A Unique Case of Crossover Second Toe Syndrome treated by Autologous Peripheral Blood Stem Cells

Abstract

There have been many clinical designations for crossover second toe deformity, including plantar plate tears, hammertoe, metatarsalgia, predislocation syndrome and metatarsophalangeal joint (MPJ) instability. However, the crossover second toe is a common and high problematic case of foot and ankle. Mostly, the issue is associated with some form of progressive bone metabolic degenerative condition as deforming arthritis that ends with a multitude of forefoot deformities. Although multiple theories have been suggested, the true underlying cause of the deformity is multifactorial and only some of these factors have been scientifically analyzed and clarified. Thismakes the situation more problematic as the procedure requires to treat associated bone deformities, tendinopathies and neuropathies all at the same time in order to achieve a good outcome. Anatomically and pathologically this condition is a result of few condition such as the aging process, the gradual deprivation of bone structure consequently of metabolic disorders and a chronic inflammatory state as result of a prolonged increasing of medial pull of the flexor apparatus effects in rupture or attenuation of the lateral collateral ligaments of the second MPJ complex with valgus tendency exacerbating the underlying problem and inflammation. A second co-deforming force is the dorsal pull of the long and short extensor tendons without opposition from the plantar plate resulting in a hammertoe deformity with dorsal contracture or dislocation of the toe at the MPJ. Therefore it’s essential to consider soft tissue deformity together with osseous deformity in crossover second toes. Inevitably, those who treat the condition commonly note there is a long metatarsal associated with the deformity with presence of tear to the plantar soft tissue structures together with prolonged periods of high peak pressures during walk.
An adjunctive concern is due to hypermobility of the first ray linked with elevated pressures  from plantar to the second metatarsal head region. The direct pressure coupled with adductus of the hallux, which may cause dorsal displacement of the second toe, may be also be one of the basic causes of the crossover second toe.We reported a case of a 56-year-old woman presented to our formation with multiple joint osteo-arthritis with painful swelling on shoulders, bilateral knees, lower back, ankles with a visible bilateral cross over second toe condition. An MRI and X-ray were performed, and objectified a multiple osteoarthritis and grade 4 dual cross over second toe syndrome with deformity associated with hallux valgus, hallux rigidus, neuroma of the third intermetatarsal space with metatarsus sub-luxation. The patient received a treatment of autologous PB-SCs infusion during a period of 3 weeks, the results showed a complete recovery of cross over second toe condition on both left and right foot.