Introduction

In daily clinical practice, progression of spinal fusion is typically monitored during clinical follow-up using conventional radiography and Computed Tomography scans. However, recent research has demonstrated the potential of implant load monitoring to assess posterolateral spinal fusion in an in-vivo sheep model. The question arises to whether such a strain sensing system could be used to monitor bone fusion following lumbar interbody fusion surgery, where the intervertebral space is supported by a cage. Therefore, the aim of this study was to test human cadaveric lumbar spines in two states: after a transforaminal lumbar interbody fusion (TLIF) procedure combined with a pedicle-screw-rod-construct (PSR) and subsequently after simulating bone fusion. The study hypothesized that the load on the posterior instrumentation decreases as the segment stiffens due to simulated fusion.

Background: Long-term results after fusion for cervical disc disease show evidence of adjacent segment disease, mainly in young and active population. This led to the development of new techniques, i.e. cervical mobile prostheses. 8yr-follow-up of Cervidisc^® semi-constrained prosthesis documented motion preservation, but its design required minor adjustments to assess optimal outcome leading to an optimized version – Discocerv^® Cervidisc Evolution.

Purpose: To evaluate the intermediate outcome in patients operated with Discocerv^®.

Study design: Multicenter prospective non comparative study.

Patient sample: Since April 2006, 77 consecutive patients (41m/36w: mean age 45.2[27–65]) were enrolled in the study so far in 7 centers in France and Switzerland. Mean follow up was 6(0–12) months.

Outcome measures: Clinical evaluation criteria: VAS 1 to 100mm self-reported cervical and radicular pain, NDI (1–50 scale), symptoms evolution (ODOM score), work status, patient satisfaction were recorded pre–and post-operatively. Radiographic criteria: operated levels’ flexion-extension mobility.

Methods: Patients underwent one (C3C4 n=2, C4C5 n= 7, C5C6 n=37, C6C7 n= 28) or multiple level (C5C6/ C6C7 n=2; C4C5/C5C6/C6C7 n=1) cervical arthroplasty with Discocerv for degenerative disc diseases (disc hernia, stenosis, discopathy).

Results: Per-operative complications occurred in 4 patients (5%) without further consequences. No post operative complications were reported. 67% of active patients resumed their previous work within the first 6 months after surgery. The ODOM score showed 100% excellent and good results at 6 to 12mths follow-up.

Mean cervical and radicular VAS-reported pain decreased from 60 [4–84] and 65 [2–96] pre-operatively to 21[0–45] and 21[0–36] at 0–6 months and to 15 [0–40] and 16 [0–40] respectively at 6–12 months. Similarly mean NDI decreased from 25 [9–45] to 10 [0–35] at 0–6 months and to 6[0–36] at 6–12mths. All patients were satisfied with the results so far.

Quantitative radiographic analysis showed satisfactory restoration of cervical mobility at the operated levels with mean flexion-extension mobility 6.4°[1–11°] at 0–3mths and 7.1°[4–12°] at 6–12mths respectively. The adjacent level mobility was found within normal ranges at 6–12mths post-operatively. At the same follow-up period, the regional lordosis was within physiological ranges for 65% of patients at the last follow-up.

Discusssion and conclusion: Our results with Discocerv^® Cervidisc Evolution prosthesis confirm the long term 96% mobility obtained at 7 years follow-up with the first generation of the device, i.e. Cervidisc^®.

Both clinical and radiological findings in this study support the effectiveness of the Discocerv^® Cervidisc Evolution prosthesis at mid-term. However further follow-up at long term is necessary in order to confirm these findings.

Introduction An international six-centre prospective observational cohort study.

Objective. To assess the feasibility of radical surgical excisional treatment of spinal metastasis

Materials and methods. Patients with histologically confirmed spinal metastasis originating from epithelial primary site mostly treated with instrumented surgery were studied. Surgical strategies were either radical excisional (enbloc and debulking) or palliative decompressive surgery. Outcomes assessed were measures of quality of life including pain, mobility, sphincter and neurological functions.

Results. A total of 223 patients with a mean age of 61 years and equal number of males and females were studied. Breast, renal, lung and prostate accounted for three quarters of tumours and 60% had metastasis that extended beyond one vertebra. Most patients presented with pain (92%), paraparesis (24%) and abnormal urinary sphincter 22% (5% were incontinent). Seventy four percent of patients underwent radical surgery, 92% of all patients had instrumented fixation. 73% of the radical group had improved pain control (63% for palliative group), 72% regained ability to walk (45% for palliative group), 92% maintained a functional neurological function of Frankel E/D (64% for palliative) and 55% had improved sphincter control (21% for palliative group).

