Classification of Achilles tendon shortening induced by scar contracture and corresponding treatment strategies for pediatric patients - A single unit experience.

BACKGROUND: Achilles tendon shortening of pediatric patients caused by scar contracture poses a challenge for us. It always impairs walking function. In this article, we attempted to introduce a new classification of Achilles tendon shortening of pediatric patients and corresponding treatment strategies in our single center. METHODS: From 2001 to 2018, 65 patients (aging from 13 to 17-years-old, 34 females and 31 males, 21 cases with unilateral Achilles tendon shortening and 44 cases with bilateral Achilles tendon shortening) were recruited. The causes included trauma (n = 13), scald (n = 20) and burn (n = 32). The distance between the heel and the ground was from 3 to 18 cm. They were classified into three types: ≤5 cm, mild, n = 9; 5-10 cm, moderate, n = 30; ≥10 cm, serious, n = 26. They had a history from 7 months to 4 years (28 cases with less than 1.5 years and 37 cases with more than 1.5 years). Treatment methods: Scar-Achilles-Tendon (SAT) flaps and skin graft were used for moderate cases before special external fixation shoes were used for fixation for at least 6 months. External special shoes fixation was used for mild cases except 5cases still received SAT flap and skin graft. In serious cases, bone extraction was used for at least 6 months before receiving SAT flap and skin graft. RESULTS: The distance between the heel and the ground was 0 cm after treatment in 54 cases (mild, n = 9; moderate, n = 28; serious, n = 18). Recurrence was found in 11 cases (mild, n = 0; moderate, n = 5; serious, n = 6) after six months follow-up. There were 13 cases of tangential excision of eschar and 8 cases of escharectomy (P < 0.05) with flap necrosis affection. Among them, 9 cases with a medical history of less than 1.5 years had partial necrosis, 6 cases with a medical history of more than 1.5 years had partial flap necrosis(P < 0.05). Local necrosis was covered by skin graft again. Bone exposure was found in 5 serious cases. It was repaired by negative pressure therapy first and then skin graft was used. The walking ability (P < 0.05) and function (P < 0.05) of lower limbs were statistically improved after treatment. CONCLUSIONS: Different methods can be used according to the shortening degree of Achilles tendon of pediatric patients based on the new classification, which may be useful for future clinical work.

A comprehensive reconstruction strategy for moderate to severe faciocervical scar contractures.

The focus of treatment of faciocervical scar contractures includes cervical reconstruction and elimination of hypertrophic scars. Unfortunately, most previous studies have neglected the esthetic appearance of scars. In this study, we tried to combine surgical therapy and ultrapulse fractional CO2 laser (UFCL) to eliminate facial scars while restoring neck reconstruction and to establish the optimal conventional management for faciocervical contracture. Thirty-eight individuals were enrolled and divided into two groups. After received cervical release surgeries, comprehensive UFCL therapy group received treatment of UFCL at 3-month intervals, silicone sheets, and pressure garments, while another group only received treatment of silicone sheeting and compression. Twelve months after the termination of therapy, faciocervical scars of both two groups were assessed by two uninvolved physicians according to the Vancouver Scar Scale (VSS), and patients' satisfaction survey was also recorded by the study participants using a patient four-point satisfaction scale. Thirty-six patients completed the treatment and follow-up. The results show that the VSS scores of both two groups decreased after 12 months, but comprehensive UFCL therapy group dropped more significantly than the conventional treatment group at follow-up session, which was statistically significant (P < 0.001), and the patient satisfaction was higher than that of the conventional treatment group. This comprehensive treatment combined of surgery, UFCL, silicone sheets, and pressure garments works as an effective and esthetic reconstruction for moderate to severe postburn faciocervical scar contractures.

Using rational strategies for children's scars based on more than 5 years assessment after burn.

