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1.
Eur Spine J ; 29(8): 1925-1934, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32451777

RESUMO

BACKGROUND: Damaged or degenerated vertebral endplates are a significant cause of vertebrogenic chronic low back pain (CLBP). Modic changes are one objective MRI biomarker for these patients. Prior data from the treatment arm of a sham-controlled, RCT showed maintenance of clinical improvements at 2 years following ablation of the basivertebral nerve (BVN). This study reports 5-year clinical outcomes. METHODS: In total, 117 US patients were treated successfully with BVN ablation. Patient-reported outcomes of ODI, VAS, postablation treatments, and patient satisfaction were collected at a minimum of 5-years following BVN ablation. Primary outcome was mean change in ODI. Comparisons between the postablation and baseline values were made using an analysis of covariance with alpha 0.05. RESULTS: Of the 117 US treated patients 100 (85%) were available for review with a mean follow-up of 6.4 years (5.4-7.8 years). Mean ODI score improved from 42.81 to 16.86 at 5-year follow-up, a reduction of 25.95 points (p < 0.001). Mean reduction in VAS pain score was 4.38 points (baseline of 6.74, p < 0.001). In total, 66% of patients reported a > 50% reduction in pain, 47% reported a > 75% reduction in pain, and 34% of patients reported complete pain resolution. Composite responder rate using thresholds of ≥ 15-point ODI and ≥ 2-point VAS for function and pain at 5 years was 75%. CONCLUSION: CLBP patients treated with BVN ablation exhibit sustained clinical improvements in function and pain with high responder rates at a mean of 6.4 years following treatment. BVN ablation is a durable, minimally invasive treatment for vertebrogenic CLBP.


Assuntos
Dor Crônica , Dor Lombar , Dor Crônica/cirurgia , Método Duplo-Cego , Humanos , Dor Lombar/cirurgia , Medidas de Resultados Relatados pelo Paciente , Estudos Prospectivos , Resultado do Tratamento
2.
Heliyon ; 9(3): e13404, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36789384

RESUMO

The COVID-19 pandemic has forced many conferences and educational events to shift from in-person to online, significantly reducing the carbon footprint associated with these activities. Workshops are a common pattern of thematic learning at the university level, usually involving a series of activities, such as gathering, learning, and dining, for participants from different regions. However, unlike a three-day conference, workshops usually last for seven days or more, resulting in a non-negligible carbon footprint. To resolve this challenge, we have developed a model that provides recommendations for minimizing the carbon footprint of workshops. Using data from the DigitalFUTURES International Workshop on architecture education at Tongji University in China, we calculated the carbon footprint of scenarios with varying workshop durations, participation modes, and transportation methods. Our results show that online workshops can reduce the carbon footprint by up to 88% compared to in-person workshops. Hybrid workshops, which combine online and in-person participation, can also lead to significant carbon reductions, with a 46% online participation rate resulting in an 82% reduction in carbon footprint. However, we recommend that in-person participation be maintained to ensure efficient learning and effective communication. Our work provides a sustainable solution for organizing future workshops with a reduced carbon footprint.

3.
Med Devices (Auckl) ; 14: 211-216, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34234582

RESUMO

BACKGROUND: Strong evidence supports minimally invasive sacroiliac joint (SIJ) fusion using triangular titanium implants (TTI) for chronic SIJ dysfunction. OBJECTIVE: To report safety and effectiveness of SIJF using a 3D-printed TTI at 24 months. METHODS: SIJF with TTI was performed in 51 subjects. Structured follow-up occurred at 3, 6, 12 and 24 months. Both quality of life questionnaires and functional tests were performed at all study visits. RESULTS: 84% of subjects were available for 24-month follow-up. Observed were rapid and persistent improvements in dysfunction due to pain (Oswestry Disability Index [ODI], mean 52.8 at baseline and 28.3 at 24 months, p<0.0001) and SIJ pain ratings (mean 78.5 at baseline [0-100 scale] to 21.5 at 24 months). Opioid use for SIJ pain decreased markedly from baseline. Physical function tests impaired by SIJ pain showed persistent improvements compared to baseline. There was no evidence of device breakage, migration or subsidence and few late adverse events occurred attributable to the device. CONCLUSION: In this prospective study, SIJF using 3D-printed TTI resulted in immediate, marked and persistent improvements in pain and quality of life, with improved physical function, reduced opioid use and a low rate of late device-related adverse events. LEVEL OF EVIDENCE: Level II.

