Published papers

Summary: Congenital brachymetatarsia most commonly involves the fourth ray and may be combined with metacarpal shortening. Now, many reports demonstrated the usefulness of distraction osteogenesis for lengthening of the metatarsals by using an external distraction device. In this article, we treated shortening fourth metatarsal by bone lengthening using the internal distraction device. This technique has some advantages over the method of external distraction.

Background: Capsular contracture is a common complication after breast augmentation surgery. This study pathologically evaluated the soft-tissue response to surface modifications in both smooth and textured tissue expander prostheses. Methods: Smooth tissue expanders and textured tissue expanders in 5 cases each were used for breast reconstruction after mastectomy. Histological samples were harvested from the capsules when the tissue expanders were replaced by silicone implants. Collagen orientation and cellular responses were assessed histologically. Capsular contracture was evaluated using the Baker classification 6 months and 2 years after the removal of the tissue expander. Results: The capsules surrounding the smooth tissue expanders tended to produce more contracture than those surrounding the textured tissue expanders. The collagen architecture of the capsules of the smooth tissue expanders showed random orientation with fragmentation. Conversely, the capsules of the textured tissue expanders showed parallel orientation with collagen bundles of almost normal structure. Significantly more fibrils of elastin and myofibroblasts were found in the capsules surrounding the smooth tissue than in those surrounding the textured ones. Conclusions: The collagen fibers surrounding the smooth tissue expanders could be cracked during expansion, which may lead to scarring and contracture. Conversely, the collagen orientation surrounding the textured tissue expanders was excellent. Moreover, the increase in elastic fibers and myofibroblasts in the capsules surrounding the smooth tissue expanders may be associated with in vivo contraction patterns. Therefore, the surface type of tissue expanders affects capsular contraction after replacement with definitive implants.

Summary: YAP (yes-Associated protein) and TAZ (transcriptional coactivator with PDZ-binding motif) are part of a classical pathway that controls contact inhibition in the Hippo pathway. YAP and TAZ were recently reported to act as nuclear relays of mechanical signals that communicate extracellular matrix rigidity and cell shape. However, the role of YAP/TAZ signaling in keloid formation is unclear. Here, we used immunohistochemistry to investigate YAP/TAZ expression in keloid and nonaffected lesions. YAP/TAZ expression in keloid fibroblasts had a greater tendency to localize to the nucleus relative to that seen in fibroblasts from unaffected tissues. Meanwhile, keratinocytes or endothelial cells from either keloid or unaffected tissues showed no significant differences in YAP/TAZ expression patterns. These results suggest that YAP/TAZ nuclear localization in keloid fibroblasts might activate Hippo signaling and may play an important role in gene expression that affects keloid formation and stiffness.

Background: In breast reconstruction using a tissue expander (TE), sufficient coverage of the TE with the pectoralis major (PM) muscle, particularly with a musculofascial flap, is highly important for avoiding postoperative complications. In patients in whom the PM is thin, intraoperative trauma often occurs, leading to troublesome repair. The present study aimed to investigate the usefulness of preoperative measurement of PM thickness in planning of breast reconstruction using a TE. Methods: In this case–control study, we identified 68 patients (70 breasts) with mammary carcinoma treated with simple mastectomy and TE insertion from April 2014 to December 2016. We measured average PM thickness at two specific points, sternocostal PM distance on the long axis and sternocostal PM area preoperatively using magnetic resonance imaging. Then, we analyzed the difference in PM thickness among individuals and its relationship to intraoperative trauma to the PM or surgical difficulty creating a muscular pocket (delicate PM). Results: Average PM thickness was significantly larger in younger patients (p = 0.046) and those with larger breasts (p < 0.01). In addition, average PM thickness on the affected side was significantly smaller in patients with delicate PM (12 breasts) (p < 0.01). PM thickness had a significant influence on delicate or firm PM (odds ratio 27.40; 95% confidence interval 2.01–372.00; p = 0.013). Conclusion: These findings demonstrate the usefulness of preoperative measurement of PM thickness in planning of breast reconstruction using a TE. Dissection should be performed more carefully in patients with average PM thickness less than 2.9 mm.