BACKGROUND: Paediatric patients with scars after burn are regularly encountered. Discussion of rational strategies for management are of value. The objective of the study was to describe development and utilisation of strategies for paediatric burn scars up to five years after injury. METHODS: We included 164 cases aged from 5 to 8 years old in our study; all had burn scar deformities. RESULTS: Assessments were made up to December 31, 2019. The following strategies were used: sequential treatment, reconstruction based on facial aesthetic units, predicting the effect of surgery on development, releasing skin tension and application of photoelectric technology or other non-surgical measures. CONCLUSIONS: Using rational strategies for paediatric burn scars is very important.

Combination therapy of refractory keloid with ultrapulse fractional carbon dioxide (CO2 ) laser and topical triamcinolone in Asians-long-term prevention of keloid recurrence.

Keloid often recur after treatment, and recent studies in keloid management favor the combination therapy of laser-assisted drug delivery over monotherapy. Unfortunately, the previous researches lack long-term follow-up. In this prospective study, 41 individuals with refractory keloids underwent eight treatment sessions at 4 weeks intervals consisting of ultrapulse fractional carbon dioxide laser (UFCL), followed by postoperative application topical triamcinolone acetonide (40 mg/ml). Four follow-up moments were chosen, with follow-up of 24 months. The effects of combination therapy on scar pliability, thickness, relief, vascularization, surface area, pain, and itchiness were examined by means of the Patient and Observer Scar Assessment Scale (POSAS). 38 patients completed the full 24 months of follow-up after the whole treatment. The results reveal a fast and abiding improvement of keloid scars after the combination therapy. The mean keloid POSAS scores showed a decreasing trend in subsequent times. All POSAS components improved significantly between baseline and 24 months after start of therapy (P < .05). Long-term follow-up results demonstrate that combination keloid therapy using UFCL and tropical triamcinolone has overall significant improvement and low recurrence rate with a long-term stable results.

Analysis of Factors Affecting Chronic Ulcers of Scalp Transforming Into Marjolin's Ulcer: A Single Center Experience.

The Marjolin's ulcer (MU) is a rare malignant lesion, which is characterized by primary, chronic wound initially and formation of cancer after a certain incubation period eventually. Though few reports or a small case series about MU on the scalp have been published, special risk factors are still unknown about the formation of malignancy on the scalp with chronic ulcer. The aim of the article is to explore the risk factors. Seventy-four patients with the chronic ulcer were included in the study. In between, the chronic ulcer transformed into the MU on the scalp (tumor group) in 42 cases, while the chronic ulcer did not transform into the MU on the scalp (tumor-free group) in 32 cases as controlled group. We made a comparative study between the above two groups so as to find which risk factors were critical for cancer development. In tumor group, lymph node dissection was implemented if the lymph node metastasis was found. Artificial dura was used in eight cases when the dura was removed. Seven cases died. Two patients are currently undergoing follow-up. Other cases were without tumor detection from 1 to 7 years. When the comparative study between the above two groups, there is statistical significance about the influential factor: scar adherence to the skull (F = 5.602 P = .018). Scar adherence to the skull may be the most critical risk factor for cancer development for the scalp with chronic ulcer.

Treatment for Mycobacterium abscessus Infection Associated with Fat Grafting.

Background: Fat grafting is a standard method for soft augmentation. However, occasionally Mycobacterium abscessus infection can be seen secondary to fat grafting. The aim of this study was to report experience with and propose standard treatment. Patients and Methods: From 2006 to 2018, 12 women who had received fat grafting for facial soft augmentation in different Chinese private clinics were reviewed. Results: The patients presented with local swelling and skin ulceration. They patients received primary infusion of antibiotic agents; however, the results were poor. After being admitted to our hospital, cultures were taken and sent to the specialized examination center. Mycobacterium abscessus was diagnosed in all of the patients. According to drug sensitivity results, targeted antibiotic agent treatment was implemented for 12 months. Local proper conservative debridement was conducted as needed. When the patients were discharged from the hospital, they were advised to continual oral medication for six months. After three to nine years of follow-up, no recurrence was found. On the basis of this, a corresponding standard treatment was proposed. Conclusions: Mycobacterium abscessus infection after fat grafting should be diagnosed and treated accurately. Our experience and proposed treatment may be beneficial.