4.
Med Devices (Auckl) ; 13: 173-182, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32607011

RESUMO

BACKGROUND: Prior trials provide strong evidence supporting minimally invasive sacroiliac joint (SIJ) fusion using triangular titanium implants (TTI) for chronic SIJ dysfunction. OBJECTIVE: To assess the safety and effectiveness of SIJF using a 3D-printed TTI. METHODS: Fifty-one subjects with carefully diagnosed SIJ dysfunction underwent SIJF with 3D TTI. Subjects completed pain, disability and quality of life questionnaires at baseline and 3, 6 and 12 months postoperatively. Functional tests were performed in the clinic at each visit. Pelvic CT scans were independently evaluated for radiolucency, bridging bone and other endpoints. RESULTS: Ninety percent had 12-month follow-up. Dysfunction due to pain (Oswestry Disability Index [ODI]) decreased from 52.8 at baseline to 27.9 at 12 months (p<.0001 for change, p=.004 for non-inferiority primary hypothesis). SIJ pain scores improved from 78 preoperatively to 21 at 12-month follow-up (P<.0001). Ninety-six percent experienced an improvement of 20 points or more in VAS SIJ pain by month 12. The percentage of subjects reporting minimal difficulty performing physical activities typically impaired by back/SIJ pain improved significantly for all activities. The proportion of subjects taking opioids for SIJ pain decreased from 57% to 22%. Three physical function tests improved markedly from baseline to 1 year. Positive radiographic findings were observed, including a 70% and 77% rate of bone bridging observed at 6 and 12 months, respectively. There was no evidence of device breakage, migration or subsidence. CONCLUSION: In this prospective multicenter trial, SIJF with 3D-printed TTI markedly improved pain, disability and quality of life. Results are consistent with 3 prior prospective multicenter trials of a milled implant but suggest accelerated bony fusion with the newer implant. Physical function improved, and high rates of opioid cessation were observed. LEVEL OF EVIDENCE: Level II.

5.
Med Devices (Auckl) ; 12: 203-214, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31239791

RESUMO

Background: Minimally invasive sacroiliac joint (SIJ) fusion (SIJF) has become an increasingly accepted surgical option for chronic SI joint dysfunction, a prevalent cause of chronic low back/buttock pain. Objective: To report clinical and functional outcomes of SIJF using 3D-printed triangular titanium implants (TTI) for patients with chronic SI joint dysfunction. Methods: A total of 28 subjects with SIJ dysfunction at 8 centers underwent SIJF with 3D TTI and had scheduled follow-up to 6 months (NCT03122899). Results: Mean preoperative SIJ pain score was 79.1 and mean preoperative Oswestry Disability Index (ODI) was 49.9. At 6 months, pain scores decreased by 51 points and ODI decreased by 23.6 points (both p<0.0001). The proportion of subjects able to perform various back/pelvis-related physical functions with minimal difficulty improved significantly for nearly all activities. Opioid use decreased and physical function, as assessed with three objective tests, improved. Conclusion: Early results from this prospective multicenter trial confirm that clinical responses to a 3D triangular titanium implant for SIJF are similar to those from prior trials, with improved physical function and decreased opioid use. Level of evidence: Level II.

