Mexican Multicenter Experience of Metastatic Spinal Disease.

Background Spinal metastatic disease is a silent progressive cancer complication with an increasing prevalence worldwide. The spine is the third most common site where solid tumors metastasize. Complications involved in spinal metastasis include root or spinal cord compression, progressing to a declining quality of life as patient autonomy reduces and pain increases. The main objective of this study is to report the incidence of patients and typology of spinal metastases in three reference centers in Mexico. Methodology Retrospective cohorts of patients diagnosed with spinal metastases from January 2010 to February 2017 at the National Cancer Institute, National Rehabilitation Institute, and the Traumatology and Orthopedics Hospital "Lomas Verdes" in Mexico City were analyzed. Results A total of 326 patients (56% males) with spinal metastases were reported. The mean age was 58.06 ± 14.05 years. The main sources of spinal metastases were tumors of unknown origin in 53 (16.25%) cases, breast cancer in 67 (20.5%) cases, prostate cancer in 59 (18%) cases, myeloma in 24 (7.4%) cases, and lung cancer in 23 (7.1%) cases. Conclusions The data obtained in this analysis delivers an updated standpoint on Mexico, providing the opportunity to distinguish the current data from global references. Collecting more epidemiological information for better recording of cancer and its associated complications, as well as further studies on them, is necessary.

Single Dose of Tranexamic Acid Effectively Reduces Blood Loss in Patients Undergoing Spine Surgery: A Prospective Randomized Controlled Trial.

OBJECTIVE: To evaluate the efficacy of oral administration of tranexamic acid (TXA) in spine surgery to achieve blood loss reduction. METHODS: Sixty patients undergoing major surgery of the spine were randomly assigned into 2 groups. Group 1 was assigned as the control group and the other group comprised patients who received oral administration of TXA 2 hours before surgery. Outcome measures included intraoperative blood loss, postoperative blood loss, hematologic parameters, blood transfusion needed, and surgical complications. RESULTS: Sixty patients linked up with the inclusion criteria. Intraoperative blood loss was significantly lower in the TXA oral group than in the control group; total blood loss in the TXA group was 930.66 ± 614 mL, which was lower than in the control group, with 1075.66 ± 956.11 mL. The mean reduction of hemoglobin was almost the same in both groups. Similarly, the total transfusion package received was lower, and the number of complications and length of stay were akin in both groups. A logistic regression model was performed with patients who had blood loss >1000 mL and surgery time >230 minutes. This result was related to the risk of bleeding, with an odds ratio of 1.31, 95% confidence interval, 1.004-1.023, P = 0.004, independent of the group. CONCLUSIONS: Oral TXA is as an effective measure for reducing total blood loss among patients undergoing elective spine surgery.

Women in Neurosurgery: First Neurosurgeon in Latin America and Current Mexican Leaders.

BACKGROUND: History has taught us that Mexican culture has been largely supported by women, despite gender prejudice from the society. Neurosurgery has not been the exception. Therefore, we investigated the challenges and influence of female neurosurgeons in Mexico. METHODS: We conducted a review of the literature and an analysis of the internal database of the Mexican Society of Neurological Surgery focusing on 3 topics: 1) the historical presence of women and gender inequality in Mexico; 2) the life and legacy of the woman who became the first neurosurgeon in Mexico and in Latin America; and 3) the participation of women in neurosurgery in the past 3 decades. RESULTS: In Latin America, the first woman in neurosurgery was María Cristina García-Sancho, who completed her neurosurgical training in 1951. Currently, women represent 6.2% of the total members of the Mexican Society of Neurological Surgery (MSNS). This percentage is still low, although data collected in this study suggest that it might increase in the next few years because 16.7% of Board Directors of the MSNS are women, the next elected president is a female neurosurgeon, and 14.5% of neurosurgery residents are women. CONCLUSIONS: Although a steady increase has occurred of women in neurosurgery in Mexico, there is still work to do, especially to overcome the barriers related to the old assumptions of the cultural and social roles of women.