Measuring satisfaction with appearance: Validation of the FACE-Q scales for double-eyelid blepharoplasty with minor incision in young Asians- retrospective study of 200 cases.

BACKGROUND: Double eye-lid surgery is one of the most popular performed aesthetic procedures in young Asians. Reliable measurement of patient reported outcomes is crucial for facial aesthetics. The FACE-Q is a new patient-reported outcome tool (PRO) composed of numerous independently functioning scales and checklists designed to measure outcomes. Here we described FACE-Q scales for double eye-lid surgery with minor incision in young Asians. METHODS: 200 patients (400 eyes) aged from 21 to 30 years-old were recruited from 2012 to 2014. They underwent minor incision procedure for double-eyelid blepharoplasty, epicanthic fold correction, excessive orbit fat removal and blepharoptosis correction simultaneously. An incision of 1 cm long in the middle of upper eyelid and modified Park's Z-plasty for epicanthus correction were designed. Three stitches were carried out in levator aponeurosis-inferior dermis procedure. By the middle incision in the upper eyelid, blepharoptosis correction and excessive orbit fat removal can be executed. Those patients were asked to complete anonymously the FACE-Q by e-mail. FACE-Q scores were assessed for each domain (range, 0 to 100), with higher scores indicating greater satisfaction with appearance or superior quality of life. RESULTS: After a mean of 2 years' follow-up, postoperative complications included partial or complete loss of the double-eyelid fold in 8 and 0 cases, respectively, no hypertrophic scar formation, and asymmetric fold in four cases. One patient received re-operation on blepharoptosis correction. Except hematoma occurring in one female case, no obvious edema was observed. Patients demonstrated high levels of satisfaction with eye appearance overall (mean ± SD, 81.7 ± 18.3). Quality of Life Patients exhibited high levels of quality of life, including in social confidence (95.4 ± 12.6), psychological well-being (97.8 ± 10.3), and early life impact of the procedure (90.2 ± 13.4). Patients reported high satisfaction with the decision to undergo and the outcome of the procedure. CONCLUSIONS: Minimally invasive procedure is a reliable tool for correcting disfigurement in double-eyelid blepharoplasty. However, this method is not suitable for those cases whose upper eyelids are featured by relaxation. Excessive amount of skin must be removed. Patients who responded in this study were extremely satisfied with their decision to undergo double-eyelid surgery and the outcomes and quality of life following the procedure.

The clinical experience for treating post-burn depigmentation with tiny epidermal particles graft.

The critical problem of post-burn depigmentation is the lacking normal melanocytes. Auto-skin grafting and autologous non-cultured epidermal cell suspension have been used to improve the appearance. However, a large amount of skin graft is required of donor sites in the former method, while the latter method is thought to be complicated and costly. This study is designed to generalise the experience of tiny epidermal particles graft (TEPG) for treating post-burn depigmentation. From 2012 to 2013, 30 consecutive patients with depigmentation caused by burn injuries were divided into I and II group. I group: 15 cases (11 males and 4 females) were treated by the TEPG. II group: 15 patients (10 males and 5 females) were treated by suction blister epidermal skin graft (SBEG). Imagine-Pro Plus software was used to evaluate the size of repigmentation (RP) 12 months post-surgery. SPSS software 13.0 was used to evaluate the data. The optimum rate of RP was defined as more than 75% (RP > 75%) when excellent RP was defined as more than 90% (>90%). All patients were followed up for 12 months. The mean size of RP in two groups demonstrated that there were statistically significant differences in pigmentation between the two groups (P = 0·002), while there was no significant difference in the other factors (gender, site and age). No infection occurred in the recipient site. Pathological result showed that melanocytes existed at the basal layer of resurfacing skin. Optimum RP (RP > 75%) was seen in 12 patients in I group and 9 patients in II group. Excellent RP was achieved in 14 cases in I group and 10 patients in II group. Excellent RP can be obtained by the abovementioned two surgical techniques. In contrast to SBEG, TEPG is less traumatic, and definite effects can be guaranteed. It is a preferred treatment, especially for those patients who suffer from large depigmented lesions.