6.
Int J Spine Surg ; 13(2): 110-119, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31131209

RESUMO

BACKGROUND: The purpose of the present study is to report the 2-year clinical outcomes for chronic low back pain (CLBP) patients treated with radiofrequency (RF) ablation of the basivertebral nerve (BVN) in a randomized controlled trial that previously reported 1-year follow up. METHODS: A total of 147 patients were treated with RF ablation of the BVN in a randomized controlled trial designed to demonstrate safety and efficacy as part of a Food and Drug Administration-Investigational Device Exemption trial. Evaluations, including patient self-assessments, physical and neurological examinations, and safety assessments, were performed at 2 and 6 weeks, and 3, 6, 12, 18, and 24 months postoperatively. Participants randomized to the sham control arm were allowed to cross to RF ablation at 12 months. Due to a high rate of crossover, RF ablation treated participants acted as their own control in a comparison to baseline for the 24-month outcomes. RESULTS: Clinical improvements in the Oswestry Disability Index (ODI), Visual Analog Scale (VAS), and the Medical Outcomes Trust Short-Form Health Survey Physical Component Summary were statistically significant compared to baseline at all follow-up time points through 2 years. The mean percent improvements in ODI and VAS compared to baseline at 2 years were 53.7 and 52.9%, respectively. Responder rates for ODI and VAS were also maintained through 2 years with patients showing clinically meaningful improvements in both: ODI ≥ 10-point improvement in 76.4% of patients and ODI ≥ 20-point improvement in 57.5%; VAS ≥ 1.5 cm improvement in 70.2% of patients. CONCLUSIONS: Patients treated with RF ablation of the BVN for CLBP exhibited sustained clinical benefits in ODI and VAS and maintained high responder rates at 2 years following treatment. Basivertebral nerve ablation appears to be a durable, minimally invasive treatment for the relief of CLBP.

7.
Int J Spine Surg ; 12(5): 582-586, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30364829

RESUMO

BACKGROUND: Performing an adequate transforaminal lumbar interbody fusion (TLIF) discectomy requires numerous instrument passes, increasing surgical time and the risk of complications. The purpose of this study was to evaluate the efficacy and efficiency of discectomy and endplate preparation during TLIF using traditional manual instrumentation versus a novel suction discectomy curette. The direct economic benefit with use of the suction discectomy curette is calculated. METHODS: Three experienced, spine-fellowship-trained surgeons performed TLIF discectomies on 3 cadaveric specimens from T12 to S1 using either traditional manual discectomy instruments or CONCORD Clear (Xtool) devices supplemented with manual discectomy instruments. For each level in which a discectomy was performed, the following were measured: elapsed time, number of instrument passes and the number of instrument exchanges, and estimated tissue volume. RESULTS: Transforaminal lumbar interbody fusion discectomy times improved on average 11:32 minutes per level, which equates to an estimated procedural time savings of 15:85 minutes, using 1.4 levels per TLIF, the average number of levels in a large series. Usage of the CONCORD Clear significantly reduced instrument passes compared to traditional, with a mean of 62.0 for traditional versus 7.1 for CONCORD Clear, an 8.7-fold improvement. Instrument exchanges showed a 5.9-fold improvement, with means of 26.8 and 4.6, respectively. Wet discectomy tissue volume was measured for each discectomy, with a mean of 5.4 cc for traditional versus 12.9 cc for CONCORD Clear, a 2.4-fold improvement. CONCLUSIONS: This study estimates that, in a typical TLIF procedure, over 15 minutes should be saved by using the CONCORD Clear l device (a quarter of the time of a traditional discectomy), and by considering the direct cost-benefit associated with this time savings as well as reduced sterilization costs, it is estimated that a hospital could save approximately $1300 in operating room time and sterilization cost with the use of the CONCORD Clear device in a typical 1-level TLIF procedure.

8.
Spine J ; 5(6 Suppl): 317S-324S, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16291129

RESUMO

Debilitating low back pain as a result of symptomatic lumbar disc degeneration places a significant burden on an industrial society. Traditionally surgical treatment involving fusion of the anterior and posterior spinal elements has resulted in unpredictable and frequently irreproducible results, especially with regard to return to work rates. A new surgical method of managing symptomatic disc degeneration recalcitrant to nonoperative measures involves the partial or complete removal of the intervertebral disc with replacement with a motion-sparing device. A review of the English-speaking literature will be discussed evaluating the historical development, design considerations, animal models, basic science studies, cadaveric research, and clinical outcomes of the partial removal of the intervertebral disc (nucleus pulposus) and replacement with a motion-sparing implant. An overview of traditional methods of surgical management of lumbar degenerative disc disease will then be followed by an introduction to the concept of motion-sparing implants (nucleus pulposus replacement) intended to remove the pain generator without the associated morbidity of a surgical fusion.