Purpose: In order to prevent postoperative infection and recurrence of sacrococcygeal pilonidal sinus, the authors developed a modified Dufourmentel flap, involving the superior pedicles, and designed a descriptive prospective study to evaluate its efficiency. Methods: Between July 2007 and March 2014, 16 patients with sacrococcygeal pilonidal sinus were treated with an irregular quadrilateral excision and reconstruction by a modified Dufourmentel flap with superior pedicle. The duration of wound healing, presence of wound complications and permanent hypoesthesia, and recurrence rates were recorded and assessed. Results: None of the patients developed flap necrosis or wound infection postoperatively. The duration of wound healing was 7.2 ± 2.9 (range = 6–15) days. Wound dehiscence was demonstrated in only one patient (6.3%). The mean follow-up period was 4 years and 2 months (range = 4 months–8 years and 8 months), whereby no permanent hypoesthesia or recurrence was detected. Conclusion: The modified Dufourmentel flap with superior pedicle can be safely used as a treatment of sacrococcygeal pilonidal sinus, with excellent results.

Facial scars are common and cause functional problems and psychological morbidity. Recent advances in optical technologies have produced various laser systems capable of revising the appearance of scars from various etiologies to improve their appearance. Scar management with laser devices is optimized when individual patient and scar characteristics are thoroughly evaluated to determine the best course of treatment. Because scars have a variety of potential etiologies and take a number of forms, no single approach can consistently provide good scar revision. The combined use of various laser devices is essential, and the choice of wavelength and approach are individualized for each patient. In this manuscript, we introduce the concept of scar management with laser devices and the use of various laser systems such as low reactive-level laser therapy (LLLT) for symptomatic scars with inflammation, pulsed-dye laser irradiation for scars with inflammation and telangiectasia, and fractional laser resurfacing, with presentation of representative cases.

Background: In mandibular reconstruction with vascularised free fibula transfer, there are situations where the neck on the operated site lacks recipient vessels for vascular anastomosis due to previous radiological/surgical interventions. Methods: The present study aims to clarify the availability of neck vessels on the contralateral side in such situations. Experimental surgery was conducted on 20 fresh cadavers (six males and 14 females). After the left half of the mandible was removed, free vascularised fibula of equivalent length was transferred to fill the defect. The possibility of connecting the peroneal artery and vein to the superior thyroid artery (STA), transverse coli artery (TCA), internal jugular vein (IJV), and external jugular vein (EJV) of the contralateral side was evaluated. Results: In all samples, the peroneal vessels could reach the STA and EJV. However, the peroneal vessels could reach the TCA and IJV of the contralateral side in only 45% and 64.2% of cases, respectively. The average and standard deviation of the lengths by which vessels were insufficient were 1.1 ± 13.9 mm for IJV and 8.8 ± 24.7 mm for TCA. Conclusions: In reference to these findings, it is concluded that, in situations where neck vessels of the defect side are unavailable, availability of the superior thyroid artery and external jugular vein should be examined first. When these vessels are available as recipient vessels, direct vascular anastomosis is highly likely to be successful. In cases where these vessels are unavailable and the transverse coli artery or internal jugular vein is used as the recipient, vascular interposition might be necessary.

