail avulsions are performed successfully daily on a routine basis across the globe with very few complications. Oftentimes this ubiquitous malady is approached with very little thought due to its straightforward nature. Moms will blame their children for picking at their toenails, or someone will say their shoes are too short. Frequent fungal infections or other onychodystrophy conditions may be present. Often overlooked, however, there may be underlying biomechanical basis for a a acute or chronic ingrown toenail, thus presenting an opportunity for a biomechanically astute practitioner to delve deeper into the causation of this pathology and provide a deeper level of treatment including a more holistic approach to the patient attached to that nasty toenail. You will not only correct the problem by surgical or non-surgical means, but proactively identify, evaluate and address additional biomechanical conditions that may be also present.
The human foot is a marvel of engineering. Our ability to walk upright on two feet and progress forward in space in an efficient manner is largely dependent on the propulsive force generated at the level of the 1st metatarsal phalangeal joint. The strong posterior calf muscle contracts to raise the heel off the ground, simultaneously the opposite limb ankle extensors are firing to decelerate ankle plantarflexion at heel contact. The great toe is fixed against the ground, as the 1st metatarsal bone increases its angle relative to the ground, resists the ground reactive force and slides posteriorly on the sesamoids until adequate range of motion has occurred to then enter the toe off phase. This intracic set of movements must repeat thousands of times each day to just successfully walk down the street. In a perfect world, this would occur with robotic efficiency. However, any slight deviation may result in a pathological force which, if repeated enough, may lead to a visit to the foot doctor, including the dreaded corrective nail procedure.
Ingrown toenails may occur on either the medial border, lateral border, or both borders simultaneously. Normally, during the propulsive phase the line of force of weight bearing goes directly through the distal portion of the great toe. However, if a functional limited range of motion of the first metatarsal phalangeal joint occurs due to reactive ground force, the great toe has a tendency to rotate on the frontal plane in a valgus direction or on the transverse plane in an abductory direction, thus causing an impingement of the nail folds on one or both sides of the great toenail. Many times,repeated often enough, and possibly exacerbated by other factors such as ill fitting shoes, or nail plate pathology, ingrown toenails result.
Many patients will appreciate a deeper dive into the causation of their minor, but debilitating ingrown toenail. Discussing the mechanics of the foot and other ramifications of a dysfunctional propulsive mechanism of the 1st MTPJ and recommended treatment, above and beyond simply correcting the ingrown toenail demonstrates a more holistic and proactive approach to a common foot condition.
