Reconstruction of Large Area of Deep Wound in the Foot and Ankle with Chimeric Anterolateral Thigh Perforator Flap.

OBJECTIVE: To evaluate the clinical application and surgical efficacy of the chimeric perforator flap pedicled with the descending branch of the lateral circumflex femoral artery and the lateral thigh muscle flap for the reconstruction of the large area of deep wound in foot and ankle. METHODS: Clinical data of 32 cases who underwent chimeric anterolateral thigh perforator flap to repair the large area of deep wound of the foot and ankle from January 2015 to December 2018 were retrospectively analyzed. The sizes of the defects ranged from 18 cm × 10 cm to 35 cm × 20 cm, with exposed tendon and bone and/or partial defects and necrosis, contaminations, accompanied by different degrees of infection. Following the radical debridement and VSD, chimeric anterolateral thigh perforator flap was employed to repair the deep wounds according to the position, site and deep-tissue injury of the soft-tissue defects. The skin flap and muscle flap were fanned out on the wound, and single- or two-staged split-thickness skin grafting was performed on the muscle flap. The operation time and blood loss were recorded. The survival and healing conditions of the operational site with chimeric anterolateral thigh perforator flap were evaluated post-operationally. Complications at both recipient site and donor site were carefully recorded. RESULTS: The mean time of the operation was 325.5 min and average blood loss was 424.8 mL. Among the 32 cases, two cases developed vascular crisis, which were alleviated with intensive investigation and treatment; Four cases suffered from partial necrosis of the flap or skin graft on the muscle flap or on the residual local wound, which were improved after treatment of further dressing change and skin grafting. Another four cases experienced post-traumatic osteomyelitis accompanied by bone defect were treated with simple bone grafting or Mesquelet bone grafting at 6-8 months after wound healing. Postoperatively, the wounds were properly healed, and the infection was effectively controlled without sinus tract forming. Overall, all 32 cases received satisfactory efficacy, without influencing subsequent functional reconstruction, and observed infection during the 12-36 months post-operational follow-up. CONCLUSION: The chimeric perforator flap pedicled with the descending branch of the lateral circumflex femoral artery and the lateral thigh muscle flap provides an effective and relative safe procedure for the repair of a large area of deep wound in the foot and ankle, particularly with irregular defect or deep dead space.

Free flap transplantation combined with Ilizarov bone transport for the treatment of severe composite tibial and soft tissue defects.

OBJECTIVE: To evaluate the clinical efficacy of free flap transplantation combined with Ilizarov bone transport in the treatment of severe composite tibial and soft tissue defects. METHODS: We retrospectively analyzed the clinical data of 40 patients with severe composite tibial and soft tissue defects who underwent free flap transplantation combined with Ilizarov bone transport. The clinical efficacy was evaluated according to the following criteria: success rate of wound repair by free flap transplantation, incidence or recurrence rate of deep infection, healing rate of bone defects and external fixation index, incidence of complications, and functional score of affected extremities. RESULTS: All infections were generally well controlled by radical debridement and negative-pressure therapy, and all 40 patients' wounds healed after repair and reconstruction of the tibia and soft tissues. Postoperative complications were alleviated by active treatment. The mean external fixation time was 12.83 ± 2.85 months, and the external fixation index was 1.55 m/cm. According to the Association for the Study and Application of Methods of Ilizarov (ASAMI) score, an excellent or good functional outcome was attained in 85% of patients. CONCLUSION: Free flap transplantation combined with Ilizarov bone transport is an effective treatment for severe composite tibial and soft tissue defects.

A neglected problem in the utilization of free anterolateral thigh flap toward reconstructing complicated wounds of extremities: the obliteration of deep dead space.