Assuntos
Deslocamento do Disco Intervertebral/patologia , Deslocamento do Disco Intervertebral/cirurgia , Vértebras Lombares/patologia , Próteses e Implantes , Materiais Biocompatíveis/farmacologia , Discotomia/métodos , Feminino , Seguimentos , Humanos , Dor Lombar/etiologia , Dor Lombar/terapia , Vértebras Lombares/cirurgia , Masculino , Medição da Dor , Desenho de Prótese , Fatores de Risco , Resultado do Tratamento
9.
Instr Course Lect ; 54: 303-12, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15948458

RESUMO

The symptoms associated with lumbar spinal stenosis can decrease quality of life and may cause patients to seek treatment. Except in rare cases of rapid neurologic progression or cauda equina syndrome, nonsurgical modalities should be the initial treatment choice. Activity modification, a variety of medications, epidural steroid injections, and other methods are recommended for pain reduction. A formal physical therapy program, which focuses on flexion-based exercises, may lead to improved patientfunction. Surgery is indicated in patients who remain symptomatic despite a course of nonsurgical therapy and who have advanced imaging studies that correspond to existing .symptoms. Adequate decompression of the neural elements and maintenance of bony stability are necessary for a good surgical outcome for patients with spinal stenosis. Laminectomy has long been the method of choice for thorough lumbar decompression. Preserving at least the lateral half of the facet joints bilaterally and bone in the area of the pars interarticularis minimizes the potential for iatrogenic instability. Numerous other decompression techniques have been described, including multilevel laminotomies, fenestration, distraction laminoplasty, and microscopic decompression. Arthrodesis, either with or without instrumentation, is also indicated in some patients. Several studies report that surgical treatment produces better outcomes than nonsurgical treatment in the short term; however, the results tend to deteriorate with time. Lumbar decompressive surgery can be complicated by epidural hematoma, deep venous thrombosis, dural tear, infection, nerve root injury, and recurrence of symptoms.


Assuntos
Vértebras Lombares , Estenose Espinal/terapia , Descompressão Cirúrgica/métodos , Humanos , Laminectomia/métodos , Estenose Espinal/tratamento farmacológico , Estenose Espinal/cirurgia , Resultado do Tratamento
10.
J Spinal Cord Med ; 28(4): 308-13, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16396380

RESUMO

BACKGROUND: Image guidance provides additional anatomic information to the surgeon, which may allow more accurate insertion of spinal implants. Imprecise placement of anterior thoracic screws places the spinal cord and paraspinal structures at risk for injury. Image guidance may afford a safety benefit to patients when anterior thoracic screws are required in the setting of spinal stabilization after trauma. OBJECTIVES: To compare the accuracy of anterior thoracic screw placement using standard fluoroscopy, computer-assisted fluoroscopic image guidance, Iso-C3D image guidance, and electromagnetic fluoroscopic image guidance. STUDY DESIGN: A surgical simulation study in human cadaver spine specimens. METHODS: After an open thoracotomy approach, anterior thoracic screws were placed by experienced spine surgeons using 4 different image-guided techniques in 4 human cadaver thoracic spines. Screws were placed in the 9th, 10th, and 11th thoracic vertebrae of each specimen. The specimens were then examined with thin-cut computed tomography (CT) scans, and with sagittal and coronal reconstructions. Measurements included the distance of the screw from the spinal canal, the angle of the screw path in relation to a perpendicular to a line that bisects the spinous process, and the angle of screw divergence from the superior endplate. RESULTS: There was no evidence of spinal canal penetrance with any of the image-guided techniques used to place anterior thoracic vertebral body screws. Screws inserted with standard fluoroscopy tended to aim anterolaterally by 18 degrees. The image-guidance systems allowed more accurate placement of anterior thoracic screws in the transverse plane compared with standard fluoroscopy. There was no statistically significant difference in coronal plane screw angulation (angle of divergence with the superior endplate) between any of the imaging methods. CONCLUSIONS: Spinal image-guidance systems may allow spine surgeons to place anterior thoracic screws more precisely, particularly in the axial plane. The improved accuracy of spinal implant insertion could ultimately provide a benefit to patient safety, especially in the setting of malaligned vertebral bodies after trauma.


