Objective To investigate the clinical results of allograft and sural neurovascular flap in repairing calcaneus and skin defects.Methods From February 1996 to December 2002, allograft and sural neurovascular flap were used to repair calcaneusand skin defects in 6 cases. The causes included road accident in 3 cases, strangulation in 2 cases and crashing object in 1 case. The defect locations were at theback of the calcaneus( 1/3, 1/2 and 2/3 of calcaneus in 3 cases, 2 cases and 1case respectively). The flap area ranged from 6 cm×7 cm to 12 cm×17 cm. Results The flaps survived completely in 4 cases; the distal flaps necrosed partly in 2 cases and the wound healed by dressing. The postoperative X-ray films showed that the repaired bone and joint had normal position and the arcus plantaris recovered. After a follow upof 6 months to 3 years all the patients were achieved bone union in allograft and had no complications of absorption, infection and repulsion. The weightbearing and walking functions were restored and the injured foot obtained a satisfactory contour. After 36 months of operation, the sensory recovery of foot occurred. Conclusion The used-allograft iseasy to be obtained and arcus plantaris is easy to recover. The reversesural neurovascular- flap in repairing calcaneus and skin defects has the following advantages: the maintenance of blood supply for injured foot, the less dangerous operation, the simple procedure, the recovery of walking function, and the good appearance and sensation.
Objective To evaluate the immunological reaction and the outcome of allogeneic chondrocyte transplantation in repairing articular cartilage defects in porcins. Methods Full articular cartilage from the knee of two Shanghai white porcins about one-month-old was removed and cut mechanically, digested by 0.25% trypsin and 0.2% type Ⅱ collagenase and cultured in 10％ DMEM medium. Defects of 0.5 cm×0.5 cm involving the subchodral bone were created in both the left and right femur condyloid in 8 two-month-old Yunnai bama porcins. Allogeneic chondrocyte transplantation were implanted in defects at a density of (1.0-2.0)×106,0.2 ml. The lymphocytes from the receivers’ blood were collected before transplantation and after 3, 5, 7 and 12 weeks of transplantation, then mixed with allogeneic chondrocytes to determin the lymphocyte stimulation index(SI) in vitro. The histological observation in vivo was made after 5, 7 and 24 weeks of transplantation. Results Lymphocyte SI at 3, 5, 7 and 12 weeks(1.457±0.062,1.739±0.142,1.548±0.047，1.216±0.028) after transplantation was higher than that before transplantation(1.102±0.034，Plt;0.05). SI began to increase in the 3rd week and reached the peak value in the 5th week, then gradually declined at the 7th and 12th weeks, showing significant differences when compared with in the 5th week (Plt;0.05). Inflammation and lymphocytes infiltration could be seen in subchondral bone and the intergration area between repair tissue and normal cartilage in the 5th week, and then decreased and limited in subchondral bone in the 7th week. Defects were filled with cartilage tissue, which had good intergration with subchondral bone at 24 weeks after transplantation. Conclusion Immunological reactions can be found at early stage of allogeneic chondrocyte transplantation and then decreased with the time, the fullthickness articular cartilage defects could be repaired mainlywith hyaline cartilage by the allogeneic chondrocyte transplantation. This may provide a new method to repair articular cartilage defects clinically.