BACKGROUND: Deep dead space may be thought as an independent risk factor of the poor infection control after flap reconstruction in complex limb wounds. But it can be easily neglected. The conventional skin flap and musculocutaneous flap are difficult to obliterate the deep dead space in irregular shape effectively. It was investigated that the clinical application of chimeric anterolateral thigh perforator flap in the treatment of complex wounds complicated with deep dead space of the extremities in the paper. METHODS: Fifty-six cases complicated with deep dead space wounds were registered in group. Following thorough debridement and treatment with VSD, the granulation tissues grew with well-controlled infection. And then the chimeric anterolateral thigh perforator flap was used to obliterate the deep dead space and repair the wounds. The postoperative flap survival and infection conditions were evaluated. RESULTS: Overall, the infection was effectively controlled, without persistent exudation or sinus tract formation after wound healing. While 5 cases lost to follow-up, the remaining 51 cases were followed up until 15 months on average. Generally, the affected extremities recovered satisfactorily with normal appearances and texture of the flaps, along with normal functions. Importantly, no recurrence of infection was observed. CONCLUSION: During the grafting of chimeric perforator flap pedicled with lateral thigh muscle flap, the muscle flap is recommended to obliterate the deep dead space while the skin flap is being used to cover the wound. The combination of these two technologies performed well in the repair and reconstruction of the complex wounds of the extremities, possessing potential for broader clinical application.

Treatment options for infected bone defects in the lower extremities: free vascularized fibular graft or Ilizarov bone transport?

OBJECTIVE: The objective was to explore the relative indications of free vascularized fibular graft (FVFG) and Ilizarov bone transport (IBT) in the treatment of infected bone defects of lower extremities via comparative analysis on the clinical characteristics and efficacies. METHODS: The clinical data of 66 cases with post-traumatic infected bone defects of the lower extremities who underwent FVFG (n = 23) or IBT (n = 43) from July 2014 to June 2018 were retrieved and retrospectively analyzed. Clinical characteristics, operation time, and intraoperative blood loss were statistically compared between two groups. Specifically, the clinical efficacies of two methods were statistically evaluated according to the external fixation time/index, recurrence rate of deep infection, incidence of complications, the times of reoperation, and final functional score of the affected extremities. RESULTS: Gender, age, cause of injury, Gustilo grade of initial injury, proportion of complicated injuries in other parts of the affected extremities, and numbers of femoral/tibial defect cases did not differ significantly between treatment groups, while infection site distribution after debridement (shaft/metaphysis) differed moderately, with metaphysis infection little more frequent in the FVFG group (P = 0.068). Femoral/tibial defect length was longer in the FVFG group (9.96 ± 2.27 vs. 8.74 ± 2.52 cm, P = 0.014). More patients in the FVFG group presented with moderate or complex wounds with soft-tissue defects. FVFG treatment required a longer surgical time (6.60 ± 1.34 vs. 3.12 ± 0.99 h) and resulted in greater intraoperative blood loss (873.91 ± 183.94 vs. 386.08 ± 131.98 ml; both P < 0.05) than the IBT group, while average follow-up time, recurrence rate of postoperative osteomyelitis, degree of bony union, and final functional scores did not differ between treatment groups. However, FVFG required a shorter external fixation time (7.04 ± 1.72 vs. 13.16 ± 2.92 months), yielded a lower external fixation index (0.73 ± 0.28 vs. 1.55 ± 0.28), and resulted in a lower incidence of postoperative complications (0.87 ± 0.76 vs. 2.21±1.78, times/case, P < 0.05). The times of reoperation in the two groups did not differ (0.78 ± 0.60 vs. 0.98 ± 0.99 times/case, P = 0.615). CONCLUSION: Both FVFG and IBT are effective methods for repairing and reconstructing infected bone defects of the lower extremities, with unique advantages and limitations. Generally, FVFG is recommended for patients with soft tissue defects, bone defects adjacent to joints, large bone defects (particularly monocortical defects), and those who can tolerate microsurgery.

[Application of medical biomaterials in prevention and treatment of tendon adhesion].

OBJECTIVE: To review the research progress of medicine biomaterials in prevention and treatment of adhesion after tendon injury, and to provide reference for clinical treatment. METHODS: The literature on the application of medical biomaterials in the prevention and treatment of tendon adhesions in recent years was reviewed, and the biological process, treatment methods, and current status of tendon adhesions were summarized. RESULTS: Tendon adhesion as part of the healing process of the tendon is the biological response of the tendon to the injury and is also a common complication of joint dysfunction. Application of medical biomaterials can achieve better biological function of postoperative tendon by reducing the adhesion of peritendon tissues as far as possible without adversely affecting the tendon healing process. CONCLUSION: The use of medical biomaterials is conducive to reduce the adhesion of tendon after operation, and the appropriate anti-adhesion material should be selected according to the patients' condition and surgical needs.

