1
|
Sawitzke JA, Costantino N, Li XT, Thomason LC, Bubunenko M, Court C, Court DL. Probing cellular processes with oligo-mediated recombination and using the knowledge gained to optimize recombineering. J Mol Biol 2011; 407:45-59. [PMID: 21256136 PMCID: PMC3046259 DOI: 10.1016/j.jmb.2011.01.030] [Citation(s) in RCA: 128] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Revised: 01/12/2011] [Accepted: 01/13/2011] [Indexed: 11/25/2022]
Abstract
Recombination with single-strand DNA oligonucleotides (oligos) in Escherichia coli is an efficient and rapid way to modify replicons in vivo. The generation of nucleotide alteration by oligo recombination provides novel assays for studying cellular processes. Single-strand exonucleases inhibit oligo recombination, and recombination is increased by mutating all four known exonucleases. Increasing oligo concentration or adding nonspecific carrier oligo titrates out the exonucleases. In a model for oligo recombination, λ Beta protein anneals the oligo to complementary single-strand DNA at the replication fork. Mismatches are created, and the methyl-directed mismatch repair (MMR) system acts to eliminate the mismatches inhibiting recombination. Three ways to evade MMR through oligo design include, in addition to the desired change (1) a C·C mismatch 6 bp from that change; (2) four or more adjacent mismatches; or (3) mismatches at four or more consecutive wobble positions. The latter proves useful for making high-frequency changes that alter only the target amino acid sequence and even allows modification of essential genes. Efficient uptake of DNA is important for oligo-mediated recombination. Uptake of oligos or plasmids is dependent on media and is 10,000-fold reduced for cells grown in minimal versus rich medium. Genomewide engineering technologies utilizing recombineering will benefit from both optimized recombination frequencies and a greater understanding of how biological processes such as DNA replication and cell division impact recombinants formed at multiple chromosomal loci. Recombination events at multiple loci in individual cells are described here.
Collapse
|
Research Support, N.I.H., Extramural |
14 |
128 |
2
|
Court C, Colliou OK, Chin JR, Liebenberg E, Bradford DS, Lotz JC. The effect of static in vivo bending on the murine intervertebral disc. Spine J 2001; 1:239-45. [PMID: 14588327 DOI: 10.1016/s1529-9430(01)00056-0] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT Intervertebral disc cell function in vitro has been linked to features of the local environment that can be related to deformation of the extracellular matrix. Epidemiologic data suggest that certain regimens of spinal loading accelerate disc degeneration in vivo. Yet, the direct association between disc cell function, spinal loading and ultimately tissue degeneration is poorly characterized. PURPOSE To examine the relationships between tensile and compressive matrix strains, cell activity and annular degradation. STUDY DESIGN/SETTING An in vivo study of the biologic, morphologic and biomechanical consequences of static bending applied to the murine intervertebral disc. SUBJECT SAMPLE: Twenty-five skeletally mature Swiss Webster mice (12-week-old males) were used in this study. OUTCOME MEASURES Bending neutral zone, bending stiffness, yield point in bending, number of apoptotic cells, annular matrix organization, cell shape, aggrecan gene expression, and collagen II gene expression. METHODS Mouse tail discs were loaded for 1 week in vivo with an external device that applied bending stresses. Mid-sagittal sections of the discs were analyzed for cell death, collagen II and aggrecan gene expression, and tissue organization. Biomechanical testing was also performed to measure the bending stiffness and strength. RESULTS Forceful disc bending induced increased cell death, decreased aggrecan gene expression and decreased tissue organization preferentially on the concave side. By contrast, collagen II gene expression was symmetrically reduced. Asymmetric loading did not alter bending mechanical behavior of the discs. CONCLUSIONS In this model, annular cell death was related to excessive matrix compression (as opposed to tension). Collagen II gene expression was most negatively influenced by the static nature of the loading (immobilization), rather than the specific state of stress (tension or compression).