Objective To give a prel iminary experimental evidence and to prove chitosan and allogeneic morsel ized bone as potential bone substitutions in repairing rabbit radius segmental defect. Methods Chitosan and allogeneic morsel ized bone were mixed with various ratios (1 ∶ 5, 1 ∶ 10, 1 ∶ 25, 1 ∶ 50, and 1 ∶ 100). After preparation, the physicaland chemical properties of the composites were prel iminary detected; the composites at the ratios of 1 ∶ 50 and 1 ∶ 25 had good physical and chemical properties and were used for the animal experiment. The radius segmental defects of 15 mm in length were made in 50 adult New Zealand white rabbits (weighing 2.5-3.0 kg), then the animals were divided into 2 groups. In groups A and B, chitosan/allogeneic morsel ized bone composites were implanted at the ratio of 1 ∶ 50 and 1 ∶ 25, respectively. After 1, 2, 4, 8, and 12 weeks of operation, the gross, histological, immunohistochemical observations were performed. Before the rabbits were sacrified, X-ray films were taken; the serum calcium and alkal ine phosphatase (ALP) concentration were measured; and the biomechanical measurement was carried out at 12 weeks. Results The results of gross observation were essentially consistent with those of the X-ray films. The histological observation showed that the bone formation was earl ier in group A than in group B; the amount of new bone formation in group A was more than that in group B; and the bone forming area in group A was bigger than that in group B (P lt; 0.05) at 4 and 8 weeks after operation. The immunohistochemical staining showed that vascular endothel ial growth factor and insul in-l ike growth factor receptor II proteins expressed in the cytoplasm of 2 groups after 4 and 8 weeks, and the expression in group A was higher than that in group B (P lt; 0.05). There was no significant difference in the serum calcium concentration between 2 groups at each time point (P gt; 0.05). After 4 and 8 weeks, the ALP concentration in group A was significantly higher than that in group B (P lt; 0.05). After 12 weeks, the radius maximum bending loads of groups A and B were (299.75 ± 27.69) N and (278.54 ± 17.09) N, respectively, showing significant difference (t=4.045,P=0.002). Conclusion The composite of chitosan and allogeneic morsel ized bone has good osteogeneic activity and can beused as a bone tissue engineering scaffold, and the optimum ratio of chitosan to allogeneic morsel ized bone was 1 ∶ 50.
Objective To evaluate the effects of composite bone in strategy of tissue engineering on bone defect repair in rats. Methods Sixteen matured Wistar rats (male or female, weighing 250-300 g) were used to prepare platelet lysate (PL). PL/allogeneic decalcified bone granules (ADBG)/Col I (PAC) and ADBG/Col I (AC) were prepared by mixing Col Igel ADBG with or without PL. BMSCs of 8 Wistar rats (male or female, weighing 250-300 g) were isolated and cultured. The 5th passage of BMSCs were co-cultured with PAC at the density of 1 × 106 cells/mL to fabricate the tissue engineered composite PACB in vitro. Forty healthy Wistar rats were made bilateral bone defects in femoral condyles and divided into 4 groups (A, B, C and D, n=10). The defects were filled with equivalent PACB, PAC, AC and Col I in groups A, B, C and D respectively. At 4 weeks, the defect repair was evaluated with radiology, histology, ALP biochemical tests. Results At 4 weeks, the bone density measurement was (7.31 ± 0.54), (4.36 ± 0.67), (2.12 ± 0.47), and (1.09 ± 0.55) pixels in groups A, B, C, and D, respectively. The area of new bone formation in defect area under single view was (412.82 ± 22.31), (266.57 ± 17.22), (94.34 ± 20.22), and (26.12 ± 12.51) pixels in groups A, B, C and D respectively. The ALP contents in femoral condyles were (94.31 ± 7.54), (69.88 ± 4.12), (41.33 ± 3.46), and (21.03 ± 3.11) U/L, respectively. The above indexes of group A were significantly higher than those of groups B, C or D (P lt; 0.05). Three-color flow cytometry assay showed that the T lymphocyte subsets of CD3+CD4+CD8-, CD3+CD8+CD4-, and the ratio of CD4/CD8 displayed no significant difference among four groups (P gt; 0.05). Conclusion Tissue engineered bone PACB is capable to promote the bone defect repair.
