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C Mazel

Publications and source records attributed to C Mazel.

At least 19 recordsLinked to original sources
PubMed2006

[Vertebral en bloc resection for lung cancer: twelve years' experience].

OBJECTIVES: To report a single-institution retrospective study of radical en bloc resection for lung cancer invading the spine. METHODS: Between 1993 and 2004, 32 patients underwent partial or total vertebrectomy for non-small cells lung cancer with spinal extension. Twenty-one received induction treatment (chemotherapy, N=16; radiation, N=1 and chemoradiotherapy, N=4). Pneumonectomy was performed in 3 patients, lobectomy in 26 patients and wedge resection in 3 patients. Partial vertebrectomy was performed in 26 patients and total vertebrectomy was performed in 6 patients. Tumor stage was IIb in 9 patients, IIIa in 2 patients and IIIb in 21 patients. RESULTS: There was no immediate postoperative mortality. Major morbidity was observed in 10 patients (31%), including 4 complications related to spinal surgery. For 28 patients, a completed resection was achieved (87%). 2-years survival was 65% and 5-years survival was 24%. Completed resection and induction chemotherapy appear to be determinant prognostics factors (respectively p=0,01 and p=0,04 in univariate analysis). CONCLUSION: Radical en bloc resection with vertebrectomy for lung cancer is technically demanding. Encouraging long-term survival suggest that this surgical approach could be a valid option for selected patients with vertebral involvement of lung cancer.

Adult↗
PubMed2005

Validation of new clinical quantitative analysis software applicable in spine orthopaedic studies.

The objective of this study was to evaluate an X-ray films analysis software, i.e. to estimate the reliability and validity of clinical measurements by means of this software. The authors first performed tests of precision and reproducibility of measures. The precision for dynamic modules was estimated at +/-2 degrees for the lumbar analysis and +/-3 degrees for the cervical one. Mean reproducibility coefficients calculated for postural modules are about 4 degrees for the angular parameters and 3 mm for the linear ones. We also evaluated clinical applicability of the software through its validity. Reference values calculated on a population of healthy subjects showed agreement with the literature. Then, when analysing postural X-ray films of severe scoliotic patients, we found that inter-observer reproducibility coefficients show a lower reliability of measurements; the main cause seems to be the low visibility of anatomic landmarks due to the quality of X-ray films and to the degree of deformity. This study allowed to better estimate the reliability and the usefulness of this tool, allowing for multicentric studies and exchanges.

Cervical Vertebrae↗
PubMed2005

[Impaction posterior wedge osteotomy for the treatment of postsurgical flatback: 22 cases].

PURPOSE OF THE STUDY: There is increasing interest in sagittal balance as an important element when planning treatment of spinal deformations. Posture disorders, particularly flatback, can be observed after surgical treatment of scoliosis. The frequency of flat back syndrome has increased with the development of spinal surgery. MATERIAL AND METHODS: Posterior osteotomy is designed to resolve these problems. Two techniques are used: the Smith-Petersen procedure and transpedicular subtraction osteotomy. We adopted the second procedure, adding two technical modifications: installation on an orthopaedic table and intracorporeal cancellous impaction. We performed closed posterior osteotomy by intracorporeal impaction and report here our results in a series of 22 patients with postoperative flat back treated between July 1999 and June 2002. Mean age at surgery was 52 years. There were sixteen women and six men. All patients had a history of spinal surgery with fusion. They had had 2.1 spinal operations on average with a maximum of seven. All patients complained of severe postural pain. They had difficulty bending forward and standing back up. Radiographically, we noted altered spinal and pelvic angles and an abnormal plumb line from C7 to the promontory. RESULTS: We analyzed outcome at 21 months on average. Preoperatively five patients had 12 levels of non-union. Osteotomy was performed at L4 in nineteen patients and L3 in three. A rigid instrumentation was used in all cases. Osteosynthesis material was implanted after correction of the deformation with no particular problem for spinal stability or reduction. Mean operative time was 180 minutes and mean blood loss was 1680 ml. A complementary anterior approach was required in one patient. Intraoperative complications were dominated by dural breaches in five patients, high paraplegia not directly related to the osteotomy in one patient, regressive S1 paresia occurred in one patient and transient cruralgia which regressed in 4 to 6 months in four patients. We also observed functional intestinal obstruction in one patient and severe depression in another. There were no infections or deaths. We also observed two cases of predominant correction at the discal level and not the vertebral level. All operated patients felt their posture was improved and were able to maintain the upright position for prolonged periods. Flexion of the lower limbs was improved. Mean correction of lumbar lordosis was 25.1 degrees (range 12-39). Mean sacral slope was 33 degrees . Mean correction of the position of C7 on the promontory plumb line was 72 mm. This variable was highly altered preoperatively (95.6 mm) and was improved after osteotomy in all patients. At last follow-up, there was one case of nonunion which had been successfully revised. DISCUSSION: The literature on osteotomy for the treatment of flat back is sparse. Our series of subtraction osteotomy is the largest reported to date. Preoperative and intraoperative planning remain a topic of debate and require further study.