Background: Distally based flaps are useful for the treatment of skin defects of the extremities. However, congestion in the peripheral part of the flap due to reverse flow can cause partial flap necrosis. Previously, we reported on the effectiveness of venous anastomoses to rescue peripheral congestion of distally based flaps and applied this idea in a clinical setting. In this report, we present clinical cases of distally based flaps with venous supercharge anastomoses for changing the reverse venous flow into physiological flow, thereby reducing venous congestion. Methods: Four patients with skin defects of the extremities (2 cases with defects of the knee and the upper third of the lower leg, 1 case of the lower third of the lower leg, and 1 case of the distal third of the forearm) were treated with local flaps (2 cases with distally based greater saphenous venoadipofascial sartorius muscle combined flaps, 1 case with a distally based lesser saphenous venoadipofascial flap, and 1 case with a distally based ulnar artery perforator flap). In each reconstruction, 1 or 2 veins in the flaps were anastomosed with superficial veins in the recipient area to change the reverse venous flow into a normal, physiologic flow. Result: All flaps healed completely without any obvious venous congestion or flap necrosis. The coverage quality provided by these defects was satisfactory. Conclusions: Adding venous anastomoses may reduce the risk of venous congestion and improve the outcomes of the distally based flaps.

Background: The goals of successful palate repair include optimization of speech and feeding, avoidance of fistula formation, and mitigation of adverse maxillary growth. However, the effects of scar formation on maxillary growth have not been discussed in detail. Methods: Between November 2010 and December 2011, the palateplasty was performed for 24 patients with cleft palate (median age, 12 months; range, 11-18 months). In the velum, a symmetrical intravelar veloplasty with mucosal Z-plasty was performed on both the nasal and oral sides. In the hard palate, instead of lateral relaxing incisions, a 1-line mucoperiosteal incision along the cleft margins was designed with subperiosteal undermining in the entire palatine bone. The palatal mucoperiosteum was sutured together in the middle of the cleft, and the cleft was directly closed without lateral relaxing incisions. The patients were monitored for 6 months to 1.6 years. Results: None of the cases had issues concerning flap viability, and all palate repairs healed well. Postoperative results were satisfactory, without any complications such as dehiscence, perforation, or palatal fistula. Conclusions: The method presented in this article was effective, with successful palatal closure and without scar formation or mucosal defects along the alveolus. We conclude that minimum contracture of the hard palate was useful for not only mitigating adverse maxillary growth but also for orthodontics.

Isolated dermal cells possess the capacity to induce hair growth. The cells cannot be expanded while they retain the capacity for hair induction, and lose their potential immediately after cultivation. Sphere-forming multipotent cells derived from the dermis (skin-derived precursors [SKPs]) possess hair-inducing activity. These observations provide two possibilities for the determination of the capacity for hair induction: capacity is dependent on either identity as a dermal cell or on the process of sphere formation. We developed a method that demonstrates cultivated mesenchymal cells derived from dermis and lung tissue possess in vivo hair-inducing capacity via sphere formation.

Background: Various types of sternum defects are produced after the removal of thoracic tumors involving the sternum. The present study aims to elucidate the relationship between the defect patterns and their effects on thoracic respiration. Methods: Ten sets of finite element models were produced simulating thoraces of 10 persons and termed normal models. With each of the 10 normal models, the sternum was removed in six different ways to produce new models termed defect models. Defect models were categorized into hemi-superior (H-S), hemi-inferior (H-I), hemi-whole length (H-W), bilateral-superior (B-S), bilateralinferior (B-I), and bilateral-whole length (B-W) defect types, depending on the locations of the defects. Respiratory movement was dynamically simulated with these models. The volume change the thoraces present during respiration was measured to evaluate the effectiveness of thoracic respiration. This value - defined as ΔV - was calculated and was compared between normal and defect models. Results: With H-W and B-W type models, ΔV dropped to around 20% of normal values. With H-S and B-S type models, ΔV dropped to around 50% of normal values. With H-I and B-I type models, ΔV presented values almost equivalent to those of normal models. Conclusion: Effectiveness of thoracic respiration is seriously impaired when the whole length of the sternum is absent. Reconstruction of the defect is essential for these cases. However, since the upper part of the sternum is most important for effective thoracic respiration, priority should be placed on the upper part in performing reconstruction.

