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.

Purpose: The role of arthroscopic treatment for degenerative knee joint disease remains controversial. The aim of this work was to evaluate the efficacy of arthroscopic debridement and to establish its indication for the treatment of knee osteoarthritis in patients aged less than 50 years.

Material and methods: Arthroscopic debridement was performed from 1994 to 2002 in 192 patients, 72 men and 120 women, mean age 59 years (51–75). We noted clinical history, particularly conditions contraindicating major surgery, and prior lower limb trauma, particularly involving the same knee. Patient weight and activity level were considered. The preoperative work-up included a functional examination (Freeman), and a radiographic study used to class the osteoarthritis as early, moderate or advanced and measure the knee axis. We performed joint wash out in all cases associated with different debridement procedures. Chondropathy was evaluated with the Marshall classification. A new functional evaluation and subjective evaluation was performed at last follow-up.

Results: Severe disease was present in the history of 5.2% of the knees; 9.3% had had prior surgery and 82% presented moderate osteoarthritis, mainly involving all three compartments. Type II or III chondropathy was found in 92% of knees. At mean follow-up of 28 months (5–108), the mean function score improved from 69.4/110 preoperatively to 89.5/110 and 75.4% of patients considered their knee had improved. Five patients required secondary arthroplasty. Poor outcome was associated with type III or IV chondroplasty involving the three compartments and the presence of the mentioned history. Age was not correlated with poor outcome.

Discussion: We studied a population with overt osteoarthritis who were treated with a minimally aggressive method, mainly for palliation. Only 2.6% underwent total arthroplasty after arthroscopic treatment. There was a clear improvement in function, mainly pain relief. The large majority of the patients were satisfied with the outcome and did not require further medical treatment except occasionally. The less satisfactory results were obtained in patients with more advanced disease who could not undergo arthroplasty because of concomitant medical conditions.

Lumbar spine fusion has increasingly been used as a lumbar pain treatment. Its frequency is of 0.03 to 0.6% fusions in the population over 65 years of age. The first factor of this increase is the use of more accurate non-invasive diagnostic mediums as CAT or MRI.

The second increasing factor has been the pedicular fixation introduced by Roy-Camille. Recently the use of interbody cages has made easier the correction of disc collapse, instability and sagital deviations. Both posterior and anterior fixation is used with different sort of approaches, according to the particular patient or training of the surgeon. The systematic use of fluoroscopy and navigational devices rends accurate the use of internal fixation. The third factor increasing the frequency of spinal fusion is the raising demography of well-trained spinal surgeons’ perhaps one of the most influential reasons of the higher success rates.

Notwithstanding those advances, it remains a number of failures. The rate of reoperations after fusion has been assessed to be 17.4% over 4 postoperative years. The advances in the knowledge of cellular signals and factors of ossification can diminish the failed bone fusions. The use of different sorts of bone-grafts, bone-substitutes and bone enhancers has rendered easier the postoperative regimes. The rhBMP’ use with specific carriers as sole fusion initiator has been successfully introduced and inhibitors of bone growth as nicotine or NSAIDs identified.

But the same factors of control of vertebral motion are the cause of errors than can be the origin of root lesions. The bulky hardware is a co-operative factor in the onset of septic failures. And the surgeon’s demography origins a higher number of borderline indications.

Even when the bone fusion has been successful, the pain may continue to ruin the life of the patient. Two mechanisms have been identified as origin of the pain, one extra and one intradural.

The compressive extradural lesions are caused mainly by the action of progressive stenoses or by the disruption of the pedicular wall by badly placed screws.

As for defective screw’s trajectory, the most dangerous points are mainly the pedicle’s medial or inferior corticals. In the intraforaminal trajectory the dural sleeve of the lumbar root may be mangled too, suffering a mixed mechanicalbiological mismanagement. Even without laceration a burst cortical or the metal contact can be the origin of root irritation or even palsies. These lesions are present in most series in between 1 and 10% of the screws, depending of the surgical experience. The use of navigational devices finds in this technique his principal indication.

