Pierre Coudert

Outcomes of the Bryan cervical disc replacement: fifteen year follow-up

BackgroundThe CTDR is a technique that treats cervical disc degenerative disease. Initial shorter-term studies showed good clinical and radiological results.PurposeTo assess the clinical and radiological results of Bryan cervical disc replacement (Medtronic Sofamor Danek Inc., Memphis, TN) at 15-year follow-up.ResultsThis prospective study included 20 patients who underwent 22 CTDR, comprising a single-level procedure in 14 patients and two-level procedures in six patients. The mean follow-up period was 15.5xa0years. The mean age at the intervention was 46.2xa0years (range: 26–65xa0years). Two patients needed re-operation for recurrence of symptoms. According to Odom’s criteria, 80.0% (16 of 20 patients) had excellent outcomes, VAS for neck pain was 2.6 (0–10), for shoulder/arm pain it was 1.8 (0–7), and NDI at the final follow up was 14.9. The SF-12 PCS was 46.1, and SF-12 MCS was 51.9. Mobility was maintained in 15 of the 22 (68.2%) operated segments, range of motion (ROM) of prostheses were 9°u2009±u20093.9° (range 4–15°). The prostheses were positioned in kyphosis in 14 of 22 levels (63.6%). There was a positive correlation between the kyphosis of the prosthesis and the occurrence of heterotopic ossification (HO), and their grade (ρu2009=u20090.36, CI 95%[−0.68; 0.07]). HO had developed at 12 of the 22 levels (54.5%) and upper adjacent segment degeneration in 11 of 18 of patients (64.7%). All these results were not significantly different to outcomes at 8xa0years follow-up.ConclusionIn a cohort of 20 patients with 15-year clinical and radiological follow-up, the Bryan CTDR has demonstrated a sustained clinical improvement and implant mobility over time, despite a moderate progression of degenerative processes at the prosthetic and adjacent levels.

Is it safe to perform lumbar spine surgery on patients over eighty five

PurposeThe purpose of this study was to evaluate the safety and tolerance of lumbar spine surgery in patients over 85.Materials and methodsPatients over 85 years of age with LSS who underwent decompression surgery with or without fusion between February 2011 and July 2014 were included. Comorbidities, autonomy (Activities of Daily Life and Braden scales), surgical parameters and complications (Clavien-Dindo classification) were collected. A telephone survey was performed to assess survival and patients’ satisfaction at last follow-up.ResultsMean follow-up was 27.4xa0±xa07.6xa0months (range, 18–65). Mean age was 87.5xa0±xa02.7xa0years (range, 85–97). Mean ADLs and Braden scores were, respectively, 4.3xa0±xa01.2 and 20.2xa0±xa01.4. Fifteen patients had associated spondylolisthesis. Nineteen minor complications (grade I and II, 38.7%), five moderate complications (grade III, 10.2%) and six major complications (grade IV and V, 12.2%) occurred. The perioperative mortality rate was 0.02%. At last follow-up, 41 patients were very satisfied (83.7%), five patients were satisfied (10.2%) and three patients were not satisfied (6.1%). Fusion did not affect the incidence of complications (pxa0=xa00.3) nor the average number of complications per patient (pxa0=xa00.2).ConclusionAdvanced age should not be a contraindication to lumbar spine surgery provided careful preoperative selection is performed. This study reported a high satisfaction rate and a low mortality rate at the price of a high number of complications, most of which being minor.

A new classification system for degenerative spondylolisthesis of the lumbar spine

PurposeThere is no consensus for a comprehensive analysis of degenerative spondylolisthesis of the lumbar spine (DSLS). A new classification system for DSLS based on sagittal alignment was proposed. Its clinical relevance was explored.MethodsHealth-related quality-of-life scales (HRQOLs) and clinical parameters were collected: SF-12, ODI, and low back and leg pain visual analog scales (BP-VAS, LP-VAS). Radiographic analysis included Meyerding grading and sagittal parameters: segmental lordosis (SL), L1–S1 lumbar lordosis (LL), T1–T12 thoracic kyphosis (TK), pelvic incidence (PI), pelvic tilt (PT), and sagittal vertical axis (SVA). Patients were classified according to three main types—1A: preserved LL and SL; 1B: preserved LL and reduced SL (≤5°); 2A: PI–LL ≥10° without pelvic compensation (PTxa0<xa025°); 2B: PI–LL ≥10° with pelvic compensation (PTxa0≥xa025°); type 3: global sagittal malalignment (SVA ≥40xa0mm).Results166 patients (119 F: 47 M) suffering from DSLS were included. Mean age was 67.1xa0±xa011xa0years. DSLS demographics were, respectively: type 1A: 73 patients, type 1B: 3, type 2A: 8, type 2B: 22, and type 3: 60. Meyerding grading was: grade 1 (nxa0=xa0124); grade 2 (nxa0=xa024). Affected levels were: L4–L5 (nxa0=xa0121), L3–L4 (nxa0=xa034), L2–L3 (nxa0=xa06), and L5–S1 (nxa0=xa05). Mean sagittal parameter values were: PI: 59.3°xa0±xa011.9°; PT: 24.3°xa0±xa07.6°; SVA: 29.1xa0±xa042.2xa0mm; SL: 18.2°xa0±xa08.1°. DSLS types were correlated with age, ODI and SF-12 PCS (ρxa0=xa00.34, pxa0<xa00.05; ρxa0=xa00.33, pxa0<xa00.05; ρxa0=xa0−0.20, and pxa0=xa00.01, respectively).ConclusionThis classification was consistent with age and HRQOLs and could be a preoperative assessment tool. Its therapeutic impact has yet to be validated.Level of evidence4.