Adult↗
PubMed2004

Thoracoscopic removal of neurogenic mediastinal tumors: technical aspects.

BACKGROUND: Thoracoscopy is fast becoming the standard approach for the removal of neurogenic mediastinal tumors. However, there are risks for adjacent nervous structures (stellate ganglion, spinal cord). The aim of this study was to review the technical features of this approach. METHODS: Between December 1999 and January 2003, nine patients underwent thoracoscopic resection of a mediastinal neurogenic tumor at our hospital. Five of these patients were asymptomatic with incidentally found tumor; the other four patients had compression-related syndromes. Two tumors had developed in the superior sulcus, and one had a spinal canal component (dumbell-type tumor). RESULTS: Thoracoscopic dissection was possible in all cases. In one patient, resection of the tumor was performed via a combined neurosurgical and thoracoscopic approach. Seven tumors were benign nerve sheath tumors (schwannoma), and 2 were nerve cell tumors (ganglioneuroma). The postoperative course was uncomplicated in all patients. CONCLUSION: The thoracoscopic resection of mediastinal neurogenic tumors is technically easy, except for bulky tumors of the superior sulcus and dumbbell tumors, which require a combined thoracoscopic and neurosurgical approach.

Adolescent↗
PubMed2004

[Role of sagittal spinal curvature in early dislocation after revision total hip arthroplasty: prospective analysis of 49 revision procedures].

PURPOSE OF THE STUDY: Hip dislocation after revision total hip arthroplasty (RTHA) is a frequent post-operative complication. Certain risk factors are well identified (nonunion of the greater trochanter, history of recurrent dislocation or infection, multiple procedures), the role of spine morphological remains to be fully examined. The purpose of this prospective analysis was to assess the role of spine morphology in post-operative dislocations. MATERIAL AND METHODS: Forty-nine patients who underwent RTHA between September 2002 and March 2002 were evaluated prospectively. A complete pre- and postoperative spinal work-up was available for all patients to evaluate the lumbopelvic static using the Legaye and Duval Beaupère morphology criteria and the pelvic-femoral angle to assess hip joint extension. Pre-, per- and post-operative data including the usual risk factors for dislocation related to the clinical situation and the technique used were recorded on a digital datasheet. Five patients developed postoperative dislocation despite the absence of defective implant position. There was no relation with access (p=0.832) or pelvic-femoral angle (p=0.515). RESULTS: The mean value of the sacral slope was significantly different (p=0.006) in patients who developed dislocation in comparison with the other patients. This difference remained significant (p=0.017) for the cohort of 33 patients who had no associated risk factor for postoperative dislocation (history of recurrent dislocation or infection, multiple procedures, tight nonunion of the greater trochanter). DISCUSSION: Our results suggest that the morphology of the lumbar spine can be involved in the risk of postoperative dislocation. The morphology of the lumbar spine affects the pelvic static and thus the landmarks usually used for implantation, but it can also limit the amplitude of pelvic movement when changing from the sitting to the standing position, which would be compensated for by greater hip movement, particularly extension. The method we used did not fully take into account the consequences of changes in spinal balance due to thoracic deformations nor to analgesic (or not) hip flexion and subsequent deformation of the lumbar spine.

Hip Dislocation↗
PubMed2003

[Contribution of the Gigli saw for ablation of non-loosened surface-treated femoral stems inserted without cement: six cases].

The purpose of this work was to present a technique using the Gigli saw through a transfemoral approach in removal of surface-treated femoral implants without cement. Results from six cases are reported. For five patients, ablation of the implant was achieved easily and rapidly with the Gigli saw, taking a mean nine minutes once the cortical window had been achieved. The technique failed in one patient. We had one fracture of the cortical window at its removal and one transverse shaft fracture in the lower part of the femorotomy related to movements of the Gigli saw. A standard length stem was implanted in four of the five successful cases. Complete weight bearing was authorized between the 3(rd) and 7(th) month. Bony healing of the cortical window was achieved in 4 out of 5 cases before the end of the first year.