Bone Transport for Treatment of Traumatic Composite Tibial Bone and Soft Tissue Defects: Any Specific Needs besides the Ilizarov Technique?

OBJECTIVE: To evaluate the surgical efficacy of bone transport (Ilizarov technique) plus "shortening-lengthening," "flap surgery," and "open bone transport" as individualized treatments for traumatic composite tibial bone and soft tissue defects. METHODS: We retrospectively analyzed sixty-eight cases (mean age: 35.69 years, (range, 16-65)) treated from July 2014 to June 2017, including 29 middle, 18 distal, and 21 proximal tibial bone defects (4-18 cm, mean: 7.97 cm) with soft tissue defects (2.5 cm × 4.0 cm to 30.0 cm × 35.0 cm after debridement). We adopted the bone transport external fixator to fix the fracture after debriding the defect parts. In the meantime, we adopted the "shortening-lengthening technique," "flap surgery," and "open bone transport" as individualized treatment based on the location, range, and severity of the composite tibial bone and soft tissue defects. Postoperative follow-up was carried out. Surgical efficacy was assessed based on (1) wound healing; (2) bone defect healing rate; (3) external fixation time and index; (4) incidence/recurrence of deep infection; (5) postoperative complications; and (6) Association for the Study and Application of the Methods of Ilizarov (ASAMI) score. RESULTS: The mean duration from injury to reconstruction was 22 days (4-80 d), and the mean postoperative follow-up period was 30.8 months (18-54 m). After the repair and reconstruction, 2 open bone transport patients required infected bone removal first before continuing the bone transport treatment. No deep infection (osteomyelitis) occurred or recurred in the remaining patients, and no secondary debridement was required. Some patients had complications after surgery. All the postoperative complications, including flap venous crisis, nail channel reaction, bone nonunion, mechanical axis deviation, and refracture, were improved or alleviated. External fixation time was 12.5 ± 3.41 months, and the index was 1.63 ± 0.44. According to the ASAMI score, 76.47% of the outcomes were good/excellent. CONCLUSION: The Ilizarov technique yields satisfactory efficacy for composite tibial bone and soft tissue defects when combined with "shortening-lengthening technique," "flap surgery," and "open bone transport" with appropriate individualized treatment strategies.

Free flap transplantation combined with skin grafting and vacuum sealing drainage for repair of circumferential or sub-circumferential soft-tissue wounds of the lower leg.

BACKGROUND: This study is aimed at evaluating the operation techniques and clinical significance of free flap transplantation combined with skin grafting and vacuum sealing drainage (VSD) in repairing severe traumatic extensive circumferential or semi-circumferential soft-tissue defects of the lower leg. MATERIAL AND METHODS: Thirty patients with severe lower leg injuries were treated by free flap transplantation combined with skin grafting and VSD from January 2008 to June 2011. The size of the wounds ranged from 23×8 cm to 44×28 cm and all affected more 70% of the low leg circumferential area. Wounds were complicated by exposure, necrosis, or infection of deep tissues. The wounds were first debrided and covered by VSD. When the condition of the wound had improved (5 to 7 days later), free flaps were harvested to reconstruct damaged tissue and skin grafts and VSD was used to cover granulation tissues around the transplanted flap. RESULTS: Granulation tissues developed and the area requiring flap cover decreased in all 30 patients after debridement and VSD. In 28 of 30 cases, the transplanted flaps grew well without complication. Peripheral necrosis was observed in only 2 cases, which required a second debridement and skin graft. Ten wound areas covered by grafts were left with scattered peripheral wounds, which healed with the help of 1 more skin graft or dressing change. Morphological appearance and functional recovery were satisfactory in all 30 cases. CONCLUSIONS: Initial debridement and the temporary VSD cover followed after several days by free flap transplantation combined with skin grafting and VSD protection is a reliable treatment regimen for traumatic large circumferential or sub-circumferential soft tissue wounds of the lower leg with deep tissue exposure.