Collapse
|
Comparative Study |
24 |
75 |
3
|
Court C, Mansour E, Bouthors C. Thoracic disc herniation: Surgical treatment. Orthop Traumatol Surg Res 2018; 104:S31-S40. [PMID: 29225115 DOI: 10.1016/j.otsr.2017.04.022] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 04/20/2017] [Accepted: 04/21/2017] [Indexed: 02/02/2023]
Abstract
Thoracic disc herniation is rare and mainly occurs between T8 and L1. The herniation is calcified in 40% of cases and is labeled as giant when it occupies more than 40% of the spinal canal. A surgical procedure is indicated when the patient has severe back pain, stubborn intercostal neuralgia or neurological deficits. Selection of the surgical approach is essential. Mid-line calcified hernias are approached from a transthoracic incision, while lateralized soft hernias can be approached from a posterolateral incision. The complication rate for transthoracic approaches is higher than that of posterolateral approaches; however, the former are performed in more complex herniation cases. The thoracoscopic approach is less invasive but has a lengthy learning curve. Retropleural mini-thoracotomy is a potential compromise solution. Fusion is recommended in cases of multilevel herniation, herniation in the context of Scheuermann's disease, when more than 50% bone is resected from the vertebral body, in patients with preoperative back pain or herniation at the thoracolumbar junction. Along with complications specific to the surgical approach, the surgical risks are neurological worsening, dural breach and subarachnoid-pleural fistulas. Giant calcified herniated discs are the largest contributor to myelopathy, intradural extension and postoperative complications. Some of the technical means that can be used to prevent complications are explored, along with how to address these complications.
Collapse
|
Lecture |
7 |
65 |
4
|
Abstract
STUDY DESIGN A retrospective review of a clinical series was performed. OBJECTIVES To evaluate the incidence of adult patients who experienced spinal collapse after spinal implant removal after a long spinal arthrodesis, and to assess the various factors that may influence the likelihood of collapse after implant removal. SUMMARY OF BACKGROUND DATA Published reports describing the benefits or complications of spinal implant removal do not exist. Spinal implant removal, often considered a benign procedure, is even required by the Food and Drug Administration (FDA) for certain implants. METHODS The medical records and radiographs of 116 consecutive adult patients with long posterior instrumented fusions (>5 segments) were reviewed. The information obtained included original diagnosis, patient age, number of previous surgeries before implant removal, levels of anterior and posterior fusion, time from fusion to implant removal, time from implant removal to failure, and reason for hardware removal. Radiographs also were assessed including scoliosis, lordosis, and kyphosis measurements before implant removal, after hardware removal, after failure, and after revision surgery. RESULTS Of 116 patients, 14 underwent spinal implant removal. Most of these patients reported prominent implants either proximally in the thoracic spine or distally in the ilium (Galveston technique). Of these 14 patients, 4 experienced increased pain and collapse after implant removal despite thorough intraoperative explorations demonstrating solid fusion. CONCLUSIONS Spinal implant removal after long posterior fusion in adults may lead to spinal collapse and further surgery. Removal of instrumentation should be avoided or should involve partial removal of the prominent implant.
Collapse
|
Case Reports |
25 |
63 |
5
|
Court C, Vincent C. Percutaneous fixation of thoracolumbar fractures: current concepts. Orthop Traumatol Surg Res 2012; 98:900-9. [PMID: 23165222 DOI: 10.1016/j.otsr.2012.09.014] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Accepted: 09/29/2012] [Indexed: 02/02/2023]
Abstract
Numerous improvements in minimally invasive spine surgery (MISS) have been made during the last decade. MISS in thoracolumbar spine trauma management must achieve the same results as conventional treatment but with less morbidity. The increased use of MISS technologies in spine trauma has been correlated to the availability of more versatile instrumentation, which makes the fixation of all thoracic and lumbar levels possible. Balloon-assisted techniques have been used to support the anterior column in a stand-alone manner or in combination with open or percutaneous pedicle screw fixation. Fluoroscopy-assisted pedicle screw insertion is associated with less pedicle wall violation when compared to open surgery, but with increased radiation exposure for the surgeon and patient. Surgeons must be aware of this issue and new technologies are available to decrease irradiation. The advantages of percutaneous pedicle screw fixation relative to open surgery are discussed: preservation of posterior musculature, less blood loss, shorter operative time, lower infection risk, less postoperative pain, shorter rehabilitation time as well as shorter hospital stay. Limitations of percutaneous fixation include the inability to achieve direct spinal canal decompression and not having the option to perform a fusion. Nevertheless, these limitations can be addressed by combining MISS with open techniques. Indications for percutaneous spine fixation alone or in combination with MISS or open techniques are discussed based on the AO classification. The benefits of percutaneous spinal fixation for unstable spine fractures in polytrauma patients are also discussed. Posterior instrumentation can be easily removed after bone union to allow young patients to regain their mobility. Large well-controlled prospective studies are needed to draw up guidelines for less invasive procedures in spine trauma. In the future, development of new technologies can expand the scope of indications and treatment possibilities using MISS techniques in spine trauma.