Arthroplasty, Replacement, Hip↗
PubMed2002

[Value of preoperative planning in total hip arthroplasty].

PURPOSE OF THE STUDY: Preoperative planning enables an assessment of the size of the implants needed before total hip replacement. Eggli and Müller demonstrated the reproduciblity of preoperative planning but did not evaluate its contribution to reducing limb length discrepancy. As femur lateralization and the position of the prosthetic center of rotation affect joint mechanics, it would be useful to assess their contribution to the efficacy of preoperative planning. PATIENTS AND METHODS: We reviewed the files of 57 patients who underwent total hip arthroplasty for primary joint degeneration or necrosis limited to one hip. The healthy hip served as a control. The surgical plan was elaborated from the preoperative pelvis x-rays (AP and lateral views) and anatomic measurements on films obtained three months postoperatively. RESULTS: In 49 cases, preoperative planning predicted a restoration of the normal anatomy of the operated hip (center of rotation, femur lateralization, length of the operated limb). This objective was achieved in only 22.5% of the cases. Femur lateralization was the most difficult objective to achieve (59.2%). Equal limb length and good position of the center of rotation was achieved in 70% of the cases. For eight patients (14%) preoperative planning was not satisfactory, the implant offset not being adapted to the patient's anatomy. DISCUSSION: There are limits to preoperative planning, particularly for restitution of adequate femur lateralization. This difficulty appears to be related to three factors: inadequate adaptation of the implant to hip anatomy (14% of the cases in our experience), stiff rotation in degenerative hips inhibiting proper assessment of the length of the femoral neck, and relative imprecision of operative evaluation of femoral anteversion affecting femur lateralization and the level of the femoral cut. CONCLUSION: Although imperfect, preoperative planning is, in our opinion, essential before total hip arthroplasty in order to avoid major positioning errors and operative difficulties.

Arthroplasty, Replacement, Hip↗
PubMed2002

[Systematic circumferential (360 degree) decompression treatment of major arthrotic cervical stenosis].

PURPOSE OF THE STUDY: Worsening and irreducible evolution of neural involvement in cervical stenosis requires cord decompression. Different techniques have been proposed. We associated a dual posterior then anterior approach to achieve 360 degrees decompression. We evaluated results on the basis of neurological and mechanical outcome. MATERIAL AND METHODS: Twenty-eight patients, 16 men and 12 women, mean age 60.2 years (range 40-82) underwent surgery between 1989 and 1999 for severe cervical canal stenosis. Patients were referred for neurological symptoms: 20 for radicular symptoms (8 pain, 11 motor deficit, 12 sensitive deficit). Fifteen patients presented myelopathic symptoms. Pyramidal syndrome in 11 and tetraparesia in 3. Neurological involvement was scored according to Nurick (average 1.74) and JOA (average 12.6). Pain was scored on the Robinson scale. Levels to decompress were identified on static and dynamic plain x-rays, CT scans and MRI. Myelography was rarely used (first case only). MRI demonstrated preoperative myelomalacia in 5 patients and syringomyelia in 2. The surgical technique for 360 degrees fusion involved two steps, performed with a 1-week interval for 12 patients and during the same procedure for the others. The first approach was posterior enabling spine fixation with bilateral Roy-Camille plates and decompression by laminectomy using the lobster shell technique. The anterior approach consisted in corpectomy with the Simmons technique (22 cases or multilevel interbody fusion according to Robinson. Iliac bone grafting was used in all but one patient who had a fibular bone graft. Mean follow-up was 18.5 months (6-78). RESULTS: Neurological improvement was 1.74 to 0.92 on the Nurick sclae and from 12.6 to 15.2 on the JOA scale at last follow-up. Fusion was obtained in all cases. There were 2 cases of neurological worsening and one transient dysphagia. Operative bleeding for the two steps was 700 ml (150 ml for the posterior procedure and 400 ml for the anterior procedure). CONCLUSION: 360 degrees arthrodesis for severe cervical canal stenosis provides a satisfactory solution to mechanical problems and substantial neurological improvement. Fusion is regularly obtained without complementary anterior instrumentation. Neurological improvement is correlated with disease duration and the degree of deficit at onset. Anteroposterior decompression and 360 degrees fusion provide cure for all the components of stenotic disease. The dual approach is indicated in severe cases with cord involvement as recognized by myleopathic clinical manifestations and on the MRI.