Reconstruction of shoulder abduction by multiple nerve fascicle transfer through posterior approach.

PURPOSE: To evaluate the feasibility and clinical efficacy of multiple nerve fascicle transfer through posterior approach for reconstruction of shoulder abduction in patients with C5 or upper brachial plexus injury. METHODS: 11 patients (aged between 17 and 56 years) with dysfunction of shoulder abduction post C5 or upper brachial plexus injury were recruited in this study. Among them, four out of 11 patients also had dysfunction of elbow flexion simultaneously. The duration from injury to the surgery ranged from 4 to 12 months, with an average of 6.7 months. The affected shoulder joints showed abduction, extension and elevation dysfunction, but the muscle strength of shoulder shrugging and elbow extension was graded to M4 or higher. Accessory nerve was transferred to the suprascapular nerve and triceps muscle was branched to the axillary nerve through posterior approach. Ulnar fascicle was transferred to the motor branches of biceps for the 4 patients involved with elbow flexion dysfunction. RESULTS: Ten out of 11 cases were followed-up for 15-36 months. Neo-potential of deltoid and supraspinatus/infraspinatus was documented at 4-5 months post surgery. Shoulder abduction (and elbow flexion) was reanimated at 4-8 months post surgery. Significant improvement was observed at 15-36 months post surgery, shoulder abduction regained to 40-160° (mean: 92.5°), muscle strength of supraspinatus/infraspinatus and deltoid were graded to M3-M5 (mean: 4.0 and 4.1); 3 cases muscle strength of elbow flexion was graded from M4 to M5- (mean: 4.4) with 1 case loss. Shoulder shrugging of trapezius was graded to M5 in 5 cases, M5- in 2 cases, M4 in 2 cases and M3 in 1 case (mean: 4.5). All cases showed normal elbow extension and muscle strength of triceps (M5). CONCLUSION: It is feasible to carry out multiple nerve fascicle transfers for early reconstruction of shoulder abduction by posterior approach. Patients who received this procedure achieved good functional recovery and their donor site morbidity/injury was minimal.

[Treatment of large circular soft tissue defect in lower extremities with a combination of bridge flaps and free skin graft covered by vacuum sealing drainage].

OBJECTIVE: To explore the surgical technique and clinical value of treatment for posttraumatic large circular soft tissue defect in the lower extremities using a combination of posterior tibial vascular bridge flap in the unaffected leg and skin graft covered by vacuum sealing drainage (VSD). METHODS: From January 2008 to June 2010, 11 cases with posttraumatic large circular soft tissue defects with deep tissue exposed or partial necrosis in the lower extremities were treated by bridge flaps and combined with free skin graft covered by VSD. There are 7 males and 4 females, with an average age of 32.5 years (range from 15 to 52 years). The size of wound varied from 24 cm × 13 cm to 45 cm × 24 cm. After the wound were completely debrided, the external fixation or internal fixation was conducted for the patients with unstable fracture. Then VSD were used to covered the wound for 1-2 times with a period of 5 to 7 days according to the wound condition. After granulation tissue grew, bridge flap transplantation was performed to repair tissue defect and cover the exposed bone, which combined with skin graft covered by VSD was used to cover the residual wound. Survival rate and quality healing of the flaps were followed up postoperatively. RESULTS: The granulation growth of 11 cases with large circular soft tissue defect in the lower extremities associated tissue exposure was good after the application of VSD. All the cases were covered by free flap transplantation and skin grafting except for 6 cases due to large defect. The wound was covered by skin re-grafting in 4 cases and frequently dressing change in 2 cases. All the flaps were successful with good infection control and no sinus. The average period of follow-up was 10.6 months (5 - 24 months). All the patients were satisfied with the good outline and good function of the affected limb. CONCLUSION: Patients with posttraumatic large circular soft tissue defect in the lower extremities can be effectively treated with a combination of bridge flaps and free skin graft covered by VSD, which can shorten the course of treatment, and restore the function of affected extremities as much as possible.

Removal of an intra-abdominal Kirschner wire under digital subtraction angiography: a pediatric case report.