Posterior dynamic stabilization of the lumbar spine with the Accuflex rod system as a stand-alone device: experience in 20 patients with 2-year follow-up.

Decompression surgery for lumbar spinal stenosis is a common procedure. After surgery, segmental instability sometimes occurs, therefore, different methods for restabilization have been developed. Dynamic stabilization systems have been designed to improve segmental stability. In this study, clinical results of patients with lumbar spinal stenosis that underwent decompression and stabilization with the Accuflex dynamic system are presented; clinical, radiographic, and magnetic resonance imaging (MRI) findings are fully described. Improvements in all clinical measurements, including visual analog scale for back and leg pain, Oswestry disability index, and SF-36 health status survey were noticed. At a 2-year follow-up, 22.22% of patients required hardware removal due to fatigue while in 83% of them no progression of disk degeneration was observed after implantation of the Accuflex system. Additionally, as demonstrated by the MRI images at follow up, three patients (16%) showed disk rehydration with one grade higher on the Pfirmann classification. Although a relatively high hardware failure was observed (22.22%), the use of the dynamic stabilization system Accuflex posterior to decompression procedures, showed clinical benefits and stopped the degenerative process in 83% the patients.

Tophaceous Gout in the Lumbar Spine Causing Radiculopathy. / Gota tofácea en la columna lumbar causando radiculopatía.

Tophaceous deposits in lumbar spine is considered a rare condition. We report the case of a 44-year-old patient with low back pain and radiculopathy. Radiographs revealed lytic spondylolisthesis in L5. Magnetic resonance imaging showed hypointense signal on T1 and a heterogeneous signal on T2 located in the L4-L5 interspinous space and in the left facet joint that invades left neuroforamen. The left knee ultrasound showed «double contour¼ of the medial femoral condyle. Decompressive laminectomy with arthrodesis at the level of L5-S1 was performed. The histological examination revealed amorphous material with a foreign body giant cell reaction.

Biomechanical behavior of bone tissue in spine instrumentation.

BACKGROUND: The mechanical fixation of the spine in patients with osteoporotic vertebral degeneration is a challenge for surgeons, the vertebrae selected to insert the screws may fail, endangering health and even patient's life. OBJECTIVE: The objective of the study was to study the effect of the variation of the bone density in the bone-screw interface from a three-dimensional model of the lumbar section. MATERIALS AND METHODS: The finite element method was used to model the behavior of the lumbar vertebral section when applying compression loads. RESULTS: The stresses between 2 and 3 MPa were located on the contact surface with the screw, both in the vertebral body and in the apophysis, being slightly higher in the vertebral body. CONCLUSIONS: Regardless of bone density, the contact zones between the screws are susceptible to bone tissue failure. The posterior half of the vertebral body was the most sensitive to high values of stress, while in the areas furthest from the axis of the screw stress tended to their minimum.

INTRODUCCIÓN: La fijación mecánica de la columna en pacientes con degeneración vertebral osteoporótica es un reto para los cirujanos, pues las vértebras seleccionadas para insertar los tornillos pueden fallar, poniendo en peligro la salud y la vida del paciente. OBJETIVO: Estudiar el efecto de la variación de la densidad ósea en la interfase hueso-tornillo, a partir de un modelo tridimensional de la sección lumbar. MATERIALES Y MÉTODOS: Se emplea el método de los elementos finitos para modelar el comportamiento de la sección vertebral lumbar al aplicar cargas de compresión. RESULTADOS: Los esfuerzos entre 2 y 3 MPa se ubicaron en la superficie de contacto con el tornillo, tanto en el cuerpo vertebral como en la apófisis, siendo ligeramente superiores en el cuerpo vertebral. CONCLUSIONES: Independientemente de la densidad ósea, las zonas de contacto entre el tornillo son susceptibles al fallo del tejido óseo, debido a que están próximos al esfuerzo de fallo óseo de 2.37 ± 1.14 MPa reportado en la literatura. La mitad posterior del cuerpo vertebral fue la más sensible a sufrir valores altos de esfuerzos, mientras que en las zonas más alejadas del eje del tornillo los esfuerzos tendieron a su magnitud mínima.

