Purpose of the study: Fixing the pedicles can be difficult to achieve during surgical treatment of scoliosis involving the thoracic spine because of the vertebral rotation raising the risk of neurological and vascular disorders. Use of extrapedicular thoracic screws has been proposed for more adapted and safe fixation. No clinical data has been published concerning the safety of these screws.

Material and methods: This multicentric retrospective clinical and radiological study included 467 thoracic screws in 34 patients operated for scoliosis. Neurophysiological monitoring was used for all procedures. Screws were positioned free hand without radioscopic control. Pedicular screws were inserted in T10, T11, T12. Extra-pedicular screws were inserted for thoracic vertebrae above T10 to T4. Correction was achieved with rods bent in situ. The purpose of this study was to evaluate the position of the thoracic screws within the vertebral body and in relation to the great vessels and the cord. The position of the screws in the thoracic spine was studied by two independent observers reading multiple thin-slice CT images. The observers noted malposition as: 1) penetration into the canal more than 2 mm, 2) less than 1 cm hold in the vertebral body, 3) screw protrusion more than 2 mm beyond the vertebral cortical.

Results: Screw malposition was observed for 9 of 161 pedicular screws (5.4%) and for 21 of 306 (6.8%) thoracic screws. None of the screw malpositions had a clinical expression. There was one episode of thoracic effusion associated with thoracoplasty. Two patients required revision (one for poor indication and one for disincarceration). There were no postoperative deep infections. Three cases of intercostals neuralgia subsided within three months.

Conclusion: Insertion of thoracic screws for fixation and correction is a useful technique with few complications. It enables better 3D correction and better control of the deformation. Screw malposition in this series was similar to that observed with classical pedicular techniques. There was no major complication associated with thoracic screws.

Purpose: In paediatric patients, autografts are limited by the quantity of available bony tissue in donor regions, the need for a second incision, the longer surgical time, and donor site morbidity. Bone substitutes would be an advantage in many cases. Serum and platelet autologous growth factors favouring osteo-induction can be obtained readily. When used in conjunction with osteoconductive materials, they can favour bone growth. The purpose of this work was to evaluate the use of combined autologous growth factors (AGF) and hydroxyapatite (HA) in paediatric patients instead of autologous grafts.

Material and methods: This prospective study was conducted in 14 children (16 grafts), nine boys and six girls, mean age 9.4 years. These children required bone grafting related to femoral osteotomy, osteomyelitis, benign cystic tumours, bone nonunion, triple arthrodesis with osteopenia, and insufficient autologous graft material. The AGF-HA combination with human thrombin was used in all cases. AGF was prepared after fractioning autologous blood according to the child’s blood volume, height and weight. A platelet ultraconcentrate was added to thrombin (500 IU) and HA (500 R) at the time of implantation. Mean preparation time was 20 minutes. An autologous graft was not used in any of the children.

Results: There were no cases of superficial or deep infection after implantation. Bone healing as assessed clinically and radiologically was obtained in eleven weeks on average (range 8–16) except in two cases (11%).

Discussion: The AGF-HA combination is a useful alternative to autologous bone grafting in children. It is a simple technique which accelerates bone healing and HA integration. There were no cases of rejection.

Conclusion: 1) In children, this method is a valid alternative which avoids the need for bone harvesting and the corresponding morbidity. 2) Use of AGF-HA in combination does not transmit infection, does not lengthen surgery time, and is an interesting alternative to autologous or heterologous bone grafting.