Clinical experience of surgically treating giant neurofibromatosis-1.

The surgical treatment for giant neurofibromatosis-1 (NF-1) requires comprehensive measures. Presently, there is no systematic description of surgical treatment. Because of its high level of risk, we want to share our clinical experience. From 2011 to 2014, patients (n = 8, 5 female and 3 male patients, aging from 31 to 45 years-old) were included in the study. The tumours were located on the trunk (n = 5) or face (n = 3). In addition to routine examination, blood storage was also prepared. Preoperative consultation from related departments was critical at first. Related artery embolisation was also carried out. In the operation, we checked thromboelastography, based on which reasonable blood component transfusion was implemented. Autologous blood transfusion was also ready. An instrument of copper needle or ring ligation was used to reduce haemorrhage before the surgery. Protruding or drooping portions of the tumours were excised. A pressurised bandage was applied when the surgery was completed. After the surgery, besides the routine monitoring of vital signs, re-haemorrhage should be detected in time. Then, we should decide whether blood transfusion or surgery was required again. Expanders were implanted in one female patient with facial injuries before removing the tumour. Then, expanded flaps were applied to repair the secondary wound. According to the above clinical route, after an average of 1-year follow-up, no patients died, and other unforeseen events did not occur. Wounds healed well in all patients. The tumor was excised as much as possible. No facial nerve paralysis occurred in the facial sites. Expanded flaps necrosis WAS not encountered. It is essential to design the educational clinical route for treating NF-1 when a giant protruding tumour is advised to be excised, which can minimise the risk of surgery and assure us of the maximum range of resection.

Retrospective study of primary reconstruction of facial traumatic events.

Facial traumatic events are commonly encountered in plastic and reconstructive surgery. Primary reconstruction is a reliable procedure with function and aesthetic considerations. We conduct a retrospective study of the experience of reconstructing facial traumatic defects in the first stage. One hundred and thirty-two cases (aged 18-65) with facial traumatic events were recruited in the study from 2008 to 2014. Facial traumatic events included injured soft tissue, maxillofacial fractures and facial nerve rupture, which were repaired primarily. After primary reconstruction, encouraging functional and aesthetic outcomes were attained. Ten cases were re-operated to reconstruct partial nasal defect. Four patients who had trouble with disabled occluding relations sought help from dentists. Inconspicuous scar and function restoration were presented. Facial wounds should be reconstructed in the first stage as far as possible. Then, satisfactory functional and aesthetic results can be achieved. However, combined injury should be carefully considered in those traumatic cases before we carry out the reconstructive surgery on the face.

Retrospective study of experience of craniofacial reconstruction.

Reconstruction is a basic task in craniofacial plastic surgery. Different methods must be used to meet the aspirations of surgeons and patients with different defects and deformities. We make a retrospective study of our experience of craniofacial reconstruction. In accordance with 10 years' clinical experience, direct suturing, skin graft transfer, nerve anastomosis, expanded pedicled or random flaps, facial local random flaps, reduction of mandibular fracture and correction of congenital craniofacial deformities were included in this case series. These types of treatment were applied to reconstruct facial defects or deformities according to different circumstances of patients. Directed by rational design and treatment, reconstructive surgery can be executed to treat different cases with different circumstances. A total of 891 different cases with different facial circumstances were treated with different methods: direct suturing (n = 93), skin graft transfer(n = 104), nerve anastomosis (n = 38), expanded pedicled or random flaps(n = 310), facial local random or pedicled flaps(n = 231), reduction of mandibular fracture(n = 112) and correction of congenital craniofacial deformities(n = 13). Reconstructive technique must be directed by reliable methods and special guidelines in Plastic Surgery. Three guidelines are summarised: reconstruction in the first stage and returning injured tissue to its origin site as far as possible for traumatic events; adjacent tissue must be prior to other distant tissue for reconstructive choice; and reconstruction at different stages after careful design.

Reconstruction of cica-contracture on the face and neck with skin flap and expanded skin flap pedicled by anterior branch of transverse cervical artery.

