Addition of a Vascular Bundle Accelerates Bone Union in Femoral Bone Defects.

BACKGROUND: The Masquelet method has become increasingly popular for the treatment of bone defects in recent years. In this method, an induced membrane (IM) with abundant blood circulation, stem cells, and osteogenesis-promoting factors is formed by implanting bone cement during the first surgery. This IM stimulates bone formation in the bone defect after implantation of the bone graft during the second surgery. However, the Masquelet method requires two surgeries and thus a longer treatment period. In the present study, we investigated whether bone defects could be reconstructed in a single surgery by introducing a vascular bundle into the bone defect as an alternative to the IM, in addition to bone grafting. METHODS: Thirty-six 12-week-old female Sprague-Dawley rats were used. After creating a 5-mm long bone defect in the femur, a mixture of autologous and artificial bone was grafted into the defect, and a saphenous arteriovenous vascular bundle was introduced. The animals were divided into three groups: the control group (bone defect only), the BG group (bone grafting only), and the BG + V group (bone grafting + vascular bundle introduction). After surgery, radiological and histological evaluations were performed to assess osteogenesis and angiogenesis in bone defects. RESULTS: In the BG + V group, significant bone formation was observed in the bone defect on radiological and histological evaluations, and the amount of bone formation was significantly higher than that in the other two groups. Furthermore, cortical bone continuity was observed in many specimens in the BG + V group. On histological evaluation, the number of blood vessels was also significantly higher in the BG + V group than in the other two groups. CONCLUSION: Our results suggest that the introduction of a vascular bundle in addition to bone grafting can promote bone formation in bone defects and allow for complete bone defect reconstruction in a single surgery.

Skin extension with a digito-lateral flap and early active finger extension training for Dupuytren contracture: A retrospective study.

In the surgical management of Dupuytren contracture (DC), Y-V plasty (YV) and Z-plasty (ZP) are techniques often used for skin extension. However, achieving sufficient skin extension with these procedures alone is often difficult. Therefore, we addressed this issue with an adjunctive digito-lateral flap (DLF) and report the clinical results of the surgery using a DLF in addition to YV and ZP. Fifteen patients with DC (15 affected fingers) underwent partial fasciectomy using a DLF in addition to YV or ZP, and early active finger extension training was performed immediately after the operation. The flap survival rate, preoperative and postoperative extension angle, Tonkin contracture improvement (TCI) rate, and Tubiana staging grades were evaluated. The contracture sites were at 4 proximal interphalangeal (PIP) and 3 metacarpophalangeal (MP) joints of the little finger and 4 PIP and MP joints each of the ring and little fingers. All the flaps survived, and the extension angle improved at the final observation from a preoperative mean of -45° to -3° and -55° to 5° for the PIP and MP joints, respectively. One patient with PIP joint contracture treated in the early stage of the study experienced a persistent 5° limitation of extension, even though the TCI rate was satisfactory (91.9%) and the outcome was "good." Full extension of the joints was achieved in 15 patients, in whom the TCI rate was 100% and the outcome was "very good." This technique was able to solve 3 important steps to achieve full extension: intraoperatively, wound closure, and rehabilitation. We attained and maintained long-term full extension intraoperatively and immediately after surgery and obtained very good treatment results, as shown in this study. In conclusion, highly favorable clinical outcomes were achieved through the combination of a DLF with YV and ZP. Skin extension with a DLF is a useful surgical technique for DC.

Bone Union Enhancement by bFGF-Containing HAp/Col in Prefabricated Vascularized Allo-Bone Grafts.

BACKGROUND: We have developed a prefabricated vascularized allo-bone graft (PVAG) by implanting the saphenous vascular bundles of recipient rats into transplanted donor bones in a flow-through manner. We previously demonstrated that the angiogenetic and bone formative abilities of the PVAG are stimulated by the addition of a basic fibroblast growth factor (bFGF)-containing hydroxyapatite/collagen (HAp/Col). This study aimed to demonstrate that the bone union ability of the PVAG is similarly stimulated by the bFGF-containing HAp/Col composite. METHODS: Sprague-Dawley donor rats (n = 32) and Wistar recipient rats (n = 32) were used in this study. The PVAG was fixed to the femur of the recipient rat using K-wire (dimeter: 0.7 mm) pinning, followed by suturing with a 4-0 nylon suture. Recipients were divided into four groups: with or without vascular bundles, and with or without bFGF-containing HAp/Col. Rats were sacrificed 6 weeks after transplantation, and bone union, bone resorption, and angiogenesis were radiologically and histologically evaluated. RESULTS: Radiological analysis revealed a significant increase in callus formation and union rate, while histological analysis showed a significant increase in bone formation and angiogenesis in the group treated with both vascular bundles and bFGF. Bone resorption did not significantly increase in any of the evaluated groups. CONCLUSION: Osteogenic cells, osteoconductive scaffolds, growth factors, and mechanical environment are known to be important factors in the process of fracture healing. The PVAG developed herein contains osteogenic cells, osteoconductive scaffolds, and growth factors. In addition, the PVAG is rigidly fixed to the fracture site, providing a stable mechanical environment. Together, these four factors contributed to a good bone union. Furthermore, this method did not promote bone resorption. Thus, the addition of a vascular bundle and bFGF-containing HAp/Col makes it possible to create an ideal vascularized allo-bone graft for the reconstruction of massive bone defects.