Overall of all petients who underwent surgery, 71% had improved pain control, 53% regained mobility, 64% improved by at least one Frankel grade or maintained normal neurology and 39% regained normal urinary sphincter function. While 18% were bed bound preoperatively, only 5% were still in bed postoperatively. Perioperative mortality rate was 5.8% and morbidity was 21%. The median survival for the cohort was 352 days (11.7 months). The radical surgery group had a median survival of 438 days and the palliative group 112 days (P = 0.003).

Conclusion. Surgical treatment of spinal metastatic tumour is feasible with low mortality, an acceptably low morbidity and affords patients better quality of remaining life. Radical surgical excision has better outcome than palliative surgery in pain control and in neurological function rescue including regaining mobility and improvement in sphincter control.

Purpose of the study: The results of arthrodesis are often described in the literature by giving the rate of complications and the rate of fusion, but with little information on how the x-rays were assessed qualitatively. The purpose of this retrospective study was to ascertain how useful quantitative radiographic analysis is in evaluating the results of lumbosacral arthrodesis.

Material and methods:The study population included 53 patients who underwent lumbosacral arthrodesis after lumbar discectomy. Clinical data and scores were noted. Sagittal and flexion-extension x-rays of the lumbar spine were obtained at mean five years follow-up. Films were also collected from a group of asymptomatic patients. The quantitative biomechanical analysis was performed with a dedicated software after image digitalization. Spinal, pelvic and vertebral parameters were compared with standard values. The kinetic behavior of the lumbar spine was assessed by recording the intervertebral mobility (IM), and the localization of the rotation centers. Residual mobility of an instrumented segment was considered absent (solid fusion) for MI = 0–3, low (doubtful fusion) for MI = 3–5), and present (nonunion) for MI > 5. The values obtained were compared with statistical tests.

Results: Values recorded for lordosis and pelvis parameters were normal. At last follow-up, solid fusion was noted for 81% of cases, doubtful fusion for 15% and nonunion for 4%. Estimated fusion was correlated with clinical results (r=0.8) and was in agreement (87%) with the surgeon’s qualitative assessment. The adjacent levels presented decreased mobility in 40% of cases and long-term degradation in 17%. The position of the rotation center was normal in 50%.

Discussion: This preliminary study shows that analysis of the sagittal balance and lumbar kinetics provides quantitative information for outcome assessment. Calculating IM determines the residual mobility of the instrumented zone and enables a qualification of the fusion. AS a complement to IM, identifying the position of the rotation center enables a description of the kinematics of the adjacent levels.

Conclusion: Quantitative analysis enables an estimate of 4% for long-term nonunion, with fusion correlated with clinical outcome. Analysis of intervertebral mobility and the position of the rotation center is pertinent for assessment of fusion and the kinematics from lumbar stress x-rays.

Incoming of a spine metastasis remains a major bad prognosis factor in cancer evolution. Consensus over the years is now well accepted in most of European teams dealing with spinal metastasis. Two major opportunities exist in the treatment of spine metastasis:

Conservative treatment with an association of radio and or chemotherapy and or hormonotherapy. Efficiency of such treatments is well documented and must not be considered as a patient abandon.

Surgical treatment is based on two major options. The first one is palliative with the aim of decompression and stabilization. Aim is to cure pain and neurological involvement. The second one is curative with total or partial vertebrectomy in the aim to cure the cancer.

In all cases decision must be made considering age- general condition histo – pathology – neurological status

Considering surgical indications through out this symposium we would like to address three controversial points.

The first topic to be addressed will be: “Total vertebrectomy: when?” presented successively Doctor MARTIN BENLLOCH and Professor BORIANI. The goal of this presentation is to determine the indications of total vertebrectomy more than the surgical technique. These indications appearing essential within the framework of the metastatic patients, while insisting not only on the natural history, but also on the tumoral extension which determines the feasibility of the vertebrectomy. Professor POINTILLART and Professor BORIANI will then discuss about the strategy to adopt when confronted with multi-metastatic patients “Multi-metastatic patients: what strategy?”. This topic will focus primarily on the problem of multi level spinal metastatic lesions: the strategies to be adopted with respect to the patients presenting other metastatic lesions, as well as on a functional forecast (fragility of the long bone), or on the other hand, on metastasis without immediate functional incidence. We also would like to discuss the treatment of the primitive tumour, i.e. if it is the metastasis which is revealing cancer, is it necessary to first treat the primitive tumour, than proceed to the treatment of the metastatic lesions? The third topic of this session will be “When Not to Operate on Metastatic Patients?”, presented by Professor POINTILLART. The goal of this discussion is to be able to give a progress report on the surgical indications within the framework of a spinal metastatic patient. In a certain number of cases surgery is questionable with the discovery of lesions, because of their extended character, or the extreme malignity of the primitive tumour. In other situations, too many lesions will make surgery disputable. Last case scenario is a recurring tumor, because of its extension, its development, even its neurological complications, will make surgery challenging. All these points in our opinion should be openly discussed. Each session will be followed by a 10 minute discussion