The CAT usually diagnoses the misplaced screws. The artefacts caused by stainless steel are the reason of banning this metal for spinal devices. When doubt the pain origin can be proved by electromyographical analysis. The electrical stimulus of the screw with a 0.2 millisecond pulse of 5 – 10 mA DC signals a violated pedicle wall. The treatment of these lesions is always the removal of compressive hardware. When a non-union compounds the root compression a TLIF with cage plus posterolateral fusion with posterior instrumentation, allows the liberation of the root without entering the compromised canal.

The compression of the dural sac by recurrent stenosis was frequent in posterior fusions. The lamina thickens by the transmission of charges through this bony continuum. Nowadays it can be yet seen with lamina decortication and bone grafts stocked between the rods and the base of the spinous process. The CT myelogram shows the lesion. The extraction of the hardware and resection of the redundant bone inside the canal, can resolve the compression. The most fearful lesions are the peridural and the intradural fibrosis caused by the operative mishandling of the dural sac or by septic epidural episodes. The neurologic lesions are often irreversible. The treatment is the most difficult and the outcomes the gloomiest of the spinal surgery. The best treatment is the prevention by delicate handling of the dural sac. Suture with titanium micro-clips must be done in all the dural wounds. Disc resection adjoining articular fusion in the treatment of stenotic canals must be avoided, to prevent a cicatricial circle. Abstention of foreign bodies inside the canal, use of bipolar cautery and soluble haemostatic substances to stop the intra-canalar bleeding, are the means of preventing the peridural fibrosis. Corticoids locally or covering the dura with a thin layer of anti-adhesive gel is a good prevention of adherences. The wounds of the dura can produce too a leakage of CSF leading to a compressive myelomeningocele if intracanalar. Wear titanium particles can be found in defective constructs. The motion between rod and screws can produce them. If the particles enter the canal they can produce both compression and fibrosis.

In the case intradural adherences blocking the roots in bundles, little can be done. Once secured the immobilisation of the level by a good extracanalar bone-fusion, the use of electrical interference electrodes in contact with the affected roots is the only solution. Some aid can be expected with the use of antiproliferative cytokines as interferon gamma or reverse-transcriptase inhibitors as Suramin, administered after a surgical cleaning of the fibrosis. With all the inconveniences of these treatments yet they allow a modicum of hope.

Purpose: The purpose of revision surgery for a hip arthroplasty is to re-establish a stable assembly, recover bone stock, and re-establish the mechanical centre of the joint. The purpose of our work was to evaluate clinical and radiographic mid-term outcome of a press-fit cup on bone grafts for cup revision of total hip arthroplasty (THA).

Material and methods: We revised 55 hip arthroplasties in 1995 and 1996, for revision of the cup with reconstruction in 42 cases. For 16 patients (ten women and five men), we used the press-fix technique on bone grafts. Mean patient age was six years (range 34–82) and mean follow-up was 70 months (range 62–86). Besides four partial arthroplasties, the revised components were six screwed cups, five cemented cups and one press-fit cup. The reason for the first intervention was hip degeneration in most of the patients. We used the posterior approach in all patients. Bone bank stock was used, ground in fifteen cases and structured in two. Thirteen cups were coated with hydroxyapatite, three with a porous coating. Four components were reinforced with screws. We evaluated bony defects with the Paproski classification. The clinical aspect was assessed with the

Postel-Merle-d’Aubigné scale. For the radiographic analysis, we considered the situation of the implant after revision and possible later displacement. For the graft tissue, we studied integration in the De Lee-Charnley zones.

Results: None of the cups required revision. The component was well integrated in 62.5% of the patients. Function score improved from 11.5/18 preoperatively to 15/18 postoperatively then 15.9/18 at last follow-up. Subjectively patient satisfaction was good or excellent in 81% of the cases.

Discussion: This technique reinforces the bone stock since it preserves the bone present and adds new bone, facilitating integration. Likewise, it does not require changing the functional centre of the hip, good integration of the implant favours good assembly. Functional and subjective outcomes are good.

Conclusion: After at least six years follow-up, press-fit bone grafting for revision procedures is a promising technique.