Objective To evaluate the cl inical results of allogeneic bone graft for interbody fusion in cervical tuberculosis. Methods Between January 2000 and January 2008, 30 cases of cervical tuberculosis were treated with allogeneic (group A, n=15) or autologous (group B, n=15) il iac crest bone graft combined with anterior fixation after radical debridement. In group A, there were 8 males and 7 females with an average age of 38 years; the disease duration was 6 to 14 months; the preoperative kyphosis Cobb angle was (8.6 ± 11.3)°; the preoperative Japanese Orthopaedic Association (JOA) score was 13.0 ± 3.1 for neurological function; and the length of bone graft was 32 mm on average. In group B, there were 9males and 6 females with an average age of 42 years; the disease duration was 4 to 17 months; the preoperative kyphosis Cobb angle was (4.9 ± 7.4)°; the preoperative JOA score 12.3 ± 4.2; and the length of bone graft was 34 mm on average. There was no significant difference in general data between 2 groups (P gt; 0.05). Results The operation time and bleeding volume in group A were significantly less than those in group B (P lt; 0.05). Wound effusion were found in 2 cases of group A, and the other incisions healed by first intention. No infection occurred in group B. In group A, 13 cases were followed up 12-48 months; in group B, 14 cases were followed up 13-46 months. The time of bone graft heal ing in group A [(7.6 ± 2.1) months] was significantly longer than that in group B [(4.2 ± 1.1) months] (t=2.773, P=0.005). The kyphosis Cobb angles were significantly improved at 6 months and last follow-up after operation in 2 groups when compared with that before operation (P lt; 0.05), but no significant difference was found between 2 groups at different time after operation (P gt; 0.05). There was no significant difference in JOA score at 6 months after operation between group A (14.1 ± 2.6) and group B (14.3 ± 2.4) (t=1.655, P=0.162). The improvement rate for neural function were 83.7% in group A and 87.8% in group B, showing no significant difference (χ2=3.150, P=0.071). There was no loosening of internal fixation and recurrence of tuberculosis in 2 groups during follow-up. Five cases had chronic pain at il iac donor sites in group B. According to Bridwell et al. evaluation standard, the bone fusion was satisfactory in 11 cases (84.6%) and unsatisfactory in 2 cases (15.4%) in group A, and was satisfactory for all in 14 cases (100%) in group B. The satisfactory rate of bone fusion showed no significant difference between 2 groups (χ2=2.680, P=0.115).Conclusion Allogeneic bone grafting has a good cl inical result for spinal fusion in cervical tuberculosis surgery, which can treat tuberculosis bone defect effectively.
Objective To study the effect of the allogeneic bone sheet that has been treated by the freezedrying and radiation sterilization in preventing the epidural adhesion after laminectomy in sheep. Methods Laminectomy was performed on L3,4and L4,5 of 12 adult male sheep. Afteroperation, one site of L3,4 or L4,5was covered by the allogeneicbone sheet in “H” shape after the freeze-drying and radiation sterilization treatment; and the other site was used as a control. The sheep were killed and the specimens were retrieved at 4，8，12，16，20 and 24 weeks after operation to observe the scar formation process. X-ray andCT scan were performed in the segments of L3,4and L4,5at 4 and 24weeks. Results Four weeks after operation, the position and the shape of the allogeneic bone sheet were good in condition, and no lumbar spinal stenosis or compression of the dura was found in the experimental sections. Twentyfour weeks after operation theexamination on the experimental sections revealed that the vertebral canal reconstruction was completed, the allograft was absorbed almost completely, and inosculation with the lamina of the vertebra and the shape of the lumbar spine were good, with no fibroid tissues found in the epidural area. Compared with the control segment, the dura adhesion degree in the laminoplasty segment was significantly decreased (Plt;0.01), and the dura sac remained in a good shape. There was no obvious compression on the dura. Conclusion The allogeneic bone sheet after the treatment of freeze-drying and radiation sterilization can effectively reduce the scar formation after laminectomy and prevent postoperative recurrence of the spinal stenosis.
OBJECTIVE: To construct tissue engineering bone with bio-derived materials and bone marrow stromal cells (MSCs), and to investigate the effect of allogeneic engineering bone implants on healing of segmental bone defects. METHODS: MSCs being aspirated aseptically from tibial tuberosities of young rhesus monkeys were induced into osteoblasts in vitro and then were cultured and marked with 5-bromo-2-deoxyuridine (BrdU). Tissue engineering bones were constructed with these labeled osteoblasts being seeded onto bio-derived materials made from fresh human bones which were treated physically and chemically, Then the constructs were implanted in 15 allogeneic monkeys to bridge 2.5 cm segmental bone defects of left radius as experimental groups, bio-derived materials only were implanted to bridge same size defects of right radius as control group. and, 2.5 cm segmental bone defects of both sides of radius were left empty in two rhesus monkeys as blank group. Every 3 monkeys were sacrificed in the 1st, 2nd, 3rd, 6th and 12th weeks postoperatively and both sides of the implants samples were examined macroscopically, histologicaly, and immunohistochemicaly. The two monkeys in blank group were sacrificed in the 12th week postoperatively. RESULTS: Apparent inflammatory reactions were seen around both sides of the implants samples in the 1st, 2nd, 3rd weeks, but it weakened in the 6th week and disappeared at the 12th week. The labeled osteoblasts existed at the 6th week but disappeared at the 12th week. The bone defects in experimental group were repaired and the new bone formed in multipoint way, and osteoid tissue, cartilage, woven bone and lamellar bone occurred earlier when compared with control group in which the bone defects were repaired in ’creep substitution’ way. The bone defects in blank group remained same size at the 12th week. CONCLUSIONS: Engineering bones constructed with bio-derived materials and MSCs were capable of repairing segmental bone defects in allogeneic monkeys beyond ’creep substitution’ way and making it healed earlier. Bio-derived materials being constituted with allogeneic MSCs may be a good option in construction of bone tissue engineering.