Intra-abdominal migration of Kirschner wire is unusual in children. We present a case of intra-abdominal migration of Kirschner wire used for stabilization of the hip joint during pelvic osteotomy, and its successful removal under digital subtraction angiography.

Sequential therapy of vacuum sealing drainage and free-flap transplantation for children with extensive soft-tissue defects below the knee in the extremities.

PURPOSE: The aim of the study is to evaluate the surgical technique and clinical significance of the sequential therapy of vacuum sealing drainage (VSD) and free-flap transplantation for children with extensive soft-tissue defects below the knee in the extremities. METHODS: Twenty-two children (aged from 3 to 10 years) received sequential therapy of VSD and free-flap transplantation. All cases suffered from extensive area soft-tissue defects and exposure or partial defects of bones, tendons and other deep tissues. The wound sizes varied from 10 cm × 6 cm to 30 cm × 22 cm. Amongst 22 cases, 12 cases had fresh wounds and the remaining 10 children had necrotising infection. After complete debridement, the wounds were covered by VSD. External fixation or Kirschner-wire fixation should be performed for the cases complicated by unsteady fractures. After the removal of negative pressure VSD devices, free-flap transplantations were performed in 8 cases after debridement, and 14 cases received combined therapy of free-flap transplantation and skin grafting depending upon the severity of soft-tissue and deep-tissue defects. The flap survival and wound healing were followed up postoperatively. RESULTS: After VSD treatment, the infection of deep-tissue exposure was effectively prevented, and granulation tissues surrounding the exposed areas of tendons and bones grew well. All patients who received free-flap transplantation at the second stage survived without the occurrence of vascular crisis, infection or sinus formation. During follow-up ranging from 6 to 24 months, all the patients were satisfied with the morphological appearance and functional recovery of the affected limbs. CONCLUSION: Sequential therapy of VSD and free-flap transplantation can serve as a reliable option for children with extensive soft-tissue defects below the knee in the extremities and exposed deep tissues, after complete debridement, which significantly shortens remedy period, enhances success rate for surgery and achieves maximal restoration of limb function.

Effects of mechanical strain on oxygen free radical system in bone marrow mesenchymal stem cells from children.

BACKGROUND: Physiological loading is widely believed to be beneficial in maintaining skeletal integrity by stimulating new bone formation through increases in osteoblastic activity and concomitant decreases in osteoclastic activity. However, excessive or nonphysiological loading is associated with bone injuries, including stress fractures and osteoporotic fractures, thereby leading to a decreased functional capacity of bone. It is known that the excessive generation of reactive oxygen species (ROS) is a significant factor underlying tissue injury observed in many disease states. The aim of this study was to study the effects of mechanical strain on oxygen free radical system [ROS, superoxide dismutase (SOD) and malondialdehyde (MDA)] in bone marrow mesenchymal stem cells (MSCs) from children. METHODS: To determine whether extreme levels of mechanical strain enhance ROS synthesis, we loaded cyclic tensile stretch of varying magnitude on MSCs. After MSCs were stimulated by mechanical strain, ROS labelled with 2,7-dichlorodihydrofluorescein (DCFH) fluorescent probe in cells were detected by flow cytometry (FCM) whilst SOD activity and MDA level were detected by xanthine oxidase method and thiobarbituric acid method, respectively. RESULTS: Extreme levels (>12%) of mechanical strain applied to children's MSCs enhanced ROS synthesis, decreased the activity of SOD and increased the level of MDA, in a time- and magnitude-dependent fashion. CONCLUSIONS: These data suggest that excessive magnitude of cyclic tensile strain (>12%) could induce oxygen free radical disequilibrium, resulting in cytotoxicity. The findings may have clinical implications for orthopaedic practice.

[Three-dimensional reconstruction technique in gastrocnemius flap surgery: initial clinical application].