Posterior Grade 4 Osteotomy With Vertebral Shortening Is Effective for the Treatment of Kyphosis Associated With Vertebral Discitis/Osteomyelitis.

BACKGROUND: In the retrospective study of a prospectively maintained database, we present a case series of patients with kyphotic deformity secondary to spinal infection treated using a posterior-only approach with 3-column shortening and posterior instrumentation. METHODS: This is a case series of patients presenting with postural deformity and sagittal imbalance treated consecutively by 1 surgeon between 2012 and 2014. Clinical assessments and radiographic evaluations were made preoperatively and at 12- and 24-month postoperative follow-ups. All patients underwent computed tomography 24 months after surgery to evaluate spinal fusion. RESULTS: The study included 5 patients with a mean age of 50 years (range, 32-60 years). Three patients had comorbidities. Three patients were classified as American Spinal Injury Association (ASIA) grade C and were not ambulatory; 2 were ASIA grade D. At follow-up, all patients were ambulatory and classified as ASIA grade E. Kyphosis was corrected from a preoperative mean of 32° (range, 15°-58°) to 10° (range, 1°-42°) at the 2-year follow-up. A mean improvement of 22° and 75% reduction in kyphosis was obtained with fixation 2 levels above and below the lesion. Interbody fusion was observed in all patients. No major complications occurred during surgery. CONCLUSIONS: Posterior grade 4 osteotomy with vertebral shortening can be performed safely in patients with kyphosis associated with vertebral discitis/osteomyelitis in the thoracolumbar region. The single approach allowed the surgeon to debride the infection, correct the kyphosis, decompress the spinal canal, and stabilize the spine. LEVEL OF EVIDENCE: 4.

Characteristics of Spinopelvic Sagittal Alignment in Lumbar Degenerative Disease.

BACKGROUND: Normal sagittal alignment shows a range of variations and normal values. This study compared sagittal vertebral alignment in patients with different degenerative lumbar diseases. METHODS: This cross-sectional study evaluated 300 patients who were enrolled between June 2016 and June 2017. Of these patients, 213 met the study criteria and were included. RESULTS: Of the 213 patients, 66 were men (31%) and 147 were women (68.2%). The mean age was 62.7 years. Diagnoses included degenerative spondylolisthesis in 116 patients (52.7%), lumbar disk degeneration in 76 patients (34.5%), lumbar spinal stenosis in 19 patients (8.6%), and lytic spondylolisthesis in 7 patients (3.2%). The most frequent Roussouly type of sagittal alignment was type 3 (33.6%), followed by type 4 (25.9%). No significant correlation was associated with Roussouly type of sagittal alignment and lumbar degenerative disease. Median sagittal vertebral alignment parameters in the series were as follows: pelvic incidence (PI), 60.55° ± 15.62°; sacral slope, 39.09° ± 12.48°; pelvic tilt, 20.92° ± 8.99°; lumbar lordosis, 33.15° ± 18.49°; and sagittal balance, 19.64 ± 55.27 mm. One hundred sixteen patients with degenerative spondylolisthesis had significant greater PI than those with other diagnoses (61.56° vs. 58.3°, respectively; P = 0.005), and patients with lumbar spinal stenosis had significantly lower PI than those with other diagnoses (55.89° vs. 60.44°, respectively; P = 0.005). CONCLUSIONS: Pelvic incidence may play a predisposing role in the pathogenesis of lumbar degenerative disease. Patients with degenerative spondylolisthesis have greater pelvic incidence with increased lumbar lordosis. In contrast, patients with spinal stenosis have lower pelvic incidence with flatter lumbar lordosis.

[Failed back surgery syndrome]. / Síndrome de columna multioperada.