Objective To investigate the value of computer-aided design (CAD) in defining the resection boundary, reconstructing the pelvis and hip in patients with pelvis tumors. Methods Between November 2006 and April 2009, 5 cases of pelvis tumors were treated surgically using CAD technology. There were 3 males and 2 females with an average age of 36.4 years (range, 24-62 years). The cause was osteosarcoma, giant cell tumor of bone, and angiosarcoma in 1 case, respectively,and chondrosarcoma in 2 cases. According to the Enneking system for staging benign and mal ignant musculoskeletal tumors, regions I, I + II, III, IV, and I + IV is in 1 case, respectively. According to the principle of reverse engineering, 5 patients with pelvis tumors were checked with lamellar CT/MRI scanning, whose two-dimensional data were obtained in disease area. The three-dimensional reconstruction of pelvic anatomical model, precise resection boundary of tumor, individual surgical template, individual prosthesis, and surgical simulation were precisely made by computer with CAD software. Based on the proposal of CAD, the bone tumor was resected accurately, and allograft il ium with internal fixation instrument or allogeneic il ium with personal ized prosthetic replacement were used to reconstruct the bone defect after tumor was resected. Results The operation was successfully performed in 5 cases. The average operation time was 7.9 hours, and the average blood loss was 3 125 mL. Hemorrhage and cerebrospinal fluid leakage occurred in 1 case, respectively, and were cured after debridement. Five patients were followed up from 24 to 50 months (mean, 34.5 months). All patients began non-weight bearing walk with double crutches at 4-6 weeks after operation, and began walk at 3-6 months after operation. Local recurrence developed in 2 patients at 18 months after operation, and resection and radiotherapy were performed. According to International Society of Limb Salvage criteria for curative effectiveness of bone tumor l imb salvage, the results were excellent in 2 and good in 3. Conclusion The individual surgical template, individual prosthesis, and surgical simulation by CAD ensure the precision and rel iabil ity of pelvis tumors resection. The CAD technology promotes pelvis tumor resection and the reconstruction of pelvis to individual treatment stage, and good curative effectiveness can be obtained.
Objective To explore the clinical application of allogeneic bone transplantation. Methods Related literatures on clinical application of various allograft bone materials of the past 5 years were extensively reviewed. Results The allografts could be processed into various kinds of transplanting materials, such as small blocks, large segments, morselised or granular material, and bone ring, so that they could be applied to bone defect filling, prosthesis revision, limb preservation after tumor resection, and joint fusion. All these applications ended up with good clinical results. However, complications resulted in thestructural transplantation of large block bones could be overlooked. Conclusion The main advantage of bone allograft is that it can be integrated with host bone and be remodelled, so as to reconstruct bone structure and function. How to accelerate their integration and remodelling while exerting normal functions is the problem that requires solution.
OBJECTIVE: To investigate the repairing effect of transplantation of allogeneic fetal bone in combination with a covering cryopreserved periosteal allograft to bone defect. METHODS: Twenty Long-eared white male rabbits were chosen as experimental model of bilateral 12 mm combined bony and periosteal radial defect. Cryopreserved allograft periosteum with allogeneic fetal bone were implanted in the left defect as experimental side and fetal bone was simply transplanted in the right defect as control side. Bone repair process in the two groups were compared by macroscopy, microscopy, roentgenograms and the contents of calcium and phosphate in the defect area at 2, 4, 8 and 12 weeks after transplantation. RESULTS: There was significant statistic difference in the contents of calcium and phosphate between the experimental and control sides at 4, 8 and 12 weeks after transplantation (P lt; 0.05). With time passing by, the contents of calcium and phosphate have the increasing trends. In the experimental group, lamella bone was seen and medullary canal recanalized at 8 weeks postoperatively. The histological section showed the bone lacuna and lamella bone were formed. CONCLUSION: It suggests that allogeneic fetal bone in combination with a covering cryopreserved periosteal allograft can promote bone repair, and allogeneic fetal bone is excellent bone substitute.