Collapse
|
Review |
13 |
56 |
6
|
Zhou YN, Lubkowska L, Hui M, Court C, Chen S, Court DL, Strathern J, Jin DJ, Kashlev M. Isolation and characterization of RNA polymerase rpoB mutations that alter transcription slippage during elongation in Escherichia coli. J Biol Chem 2013; 288:2700-10. [PMID: 23223236 PMCID: PMC3554936 DOI: 10.1074/jbc.m112.429464] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Indexed: 01/05/2023] Open
Abstract
Transcription fidelity is critical for maintaining the accurate flow of genetic information. The study of transcription fidelity has been limited because the intrinsic error rate of transcription is obscured by the higher error rate of translation, making identification of phenotypes associated with transcription infidelity challenging. Slippage of elongating RNA polymerase (RNAP) on homopolymeric A/T tracts in DNA represents a special type of transcription error leading to disruption of open reading frames in Escherichia coli mRNA. However, the regions in RNAP involved in elongation slippage and its molecular mechanism are unknown. We constructed an A/T tract that is out of frame relative to a downstream lacZ gene on the chromosome to examine transcriptional slippage during elongation. Further, we developed a genetic system that enabled us for the first time to isolate and characterize E. coli RNAP mutants with altered transcriptional slippage in vivo. We identified several amino acid residues in the β subunit of RNAP that affect slippage in vivo and in vitro. Interestingly, these highly clustered residues are located near the RNA strand of the RNA-DNA hybrid in the elongation complex. Our E. coli study complements an accompanying study of slippage by yeast RNAP II and provides the basis for future studies on the mechanism of transcription fidelity.
Collapse
|
Research Support, N.I.H., Extramural |
12 |
51 |
7
|
Court C, Bosca L, Le Cesne A, Nordin JY, Missenard G. Surgical excision of bone sarcomas involving the sacroiliac joint. Clin Orthop Relat Res 2006; 451:189-194. [PMID: 16770289 DOI: 10.1097/01.blo.0000229279.58947.91] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Adequate (wide or marginal and uncontaminated) margins and reconstruction are difficult to achieve when performing an internal hemipelvectomy for bone sarcomas involving the sacroiliac joint. We evaluated whether adequate surgical margins could be achieved and if functional outcomes could be predicted based on the type of resection and reconstruction. Forty patients had resections of the sacroiliac joint. Vertical sacral osteotomies were through the sacral wing (n = 2), ipsilateral sacral foramina (n = 27), sacral midline (n = 9), or contralateral foramina (n = 2). Iliac resections were Type I, Type I-II with partial or total acetabular re-section, or Type I-II-III. Surgical margins were adequate in 28 of 38 patients (74%), two (7%) of whom experienced local recurrence, compared with seven of 10 (70%) patients with inadequate margins. Reconstruction consisted of restoring continuity between the spine and pelvis. Resection of the entire acetabulum and removal of the lumbosacral trunk were the two main determinants of function, as assessed using the Musculoskeletal Tumor Society score. There were no life-threatening or function-threatening complications. Internal hemipelvectomy with a limb salvage procedure can be achieved with adequate surgical margins in selected patients. Functional outcomes can be predicted based on the type of resection and reconstruction, which helps the surgeon plan the procedure and inform the patient.
Collapse
|
|
19 |
40 |
8
|
Roquilly A, Vigué B, Boutonnet M, Bouzat P, Buffenoir K, Cesareo E, Chauvin A, Court C, Cook F, de Crouy AC, Denys P, Duranteau J, Fuentes S, Gauss T, Geeraerts T, Laplace C, Martinez V, Payen JF, Perrouin-Verbe B, Rodrigues A, Tazarourte K, Prunet B, Tropiano P, Vermeersch V, Velly L, Quintard H. French recommendations for the management of patients with spinal cord injury or at risk of spinal cord injury. Anaesth Crit Care Pain Med 2020; 39:279-289. [PMID: 32229270 DOI: 10.1016/j.accpm.2020.02.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
OBJECTIVES To update the French guidelines on the management of trauma patients with spinal cord injury or suspected spinal cord injury. DESIGN A consensus committee of 27 experts was formed. A formal conflict-of-interest (COI) policy was developed at the outset of the process and enforced throughout. The entire guidelines process was conducted independently of any industrial funding (i.e. pharmaceutical, medical devices). The authors were advised to follow the rules of the Grading of Recommendations Assessment, Development and Evaluation (GRADE®) system to guide assessment of quality of evidence. The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasised. METHODS The committee studied twelve questions: (1) What are the indications and arrangements for spinal immobilisation? (2) What are the arrangements for pre-hospital orotracheal intubation? (3) What are the objectives of haemodynamic resuscitation during the lesion assessment, and during the first few days in hospital? (4) What is the best way to manage these patients to improve their long-term prognosis? (5) What is the place of corticosteroid therapy in the initial phase? (6) What are the indications for magnetic resonance imaging in the lesion assessment phase? (7) What is the optimal time for surgical management? (8) What are the best arrangements for orotracheal intubation in the hospital environment? (9) What are the specific conditions for weaning these patients from mechanical ventilation for? (10) What are the procedures for analgesic treatment of these patients? (11) What are the specific arrangements for installing and mobilising these patients? (12) What is the place of early intermittent bladder sampling in these patients? Each question was formulated in a PICO (Patients, Intervention, Comparison, Outcome) format and the evidence profiles were produced. The literature review and recommendations were made according to the GRADE® Methodology. RESULTS The experts' work synthesis and the application of the GRADE method resulted in 19 recommendations. Among the recommendations formalised, 2 have a high level of evidence (GRADE 1+/-) and 12 have a low level of evidence (GRADE 2+/-). For 5 recommendations, the GRADE method could not be applied, resulting in expert advice. After two rounds of scoring and one amendment, strong agreement was reached on all the recommendations. CONCLUSIONS There was significant agreement among experts on strong recommendations to improve practices for the management of patients with spinal cord injury.