Adult↗
PubMed2001

A simple technique to remove well-fixed, all-polyethylene cemented acetabular component in revision hip arthroplasty.

Well-fixed, all-polyethylene acetabular components may have to be removed in cases of recurrent dislocations, infection, or fracture of ceramic femoral heads. We describe a simple technique using acetabular reamers that allow cup thinning. Through this technique, the polyethylene rigidity is diminished considerably, allowing its easy removal without any risk of fracture, particularly of the acetabulum walls.

Arthroplasty, Replacement, Hip↗
PubMed2001

[Perioperative complications after total hip revision surgery and their predictive factors. A series of 181 consecutive procedures].

PURPOSE OF THE STUDY: We conducted a retrospective study to assess morbidity and mortality in patients undergoing revision total hip arthroplasty (THA) procedures. MATERIAL AND METHODS: Perioperative complications were recorded in 181 revision procedures (162 patients) performed between January 1995 and March 1999 (117 bipolar revisions and 64 acetabular isolated revisions). RESULTS: There were 86 complications (68 patients) leading to 21 new revisions. About half (50/86) were related to the surgical procedure (dislocation, femoral fracture, infection.). Life-threatening complications (3.6%) ended in patient death in 1.6% of the cases. Complications were more frequent in patients with an ASA score=3 (p<0.01) or aged over 75 years (p<0.05). Age was also predictive of femoral misalignment and fracture (p<0.05). Dislocations (8.8%) were observed more frequently in patients who had undergone more than 2 procedures prior to the revision (p<0.05) (4.8% of the dislocations in patients undergoing a first revision procedure and 14.3% in the others). In addition, peroperative blood loss and duration of the procedure were significantly greater in case of bipolar replacement than for isolated acetabular replacement (sigma > 1.96). DISCUSSION: Our experience and data in the literature point to the important age factor in the development of complications. Preservation of a well-fixed femoral component does not appear to worsen prognosis and leads to fewer complications than bipolar changes. CONCLUSION: The decision to revise a THA must take into consideration the functional impairment but also the risks inherent in revision procedures, particularly in old patients who have undergone several procedures. Revising the acetabular component alone can be an interesting option if the femoral component remains well-fixed although our follow-up is insufficient to determine whether this attitude provides better long-term outcome than complete biopolar revision. Better patient selection and improved operative technique, in particular in femur preparation, should help reduce morbidity and mortality in this type of procedure.

Adolescent↗
PubMed2001

[Congenital hypoplasia of lumbosacral articular process: report of a case, review of the literature, and therapeutic proposition].

Congenital hypoplasia of the lumbosacral process is an uncommon cause of recurrent lumbalgia. The 37 cases reported in the literature illustrate the complexity of the pathological implications of these anomalies. We report another case and our diagnostic methodology. We propose lumbosacral arthrodesis which provided complete relief in our patient. This satisfactory outcome has been maintained at one year.

Abnormalities, Multiple↗
PubMed2000

[Detection of asymptomatic venous thrombosis after lower limb prosthetic surgery. Retrospective evaluation of a systematic approach using Doppler ultrasonography: 400 cases].

OBJECTIVES: The purpose of this study was to evaluate a pragmatic approach using duplex ultrasonography (US) for detecting deep vein thrombosis (DVT) after total hip (THA) and total knee (TKA) replacement. METHODS: Venous B-mode and color duplex US examination of both legs including a systematic evaluation of calf veins was performed twice during hospital stay (Between day 1 and day 4 for the first exam and between day 7 and day 11 for the second) in 400 consecutive patients. RESULTS: Deep vein thrombosis was diagnosed in 53 patients (13.5%) including 7 patients with proximal DVT. Thrombosis was asymptomatic in 46 patients (85%), and was bilateral or concerned the non-operated leg in 8 patients (14.5%). No clinical pulmonary embolism (PE) occurred during hospital stay (mean hospital stay: 12.3). Prior phlebitis and age over 70 were identified as a statistically significant risk-factor for post-operative DVT (p = 0.001 and p < 0.01 respectively) concerning the whole series and the THA series (p < 0.02 and p < 0.04 respectively). No statistically significant risk factor was founded for the TKA series (p < 0.2 and p < 0.2 respectively). All patients were seen at three months. Four patients (1.16%) developed DVT between hospital discharge and the 3-month follow-up visit. One patient with coronary disease died suddenly on post-operative day 24, without clinical signs or symptoms of PE or DVT. CONCLUSION: Venous US performed twice after total hip replacement detected asymptomatic DVT in 85% of patients. This approach might explain the absence of PE in our series and thus justify systematic ultrasonographic evaluation of lower limb veins after prosthetic replacement.