Assuntos
Parafusos Ósseos , Fixação Interna de Fraturas , Procedimentos Ortopédicos/instrumentação , Traumatismos da Coluna Vertebral/cirurgia , Cirurgia Assistida por Computador/instrumentação , Vértebras Torácicas/cirurgia , Idoso , Cadáver , Segurança de Equipamentos , Fluoroscopia/instrumentação , Fluoroscopia/métodos , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/métodos , Humanos , Pessoa de Meia-Idade , Dispositivos de Fixação Ortopédica , Procedimentos Ortopédicos/métodos , Cirurgia Assistida por Computador/métodos , Toracotomia/instrumentação , Toracotomia/métodos
11.
J Orthop Surg Res ; 9: 20, 2014 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-24666669

RESUMO

BACKGROUND: Minimally invasive lateral approaches to the lumbar spine have been adopted to allow access to the intervertebral disc space while avoiding the complications associated with anterior or posterior approaches. This report describes a minimally invasive technique for lateral lumbar interbody fusion LLIF that allows direct intraoperative visualization of the psoas and surrounding neurovasculature (DV-LIF). METHODS: The technique utilizes a radiolucent tubular retractor and a secondary psoas retractor that allows a muscle-sparing approach while offering excellent visualization of the operative site. The unique advantage of this procedure is that the psoas muscle and surrounding nerves can be directly visualized intraoperatively to supplement neuromonitoring. We retrospectively reviewed complication rates in 34 patients treated with DV-LLIF (n = 19) or standard lateral lumbar interbody fusion (S-LLIF, n = 15). RESULTS: There were 29 complications (median: 1 per patient) with DV-LLIF and 20 (median: 1 per patient) complications with S-LLIF. Postoperative sensory deficits were reported in eight (42%) and seven (47%) patients, respectively. Thigh pain or numbness was reported in eight (42%) and five (33%) patients, respectively. The percentage of the overall complications directly attributable to the procedure was 69% with DV-LLIF and 83% with S-LLIF. One severe complication (back pain) was reported in one DV-LLIF patient and four severe complications (severe bleeding, respiratory failure, deep venous thrombosis and gastrointestinal prophylaxis, and nicked renal vein and aborted procedure) were reported in two S-LLIF patients. CONCLUSIONS: Preliminary evidence suggests that minimally invasive lateral interbody fusion with direct psoas visualization may reduce the risk for severe procedural complications.


Assuntos
Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Monitorização Intraoperatória/métodos , Músculos Psoas/diagnóstico por imagem , Músculos Psoas/cirurgia , Fusão Vertebral/métodos , Idoso , Fluoroscopia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
12.
Spine (Phila Pa 1976) ; 31(2): 234-8, 2006 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-16418646

RESUMO

STUDY DESIGN: A surgical simulation study in human cadaver spine specimens was conducted to evaluate the accuracy of 3 different surgical navigation systems compared to standard fluoroscopy in the percutaneous placement of iliosacral screws. OBJECTIVES: To compare the accuracy of percutaneous iliosacral screw placement using standard fluoroscopy, computer-assisted fluoroscopic image guidance, Iso-C3D image guidance (Medtronic Surgical Navigation Technologies, Louisville, CO), and electromagnetic fluoroscopic image guidance. SUMMARY OF BACKGROUND DATA: Conventional percutaneous sacroiliac screw placement has a malposition rate as high as 15%, as reported in the English-speaking literature (Hinsche et al [Clin Orthop Relat Res 2002;395:135-44] and Templeman et al [Clin Orthop Relat Res 1996;329:194-8]). Iso-C3D and computer-assisted image guidance technologies have been proposed to increase this accuracy rate. METHODS: Two iliosacral screws were placed bilaterally (4 screws) in each of 4 cadavers using standard fluoroscopy, computer-assisted fluoroscopic image guidance, Iso-C3D image guidance, and electromagnetic fluoroscopic image guidance. Screw positions were analyzed by computerized tomography after instrumentation and assigned a score based on deviation from ideal screw position. RESULTS: The StealthStation with FluoroNav (Medtronic Surgical Navigation Technologies) appeared to provide the highest accuracy of all guidance techniques. This result was more accurate than standard fluoroscopy. CONCLUSIONS: Computer-assisted fluoroscopy based image navigation appears to be more accurate than standard fluoroscopy in placing these screws. However, errors may occur with all techniques. Further refinement in registration procedures may highly improve the accuracy of percutaneous screw placement in a variety of spinopelvic procedures.