Effects of VEGF on Prefabricated Vascularized Bone Allografts in Rats.

BACKGROUND: Massive bone defects after wide resection of malignant bone tumors or a serious injury require treatment using vascularized bone grafts. Although cadaveric bone allografts combined with vascularized bone autografts are currently thought to be ideal in terms of size and durability, this treatment requires the scarification of healthy bone tissue. In a previous study, we attempted to improve this situation by prefabricating a vascularized bone allograft in recipient rats. In this study, we added vascular endothelial growth factor (VEGF)-containing hydroxyapatite/collagen composite (HAp/Col) to a prefabricated vascularized bone allograft to stimulate angiogenesis, which is known to be important for bone formation. METHODS: Sprague Dawley rats (n = 50) were used as donors and Wistar rats (n = 50) as recipients. All rats were 9 weeks old. The recipient rats were divided into five groups according to the use of vascular bundles, HAp/Col, and an additive substance (VEGF). The bone allografts collected from the donors were transplanted into the thigh region of the recipients, and a saphenous vein and 10 µg HAp/Col with VEGF were inserted into the bone allografts through the slit. After 4 weeks, the transplanted bone allografts were harvested, and histologic and genetic evaluations were performed in relation to bone formation and resorption. RESULTS: The results showed that, compared with the control group, the implantation of the vascular bundles and VEGF-containing HAp/Col significantly stimulated angiogenesis and bone formation in the rats with the bone allografts. However, histological and genetic evaluations of bone resorption revealed that resorption was not observed in any group. CONCLUSION: These results suggest that VEGF-containing HAp/Col effectively stimulates angiogenesis and bone formation, but not bone resorption, in prefabricated vascularized bone allografts. This method could therefore become a useful tool for treating large bone defects.

Prefabrication of Vascularized Allogenic Bone Graft in a Rat by Implanting a Flow-Through Vascular Pedicle and Basic Fibroblast Growth Factor Containing Hydroxyapatite/Collagen Composite.

Background Basic fibroblast growth factor (bFGF) is known to stimulate bone formation and angiogenesis. Hydroxyapatite/collagen composite (HAp/Col) is also known to have very strong bone conductive activity. In this study, prefabrication of vascularized allogenic bone (allo-bone) graft was attempted in recipients by implanting vascular bundles from recipients into the transplanted allo-bone graft. Furthermore, the effect of bFGF-containing HAp/Col on the prefabricated vascularized allo-bone graft was investigated. Methods In this study, 32 Sprague-Dawley rats were used as donors, and bone grafts were collected from their femora. Thirty-two Wistar rats (recipients) were divided into four groups, and the allo-bone grafts were transplanted into the thigh region. In the experimental groups, one or both of the flow-through saphenous vascular bundles and 100-µg bFGF-containing HAp/Col were implanted into the medullary cavity of the allo-bone grafts. In the control group, neither was implanted. These rats were sacrificed at 4 weeks after transplantation, and bone formation, angiogenesis, and bone resorption in the transplanted allo-bone grafts were evaluated histologically and genetically. Results Bone formation and angiogenesis in the transplanted allo-bone graft were effectively stimulated by implanting vascular bundles or bFGF-containing HAp/Col on both histological and genetic evaluations compared with the control group. The most significant stimulation was observed in the group in which both were implanted. Bone resorption was not stimulated in any group. Conclusion By implanting a flow-through vascular bundle and bFGF-containing HAp/Col, an ideal vascularized allo-bone graft that had high bone formative and angiogenetic activities and did not stimulate bone resorptive activity was prefabricated.

Localized type Volkmann's contracture treated with tendon transfer and tension-reduced early mobilization: A case report.

RATIONALE: For localized type Volkmann's contracture, in which degeneration of the flexor digitorum profundus (FDP) muscle to one or two fingers and restriction of finger extension occur, dissection or excision of the affected muscle is usually recommended. However, these surgical procedures need relatively wide exposure of the muscle, because the FDP muscle is in the deep portion of the forearm. PATIENT CONCERNS: In this report, the case of a 35-year-old woman with localized type Volkmann's contracture is presented. Her left forearm had been compressed with an industrial roller 4 months earlier, and severe flexion contracture of the long finger and mild flexion contracture of the ring finger developed gradually. DIAGNOSES:: localized type Volkmann's contracture. INTERVENTION: Five months after the injury, transection of the FDP tendon to the long finger and transfer of the transected tendon to the FDP tendon to the index finger was performed after adjusting the tonus of these two tendons using a small skin incision. This procedure was followed by a tension-reduced early mobilization technique in which a tension-reduced position of the tendon suture site was maintained by taping the long finger to the volar side of the index finger, and then immediate active range of motion (ROM) exercise was started. OUTCOMES: Within 9 weeks after surgery, full ROM had been regained. LESSONS: Using the treatment procedure presented in this case report, a good clinical result was obtained in a minimally invasive manner.