Objective To summarize the effect of self-setting CPC on the repair of bone defect after tumor resection in children. Methods From December 1998 to December 2006, 32 patients with benign bone tumor were treated, and the bonedefect was repaired by CPC. Among them, there were 21 males and 11 females, aged 4-14 years old (9.8 on average). The course of disease was 3-18 months. There were 12 cases of non-ossifying fibroma, 8 of bone cyst, 7 of osteoid osteoma and 5 of fibrous dysplasia. The bone defect was located in femur in 15 cases, in tibia in 8 cases, in humerus in 6 cases and in other positions in 3 cases. The range of bone defect was 2.0 cm × 1.5 cm × 1.0 cm - 10.0 cm × 5.0 cm × 4.0 cm. CPC spongiosa granules of 3-23 g were filled in 26 cases, including 3 children with pathologic fracture and internal fixation with plate, and injectable CPC of 5-20 mL was filled in 6 bone cyst cases. Results Thirty-two patients obtained heal ing by first intertion. All the patients were followed up for 12-48 months (23.5 months on average). No allergic reaction, toxicity, rash or high fever was found after operation. There was no pain or pruritus at the incisions. The X-ray films showed that the implanted CPC began to fuse with the host bone 4-9 months (7 month on average) after operation. The internal fixation was removed within 6-12 months of operation. And CPC spongiosa granules were absolutely absorbed within 8-36 months of operation. However, injectable CPC could be found 4 years after operation. The children’s l imbs could do normal exercises. Finally, bone matrix grew well and no recurrence was found. Conclusion CPC in repairing bone defect after benign bone tumor in children is a safe, economical, convenient and non-toxic method.
Objective To develop a high-accuracy, better-safety and low-cost cervical pedicle locator system for guiding cervical pedicle screw placement. Methods Cervical pedicle screw locator system was made of stainless steel. Ten cervical specimens from voluntary donation were divided into two groups according to compatibil ity design: control group inwhich 60 screws were planted into C2-7 by free hand; and experimental group in which 60 screws were planted into C2-7 under the guidance of three-dimensional locator system. The condition of screw insertion was observed and the accuracy was evaluated by the integrity of pedicle walls. Results In the control group, 32 screws (53.33%) were placed inside the pedicles and 28 (46.67%) were outside; 9 screws (15.00%) led to nerve root injury, 5 screws (8.33%) caused vertebral artery injury and no spinal cord injury occurred; and the qual ification ratio of screw insertion was 76.67% (excellent 32, fair 14, poor 14). While in the experimental group, 54 screws (90.00%) were placed inside the pedicles and 6 (10.00%) were outside; 1 screw (1.67%) caused vertebral artery injury and no nerve root injury and spinal cord injury occurred; and the qual ification ratio of screw insertion was 98.33% (excellent 54, fair 5, poor 1). There was significant difference between the two groups (P lt; 0.05). Conclusion Cervical pedicle screw locator system has the advantages of easy manipulation, high accuracy of screw placement and low cost. With further study, it can be appl ied to the cl inical.