Collapse
|
Practice Guideline |
5 |
39 |
9
|
Vialle R, Court C, Khouri N, Olivier E, Miladi L, Tassin JL, Defives T, Dubousset J. Anatomical study of the paraspinal approach to the lumbar spine. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2005; 14:366-71. [PMID: 15526219 PMCID: PMC3489211 DOI: 10.1007/s00586-004-0802-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2004] [Revised: 06/28/2004] [Accepted: 08/18/2004] [Indexed: 11/26/2022]
Abstract
The original description of the paraspinal posterior approach to the lumbar spine was for spinal fusion, especially regarding lumbosacral spondylolisthesis treatment. In spite of the technical details described by Wiltse, exact location of the area where the sacrospinalis muscle has to be split remains somewhat unclear. The goal of this study was to provide topographic landmarks to facilitate this surgical approach. Thirty cadavers were dissected in order to precisely describe the anatomy of the trans-muscular paraspinal approach. The level of the natural cleavage plane between the multifidus and the longissimus part of the sacrospinalis muscle was noted and measurements were done between this level and the midline at the level of the spinous process of L4. A natural cleavage plane between the multifidus and the longissimus part of the sacrospinalis muscle was present in all cases. There was a fibrous separation between the two muscular parts in 55 out of 60 cases. The mean distance between the level of the cleavage plane and the midline was 4 cm (2.4-5.5 cm). In all cases, small arteries and veins were present, precisely at the level of the cleavage plane. We found it possible to easily localize the anatomical cleavage plane between the multifidus part and the longissimus part of the sacrospinalis muscle. First the superficial muscular fascia is opened near the midline, exposing the posterior aspect of the sacrospinalis muscle. Then, the location of the muscular cleft can be found by identifying the perforating vessels leaving the anatomical inter-muscular space.
Collapse
|
research-article |
20 |
38 |
10
|
Garnier L, Tonetti J, Bodin A, Vouaillat H, Merloz P, Assaker R, Court C. Kyphoplasty versus vertebroplasty in osteoporotic thoracolumbar spine fractures. Short-term retrospective review of a multicentre cohort of 127 consecutive patients. Orthop Traumatol Surg Res 2012; 98:S112-9. [PMID: 22939104 DOI: 10.1016/j.otsr.2012.03.018] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Revised: 03/19/2012] [Accepted: 03/28/2012] [Indexed: 02/02/2023]
Abstract
BACKGROUND Osteoporotic spine fractures induce a heavy burden in terms of both general health and healthcare costs. The objective of this multicentre study by the French Society for Spine Surgery (SFCR) was to compare outcomes after vertebroplasty and kyphoplasty in the treatment of osteoporotic thoracolumbar vertebral fractures. HYPOTHESIS We hypothesised that differences existed between vertebroplasty and kyphoplasty, notably regarding operative time and reduction efficacy, from which criteria for patient selection might be inferred. MATERIAL AND METHODS We conducted a retrospective multicentre review of 127 patients with Magerl Type A low-energy fractures after a fall from standing height between 2007 and 2010; 85 were managed with vertebroplasty and 42 with kyphoplasty. Age was not a selection criterion. We recorded pain intensity, time to management, operative time, kyphosis angle, wedge angle, cement leakage rate, and degree of cement filling. RESULTS Operative time was 43 minutes with kyphoplasty and 24 minutes with vertebroplasty (P=0.0002). Both techniques relieved pain, with no significant difference. Kyphoplasty significantly improved the wedge angle, by +6°, versus +2° with vertebroplasty (P=0.002). With kyphoplasty, the volume injected was larger and cement distribution was less favourable. Leakage rates were similar. DISCUSSION Despite the heterogeneity of our study, our data confirm the effectiveness of kyphoplasty in alleviating pain and decreasing deformities due to osteoporotic vertebral fractures. Vertebroplasty is a faster and less costly procedure that remains useful; no detectable clinical complications occur with vertebroplasty, which ensures better anchoring of the cement in the cancellous bone.