PURPOSE: A high-quality flap is necessary for repairing faciocervical scar contractures. The supraclavicular region and chest wall are the preferred choices for reconstruction. The supraclavicular island flap (SIF) pedicled by the transverse cervical artery (TCA) has been reported. Compared to the traditional SIF flap, another type of flap pedicled by the anterior perforator of transverse cervical artery (ap-TCA) is more convenient for transfer to the faciocervical area. In this article, we use this type of perforator flap and expanded perforator flap to repair the faciocervical contracture. MATERIAL AND METHODS: In this study, 10 cases (deformity caused by burn or trauma to the face and neck sites) with an average age of 32 years-old, were treated by ap-TCA flap and this type of expanded flap. In between, the flap was pre-expanded for approximately 3 months prior to transfer in 6 patients. Another 4 cases did not want the expander because of the long duration required for saline filling and potential complications of the expander. Bilateral prefabricated flaps were designed in two female cases. RESULTS: All 12 flaps in 10 patients were transferred tension-free to the defects and no flap was lost. The size of the flap ranged from 12 cm × 8 cm to 15 cm × 20 cm. All 12 flaps survived completely. The donor sites were closed directly in the above 6 patients where an expander had been used and reconstructed by split skin graft in 4 patients where no expander had been employed. Through a mean time of 6 months' follow-up, only one female patient was disappointed with the cicatrix that presented on the upper polar skin of both breasts, the other 9 patients were satisfied with both recipient function and appearance. The color and the texture matched well with the recipient area. CONCLUSION: The ap-TCA flap and expanded ap-TCA flap can be considered reliable options for faciocervical deformities as it can be easily elevated and it matches well with faciocervical area in color. With regards to the expanded flap, we cannot only reconstruct the face and neck region, but also suture the donor site directly.

Pedicled fasciocutaneous flaps for correcting scar contracture in pediatric patients-a retrospective study of 22 cases.

BACKGROUND: Pediatric scar contractures in rapidly-growing regions require timely correction. Compared to flaps, skin grafts are characterized by scarring and retraction. More complex reconstructions are especially challenging in pediatric cases. Pedicled fasciocutaneous flaps are simple, durable, and able grow with the patient. METHODS: A series of 22 pediatric burn scar cases, with an average age of 6years, underwent treatment with pedicled fasciocutaneous flaps. They comprised 17 patients with scars involving the chest and axilla, and 5 patients with scars involving the groin and perineum. RESULTS: Patient follow-up ranged from 3months to 2years, and included every patient. In total, 25 flaps were performed, comprising 4 lateral thoracic flaps, 5 superficial inferior epigastric artery flaps, and 16 scapular/expanded scapular flaps. Adjunctive skin grafts were used in 3 cases; the remaining 19 cases' donor sites were closed primarily. No flap loss or necrosis was observed. CONCLUSIONS: Pedicled fasciocutaneous flaps are robust treatment options for burn scar contractures. Accompanied by tissue expander, it can be raised to repair larger area of contracture.

Surgical treatment of severe or moderate axillary burn scar contracture with transverse island scapular flap and expanded transverse island scapular flap in adult and pediatric patients--A clinical experience of 15 cases.