Purpose: Postoperative dislocation after revision total hip arthroplasty (rTHA) is a frequent complication. Certain risk factors have been well identified (greater trochanter non-union, history of repeated dislocation or infection, multiple operations), but the role of spinal morphology is not well known. The purpose of this prospective study was to determine the role of spinal morphology on postoperative dislocation.

Material and methods: Between September 2000 and March 2002, 49 patients underwent rTHA. The prospective analysis included a preoperative radiographic evaluation of the spinal morphology for lumbopelvic assessment using the Legave and Duval Beaupère criteria. A standard information card was used pre- intra- and postoperatively to record usual patient- and material-related risk factors of dislocation. Five patients experienced postoperative dislocation despite any apparent defect in implant position.

Results: Mean sacral slope was significantly different (p=0.006) between patients with and without dislocation. This difference remained significant (p=0.017) when limiting the study to the 33 patients who had no associated risk factor postoperatively (history of recurrent dislocation or infection, multiple operations, tight non-union of the greater trochanter).

Discussion: Our study demonstrated the role of lumbar morphology on the risk of postoperative dislocation. Spinal morphology modifies the pelvic orientation and thus landmarks habitually used for implantation. It also affects the amplitude of pelvic movement when moving from the sitting to standing position, requiring hip compensation, particularly extension.

Purpose: The Exeter technique opens new perspectives for the treatment of femoral bone loss observed at revision hip arthroplasty. Early migration of the implant, considered by the advocates of the technique to be beneficial when limited, can, in the absence of secondary instability, weaken the cement shield leading to early revision. Several publications on this topic have examined the improvement in primary stability achieved by modifying the impaction technique or by searching for the ideal size of the grafts. The purpose of the present study was to examine the reproducibility of this method and its effect on transformation of the allograft.

Material and methods: We performed a prospective analysis of outcome in 46 patients operated on since 1996. The Poste-Merle-d’Aubigné (PMA) clinical score and the Ling and Gie radiographic score as well as the SOFCOT score for substance loss were determined. We used frozen fragmented allografts without consideration of graft size. A standard sized femoral implant was used in all cases.

Results: Mean follow-up was 3 years (range 12 – 66 months). Four patients were not followed beyond 9 months because of major complications requiring revision surgery (infection, fracture of the femur, malposition) or patient death (stroke). For the remaining 42 patients, loss of femoral stock was scored I in 6, II in 23, III in 13. The functional score improved from 9.13±3.9 preoperatively to 16.07±2.5 postoperatively. Radiographically, bone lines were observed in the graft in 36 patients, associated with bone remodelling in ten. In six patients, the allograft exhibited a heterogeneous aspect. Three implants migrated 4 mm. Defective distal sealing was noted in all three. One prosthesis implanted in a varus position worsened before stabilising.

Discussion: This technique is a reliable method since primary stability of the implant was obtained in 90% of the cases and was maintained during long follow-up. This did not prevent graft remodelling.

Purpose: Several techniques have been proposed for C1-C2 fusion. The anterior transoral technique is the most direct approach but at the cost of major risk of infection. The posterior approach allows wiring (Gallie technique) or direct atloidoaxoid screw fixation (Magerl technique). The retrosternomastoid bilateral approach (Du Toit technique) allows direct screwing in the lateral masses. The rate of nonunion reported in the literature is high for wiring techniques. Biomechanical studies have demonstrated the mechanical superiority of trans-articular screwing which has been confirmed in clinical series. The purpose of the present study was to describe a modification of the Du Toit technique and describe results in a short series.

Material and methods: This modification of the Du Toit technique consists in an abrasion of the C1 lateral mass at its origin enabling the penetration of a Cloward curette to create a stable introduction point for the drill bit and thus avoid slippage forward as can occur with the conventional technique. The screw is directed towards C2, in a strict frontal plane. The obliquity depends on the room allowed by the mastoid. The drill bit should cross both corticals of the inferior facet of C1 and the superior facet of C2. The screws must cross in a coronal plane just under the odontoid. Fusion of the C1-C2 lateral masses is achieved by abrasion and grafting.

We have used the modified Du Toit technique for C1-C2 arthodesis in four patients with rheumatoid arthritis, fracture of the odontoid, an odontoid bone, and isolated degeneration. The procedure was a first intention treatment for the patient with primary degeneration, and a second intention procedure for the others who had developed nonunion after wiring.