OBJECTIVE: To discuss the experience with three-dimensional reconstruction technique in initial clinical application in gastrocnemius muscle flap surgery. METHOD: From 2007 to 2008, 7 patients received gastrocnemius muscle flap surgeries to repair the wounds. Preoperative CT angiography or magnetic resonance imaging (MRI) was performed after injection of the contrast media for individualized three-dimensional gastrocnemius muscle flap reconstruction using Amira4.1 software. According to the size of the defect in the wound, individualized three-dimensional gastrocnemius muscle flap was designed and harvested from the posterior leg. RESULTS: Individualized three-dimensional reconstruction of the gastrocnemius flap was performed in 7 cases, and the reconstructed flaps clearly displayed the blood vessels, skin and the adjacent three-dimensional structures. In 6 cases the main perforating branched and trunk of the blood vessels in the designed flap were consistent with the surgical findings; in 1 case, the perforating branches failed to be clearly displayed in the designed flap, and surgical examination identified perforating branches with an average diameter of 0.5 mm (minimally 0.3 mm). The flaps survived in all the 7 cases. CONCLUSIONS: Three-dimensional reconstruction of the gastrocnemius flap based on the lower limb CT angiography or MRI allows three-dimensional observation of the anatomy of the flap and accurate marking of the extent of the flap to be harvested, therefore avoiding intraoperative injuries to the blood vessels to better survival of the flaps.

[Research progress on three-dimensional reconstruction and visualization of peripheral nerve].

OBJECTIVE: To review the research progress on the three-dimensional (3D) reconstruction and visualization of peripheral nerve. METHODS: Literature about the research on the 3D reconstruction and visualization of peripheral nerve both at home and abroad were extensively reviewed and thoroughly analyzed. RESULTS: The application of 3D reconstruction and visualization technology was capable of not only reappearing the 3D outer contour and spatial adjacent relationship of peripheral nerve veritable but also displaying, rotating, zooming, dividing and real-time measuring their 3D internal structure and the delicate pathways in any direction either separately or totally. Preliminary achievements were achieved in terms of brachial plexus, lumbosacral plexus, the functional cluster of nerve trunk, intramuscular nerve distribution pattern, peripheral nerve regeneration and the 3D reconstruction and visualization research of complex tissue including peripheral nerve. However, the research on the visualization of peripheral nerve was still in the initial stage since such problems as recognition, segmentation, registration and fusion of the peripheral nerve information were not resolved yet. CONCLUSION: Researching 3D reconstruction and visualization of the peripheral nerve is of great value for updating the diagnosis and treatment principle of peripheral nerve injury, improving its diagnosis and treatment method and launching a new way for the studying and teaching, which may be a new growing point for the peripheral nerve surgery.

Replantation of articular composite tissue masses severed from extremities.

SUMMARY: The techniques and outcomes of in situ replantation are discussed for managing 5 cases of articular composite tissue masses severed from an extremity (digit). All 5 cases treated with in situ replantation survived. Rehabilitation was performed after surgery. Follow-ups of 2-5 years showed good appearance, satisfactory functional and sensory recovery. In situ replantation is indicated for an articular composite tissue masses severed from an extremity (digit), if its structure is complete and a blood supply vessel in the mass is available for anastomosis. Replantation can achieve better outcomes than transfer or grafting of adjacent skin or osteocutaneous flaps, or transplantation of a metatarsophalangeal or interphalangeal joint.

Reconstruction of phalangeal articulations of the hand with vascularised phalangeal articulations of foot.

SUMMARY: Since arthroplasty, prosthetic replacement and non-vascularised articulation autografting do not normally produce very satisfactory results for ankylosis of metacarpophalangeal and interphalangeal joints, the authors performed reconstruction of phalangeal articulations of the hand using vascularised phalangeal articulations of the foot in 11 patients with ankylosis of the metacarpophalangeal and interphalangeal joints of hand due by trauma. Procedures included reconstruction of 9 hand metacarpophalangeal joints with vascularised grafting of pedal metatarsophalangeal joints in six patients, reconstruction of the hand metacarpophalangeal joints with grafting of vascularised proximal interphalangeal joints of foot in two patients and reconstruction of the hand proximal interphalangeal joints with grafting of vascularised proximal interphalangeal joints of foot in three patients. Early functional exercise was encouraged in all cases post-operatively. Follow-up ranged from 3 to 10 years and revealed that 9 cases had normal appearance and length of recipient area, 1 had slightly clumsy dorsal skin in the hand and 1 had slight dorsal angulation of a metacarpal bone. Recovery of joint range of motion was satisfactory. Radiographic, gross and sensation examinations also showed good operative outcomes. The authors believe that vascularised pedal metatarsophalangeal joints, with a rich blood supply, can be grafted to effectively reconstruct the finger joints with good function. A low rate of degeneration results because pedal and hand metatarsophalangeal joints are similar in anatomy and physiological function.