BACKGROUND: Axillary burn scar contracture is common and troublesome. With the aim of restoring the function of the upper extremities, a proper local flap with minor damage and preclusion from recurrence should be developed to guarantee satisfactory results. A minor webbed scar contracture was rectified by Z-plasty. However, severe or moderate contracture must be constructed by a local flap. An island scapular flap has been used in pediatric patients for repairing axillary contracture. However, no detailed description of the use of a transverse island scapular flap (TISF) was reported to correct the deformity. Moreover, an expanded transverse island scapular flap (ETISF) used for increasing the volume of skin for severe axillary contracture in adults and developing children was also not presented. METHODS: From 2006 to 2013, TISFs were harvested for 12 pediatric patients (5-12 years of age) with 15 sides of severe or moderate axillary burn scar contractures. Four ETISFs were designed for two adult patients (38 and 32 years of age). The flap size was between 10 cm×5 cm and 20 cm×10 cm. In one pediatric patient, a cicatrix was observed on the surface of the flap's donor site. Handheld Doppler was applied to detect the pedicle. RESULTS: The patients were required to lift their upper arms regularly each day after the operation. All 19 flaps survived completely. Axillary burn scar contractures were corrected successfully in 11 patients with no expander implantation. The lifting angle was enhanced considerably with 1-3 years of follow-up in the 11 patients. Only one pediatric patient with cicatrix on the donor site displayed tight skin on the back and a little restraint on the shoulder. The patient's parents were told to intensify the chin-up movement on the horizontal bar. She was in the process of a 3-month follow-up. The lifting angle was also improved significantly in the latter three cases of expander implantation although they were followed up for a short duration of 3 months. Due to poor flap design, the donor site of one adult patient was not closed directly with the help of skin grafting on the left side of her back. CONCLUSIONS: Considering the flap's negligible level of later contracture and minimal trauma, local TISF based on the transverse branch of the circumflex scapular artery is a good choice for reconstruction of axillary burn scar contractures. If the TISF is not able to meet the demand, the expander implanted in advance can be more beneficial.

Treatment and Rehabilitation of Knee Joints Straight Stiffness After Burns.

The knee release surgery and postoperative rehabilitation of patients after burns and knee straight stiffness were investigated. Eleven patients were treated for 16 side burns and knee stiffness who consisted of nine males and two females, aged 19 to 54 years (mean = 33.2). The duration of the patients' knee stiffness ranged from 8 to 26 months, with an average of 12.6 months. Their preoperative flexion ranged from 5° to 50°, with an average of 26.2°. Their preoperative Hospital for Special Surgery (HSS) knee scores ranged from 46 to 72 points, with an average of 55.8 points. All stiff knees were treated with release surgery, along with total release of intra-articular adhesion and excision of vastus intermedius. After the arthrolysis of the stiff knee joint, the tight skin was completely loose in the adhesions. The soft tissue contracture was not grafted, but the shade fascia was freed to increase skin ductility. All knee joints were released to more than 90° of flexion in the operation, and reversed fascia flaps were used to suture the loss of the deep fascia at the position of flexion of 90°. After the operation, the knee joint was fixed in flexion for 72 h while being actively cared for by early rehabilitation. Subsequently, the patient's skin coverage, joint motion, and joint function recovery were observed. Based on the follow-up of the patients for the following 16 to 36 months (mean = 25.7), the knee flexion of the patients ranged from 110° to 135°, with an average of 122.2° and 96° increase (P < 0.01). Furthermore, the patients had better skin ductility to meet the increase in joint flexion. HSS knee function scores at the end of follow-up ranged from 93 to 100 points, with an average of 97.5 points and an increase of 41.7 points (P < 0.01). The joint function improved significantly. The arthrolysis of straight stiff knee joints after burns can ease muscle contracture and free the shade fascia, thus avoiding the need to undergo skin grafting. Short-term fixation of the joints after surgery and active flexion rehabilitation may also be the key to improve skin ductility and joint function of the patients.

Influence of hyaluronic acid on wound healing using composite porcine acellular dermal matrix grafts and autologous skin in rabbits.

This study aims to explore the influence of hyaluronic acid (HA) on wound healing during xenogeneic porcine acellular dermal matrix (PADM) composite skin grafting. The results will facilitate the development of methods for improving graft contracture and poor elasticity of composite transplantation. Exogenous HA was added to composite PADM grafts and to thin autologous skin grafts during rabbit full-thickness skin wound repair. The influence of HA on wound healing was evaluated according to its contracture rate and its expression of collagen types I and III. The possible mechanism was then explored based on HA metabolism and vascularisation in the skin graft. The results show that exogenous HA relieves graft contracture on rabbit wound surfaces, increases collagen I and III expression and decreases the ratio between collagen types. HA stimulates the generation of more CD44 receptors to strengthen its enzymolysis. The resulting metabolites promote the vascularisation of the wound surface, which are conducive for mitigating graft contracture, and further improve the composite grafting effect.