Collapse
|
Comparative Study |
13 |
23 |
11
|
Zairi F, Court C, Tropiano P, Charles YP, Tonetti J, Fuentes S, Litrico S, Deramond H, Beaurain J, Orcel P, Delecrin J, Aebi M, Assaker R. Minimally invasive management of thoraco-lumbar fractures: combined percutaneous fixation and balloon kyphoplasty. Orthop Traumatol Surg Res 2012; 98:S105-11. [PMID: 22901522 DOI: 10.1016/j.otsr.2012.06.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Accepted: 06/21/2012] [Indexed: 02/02/2023]
Abstract
STUDY DESIGN Retrospective review of prospectively collected data. BACKGROUND There is no consensus regarding the ideal treatment of thoraco-lumbar spine fractures without neurological compromise. Many surgical techniques have been described but none has proved its definite superiority. The main drawback of these procedures is directly related to the morbidity of the approach. As minimally invasive fixation combined with balloon kyphoplasty for treatment of thoraco-lumbar fractures is gaining popularity, its efficacy has yet to be established. PURPOSE The purpose of this study is to report operative data, clinical and radiological outcomes of patients undergoing minimally invasive management of thoraco-lumbar fracture at our institutions. METHODS Forty-one patients underwent percutaneous kyphoplasty and stabilization for treatment of single-level fracture of the thoracic or lumbar spine. All patients were neurologically intact. There were 20 males and 21 females with an average age of 50 years. RESULTS The mean follow-up was 15 months (3-90 months). The mean operative time was 102 minutes (range 35-240 minutes) and the mean blood loss was <100mL. VAS was significantly improved from 6.7 to 0.7 at last follow-up. Vertebral kyphosis decreased by 16° to 7.8° postoperatively (P<0.001). Local kyphosis and percentage of collapse were also significantly improved from 8° to 5.6° and from 35% to 16% at last follow-up. Fifteen leaks have been identified, three of which were posterior; all remained asymptomatic. No patient worsened his or her neurological condition postoperatively. CONCLUSION Percutaneous stabilization plus balloon kyphoplasty seems to be a safe and effective technique to manage thoraco-lumbar fractures without neurological impairment.
Collapse
|
|
13 |
23 |
12
|
Bel JC, Court C, Cogan A, Chantelot C, Piétu G, Vandenbussche E. Unicondylar fractures of the distal femur. Orthop Traumatol Surg Res 2014; 100:873-7. [PMID: 25453913 DOI: 10.1016/j.otsr.2014.10.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 08/30/2014] [Indexed: 02/02/2023]
Abstract
BACKGROUND Unicondylar fractures of the distal femur are rare, complex, intra-articular fractures. The objective of this multicentre study was to assess the reduction and fixation of unicondylar fractures. HYPOTHESIS Anatomic reduction followed by strong fixation allows early rehabilitation therapy and provides good long-term outcomes. MATERIAL AND METHODS We studied 163 fractures included in two multicentre studies, of which one was retrospective (n=134) and the other prospective (n=29). Follow-up of at least 1 year was required for inclusion. The treatment was at the discretion of the surgeon. Outcome measures were the clinical results assessed using the International Knee Society (IKS) scores and presence after fracture healing of malunion with angulation, an articular surface step-off, and/or tibio-femoral malalignment. RESULTS Mean age of the study patients was 50.9 ± 24 years, and most patients were males with no previous history of knee disorders. The fracture was due to a high-energy trauma in 51% of cases; 17% of patients had compound fractures and 44% multiple fractures or injuries. The lateral and medial condyles were equally affected. The fracture line was sagittal in 82% of cases and coronal (Hoffa fracture) in 18% of cases. Non-operative treatment was used in 5% of cases and internal fixation in 95% of cases, with either direct screw or buttress-plate fixation for the sagittal fractures and either direct or indirect screw fixation for the coronal fractures. After treatment of the fracture, 15% of patients had articular malunion due to insufficient reduction, with either valgus-varus (10%) or flexion-recurvatum (5%) deformity; and 12% of patients had an articular step-off visible on the antero-posterior or lateral radiograph. Rehabilitation therapy was started immediately in 65% of patients. Time to full weight bearing was 90 days and time to fracture healing 120 days. Complications consisted of disassembly of the construct (2%), avascular necrosis of the condyle (2%), and arthrolysis (5%). The material was removed in 11% of patients. At last follow-up, the IKS knee score was 71 ± 20 and the IKS function score 64 ± 7; flexion range was 106 ± 28° (<90° in 27% of patients); and 12% of patients had knee osteoarthritis. CONCLUSION Anatomic reduction of unicondylar distal femoral fractures via an appropriate surgical approach, followed by stable internal fixation using either multiple large-diameter screws or a buttress-plate, allows immediate mobilisation, which in turn ensures good long-term outcomes. LEVEL OF EVIDENCE IV, cohort study.