Prospective Comparative Study in Spine Surgery Between O-Arm and Airo Systems: Efficacy and Radiation Exposure

OBJECTIVEnPedicle screw placement remains challenging. The present study focuses on the comparison between 2 intraoperative-based neuronavigation systems (O-Arm and AIRO) during thoracolumbar screw instrumentation.nnnMETHODSnThis is a prospective, comparative, nonrandomized study conducted in 2 French academic centers. The O-Arm was used at the University Hospital of Bordeaux, whereas the AIRO was used at the University Hospital of Marseille. Routine computed tomography was performed on postoperative day 2 to evaluate pedicle screw placement. Measures of radiation exposure were extracted directly from reports provided by each system. The effective dose was calculated.nnnRESULTSnOverall, 74 screws were placed in 11 patients in the O-Arm group and 84 in 11 patients in the AIRO group. In the first group, 90.8% were rated as acceptable and 92.2% in the second (P > 0.05) according to the Heary and Gertzbein classifications, respectively, for thoracic and lumbar spine. Differences between both implantation systems were significant (P < 0.05) concerning dose length product (235 and 1039 mGy/cm, in O-Arm and AIRO, respectively), overall mean radiation dose received by 1 patient (3.52 and 15.6 mSv in O-Arm and AIRO, respectively), mean radiation dose per single scan (2.58 and 8.7 mSv in O-Arm and AIRO, respectively), mean effective dose per instrumented level (1.04 and 3.9 mSv in O-Arm and AIRO, respectively), and radiation dose received by the primary surgeon (0.63 and 0 μSv in O-Arm and AIRO, respectively).nnnCONCLUSIONSnIntraoperative computed tomography-based navigation is a major innovation that improves the accuracy of pedicle screw positioning with acceptable patient radiation exposure and reduced surgical team exposure.

Radiographic Classification for Degenerative Spondylolisthesis of the Lumbar Spine Based on Sagittal Balance: A Reliability Study