Results: Mean hospitalisation was six day. Operative time was 2 h 10 min. Mean blood loss was 200 ml peroperatively and 120 ml postoperatively. None of the patients had developed nonunion or mechanical failure at a mean follow-up of 2.7 years (range 1 – 5 years). Operative complications included one case of venous bleeding which was treated with vascular clips and two cases were the lateral mass of C1 was weakened requiring cementing. There was one early postoperative neurological complication with hypoaesthesia of the hemitongue that regressed spontaneously. None of these complications produced sequelae.

Conclusion: The advantages of the modified technique for lateral screw fixation of C1-C2 is the improvement in the entry point for the drill bit allowing an optimal screw position and a stable drilling to achieve good mechanical fixation and certain union.

Purpose: Tumours arising from the pulmonary apex or the posterior mediastinum may be removed en bloc in combination with total or partial vertebrectomy in the event of spinal invasion. Extra-tumour resection is a perfectly described surgical procedure recognised for its carcinological effectiveness. Raymond Roy-Camille and Bertill Steiner described en bloc spinal resection of a thoracic vertebra via a simple posterior approach. Paulson, described resection of tumours of the pulmonary apex (Pancoast Tobias) via a cervicothoracic approach. We associated these two techniques to allow en bloc resection of posterior mediastinal tumors or pulmonary apex tumours associated with spinal invasion.

Material and methods: We recommend different surgical approaches to the cervicothoracic and mid thoracic spine. For the cervicothoracic spine, an anterior approach is used with simple dislocation of the sterno-clavian joint without resection of the clavicle. The subclavian vessels and the brachial plexus are dissected and exposed. The tumour is then dissected followed by the peripheral, particularly œsophageal, attachments. The tumour is not detached from the spine to which it adheres tightly. Conventional thoracotomy is used for the thoracic level with dissection of the tumour from the adjacent soft tissue. In the event of a tumour in the posterior mediastinum, the anterior time is followed by a posterior approach. For primary pulmonary tumours, lobectomy or segmentectomy, or even pneumonectomy, is performed during the anterior time. Total or partial vertebrectomy, depending on the level of spinal involvement, is performed during the posterior approach.

Results: Thirty-six patients underwent this type of procedure. Total vertebrectomy was necessary in seven patients, partial vertebrectomy in 29. Mean follow-up has been six days to 7.2 years (mean 23.3). One patient died during the postoperative period due to a cause unrelated to the tumour. Only 35 patients were retained for analysis. Twenty-one patients (60%) died after a mean survival of 16.7 months (8–44 months). The 14 others (40%) are living at a mean 38.2 months survival (8–87 months).

Discussion: This technique requires a long learning curve and an extremely careful evaluation of tumour extension. Results obtained to date confirm the feasibility of the technique and point out its contribution in case of wide resection. Certain patients have lived more than five years after resection.

Purpose: We analysed retrospectively 32 cases of posterior cervicothoracic fixation for spinal tumours. We evaluated spinal stability, spinal alignment, and associated complications.

Material and methods: Thirty-two patients underwent surgery: 27 men and five women, mean age 52 years, age range 17–72 years. We implanted 96 articular screws in C4 to C6, 54 screws in C7 and 180 pedicular screws in T1 to T8. Nineteen patients had primary lung cancer with spinal invasion, eleven had spinal metastases, one had a chondrosarcoma and one had a myeloma. For the first group of 19 patients, en bloc resection of the tumour with the vertebra was performed: four total vertebrectomies, 15 partial vertebrectomies. In a second group of 15 patients, palliative posterior fixation was performed with laminectomy decompression.

Results: Follow-up ranged from three to 54 months with a mean of 15 months. Mean survival after total or partial vertebrectomy was 16 months (range 3 – 54 months). Survival after palliative decompression was eleven months with a range from five to 19 months. There were no changes in the sagittal alignment in 30 patients: two patients developed mechanical complications late after surgery requiring revision. We did not have any case of screw, plate or rod fracture. There were no neurological complications related to screw insertion either at the thoracic level (180 screws) or the cervical level (96 screws in C4C5C6 and 54 screws in C7). A control scan was available for 21 patients and revealed a malposition of the implanted screws for 2.5% of the screws with no clinical impact.

Discussion: Posterior screw fixation is a good method to stabilise the cervicothoracic spine during tumour surgery. Articular cervical screws and transpedicular thoracic screws provide effective stability postoperatively. In addition, this type of instrumentation does not interfere should subsequent laminectomy or wider resection be necessary.