Collapse
|
Multicenter Study |
11 |
21 |
13
|
Court C, Vialle R, Lepeintre JF, Tadié M. The thoracoabdominal intercostal nerves: an anatomical study for their use in neurotization. Surg Radiol Anat 2004; 27:8-14. [PMID: 15316761 DOI: 10.1007/s00276-004-0281-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2004] [Accepted: 05/28/2004] [Indexed: 10/26/2022]
Abstract
The topographic anatomy of the lower intercostal nerves is less known than that of the upper ones, except for the subcostal nerve (twelfth intercostal nerve). It is possible to use the lower intercostal nerves to neurotize the lumbar roots. We studied the anatomy of the ninth, tenth and eleventh intercostal nerves in order to specify the descriptive and topographical anatomical data that will allow their harvest in good condition. The ninth, tenth and eleventh intercostal nerves of 30 cadavers were dissected. The proximal part of the nerves in the posterior intercostal space was exposed through a posterior approach. The lateral intercostal space was exposed through a lateral approach, deep to the latissimus dorsi, that made it possible to harvest the intercostal nerve. The proximal course of the nerves in the posterior intercostal space was the same in all cases. The nerves move obliquely towards the outside to reach the lower border of the rib. The exit of the posterior intercostal space is a fibrous strait, which marks the entry of a channel between two muscular layers. We describe an aponeurotic channel in which the nerve and vessels run, immediately at the lower border of the cranial rib. The mean total length of intercostal nerve harvested by our technique was 17.86 cm for the ninth intercostal nerve, 16.95 cm for the tenth and 15.75 cm for the eleventh. Bifurcation of the intercostal nerve into a deep branch and the lateral cutaneous branch was found in the majority of the cases, 9.5-21 cm from the emergence of the intercostal nerve in the posterior intercostal space. This anatomical study of the ninth, tenth and eleventh intercostal nerves in the posterior intercostal and lateral intercostal spaces appears to us to allow reliable surgical harvesting.
Collapse
|
|
21 |
20 |
14
|
Parks AR, Court C, Lubkowska L, Jin DJ, Kashlev M, Court DL. Bacteriophage λ N protein inhibits transcription slippage by Escherichia coli RNA polymerase. Nucleic Acids Res 2014; 42:5823-9. [PMID: 24711367 PMCID: PMC4027172 DOI: 10.1093/nar/gku203] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Transcriptional slippage is a class of error in which ribonucleic acid (RNA) polymerase incorporates nucleotides out of register, with respect to the deoxyribonucleic acid (DNA) template. This phenomenon is involved in gene regulation mechanisms and in the development of diverse diseases. The bacteriophage λ N protein reduces transcriptional slippage within actively growing cells and in vitro. N appears to stabilize the RNA/DNA hybrid, particularly at the 5′ end, preventing loss of register between transcript and template. This report provides the first evidence of a protein that directly influences transcriptional slippage, and provides a clue about the molecular mechanism of transcription termination and N-mediated antitermination.
