We describe a percutaneous technique for screw fixation of all types of fractures of the scaphoid. During a 15-year period ending in 1984, 280 cases were treated by this method; 198 of them returned for evaluation in 1986 and comprise the material for this report. After a mean postoperative time of 82 months, 89% of the recent fractures had united as well as 81.8% of those with delayed or nonunion and 42.8% of those with sclerotic nonunion.

Studies of human hair follicle (HF) induction by follicle-derived cells have been limited due to a lack of suitable test systems. In this study, we established a skin organ culture system which supports HF formation by follicle-derived cells. Long-term skin organ cultures were set up from human retroauricular skin specimens and maintained in culture for up to 8 weeks. In vitro expanded human HF-derived cells from the dermal papilla (DP) and the outer root sheath (ORS) were injected together into the skin specimens and evaluated for their ability to induce reorganization of HFs. Macroscopic analysis of the cultured skin specimens demonstrated the growth of velus-like hair after 4 weeks in culture. Histologic evaluation of the cultured skin specimens after 8 weeks of culture revealed multiple miniaturized HFs with sebaceous glands. In addition, cell clusters of various differentiation stages could be demonstrated in serial sections of the cultured skin specimens. Labeling of HF-derived cells with the fluorescence dye CFDA-1 prior to injection suggested a de novo reorganization of HFs out of the injected cells. In conclusion, the study demonstrated HF formation by HF-derived cells in an in vitro skin organ culture model.

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Background and Objectives: Micrograft transplantation is accompanied by a transient induction of telogen in transplanted hair follicles (HF), which might be avoided by supporting the metabolic pathways of the micrograft during the ex vivo period. Vitamin B 12 (cobalamin) has been suggested to influence HF growth and cycling in humans, but the mechanisms are unclear. Method: HFs were obtained from patients undergoing routine micrograft transplantation and were cultured for 5 days in Dulbecco's modified Eagles Medium, supplemented with different amounts of vitamin B 12. Hair shaft elongation (HSE) of the isolated HFs as well as quantitative changes of mRNA for -catenin, glykogensynthase kinase-3 (GSK-3) and TCF/Lef-1 in HF cells were determined. Results: In vitro HSE demonstrated a dose dependent induction of HSE after stimulation with 2.5 g/ml and 25 g/ml vitamin B 12 (6.2  2.1% and 15.4  3.8% respectively). A dose dependent induction of -catenin-mRNA could be demonstrated in cultured HFs after stimulation with 2.5 g/ml and 25 g/ml vitamin B 12 (fold change compared to DMEM: 9.5  2.7, p < 0.05 and 23.1  7.4, p < 0.01; respectively). Concomitantly the amounts of GSK-3 were significantly reduced after stimulation with 25 g/ml vitamin B 12 (fold change compared to DMEM: 0.76  0.12, p < 0.05). Conclusions: Our data demonstrate a hair growth promoting effect of vitamin B 12 in vitro. This effect is accompanied by the modulation of intracellular signal transduction molecules of the wnt-pathway and might promote hair growth after micrograft transplantation.

Our study demonstrated an important role of ACD in micrograft transplantation surgery. Preconditioning of micrografts with storage buffers containing inhibitors of ACD could prevent serum-induced ACD after transplantation and might increase the viability of micrografts and the clinical outcome in micrograft transplantation.