[Reparation and restitution of head tissue deletion with fascia lata and local flap].

OBJECTIVE: To explore the effect of reparation and restitution of head tissue deletion with autologous fascia lata and local flap. METHOD: The clinical data of 8 cases with scalp squamous celled carcinoma from 2003 to 2010 were summarized retrospectively. All patients carcinoma were removed almost, cerebral dura mater deletion and skin deletion from 5 cm to 15 cm, repaired cerebral dura mater with autologou fascia lata; and restitution scalp with local flap, the area of local flap were planted with free skin graft. RESULT: The outcomes of the treatment with fascia lata were very well, and the local flap of all cases were survival the free skin graft were survival from 85% to 100%. There was no leakage of cerebrospinal fluid or intracranial infection during follow-up. CONCLUSION: The method of repairation and reconstruction of head tissue deletion with fascia lata and local flap is effective, the out comes are satisfying.

[Mandibular-driven simultaneous maxillo-mandibular distraction for hemifacial microsomia with rapid prototyping technology].

OBJECTIVE: To explore the clinical application of mandibular-driven simultaneous maxillo-mandihular distraction to correct hemifacial microsomia with rapid prototyping technology. METHODS: The patient' s skull resin model was manufactured with rapid prototyping technology. The osteotomy was designed on skull resin model. According to the preoperative design, the patients underwent Le Fort I osteotomy and mandibular ramus osteotomy. The internal mandible distractor was embedded onto the osteotomy position. The occlusal titanium pin was implanted. Distraction were carried out by mandibular-driven simultaneous maxillo-mandihular distraction 5 days after operation. RESULTS: The distraction in five patients was complete as designed. No infection and dysosteogenesis happened. The longest distance of distraction was 28 mm, and the shortest distance was 16 mm. The facial asymmetry deformity was significantly improved at the end of distraction. The ocelusal plane of patients obviously improved. CONCLUSIONS: Rapid prototyping technology is helpful to design precisely osteotomy before operation. Mandibular-driven simultaneous maxillo-mandibular distraction can correct hemifacial microsomia. It is worth to clinical application.

[Effects of hyaluronic acid on biomechanic performance of porcine acellular dermal matrix plus thin skin autograft after transplantation].

OBJECTIVE: To explore the effects of hyaluronic acid (HA) on biomechanical properties for porcine acellular dermal matrix (PADM) plus thin skin autograft after transplantation. METHODS: The dorsa of 10 Japanese white rabbits were symmetrically divided into four areas of A-D by random grouping. Full-thickness skin defects were created in Groups A-C while Group D was blank with normal skin. Operations were performed in Group A: implant with HA + PADM + thin skin autografts, Group B: implant with PADM + thin skin autografts and Group C: skin autografts group. Histological examination of specimen was performed at Day 56 postoperatively. And the biomechanical properties such as relaxation and stress-strain properties of grafts were recorded. RESULTS: The structure of PADM was found to be basically intact by hematoxylin and eosin E dyeing in Groups A and B. In Group A, dense fiber structure could be observed. Lots of regularly arranged collagenous fibers and new blood capillaries were grown into the dermal matrix with sparsely distributed inflammatory cells. In Group B, acellular dermal matrix became clustered with a small amount of invaded fibroblasts. And there was a high expression of inflammatory cells. The biomechanic performances of transplanted skin were: Group A's curve was mostly close to that of Group D's, Group B's curve was the most further from that of Group D's (P = 0.001) and Group C's curve stayed between Groups A and B. Under the same strain, the stress of Groups A-D was (87 ± 8), (115 ± 9), (63 ± 7) and (81 ± 4) kPa respectively. No significant difference of stress existed between these two groups (P = 0.838). There was significant difference of stress between Groups B/C and D (P = 0.001 and P = 0.009). CONCLUSION: Topical hyaluronic acid may be used to enhance the biomechanics performances of transplanted skin.