BACKGROUND: Failed back surgery syndrome (FBSS) is well known and physicians often fear this outcome. Its definition is difficult to understand because it is multifactorial. However, we analyze its etiology in order to determine if it is from iatrogenic causes. This syndrome can be categorized as follows: mistaken diagnoses, transoperative error, technique error, poor application, poor indication. METHODS: We undertook a prospective, observational and lineal study in 20 patients, 313 surgeries and 4,500 consultations. Age and gender variables were analyzed, number of prior surgeries, and diagnosis prior to first surgery, as well as predominant symptoms for the last surgery, surgical time, and involved segment. Patients were evaluated with Oswestry preoperative scale and followed up for 2 years. RESULTS: There were 16 females and 4 males with an average age of 53.2 years. Eight patients had 1 prior surgery, 8 patients had 2 prior surgeries, 3 patients had 3 prior surgeries, and 1 patient had 4 prior surgeries. According to the Oswestry preoperative scale, 12 patients had scores higher than 60% and at 2-year follow-up, 11 patients had scores lower than 20%. Despite the persistent symptomatology and complications, in almost all patients the satisfaction index was 100%. According to the evaluation, the main cause was poor indication in three patients, poor indication + technique error in 10, and technique error in 7 patients. CONCLUSIONS: The most reported initial etiology was lumbar disc hernia with minimally invasive treatment with questionable surgical indication.

[Experience with prosthetic disc nucleus device in Mexico. Final report of a 4-year follow-up]. / Experiencia en México con prótesis discal de núcleo. Reporte final a 4 años de seguimiento.

BACKGROUND: Discal hernia is generally treated by discectomies that are mutilating and cause instability and low back pain in 50% of the patients. Partial arthroplasty is used in an attempt to avoid degeneration after a discectomy. METHODS: Nineteen patients from the INR (National Institute of Rehabilitation) were selected with extruded discal hernia. All inclusion criteria were met, with a minimal follow-up of 4 years. Evolution was evaluated with the Oswestry scale (OS) and x-ray studies. Statistical analysis was done with Student's t-test. RESULTS: Sixteen men and three women were included in the study, with an average age of 35.4 years. OS before surgery was 57.37% and improved to 22% (p < 0.001). The results obtained in the Prolo scale 4 years later were for the economy scale, p < 0.001 (Wilcoxon Z = 3.87) and for the functional scale, p < 0.001 (Wilcoxon Z = -3.94). The intervertebral space height (IS) before surgery was 6 and 8 mm, and 4 years later, in 12 patients it remained between 8 and 10 mm. The prosthesis had variations according to its initial placement in seven patients, and in all there was subsidence. In two cases migration surpassed the limits of the vertebral body without clinical repercussion. None of the patients required re-operation. CONCLUSIONS: Prosthetic disc nucleus device improved clinical conditions and x-rays of the patients using Oswestry, Prolo and intersomatic space height enhancement after 4 years of follow-up in 12/19 patients.

[Surgical treatment for scoliosis. Minimal evolution control at 5 years]. / Tratamiento quirúrgico de la escoliosis. Control de evolución mínimo de 5 años.

BACKGROUND: We undertook this study to determine the surgical treatments results performed often to correct scoliosis in the Spinal Surgery Service in the INR/Orthopedics (National Institute of Rehabilitation/Orthopedics), Mexico City. METHODS: We conducted a longitudinal, prospective, descriptive, and clinical study with a deliberated intervention controlled from a historical cohort. One hundred twenty patients with scoliosis were reviewed in whom surgery was performed during 1990-1999. For quantitative variables, pre- vs. postoperative measures were compared using non-parametric means with chi(2) or in this case with ANOVA by Kruskall-Wallis test. Differences are considered significant if p <0.05. RESULTS: Age average of patients was 12 years. There were 75 females and 45 males. There were 59 idiopathic scoliosis cases and 54 congenital scoliosis cases. Anterior approach was accomplished in 61 cases with posterior fixation. Posterior approach was used in 54 cases. There were 76 cases of Luque segmental instrumentation. Pre-operatively, scoliosis was ranked (18 to 110 grades) and postoperatively (5 to 90 grades) (p = 0.00001). There were 21 complications, 9 due to injuries or infection. In 76 patients, different fixation techniques were used, obtaining a correction average of 14.47 grades. Forty four patients were structured with bars, four distal screws, two compression screws, proximal hooks with sublaminar wire, and the angle was reduced on average 23.11 grades. CONCLUSIONS. Average reduction of scoliosis was higher with the modified Luque III instrumentation (p <0.045). There was no difference between etiology and preoperative angle.