STUDY DESIGNnInter- and intraobserver reliability study.nnnOBJECTnTo assess the reliability of a new radiographic classification of degenerative spondylolisthesis of the lumbar spine (DSLS).nnnSUMMARY OF BACKGROUND DATAnDSLS is a common cause of chronic low back and leg pain in adults. To this date, there is no consensus for a comprehensive analysis of DSLS. The reliability of a new DSLS classification system based on sagittal alignment was assessed.nnnMETHODSnNinety-nine patients admitted to our spinal surgery department for surgical treatment of DSLS between January 2012 and December 2015 were included. Three observers measured sagittal alignment parameters with validated software: segmental lordosis (SL), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), and sagittal vertical axis (SVA). Full body low-dose lateral view radiographs were analyzed and classified according to three main types: Type 1A: preserved LL and SL; Type 1B: preserved LL and reduced SL (≤5°); Type 2A: PI-LL ≥10° without pelvic compensation (PT <25°); Type 2B: PI-LL ≥10° with pelvic compensation (PT ≥25°); Type 3: global sagittal malalignment (SVA ≥40 mm). The three observers classified radiographs twice with a 3-week interval for intraobserver reproducibility. Interobserver reproducibility was calculated using Fleiss κ and intra-class coefficient. Intraobserver reproducibility was calculated using Cohen κ.nnnRESULTSnMean age was 68.8 ± 9.8 years. Mean sagittal alignment parameters values were the following: PI: 60.1° ± 12.7°; PI-LL was 12.2° ± 13.9°, PT: 24.7° ± 8.5°; SVA: 44.9 mm ± 44.6 mm; SL: 16.6° ± 8.4°. Intraobserver repeatability showed an almost perfect agreement (ICC > 0.92 and Cohen κ > 0.89 for each observer). Fleiss κ value for interobserver reproducibility was 0.82, with percentage agreement among observers between 88% and 89%.nnnCONCLUSIONnThis new classification showed an excellent inter- and intraobserver reliability. This simple method could be an additional sagittal balance tool helping surgeons improve their preoperative DSLS analysis.STUDY DESIGNnInter- and intraobserver reliability study.nnnOBJECTnTo assess the reliability of a new radiographic classification of degenerative spondylolisthesis of the lumbar spine (DSLS). DSLS is a common cause of chronic low back and leg pain in adults. To this date, there is no consensus for a comprehensive analysis of DSLS. The reliability of a new DSLS classification system based on sagittal alignment was assessed.nnnMETHODSnNinety-nine patients admitted to our spinal surgery department for surgical treatment of DSLS between January 2012 and December 2015 were included. Three observers measured sagittal alignment parameters with validated software: segmental lordosis (SL), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), and sagittal vertical axis (SVA). Full body low-dose lateral view radiographs were analyzed and classified according to three main types: Type 1A: preserved LL and SL; Type 1B: preserved LL and reduced SL (≤5°); Type 2A: PI-LL ≥10° without pelvic compensation (PT <25°); Type 2B: PI-LL ≥10° with pelvic compensation (PT ≥25°); Type 3: global sagittal malalignment (SVA ≥40 mm). The three observers classified radiographs twice with a 3-week interval for intraobserver reproducibility. Interobserver reproducibility was calculated using Fleiss κ and intra-class coefficient. Intraobserver reproducibility was calculated using Cohen κ.nnnRESULTSnMean age was 68.8 ± 9.8 years. Mean sagittal alignment parameters values were the following: PI: 60.1° ± 12.7°; PI-LL was 12.2° ± 13.9°, PT: 24.7° ± 8.5°; SVA: 44.9 mm ± 44.6 mm; SL: 16.6° ± 8.4°. Intraobserver repeatability showed an almost perfect agreement (ICC > 0.92 and Cohen κ > 0.89 for each observer). Fleiss κ value for interobserver reproducibility was 0.82, with percentage agreement among observers between 88% and 89%.nnnCONCLUSIONnThis new classification showed an excellent inter- and intraobserver reliability. This simple method could be an additional sagittal balance tool helping surgeons improve their preoperative DSLS analysis.

Outpatient anterior cervical discectomy: A French study and literature review

INTRODUCTIONnIn France, surgery for lumbar disc herniation is now being done in the outpatient ambulatory setting at select facilities. However, surgery for the cervical spine in this setting is controversial because of the dangers of neck hematoma. We wanted to share our experience with performing ambulatory anterior cervical discectomy in 30 patients at our facility.nnnRESULTSnSince 2014, 30 patients (16 men, 14 women; mean age of 47.2 years) with cervical radiculopathy due to single-level cervical disc disease (19 at C5-C6 and 11 at C6-C7) were operated at our ambulatory surgery center. After anterior cervical discectomy, cervical disc replacement was performed in 13 patients and fusion in 17 patients. The mean operative time was 38minutes and the mean duration of postoperative monitoring was 7hours 30minutes. The patients stayed at the healthcare facility for an average of 10hours 10minutes. One female patient (3%) was transferred to a standard hospital unit due to a neurological deficit requiring surgical revision with no cause identified. Two patients (7%) were rehospitalized on Day 1 due to dysphagia that resolved spontaneously. Thus the ambulatory success rate was 90% (27/30). There were no other complications and the overall satisfaction rate was excellent (9.6/10).nnnDISCUSSIONnOutpatient anterior cervical discectomy is now widely performed in the United States. Ours is the first study of French patients undergoing this procedure. The complication rate was very low (<2%) and even lower than patients treated in an inpatient hospital setting in comparative studies. Note that our patients were carefully selected for outpatient surgery as certain risk factors for complications have previously been identified (age, 3+levels, comorbidities/ASA>2). No deaths in the first 30 days postoperative have been reported in the literature. Wound hematoma leading to airway compromise is rare in the ambulatory setting (0.2%). The few cases that occurred were detected early and the hematoma drained before the patient was discharged. Dysphagia is actually the most common complication (8 to 30%).nnnCONCLUSIONnCervical spine surgery can be performed in an ambulatory surgery center in carefully selected patients. Our criteria are patients less than 65 years of age, single-level disease, ASA<2, and standard cervical morphology. The complication and readmission rates are low. Careful hemostasis combined with close postoperative monitoring for at least 6hours helps to reduce the risk of neck hematoma. Prevention of postoperative dysphagia must be a focus of the care provided.