Assuntos
Parafusos Ósseos , Ílio/diagnóstico por imagem , Sacro/diagnóstico por imagem , Cirurgia Assistida por Computador/normas , Idoso , Discotomia Percutânea/instrumentação , Discotomia Percutânea/métodos , Discotomia Percutânea/normas , Fluoroscopia/instrumentação , Fluoroscopia/métodos , Fluoroscopia/normas , Humanos , Ílio/cirurgia , Pessoa de Meia-Idade , Sacro/cirurgia , Cirurgia Assistida por Computador/instrumentação , Cirurgia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos
13.
J Spinal Disord Tech ; 19(1): 22-7, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16462214

RESUMO

OBJECTIVES: Surgical navigation systems have been increasingly studied and applied in the application of spinal instrumentation. Successful disk arthroplasty requires accurate midline and rotational positioning for optimal function and longevity. A surgical simulation study in human cadaver specimens was done to evaluate and compare the accuracy of standard fluoroscopy, computer-assisted fluoroscopic image guidance, and Iso-C3D image guidance in the placement of lumbar intervertebral disk replacements. METHODS: Lumbar intervertebral disk prostheses were placed using three different image guidance techniques in three human cadaver spine specimens at multiple levels. Postinstrumentation accuracy was assessed with thin-cut computed tomography scans. RESULTS: Intervertebral disk replacements placed using the StealthStation with Iso-C3D were more accurately centered than those placed using the StealthStation with FluoroNav and standard fluoroscopy. Intervertebral disk replacements placed with Iso-C3D and FluoroNav had improved rotational divergence compared with standard fluoroscopy. Iso-C3D and FluoroNav had a smaller interprocedure variance than standard fluoroscopy. These results did not approach statistical significance. Relative to both virtual and standard fluoroscopy, use of the StealthStation with Iso-C3D resulted in improved accuracy in centering the lumbar disk prosthesis in the coronal midline. CONCLUSIONS: The StealthStation with FluoroNav appears to be at least equivalent to standard fluoroscopy and may offer improved accuracy with rotational alignment while minimizing radiation exposure to the surgeon. Surgical guidance systems may offer improved accuracy and less interprocedure variation in the placement of intervertebral disk replacements than standard fluoroscopy. Further study regarding surgical navigation systems for intervertebral disk replacement is warranted.


Assuntos
Artroplastia/métodos , Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgia , Próteses e Implantes , Cirurgia Assistida por Computador , Idoso , Idoso de 80 Anos ou mais , Artroplastia/instrumentação , Cadáver , Fluoroscopia , Humanos , Rotação
14.
J Spinal Disord Tech ; 19(4): 237-41, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16778656

RESUMO

OBJECTIVES: Lumbar fusion has been widely used to treat unstable spinal disorders. Methods are evolving from open procedures to less invasive methods to avoid soft tissue trauma. Recently, a soft tissue sparing method to access the axial lumbosacral spine has been developed. It is crucial to determine structures potentially at risk for injury during this fusion technique. The anatomy of the presacral space and safety of the paracoccygeal approach were evaluated through cadaveric dissection and radiographic studies. The objective was to evaluate the safety of a paracoccygeal approach to the axial lumbosacral spine and determine structures that could potentially be injured. METHODS: The paracoccygeal approach was performed on two cadavers, followed by dissection. Distances from the midline trajectory of the approach to surrounding vascular structures were determined. Similar distances were also measured on computed tomography (CT) and magnetic resonance imaging (MRI) of 12 patients, as well as CT images of two additional patients. A "safe zone" was determined using the sagittal length of the presacral space and the distance between the most medial internal iliac vessel on the right and left, respectively. RESULTS: The coronal safe zone averaged 6.9 and 6.0 cm on MRI and CT, respectively. The mean distance from the anterior sacral margin to the rectum at the S3-S4 level was 1.2 and 1.3 cm on MRI and CT, respectively. CONCLUSION: In this study, we defined the "coronal safe zone" within the presacral space. This "safe zone" may guide surgeons when utilizing the percutaneous paracoccygeal approach.