Collapse
|
Research Support, N.I.H., Intramural |
11 |
19 |
15
|
Bouthors C, Prost S, Court C, Blondel B, Charles YP, Fuentes S, Mousselard HP, Mazel C, Flouzat-Lachaniette CH, Bonnevialle P, Saihlan F. Outcomes of surgical treatments of spinal metastases: a prospective study. Support Care Cancer 2019; 28:2127-2135. [PMID: 31396747 DOI: 10.1007/s00520-019-05015-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 07/30/2019] [Indexed: 11/30/2022]
Abstract
BACKGROUND Owing to recent advances in cancer therapy, updated data are required for clinicians counselling patients on treatment of spinal metastases. OBJECTIVE To analyse the outcomes of surgical treatments of spinal metastases. METHODS Prospective and multicentric study that included consecutively patients operated on for spinal metastases between January 2016 and January 2017. Overall survival was calculated with the Kaplan-Meier method. Cox proportional hazard model was used to calculate hazard ratio (HR) analysing mortality risk according to preoperative Karnofsky performance status (KPS), mobility level and neurological status. RESULTS A total of 252 patients were included (145 males, 107 females) aged a mean 63.3 years. Median survival was 450 days. Primary cancer sites were lung (21%) and breast (19%). Multiple spinal metastases involved 122 patients (48%). Concomitant skeletal and visceral metastases were noted in 90 patients (36%). Main procedure was laminectomy and posterior fixation (57%). Overall, pain and mobility level were improved postoperatively. Most patients had normal preoperative motor function (50%) and remained so postoperatively. Patients "bedbound" on admission were the less likely to recover. In-hospital death rate was 2.4% (three disease progression, one septic shock, one pneumonia, one pulmonary embolism). Complication rate was 33%, deep wound infection was the most frequent aetiology. Higher mortality was observed in patients with poorest preoperative KPS (KPS 0-40%, HR = 3.1, p < 0.001) and mobility level ("bedbound", HR = 2.16, p < 0.001). Survival seemed also to be linked to preoperative neurological function. CONCLUSION Surgical treatments helped maintain reasonable condition for patients with spinal metastases. Intervention should be offered before patients' condition worsen to ensure better outcomes.
Collapse
|
Multicenter Study |
6 |
11 |
16
|
|
News |
31 |
11 |
17
|
Tempelaere C, Vincent C, Court C. Percutaneous posterior fixation for unstable pelvic ring fractures. Orthop Traumatol Surg Res 2017; 103:1169-1171. [PMID: 28964921 DOI: 10.1016/j.otsr.2017.07.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 07/11/2017] [Accepted: 07/25/2017] [Indexed: 02/02/2023]
Abstract
UNLABELLED Several posterior fixation techniques for unstable pelvic ring fractures have been described. Here, we present a minimally invasive, percutaneous technique to fix the two posterior iliac crests using spinal instrumentation. Between September 2008 and March 2012, 11 patients with a mean age of 36.4 years were operated because of a vertically unstable Tile C pelvic ring fracture. Posterior fixation was performed using two polyaxial screws in each iliac crest with two subfascial connector rods. At the final follow-up, all patients were evaluated clinically and radiologically. The mean surgery time was 45 minutes; there were no intraoperative complications. At a mean follow-up of four years, the functional Majeed score was excellent in eight patients and good in three patients. The radiological results were excellent in eight patients and good in three patients. Percutaneous posterior fixation of vertically unstable pelvic fractures leads to good functional and radiological outcomes. TYPE OF STUDY Technical note, retrospective. LEVEL OF EVIDENCE IV.
Collapse
|
|
8 |
10 |
18
|
|
News |
29 |
9 |
19
|
Court C. Britain: Incidence reduced by two thirds in five years. BMJ : BRITISH MEDICAL JOURNAL 1995. [DOI: 10.1136/bmj.310.6971.7a] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
|
30 |
9 |
20
|
Thomason LC, Schiltz CJ, Court C, Hosford CJ, Adams MC, Chappie JS, Court DL. Bacteriophage λ RexA and RexB Functions Assist the Transition from Lysogeny to Lytic Growth. Mol Microbiol 2021; 116:1044-1063. [PMID: 34379857 DOI: 10.1111/mmi.14792] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 08/04/2021] [Accepted: 08/06/2021] [Indexed: 11/26/2022]
Abstract
The CI and Cro repressors of bacteriophage λ create a bistable switch between lysogenic and lytic growth. In λ lysogens, CI repressor expressed from the PRM promoter blocks expression of the lytic promoters PL and PR to allow stable maintenance of the lysogenic state. When lysogens are induced, CI repressor is inactivated and Cro repressor is expressed from the lytic PR promoter. Cro repressor blocks PRM transcription and CI repressor synthesis to ensure that the lytic state proceeds. RexA and RexB proteins, like CI, are expressed from the PRM promoter in λ lysogens; RexB is also expressed from a second promoter, PLIT , embedded in rexA. Here we show that RexA binds CI repressor and assists the transition from lysogenic to lytic growth, using both intact lysogens and defective prophages with reporter genes under control of the lytic PL and PR promoters. Once lytic growth begins, if the bistable switch does return to the immune state, RexA expression lessens the probability that it will remain there, thus stabilizing the lytic state and activation of the lytic PL and PR promoters. RexB modulates the effect of RexA and may also help establish phage DNA replication as lytic growth ensues.
