Acquired Congenital Malalignment of the Great Toenails

Abstract

Congenital malalignment is the lateral deviation of the nail plate along the longitudinal axis due to the lateral rotation of the nail matrix. The nail plate grows out in ridges caused by repeated microtrauma to the nail. Common complications include onychomycosis, Pseudomonas infection and acute or chronic paronychia. Treatment options range from conservative management to surgical options including realignment and nail matrixectomy. Congenital malalignment usually presents in infancy or childhood, but we present two cases of acquired malalignment occurring in the teenage years.

Congenital Malalignment of the Great Toenails: A Review

“…The age at onset was at birth in 25 cases [2, 9, 10-13, 15-18, 21, 22, 24, 25], during the first 2 years of life in 2 cases [2, 20], and later in life in 2 cases [19], whereas it was not specified in 4 cases [3, 8, 14, 23]. Familial occurrence was confirmed in 5 cases [10, 12, 14, 18], likely in 2 cases [11], and negative in 9 cases [2, 13, 15, 16, 25], whereas in the remaining ones it was not specified [3, 8, 9, 17, 19-24]. Three sets of monozygotic twins [11, 21], 2 of dizygotic twins [12, 16], and 2 identical twins of triplets [13] were reported.…”

“…Clinically, congenital malalignment of the toenail was usually characterized by lateral deviation of the nail plates, which were not parallel to the distal phalanx, as seen in 30 cases [2, 3, 8, 10-17, 19-25, 28]; medial deviation has rarely been observed, with only 3 cases reported [9]. As regards the localization, the disorder more commonly and synchronously involved both great toenails, as observed in 29 cases [2, 3, 8, 10-25]; in 1 case, one toenail only was affected [25], and in 3 cases the localization was not specified [9].…”

“…As described in Table 2, nail plate thickening [8-12, 14, 16, 19, 22-25], discoloration ranging from brownish-black to green-brown and yellow [2, 8, 10, 11, 14, 16, 18, 19, 25], and transversal grooves or ridges [2, 8, 10, 11, 16, 23-25] were the most frequently observed abnormalities. The involved nails were sometimes shorter and trapezoidal in shape [2, 22, 23].…”

“…It has also been suggested that a key role in the pathogenesis of toenail malalignment is played by an increased tension of the extensor tendon of the hallux, which, by pulling the lateral portion of the matrix proximally, may cause a lateral rotation of the nail matrix, and, hence, a longitudinal displacement of the nail plate axis [12]. A recent hypothesis suggests that the pathogenesis may be due to desynchronization in growth between the nail and the distal phalanx of the hallux, resulting in larger nail plates, which must grow laterally to fit into the underlying bony space [12, 19]. It is also possible that the dystrophy is due to the genetically determined malalignment of the toenails plus superimposed cumulative effects of postnatal trauma [21, 26].…”

“…Generally the condition is present at birth, but, in case of minimal deviation, it may go unnoticed until childhood or puberty, when nail dystrophic changes occur as a result of mechanical stress, due to wearing tight shoes or to activities such as dancing or active sports [2, 19, 25]. As very few data on long-term follow-up are available, the exact percentage of spontaneous realignment is unknown, although it has been suggested to occur in about one-half of the patients before the age of 10 years [25].…”