Introduction: Patients with fronto-orbital fibrous dysplasia (FD) occasionally present fronto-orbital protrusion, exophthalmos, and visual acuity disturbance. Simultaneous management of these conditions has not been previously described. Case description: A-10-year-old female with fronto-orbital FD complained of left visual acuity disturbance. Head computed tomography showed compressed optic canal secondary to thickened bone. Decompression of the optic canal via the left frontotemporal extradural approach, opening of the lateral orbital wall, and dissection of the prominent zygoma were done simultaneously. The patient’s visual acuity disturbance and exophthalmos subsequently improved postoperatively. Discussion and evaluation: When optic canal decompression is performed by the fronto-temporal approach, opening of the lateral orbital wall can be done simultaneously to decrease the intraorbital pressure and to prevent exophthalmos. In addition, although aesthetic plastic surgery is not generally recommended during the growing phase (due to the possibility of recurrence), this approach can prevent skin loosening and adverse cosmetic outcomes. Conclusions: Aesthetic plastic surgery for fronto-orbital FD is recommended to prevent skin loosening. Opening of the lateral orbital wall should be performed when optic canal decompression is planned.

The use of human vessels at the beginning of microsurgery training is highly recommended. But vessels with the appropriate length for training are not often obtained. Whether these vessels may be reused for training has not been reported. Accordingly, we harvested vessels from discarded tissues in lymph node dissection and demonstrated that vascular anastomosis training using the same human vessels several times is possible by placing the vessels in a freezer and defrosting them with hot water. Vascular walls can be stored for microsurgical training until about 4 years after harvest, as shown in the gross appearance and histologic findings of our preserved vessels. We recommend the technique presented here for the longterm reuse of human vessels for microsurgery training that closely resembles real procedures.

Adjuvant chemotherapy and anti-estrogenic therapy can result in decreased volume of the contralateral breast, following mastectomy for the treatment of breast cancer. However, no data on the effect of adjuvant therapy on contralateral breast volume have previously been reported. We aimed to evaluate the extent to which adjuvant therapy and differences in breast density contribute to decreased breast volume.We conducted a prospective cohort study, selecting 40 nonconsecutive patients who underwent immediate breast reconstruction with mastectomy and expander insertion followed by expander replacement. We measured the contralateral breast volume before each procedure. The extent of the change was analyzed with respect to adjuvant therapy and breast density measured by preoperative mammography.The greatest decrease in breast volume was 135.1 cm3. The decrease in breast volume was significantly larger in the adjuvant therapy (+) group, particularly in patients with high breast density, than in the adjuvant therapy (-) group. Significant differences between the chemotherapy (+), tamoxifen (+) group and the chemotherapy (-), tamoxifen (+) group were not found. Breast density scores had a range of 2.0-3.3 (mean: 2.8).In breast reconstruction, particularly when performed in one stage, preoperative mammography findings are valuable to plastic surgeons, and possible decreases in the contralateral breast volume due to adjuvant therapy, particularly in patients with high breast density, should be considered carefully.

Mammalian fetal cutaneous wounds made at certain developmental stages show complete regeneration. It is reported that wound healing in both adult and fetal skin is disrupted by denervation. Furthermore, fetal cutaneous regeneration has unique aspects such as epidermal wrinkle texture regeneration and dermal regeneration that depend on developmental stage. Therefore, we have examined the relationship of fetal cutaneous regeneration with denervation. We made cutaneous wounds on fetal mice at various developmental time points including embryonic days (E)13, E15, and E17, and compared the regenerating patterns of peripheral nerves in the skin. We found that when the fetuses are wounded at an early stage of development, peripheral nerves regenerate quicker than at later stages of development when peripheral nerve regeneration is delayed. Next, we denervated the intercostal nerves and made wounds at the denervated sites on E13 and E15. We found that epidermal wrinkling and dermal regeneration were disrupted by denervation. These findings indicate that components of fetal cutaneous regeneration and peripheral nerve regeneration are mutually dependent.