Collapse
|
Journal Article |
4 |
8 |
21
|
|
News |
30 |
7 |
22
|
Riouallon G, Molina V, Mansour C, Court C, Nordin JY. An original knee arthrodesis technique combining external fixator with Steinman pins direct fixation. Orthop Traumatol Surg Res 2009; 95:272-7. [PMID: 19473904 DOI: 10.1016/j.otsr.2009.04.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2008] [Revised: 01/10/2009] [Accepted: 04/20/2009] [Indexed: 02/02/2023]
Abstract
INTRODUCTION Knee arthrodesis may be the last possible option for infected total knee arthroplasty (TKA) patients and in revision cases involving severe bone loss and/or extensor mechanism damages. Success in these situations depends on achieving good fixation assembly stability. We report bone fusion results using a fixation technique combining cross-pinning by two Steinman pins with a single-frame external fixator. Remission of infection at long-term follow-up was an additional criteria assessed for those cases initially treated for sepsis. HYPOTHESIS This fixation modality improves fusion rates. PATIENTS AND METHODS In six of this series of eight patients (mean age: 59 years), surgery was performed in a context of infection: five cases of infected TKA, and one case of septic arthritis. In the other two cases, arthrodesis was respectively indicated for a severe post-traumatic stiffness compounded by extensor system rupture and for a fracture combined to a complete mechanical implant loosening. In three of the six infection cases, arthrodesis was performed as a single-stage procedure. All patients were operated on using the same technique: primary arthrodesis site stabilization by frontal cross-pinning with two Steinman pins, followed by installation of a sagittal external fixator frame. Results were assessed at a mean 8 year follow-up. RESULTS All the arthrodeses showed fusion at a mean 3.5 months (range: 2.5 to 6 months) postoperative delay without reintervention. Weight-bearing was resumed at 2 to 3 months. The external fixator was removed at a mean 5.2 months. No recurrence of infection was observed over a mean follow-up of 8.2 years (range: 1 to 15 years). Three complications occurred: one hematoma, managed surgically; one supracondylar fracture treated orthopedically; and one osteitis, managed by surgical curettage. DISCUSSION This knee arthrodesis technique proved effective, with no failures in this short series, especially in cases of primary infection. It is a reproducible means of osteosynthesis, with little subsequent morbidity. Fixation in two orthogonal planes seemed to provide the stability required to achieve bone fusion. This assembly avoids internal fixation, which is never risk-free in a context of primary sepsis. LEVEL OF EVIDENCE Level IV. Retrospective study.
Collapse
|
|
16 |
7 |
23
|
Vialle R, Court C, Harding I, Lepeintre JF, Khouri N, Tadié M. Multiple lumbar plexus neurotizations of the ninth, tenth, and eleventh intercostal nerves. Clin Anat 2005; 19:51-8. [PMID: 16187321 DOI: 10.1002/ca.20148] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The topographic anatomy of the lower intercostal nerves is less known than the upper ones except for the twelfth intercostal nerve. It is possible to use the lower intercostal nerves to carry out a neurotization of the lumbar roots. We studied the anatomy of the ninth, tenth, and eleventh intercostal nerves in order to specify the data of descriptive and topographic anatomy allowing to carry out their harvesting under good conditions. Ninth, tenth, and eleventh intercostal nerves of 50 cadavers were dissected. The proximal part of the nerve in the posterior intercostal space was exposed through a posterior approach. The lateral intercostal space was exposed through a lateral approach, under the latissimus dorsi, which made it possible to harvest the intercostals nerve. The proximal course of the nerve in posterior intercostals space was the same in all the cases. The nerve moves obliquely towards the outside to reach the lower border of the rib. The exit of posterior intercostal space is a fibrous strait that marks the entry of a channel between two muscular layers. We describe an aponevrotic channel in which the nerve and the vessels are, immediately at the lower border of the cranial rib. The mean total length of intercostal nerve harvested by our technique was 17.96 cm for the ninth intercostal nerve, 17.14 cm for the tenth intercostal nerve, and 15.94 cm for the eleventh intercostal nerve. The bifurcation of the intercostal nerve in a deep branch and the ramus cutaneus lateralis was found in the majority of the cases, from 9.5 to 21 cm of the emergence of the intercostal nerve in posterior intercostal space. This anatomical study of the ninth, tenth, and eleventh intercostal nerves in posterior intercostal space and lateral intercostal space appears to us to allow the realization of a reliable surgical harvesting.
Collapse
|
|
20 |
7 |
24
|
|
News |
30 |
6 |
25
|
|
News |
30 |
6 |