Introduction

Degenerative disc disease results from mechanical alteration of the intervertebral disc. Biochemical modifications of the nucleus matrix are also incriminated. Furthermore, genetic predispositions as well as vascular factors have been advocated in the process of disc degeneration. A relationship between sciatica and Propionibacterium acnes has been described. However, it remains unclear if the hypothesis of a subclinical spondylodiscitis might play a role in the pathophysiology of degenerative disc disease. The purpose of this study was to analyze the possible presence of bacteria in lumbar discs of patients with degenerative disc disease.

Purpose of the study: The in situ contournage technique can be used to correct the 3D spinal deformity resulting from scoliosis; the manoeuvres enable rotational corrections, medialisation, and kyphosis and lordosis of strategic segments of the spine. A preliminary study identified a prolonged zone of thoracolumbar sagittal rectitude in thoracic, double major and lumbar scoliosis, indicating the vertebrae with the maximal rotation and the zones of hypokyphosis and hypolordosis. The purpose of the present study was to analyse the correction and sagittal balance of these segments after in situ contournage.

Material and methods: The pre- and postoperative radiographs of 54 patients (48 female, 6 male, mean age 21 years, mean follow-up 8 years) with idiopathic scoliosis (36–104) were analysed with Spineview. The types of curvatures, the levels included in the sagittal rectitude and the vertebrae with the maximal rotation were determined. The kyphosis was measured on T4-T12, T4-T8 and T9-T12. Lordosis was measured on L1-S1, T12-L2, L3-S1. Tilt on T1 and T9 and sacral slop as well as pelvic version and incidence were determined.

Results: Three characteristic configurations were analysed: thoracic curvature with sagittal rectitude T8-L1 and maximal rotation at T7-T8, double major curvatures with sagittal rectitude T9-L2 and maximal rotation at T8-T9 and L2-L3, and lumbar curvatures with sagittal rectitude T12-L4 and maximal rotation at L1-L2. After posterior instrumentation, the T4-T12 hyperkyphosis decreased on average from 24.1 to 17.4° (p=0.0001) and the T9-T12 hypokyphosis increased from 3.6 to 8.6° (p=0.0001) for the thoracic and double major curvatures. The T12-L2 hyperlordosis increased from 6.6 to 10.3° (p=0.027) and the L3-S1 lordosis decreased from 42.1 to 38.9° (p=0.463) in the lumbar and double major curvatures. Tilts, sacral slope, and pelvic version and incidence did not vary significantly.

Conclusion: The prolonged thoracolumbar sagittal rectitude exhibits three distinctive configurations. Each configuration indicates the level of maximal rotation at the superior or inferior end. It enables a decomposition of the overall thoracic kyphosis into a superior segment of hyperkyphosis and an inferior segment of hypokphosis and to identify a zone of superior lumbar hypolordosis. In situ contournage corrects the vertebral rotation, the kyphosis and the lordosis and acts on the strategic vertebrae. The rectitude can be used to better identify the zones requiring correction in order to optimise the balance between the thoracic kyphosis and the lumbar lordosis while improving vertebral rotation by traction or compression.

Purpose of the study: Prolongation of the phyisiological sagittal rectitude of the thoracolumbar junction (T11-T1) is often observed in thoracic, double major and lumbar idiopathic scoliosis. The purpose of this study was to check the potential relationship between vertebral rotation, type of curvature in the frontal plane, and the observation of sagittal rectitude exceeding four vertebrae.

Material and methods: The preoperative radiographs of 54 patients (48 female, 6 male, mean age 21 years) with idiopathic scoliosis were analysed with Spineview. The type of curvature: thoracic, double major or lumbar (Lenke 1, 3 or 5) and the Cobb angles were noted. The levels included in the zone of sagittal rectitude, the thoracic kyphosis, the lumbar lordosis, the sacral slope, the pelvic incidence and version, the T1 to T9 tilts were noted on the lateral view. Vertebral rotation was analysed for all thoracic and lumbar vertebrae using the method described by Perdriolle, Nash and Moe on the anteroposterior radiographs. The axial rotation was measured on the scanner.