[Green fluorescent protein as a tracer of bone marrow stromal cells in bone tissue engineering in rhesus].

OBJECTIVE: To observe the role of green fluorescent protein (GFP) in tracing rhesus bone marrow stromal cells (rBMSCs) during tissue-engineered bone formation in vivo. METHODS: Ad5.CMV-GFP was amplified by infecting QBI-293A cells, and the bone marrow was harvested from the ilium of adult male rhesus to obtain rBMSCs, which were cultured and passaged in vitro. GFP was transfected into the third-passage rBMSCs via adenovirus vector and the labeled cells were inoculated into absorbable HA scaffold and cultured for 3 days, with untransfected rBMSCs as control, before the cell-matrix compounds were implanted into the latissimus dorsi muscles of rhesus. Samples were harvested at 6 week and embedded in paraform, and ground sections of the bone tissue were prepared to observe green fluorescence under laser scanning confocal microscope. Propidium iodide staining of the sections was also performed for observation. RESULTS: The rBMSCs grew well after GFP transfection, and green fluorescence could be seen 24 h after the transfection and became stronger till 48 h, with a positive transfection rate beyond 80%. Six weeks after cell implantation, the rBMSCs labeled by GFP-emitted green fluorescence were detected in the bone tissue under laser scanning confocal microscope. CONCLUSION: GFP can effectively trace BMSCs during bone tissue engineering, and the transplanted BMSCs constitute the main source of bone-forming cells in bone tissue engineering.

[Influence of high molecular weight polyethylene on viability of osteoblasts and new bone formation].

To investigate the influence of high molecular weight polyethylene (HMWP) on the viability of osteoblasts and new bone formation in the process of fracture healing, the osteoblasts derived from adult human bone marrow were cultured in HMWP maceration extract and normal culture medium. The viability of the osteoblasts was measured by MTT assay, and the function of the osteoblasts was detected by use of alkaline phosphatase test kit. The locked double-plating (steel plate and HMWP plate) was implanted and fixed at the artificial fracture of distal femur of dogs. Specimens were gained at 3, 6, 9 and 12 weeks postoperatively, examined with macroscopy, microscope and scanning electron microscope (SEM). The results showed that HMWP did no harm to osteoblasts. There is no significant difference in activities of proliferation and alkaline phosphatase between HMWP maceration extract and normal culture medium at each observation time of at 2,4,8, and 14 dyas (P>0. 05). Bone tissue under the implanted HMWP plate manifested no absorption; the new bones formed under the HMWP plate and gradually matured as time went on. It is demonstrated in this study that HMWP has no adverse influence on the viability of osteoblasts and new bone formation and it can be used as internal fixation implant in treating fractures.

[Fingertip replantation after amputation: report of 32 fingers].

OBJECTIVE: To describe the surgical techniques and our experiences in fingertip replantation after amputation. METHODS: On the basis of examination of the anatomic features and the degree of fingertip vascular injury, 32 amputated fingertips in 26 cases were replanted, and flexible revascularization procedures of both artery and vein anastomoses, artery-only anastomosis, arterialized vein and arteriovenous anastomosis were adopted. All the replanted fingertips were trained with comprehensive rehabilitation program. RESULTS: Twenty-nine replanted fingertips survived but 3 failed, and the overall survival rate was 90.06%. During the follow-up lasting from 4 months to 5 years, the 29 replanted fingertips survived with excellent blood supply, good sensory functions, satisfactory shape and functions according to the criteria by Society of Hand Surgery of Chinese Medical Association. CONCLUSIONS: Fingertip replantation after amputation can achieve not only high survival rate but also satisfactory appearance and functions as long as appropriate operative procedures are adopted with comprehensive rehabilitation therapy.