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Acquired digital fibrokeratoma is a benign fibrous tumor usually located on the toes and fingers. A 63-year-old man with an acquired giant plantar fibrokeratoma is described. He presented with an asymptomatic exophytic nodule of ten years duration; there is no history of trauma to the site. It measured 15x10x5mm and was located on the plantar foot proximal to the third toe. Excisional biopsy established the diagnosis of fibrokeratoma. Giant acquired fibrokeratoma,has been described in 16 patients including ours: three women and 13 men. They are located on either the upper extremity (one man) or the lower extremity (15 individuals). Acquired plantar fibrokeratoma is rare. Including our patient, it has been reported in 11 patients: one woman and ten men. The woman was 13 years of age and the men ranged from 15 to 77-years-old. Plantar acquired fibrokeratomas are located on either the plantar aspect of the toes, the sole of the foot, or the heel. An excisional biopsy provided adequate treatment without subsequent recurrence of both giant and plantar fibrokeratomas.

Introduction  Hand and digit replantations can be complicated by vascular insufficiency necessitating revision of the original replantation. To date, few studies have evaluated outcomes in secondary revascularizations following replantation. Therefore, the objective of this study was to evaluate the incidence, etiology, and survival rates following secondary revascularization after hand and digit replantations. Materials and Methods  A literature search was performed on NCBI for studies documenting secondary revascularization procedures following hand and digit replant. Studies were evaluated for the etiology of vascular failure, frequency of secondary revascularization, and survival rates following intervention. Statistical analysis was conducted across the pooled dataset. Results  A total of 16 studies including 1,192 amputations were analyzed. We found that 16.9% (201/1,192) of replants were complicated by vascular compromise. The frequency of vascular compromise was not statistically different between arterial and venous etiologies. The survival rate following secondary revascularization was 55.6%, with no significant difference between the arterial and venous groups. Secondary arterial revascularization was often treated with arterial revision (nine of nine studies) and/or with vein grafting (two of nine studies). Secondary revascularization for venous insufficiency resulted in different survival rates for nonsurgical modalities (58%) versus vein revision (37.5%) versus vein grafting (100%). Conclusion  Survival rates following secondary revascularization are lower; however, they may be improved using vein grafts following venous insufficiency. These data can be used to better understand the etiology of replant failure and guide decision-making.

The combinatorial expression of Hox genes along the body axes is a major determinant of cell fate and plays a pivotal role in generating the animal body plan. Loss of HOXA13 and HOXD13 transcription factors (HOX13) leads to digit agenesis in mice, but how HOX13 proteins regulate transcriptional outcomes and confer identity to the distal-most limb cells has remained elusive. Here, we report on the genome-wide profiling of HOXA13 and HOXD13 in vivo binding and changes of the transcriptome and chromatin state in the transition from the early to the late-distal limb developmental program, as well as in Hoxa13-/-; Hoxd13-/- limbs. Our results show that proper termination of the early limb transcriptional program and activation of the late-distal limb program are coordinated by the dual action of HOX13 on cis-regulatory modules.

Hox genes play a critical role in the development of the vertebrate axis and limbs, and previous studies have implicated them in the specification of positional identity, the control of growth, and the timing of differentiation. Axolotl limbs offer an opportunity to distinguish these alternatives because the sequence of skeletal differentiation is reversed along the anterior-posterior axis relative to that of other tetrapods. We report that during early limb development, expression patterns of HoxD genes in axolotls resemble those in amniotes and anuran amphibians. At later stages, the anterior boundary of Hoxd-11 expression is conserved with respect to morphological landmarks, but there is no anterior-distal expansion of the posterior domain of Hoxd-11 expression similar to that observed in mice and chicks. Since axolotls do not form an expanded paddle-like handplate prior to digit differentiation, we suggest that anterior expansion of expression in higher vertebrates is linked to the formation of the handplate, but is clearly not necessary for digit differentiation. We also show that the 5' HoxD genes are reexpressed during limb regeneration. The change in the expression pattern of Hoxd-11 during the course of regeneration is consistent with the hypothesis that the distal tip of the regenerate is specified first, followed by intercalation of intermediate levels of the pattern. Both Hoxd-8 and Hoxd-10 are expressed in non-regenerating wounds, but Hoxd-11 is specific for regeneration. It is also expressed in the posterior half of nerve-induced supernumerary outgrowths.

Hox genes play a critical role in the development of the vertebrate axis and limbs, and previous studies have implicated them in the specification of positional identity, the control of growth, and the timing of differentiation. Axolotl limbs offer an opportunity to distinguish these alternatives because the sequence of skeletal differentiation is reversed along the anterior-posterior axis relative to that of other tetrapods. We report that during early limb development, expression patterns of HoxD genes in axolotls resemble those in amniotes and anuran amphibians. At later stages, the anterior boundary of Hoxd-11 expression is conserved with respect to morphological landmarks, but there is no anterior-distal expansion of the posterior domain of Hoxd-11 expression similar to that observed in mice and chicks. Since axolotls do not form an expanded paddle-like handplate prior to digit differentiation, we suggest that anterior expansion of expression in higher vertebrates is linked to the formation of the handplate, but is clearly not necessary for digit differentiation. We also show that the 5' HoxD genes are reexpressed during limb regeneration. The change in the expression pattern of Hoxd-11 during the course of regeneration is consistent with the hypothesis that the distal tip of the regenerate is specified first, followed by intercalation of intermediate levels of the pattern. Both Hoxd-8 and Hoxd-10 are expressed in non-regenerating wounds, but Hoxd-11 is specific for regeneration. It is also expressed in the posterior half of nerve-induced supernumerary outgrowths.