Results: Curvatures ranged from 36 to 104° (mean 59°). Fifty-two patients had a flat or concave back. Mean T1 tilt was 3°; it was 6° at T9. The pelvic incidence was 49°, the sacral slope 40°, the pelvic version 9°. The detailed analysis demonstrated zones of inferior thoracic hypokyphosis, and superior lumbar hypolordosis resulting in sagittal rectitude (5–7 vertebrae). The maximal vertebral rotation was situated at the superior part of the hypokyphosis or the inferior part of the hypolordosis. Three configurations were identified: 27 thoracic curvatures (Lenke 1) with cranial prolongation of the sagittal rectitude (T8-L1) and maximal rotation at T7-T8; 21 double major curvatures (Lenke 3 with cranial and caudal prolongation (T9-L2 and maximal rotation at T8-T9 and L2-L3 respectively; and 6 lumbar curvatures (Lenke 5) with caudal prolongation (T12-L4) and maximal rotation at L1-L2.

Conclusion: Thoracolumbar sagittal rectitude can be prolonged with three geometric configurations related to the type of thoracic, double major and lumbar curvatures. This zone of rectitude indicates the level of the maximal vertebral rotation at is superior or inferior extremity. It also reflects the zones of segmental hyperkyphosis and hypolordosis that need to be corrected during the surgical treatment of the scoliosis.

Introduction: The lumbosacral medulla is vascularized by the Adamkiewicz arteria which irrigates the anterior spinal arteria. Occlusion or section of the Adamkiewicz arteria may induce an ischemia of the medulla during anterior or transforaminal spine surgery. An angiography allows to determine the exact topography of this artery. The purpose of this study was to describe its preoperative topography and to analyze the impact of angiography on the surgical strategy.

Methods: In this retrospective study, 100 preoperative medullar angiographies, performed by a vascular radiologist between january 1998 and august 2007, were reviewed. Surgical indications were: 50 vertebrectomies in tumors, 20 anterior fusions in dorsolumbar fractures, 10 anterior fusions in malunions, 10 anterior releases in scoliosis, 3 transpedicular osteotomies, 7 disc hernias (T7-L4). The level and the side of foraminal entrance of the Adamkiewicz arteria and collateral arterias irrigating the anterior spinal arteria were analyzed. We looked for the occurence of postoperative ischemic signs of the medulla. Modifications of surgical planning because of Adamkiewicz’ arteria topography were noted. The possibilities of preoperative tumor embolisation were analyzed.

Results: The Adamkiewicz arteria was always localized between T8 and L3. It was present at the foraminal levels L1/L2 or L2/L3 in 48% of the cases. The left side was concerned in 65% of the cases. A modification of the surgical strategy was noted in 16% of the cases: 12 side changements of operative approach, 4 contra-indications for anterior surgery. An ischemic syndrome of the anterior lumbosacral medulla were not found. In the group of tumors, the preoperative angiography allowed to perform a selective embolisation of tumor vessels in 80% of the cases. In all other cases, the tumor vascularisation was common with the vascularisation of the medulla which could have made the embolisation dangerous.

Conclusion: Although the occurence of a lumbosacral medullar ischemia secondary to an Adamkiewicz arteria lesion is rarely reported in the literature, the preoperative angiography reduces this potential risk. The exact knowledge of the anterior medullar vascularisation allows to better plan the surgical strategy and to adapt the side of operative approach. Furthermore, the angiography enables to perform a selective embolisation of tumors safely.

Scoliosis requires three dimensional correction at a global level (curve correction) and at a local one (apical axial derotation) as well as sagittal balance management. Except for in situ contouring, previously reported surgical techniques for scoliosis correction hardly deal with all these issues. The aim of the current study was to evaluate long term clinical and radiological outcomes after in situ contouring in 85 patients with severe scoliosis (Cobb= 40 to 110°). Age influence (adults versus adolescents) and surgical approaches (anterior release and posterior correction and fusion versus posterior correction and fusion only) were also assessed. The results of the study show that the in situ contouring is comparable to other surgical techniques in terms of surgery duration and blood loss. Anterior release proved useful in severe scoliosis correction. No difference in peroperative complications was found between age groups nor between approach groups. However, adolescents recover faster than adults. No difference of revision rates in double approach versus posterior approach populations was found. No statistically significant differences were found between the adolescent and adult populations. The mean overall frontal correction reached 68%. The mean loss of correction amounted 5%. No significant evolution was found in sagittal curvatures, emphasizing the difficulties in restoring physiological curvatures in patients with severe scoliosis. Our results suggest the in situ contouring technique is fully appropriate for severe scoliosis correction, regardless of the patient’s age and approach. Besides it will not result in higher morbidity for one specific population and warrants similar outcome when properly applied.

