Case Report
Ciro Gargiulo, Van H Pham, Kie
Abstract
Plantar plate tears, hammertoe, metatarsalgia, predislocation syndrome and metatarsophalangeal joint (MPJ) instability, all refer to what is commonly known as crossover second toe syndrome (CST). The CST, despite being widely present in the population, is a highly problematic condition that involves the entire structure of the foot and ankle including bones, muscles, tendons and joints. The CST is a form of degenerative condition associated with a progressive metabolic degenerative arthritis or arthrosis that leads to multiform forefoot deformities. Although the real underlying cause of the deformity is multifactorial, only some of the leading factors have been scientifically clarified, which make the prognosis quite problematic as the procedure needs to be proceeded on different levels and plans just to achieve an acceptable outcome, due to bone deformities, tendinopathies and neuropathies. Anatomically and pathologically, this condition is the result of the aging process, gradual deprivation of bone strength and a chronic inflammatory state induced by prolonged divergent and asymmetric mechanical forces of muscles and tendons. A strong pull of the flexor tendon medially and/or the attenuation of the lateral collateral ligaments of the second MPJ complex with valgus tendency related to a dorsal pull of the long and short extensor tendons without opposition from the plantar plate will result in a hammertoe deformity with dorsal contracture or dislocation of the toe at the MPJ. It has also been found that a long metatarsal together with prolonged periods of high peak pressures during walking are associated with the deformity and tears at the site of the plantar soft tissue. An adjunctive concern is caused by the hypermobility of the first ray linked with elevated pressures from the plantar to the second metatarsal head region. The direct pressure together with adducts of the hallux may cause dorsal displacement of the second toe. A case of a 56- year-old woman was presented to us with multiple joint osteo-arthritis and painful swelling on shoulders, bilateral knees, lower back, and ankles with a visible bilateral crossover second toe condition. An MRI and X-ray were performed, objectified a multiple osteoarthritis and grade 4 dual crossover second toe syndrome with deformity associated with hallux valgus, hallux rigidus, and neuroma of the third intermetatarsal space with metatarsus subluxation. The patient received a treatment of autologous PB-SCs infusion during a period of 3 weeks; the results showed a complete recovery of crossover second toe condition on both left and right foot.