Influence of posture on relationships between pelvic parameters and lumbar lordosis: Comparison of the standing, seated, and supine positions. A preliminary study

BACKGROUNDnPelvic incidence (PI) is an anatomical parameter that is considered invariable in a given individual. Although changes in posture influence the mobile lumbar spine, lumbar lordosis (LL) and the pelvis are typically evaluated only in the standing position. Thus, whether other positions commonly used during daily activities influence the relationship between LL and PI is unknown. The objective of this study was to determine whether LL and sacral slope (SS) correlated with PI, using two standardised positions, seated and supine, different from the standing position that is generally used.nnnHYPOTHESISnWe are supposing that lumbar lordosis and sacral sloop are correlated to pelvic incidence whatever the posture. The goal of this study was to confirm or deny this hypothesis, using two standardize positions (sitting and lying) different that the usual standing position. LL and SS correlate with PI in the standing, seated, and supine positions.nnnMETHODnLumbar and pelvic parameters were measured on radiographs obtained in the standing, seated, and supine positions in 15 asymptomatic adult volunteers younger than 50years of age. Mean values with their standard deviations were computed and compared across the three positions using ANOVA. Spearmans test was applied to assess correlations.nnnRESULTSnPI had the same value in all three positions. The L1-S1 LL angle was 54.8±9.8° in the standing position, 15.9±14.6° in the seated position, and 50.2±9.6° in the supine position. Pelvic tilt (PT) in the same three positions was 12.1±6.3°, 37.7±10.4°, and 9.5±5.1°, respectively; and SS was 37.1±6.3°, 11.3±10.8°, and 41±7.2°, respectively. Correlations were strongest in the supine position between PI and LL (r=0.72), LL and SS (r=0.9), and PI and SS (r=0.84).nnnCONCLUSIONnWhereas PI remains unchanged in a given individual, lumbar lordosis and sacral orientation show significant changes across positions used in daily life, with the greatest changes seen in the seated position. During spinal fusion surgery, adjusting LL based on IP is crucial even in patients who have limited physical activity.nnnLEVEL OF EVIDENCEnIV.

Spondylolisthesis adjacent to a cervical disc arthroplasty does not increase the risk of adjacent level degeneration

PurposeTo understand whether a spondylolisthesis in the sub-axial spine cranial to a cervical disc arthroplasty (CDA) construes a risk of adjacent level disease (ALD).MethodsA retrospective review of 164 patients with a minimum 5-year follow-up of a cervical disc arthroplasty was performed. Multi-level surgeries, including hybrid procedures, were included. Multiple implant types were included. The two inter-vertebral discs (IVD) cranial of the CDA were monitored for evidence of radiologic degeneration using the Kettler criteria.ResultsThe rate of ALD in CDA found in this series was 17.8%, with most affecting the immediately adjacent IVD (27.4 and 7.6%, respectively pu2009=u20090.000). Pre-operative mild spondylolisthesis adjacent to a planned CDA was not found to be a risk factor for ALD within 5xa0years. Those with a degenerative spondylolisthesis are at higher risk of ALD (33%) than those with a non-degenerative cause for their spondylolisthesis (11%). Post-operative CDA alignment, ROM or induced spondylolisthesis do not affect the rate of ALD in those with an adjacent spondylolisthesis. Patients with ALD experience significantly worse 5-year pain and functional outcomes than those unaffected by ALD.ConclusionsA pre-operatively identified mild spondylolisthesis in the sub-axial spine cranially adjacent to a planned CDA is not a risk factor for ALD within 5xa0years.Graphical abstractThese slides can be retrieved under Electronic Supplementary Material.

Identifying the superior and inferior gluteal arteries during a sacrectomy via a posterior approach

BackgroundnIdentifying the gluteal vessels during a posterior sacrectomy can be challenging. This study defines anatomical landmarks that can be used to approximate the location of the superior and inferior gluteal arteries (SGA and IGA) during a posterior sacrectomy.nnnMethodsnCadaveric dissection of six fresh adult pelvises to determine the location of the SGA and IGA in relation to the posterior-inferior aspect of the sacroiliac joint (PISIJ), lateral sacral margin and sacrococcygeal joint (SCJ).nnnResultsnThe anatomical landmarks are easily palpable. The position of the SGA to the PISIJ is relatively constant as it is tethered by a posterior branch of the artery, which runs inferior to the PISIJ. The IGA position is also relatively constant below the mid-point of the PISIJ and SCJ. The vessels are separated from the sacrospinous/sacrotuberous ligament complex (SSTL) in the perisacral region and as a result an anatomical plane exists anterior to the SSTL, which affords protection of the vessels during SSTL transection. The distance between the vessels and the SSTL increases the more medial the dissection.nnnConclusionsnThe described anatomical landmarks can be used to predict the location of the SGA and IGA during posterior sacrectomy. An anatomical plane exists anterior to the SSTL, which provides protection to the vessels during SSTL transection. Furthermore, the distance between the vessels and the SSTL increases the more medial the dissection, thus, resection of the SSTL as close to the lateral sacral margin as the pathology permits, is advocated.