Introduction: Surgical treatment of thoracolumbar spine fractures from T11 to L2 with correction of the traumatic kyphosis should be expected to avoid the deceptions observed with former treatments.

Material and methods: Seventy trauma victims (41 men and 29 women) underwent surgery between 1996 and 2003. According to the Denis classification, they presented: 16 compressions, 43 burst fractures, 8 seat belt fractures, and 3 disclocations. The Frankel classification was E:62, A:2, C2, D:2. Mean follow-up was 30.7 months. A pedicle screw protected with sublaminal hooks below and pediculotransverse claws above was used in 50 patients with a hybrid configuration in 20. Reduction was achieved by in situ cerclage. A secondary anterior graft was implanted for 38 patients.

Results: Patients were allowed to rise without contention on day 3. The traumatic angle measured with the sagittal index of Farcy (SIF) (the quality parameter used to study reduction) was 17 preoperatively and 1.6 after surgery. The loss at last follow-up was −2.2° with 81% of patients presenting normal or over correction. The loss was greatest (5.2°) for uniquely posterior approaches. The final Oswestry score was 29.8 (range 6–80) with a better result for the double approaches (20.7 versus 37.4, p< 0.001). Complications were phlebitis (n=1), sutured dural breaches (n=2), disassembly and nonunion (revision with a double approach) (n=1), infection (treated by wash-out and antibiotics) (n=10), retroperitoneal hematoma (treated by embolization) (n=1). Thirty-two patients resumed their work at seven months on average and 13 did not (25 without professional occupation).

Discussion: The overall results are better than those after orthopedic treatment. The rate of resumed work was 71%. This is an excellent result with a less aggressive treatment protocol (no corset) and shorter hospital stay (5–19 days). The protective hooks facilitate in situ cerclage, avoiding catching the screws and the risk of disassembly. The anterior graft is necessary when the reduction is discal and reduces the angle loss leading to less morbidity.

Conclusion: In situ cerclage enables constant sustained reduction of thoracolumbar fractures. Indication for surgery is often retained because of major deformation. Spinal fractures should be examined with the same assessment criteria as used for fractures of long bones and weight bearing should begin early to avoid the risks associated with prolonged bed rest.

Purpose of the study: The theoretical usefulness of a disc prosthesis in comparison with arthrodesis would be to restore physiological segmental motion without perturbing the kinematics of the adjacent levels. The purpose of this study was to determine the rotation centers of the lumbar segments before and after implantation of a disc prosthesis with a mobile insert (Mobidisc™).

Material and methods: Lateral flexion and extension views in the sitting position with a stabilized pelvis were obtained before and after implantation of the lumbar disc prosthesis in 32 patients. Spineview™ was applied to the digitalized images for semi-automatic recognition of the vertebral body contours and calculation of the rotation centers. The detection threshold for this automatic system was 5° motion.

Results: Rotation centers were difficult to determine preoperatively because of the absence of mobility. A pathological position was found for three patients. Postoperatively, at three and twelve months, the position was «physiological» in 13 patients, in the posterior half of the disc or inferior body near the vertebral end plate. IN 14 patients, the center could not be determined because motion measured 5° or less. For three patients, the center was too anterior on a prosthesis implanted to anteriorly. There were no changes in the rotation centers for the adjacent levels.

Discussion: Demonstration of an abnormal rotation center could be an additional indication of presumed instability. In certain cases, a disc prosthesis appears to restore the physiological rotation center. But the position and the thickness of the implant can influence their localization.