Adult↗
PubMed1996

Primary vertebral and spinal epidural non-Hodgkin's lymphoma with spinal cord compression.

We examined eight patients with primary spinal epidural non-Hodgkin's lymphoma presenting with spinal cord compression and proven histologically after laminectomy (7 cases) or biopsy (1 case) by MRI. The most common findings were an isointense or low signal relative to the spinal cord on T1-weighted images (T1WI) and high signal on T2-weighted images (T2WI). Spinal cord compression, vertebral bone marrow and paravertebral extension were assessed. Contrast enhancement was intense in seven of the eight cases and homogeneous in all of them. T2WI (performed in 2 cases) may be useful to distinguish metastatic carcinomas and sarcomas. T1WI demonstrated the full extent of the epidural lesion, which was well-delineated in all cases. When the paravertebral extension is not well-defined, a study with contrast medium should be performed.

Adult↗
PubMed1996

Total vertebrectomy for en bloc resection of lung cancer invading the spine.

We describe a technique of total vertebrectomy for en bloc resection of a non-small cell lung cancer with vertebral invasion through a combination of thoracic and enlarged posterior approaches, and present our entire experience of total and partial vertebrectomy for tumors invading vertebral bodies or the costovertebral angle.

Carcinoma, Non-Small-Cell Lung↗
PubMed1993

[Somatosensory evoked potentials during spinal orthopedic surgery in adult patients].

Somatosensory evoked potentials (SEPs) were recorded in 165 patients from 185 operations for scoliosis and major spinal distortions, lumbar or cervical stenosis, post-traumatic malunions, or tumors. They were obtained by percutaneous stimulation of right and left median and tibial posterior nerves, and recorded on the scalp as recently, motor potentials (MPs) have also been obtained, by a trans-spinous stimulation rostral to the level of intervention. The protocol consists of pre- and post-operative recordings, as well as a continuous intra-operative monitoring. Neuromonitoring is justified in operations implying neurological risks, particularly scoliosis. A durable disappearance of SEPs and MPs was always associated with post-operative neurological disorders. Transient disappearances, not associated with neurological disorders, have been observed during certain manoeuvres such as vertebral traction, osteosynthesis, placing trans-pedicular screws or hooks, leading the surgeon to modify the operation. The role of medullary ischemia on the degradation of electrophysiological signals, obvious in cardiovascular decompensations, seems predominant in the post-operative occurrence of neurological impairment. During the post-operative period, SEPs allow one to discriminate between organic disorders and subjective complaints; they help in diagnosing hematomas, and distinguish between radicular and spinal cord injuries.

Adolescent↗
PubMed1992

Three-dimensional geometrical and mechanical modelling of the lumbar spine.

The main objective of this study is to design a three-dimensional geometrical and mechanical finite element model of the lumbar spine. The model's geometry is constructed using six parameters per vertebra. These parameters are digitized from two X-rays (anterio-posterior and lateral), thus yielding an individualized model which can be arrived at from the radiographs of a tested specimen. This procedure makes the model validation easier, as geometry is generally a factor of dispersion in experimental results. The geometrical reconstruction, in the form of a finite elements mesh, was effected for the whole lumbar spine. The global coherence of the model was verified.

Humans↗
PubMed1992

Management of fracture separations of the articular mass using posterior cervical plating.

Fracture separations of the articular mass are a specific group of unilateral facet fractures that must be considered separately because of their unique two-level instability. This fracture pattern involves a longitudinal fracture of the lamina and a fracture of the pedicle on the same side of the spine at the same level. It is characterized roentgenographically by horizontalization of the lateral mass, with a mean translation of 4.6 mm and a mean angulation of 6.9 degrees. In this study the deformity most commonly occurs at the level below the fracture (19 patients) but also occurred at the level above (5 patients). There is a high incidence of neurologic involvement (14 of 24 patients), most often radicular in nature. This injury results in two level instability requiring a three-level, two-interspace stabilization. All twenty-four patients in this series underwent posterior cervical plating with either an asymmetric (8), symmetric (9) or porte manteau (7) construct. Statistically significantly better results (P < 0.05) were achieved with either a symmetric or porte manteau construct. Complications including neurologic deficit and loss of correction were more frequent in the asymmetric group.

Adult↗