Balance and gait problems increase the risk of falls in the population, which can have serious consequences. Good foot support is essential to reduce these risks. There are many pathologies of this organ that affect its balance, highlighting those that are directly related to the so-called first radius of the foot (first wedge, first metatarsus, first proximal phalanx and first distal phalanx) as well as with the plantar arch. Among many others, hallux limitus and acquired flat feet in adults (AFFA) aggravated by supination can be highlighted.
Hallux limitus is a degenerative process that continues over time to a progressive loss of movement and increased pain with associated disability in walking. It is a pathology that usually goes unnoticed in the initial stages, ending, in most cases, in hallux rigidus. Early detection of this pathology would save pain for the patient and expense for the health system. Various actions are known to combat this pathology, non-invasive (orthopedic insoles) and invasive, such as the insertion of an implant in the first metatarsophalangeal joint.
AFFA, in advanced stages, produces a great imbalance when it comes to the patient's gait. In most cases of AFFA in these advanced stages, a surgical technique is usually imposed that rarely requires a single isolated procedure, but rather a selection of techniques. Among these techniques, the Cotton osteotomy occupies an important place. It is a medial cuneiform wedge osteotomy with a dorsal opening without, to date, a preoperative guide that can predict the size of the graft or the type of material to be grafted.
The project presented exhibits a double objective in the search for new solutions in pathologies associated mainly with the first ray of the foot, and in particular those related to hallux limitus and AFFA. The first objective is, on the one hand, to facilitate the early detection of hallux limitus (which, as has been indicated, is not usually detected until it leads to another more pronounced pathology) and, on the other hand, to evaluate the effects that it has on the bone and Other foot tissues have the insertion of an implant. In particular, the effect that an implant produces on hard and soft tissues at the level of tensions and deformations will be studied, placing special emphasis on the bone remodeling processes that occur. The second objective is to provide the surgeon with a tool that allows him to know with greater certainty (and not only due to his level of experience) the degree of correction that he must perform when carrying out a Cotton osteotomy.
Both objectives will be achieved, mainly, through the creation of finite element computational models. In the case of hallux limitus, a pathological model of this disease will be created that can determine the variations that occur in the healthy foot at the level of tensions and displacements in the hard and soft tissues of the foot. From this, the effect of the inclusion of implants can be evaluated.
In the case of AFFA, a model with varus flat feet will be created, so that the Cotton osteotomy can be simulated at various levels and with various graft construction materials in order to guide the surgeon in his decision making.