Conclusion: Restoration of a physiological rotation center for the instrumented intervertebral segment and the absence of change in the rotation centers for the adjacent centers are arguments in favor of disc prosthesis for reducing the incidence of osteoarthritic degradation of adjacent discs in comparison with fusion, under the condition that the implantation and the size are correctly adapted.

Purpose: Scoliosis is a three-dimensional deformation of the spinal column. Modern surgical techniques have attempted to address this 3D component of the problem but pre- and postoperative measurements lack precision. A solution is stereoradiographic 3D reconstruction providing 1.1 mm precision for vertebral shape and 1.4° precision for axial rotation.

Material and methods: Ten patients (seven adolescents and three adults) with idiopathic scoliosis (mean 56°, range 36°–78°) were treated with an in situ arching method. A calibrated teleradiogram (AP and lateral view) was obtained before and after surgery. The spinal columns were reconstructed by stereoradiography. Six rotation angles were measured in the three planes for each vertebra and each intervertebral space, taking into account the curvatures and their apical and junctional zones.

Results: Preoperatively, for thoracic scoliosis, measurements were: mean vertebral axial rotation (VAR) measured at the apex = 20°; mean lateral axial rotation (LAR) of the junctional zones = 30°; mean intervertebral rotation (IVR) = 10°. Depending on the curvatures, in situ arching yielded a 52–60% correction of the VAR at the apex, and 78–79% correction of the junctional zones. VLR of the junctional zoenes was improved 58–74%. Intervertebral sagittal rotation (ISR) at the summit (kyphosis) was improved 5.5° on the average.

Discussion: Unlike computed tomoraphy where scans are obtained in the supine position, three-dimensional reconstruction of the spinal column enables a precise analysis of the loaded spine. Improvement was significant in the frontal plane with 18.3° and 21.4° improvement of the VLR for the thoracic and thoracolumbar junctional zones respectively, compared with the rod rotation where the peroperative stereophotogram showed a 9.6° and 8.6° gain respectively. There was a real improvement in VAR, differing from the literature where the rotation of the rod appears to be less pronounced.

Conclusion: Three-dimensional reconstruction of the spinal column enables a segmentary analysis of scoliosis deformations. In addition, by enabling a view of the spinal column in all directions, angle measurements can be made with precision allowing repeated measurements and comparisons. This technique demonstrated the efficacy of in situ arching in improving vertebral rotation.

Purpose of the study: Surgery for lumbar canal stenosis is classically an intracanalar procedure with the risk of injury of the dura mater or nerve roots or of postoperative haematoma with secondary sequelae. Extracanalar surgery could be useful for the treatment of lumbar canal stenosis in older patients.

Material and methods: The Farcy procedure is based on the observation that the root is compressed in the recessus by the tip of the upper facet. The foramen is too small. The tip can be cut with a chisel along a horizontal line plumb with the pedicle landmark on the upper border of the lateral mass. The tip of the facet and its osteophyte can be removed laterally to medially with a curette and separated from the capsule and the yellow ligament without exposing the root. Release of the foramen is verified with an elevator. From August 1999 to July 2000, 15 patients (ten women and five men) underwent the Farcy procedure in association with fusion-osteosynthesis. Mean age was 60.4 years (55–71). The patients had suffered a mean 8.5 years (1–30). All had lumbalgia. Radiculalgia involved one root in seven patients, two in four and three in four. The Beaujon score was 6.73 (0–14) before surgery. The procedure was performed at one level in five patients, at two in four, at three in four and at four in two. Laminectomy was associated in two patients early in our experience.

Results: Postoperative Beaujon score was 15.2 (9–12) with cure of lumbalgia in eleven patients and cure of radiculalgia in ten patients. five patients had a 100% relative gain and only four had a gain of less than 50%. There were two failures explained by a history of stroke in two women (67 and 71 years). The only complications were one haematoma that was reoperated and one superficial infection.

Discussion: These results are comparable with those obtained with intracanalar surgery. The procedure is equally effective and is more rapid without the risk of the classical complications. The one extradural haematoma observed was related to laminectomy which later was noted to be unnecessary.

Conclusion: The Farcy procedure is a useful technique for the treatment of lumbar spine stenosis. Further experience is needed to determine whether this extracanalar technique should replace classical techniques with the risk of complications related to exposure of the canal.