Assuntos
Vértebras Lombares/anatomia & histologia , Vértebras Lombares/cirurgia , Sacro/anatomia & histologia , Sacro/cirurgia , Fusão Vertebral/métodos , Cadáver , Feminino , Humanos , Técnicas In Vitro , Masculino
15.
J Physiol ; 553(Pt 3): 947-57, 2003 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-14514871

RESUMO

Thirty eccentric contractions (ECs) were imposed upon rat dorsiflexors (n = 46) by activating the peroneal nerve and plantarflexing the foot ~40 deg, corresponding to a sarcomere length change over the range 2.27-2.39 microm for the tibialis anterior and 2.52-2.66 microm for the extensor digitorum longus. Animals were allowed to recover for one of 10 time periods ranging from 0.5 to 240 h, at which time muscle contractile properties, immunohistochemical labelling and gene expression were measured. Peak isometric torque dropped significantly by ~40 % from an initial level of 0.0530 +/- 0.0009 Nm to 0.0298 +/- 0.0008 Nm (P < 0.0001) immediately after EC, and then recovered in a linear fashion to control levels 168 h later. Immunohistochemical labelling of cellular proteins revealed a generally asynchronous sequence of events at the cellular level, with the earliest event measured being loss of immunostaining for the intermediate filament protein, desmin. Soon after the first signs of desmin loss, infiltration of inflammatory cells occurred, followed by a transient increase in membrane permeability, manifested as inclusion of plasma fibronectin. The quantitative polymerase chain reaction (QPCR) was used to measure transcript levels of desmin, vimentin, embryonic myosin heavy chain (MHC), myostatin, myoD and myogenin. Compared to control levels, myostatin transcripts were significantly elevated after only 0.5 h, myogenic regulatory factors significantly elevated after 3 h and desmin transcripts were significantly increased 12 h after EC. None of the measured parameters provide a mechanistic explanation for muscle force loss after EC. Future studies are required to investigate whether there is a causal relationship among desmin loss, increased cellular permeability, upregulation of the myoD and desmin genes, and, ultimately, an increase in the desmin content per sarcomere of the muscle.


Assuntos
Músculo Esquelético/fisiologia , Transcrição Gênica/fisiologia , Animais , Primers do DNA , Desmina/genética , Fibronectinas/genética , Complexo Principal de Histocompatibilidade , Masculino , Fibras Musculares Esqueléticas/fisiologia , Músculo Esquelético/citologia , Condicionamento Físico Animal , Reação em Cadeia da Polimerase , Ratos , Ratos Sprague-Dawley , Descanso , Fatores de Tempo , Torque , Vimentina/genética
16.
J Pediatr Orthop ; 24(4): 370-5, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15205617

RESUMO

This study was designed to evaluate the incidence of compartment syndrome (CS) resulting from the treatment of both-bone forearm fractures in children. A retrospective analysis of 285 consecutive children who presented with both-bone forearm fractures was performed. Of 235 closed injuries, 205 were treated with closed reduction and casting; none of these patients developed CS. Thirty of the closed injuries were treated with closed reduction and intramedullary fixation; three of these patients (10%) developed CS. Fifty patients sustained open fractures and were treated with debridement and open reduction with intramedullary pinning; CS developed in three of these patients (6%). The eighty patients treated with intramedullary fixation had an increased incidence of CS compared with the 205 patients treated with closed reduction and casting (P < 0.001). Within the group of patients who had surgery, patients with longer operative times and more use of intraoperative fluoroscopy were at higher risk of developing CS.


Assuntos
Síndromes Compartimentais/etiologia , Fixação Intramedular de Fraturas/efeitos adversos , Fraturas do Rádio/cirurgia , Fraturas da Ulna/cirurgia , Adolescente , Criança , Pré-Escolar , Desbridamento , Feminino , Fraturas Fechadas/cirurgia , Humanos , Masculino , Fatores de Risco
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