[Percutaneous biopsy evaluation in the diagnosis of thoracic and lumbar vertebral destruction syndrome]. / Evaluación de la biopsia percutánea en el diagnóstico del síndrome de destrucción vertebral tóracico y lumbar.

BACKGROUND: The vertebral destruction syndrome is defined as those pathologies affecting the integrity of the vertebral structure, modifying its normal architecture and resulting in neurological deficit. Correct diagnosis is essential to define appropriate treatment. Biopsy, in addition to histopathological study, is a vital element for definitive diagnosis. METHODS: We carried out a descriptive, deliberate interventional study in 20 patients with a diagnosis of vertebral destruction in whom a percutaneous transpendicular biopsy was done between January 2005 and July 2006. Variables analyzed were age, sex, affected segment, neurological condition, neurological deficit type, results of the biopsy and specific diagnosis. RESULTS: There was a predominance of males (55%). The lumbar spine was the most affected region in 80% of patients. Of the biopsies performed, 10% were reported as normal tissue, 20% with degenerative changes, 15% with inflammatory changes, 15% with primary tumoral lesion, 5% with chronic osteomyelitis, 10% with tuberculosis, 15% with tumoral metastasis and 10% necrotic devitalized bone tissue. Of these patients, 55% were treated nonsurgically, and the remaining 45% were treated surgically. No complications were reported. CONCLUSIONS: Percutaneous transpedicular biopsy has only 55% specificity in diagnosis and for that reason is a less useful diagnostic method in our setting for destructive lesion diagnosis from the vertebral body.

[Results to 4-year follow-up of the treatment of the cervical stenosis by corpectomy, titanium mesh cage and anterior plate fixation]. / Resultados a 4 años de seguimiento del tratamiento del conducto cervical estrecho mediante corpectomía, malla de titanio y fijación anterior con placa.

BACKGROUND: Cervical spondylotic myelopathy is caused by cervical stenosis. Several techniques have been described for the treatment of multilevel disease, such as the anterior corpectomy with titanium mesh cage and anterior cervical plate placement, which has the advantage of performing a wider decompression and using the same bone as graft. However, it has caused controversy since the collapse of the mesh cage continues being a major limitation of this procedure. MATERIAL AND METHOD: A prospective 4-year follow-up study was conducted in 7 patients diagnosed with cervical stenosis, who were treated surgically by one level corpectomy with titanium mesh cage and anterior cervical plate placement, evaluating them by radiographs and clinical scales. RESULTS: 7 patients, 5 women and 2 males were studied. The most common level was C5 corpectomy (n=4). The Neck Disability Index (NDI) preoperative average was 30.01±24.32 and 4-year postoperative 16.90±32.05, with p=0.801. The preoperative and 4-year postoperative Nürick was 3.28± 48 and 3.14±1.21 respectively, with p=0.766. Preoperative lordosis was 14.42±8.03 and 4-year postoperative 17±11.67 degrees, with p=0.660. The immediate postoperative and 4-year postoperative subsidence was 2.69±2.8 and 6.11±1.61 millimeters respectively, with p=0.0001. CONCLUSIONS: Despite the small sample, the subsidence of the mesh cage is common in this procedure. No statistically significant changes were observed in the lordosis or Nürick scale and NDI.

[Aneurysmal bone cyst of the spine. Case report]. / Quiste óseo aneurismático de la columna vertebral. Reporte de un caso.

The aneurysmal bone cyst (ABC) is a fast-growing tumor of undefined neoplastic nature. It is occasionally an aggressive benign lesion whose treatment of choice is a complete resection, even though the risk of profuse transoperative bleeding exists. We present a female patient with thoracic spine deformity, with progressive paresthesias and muscle weakness of lower extremities that evolved to paralysis of both lower extremities and sphincter incontinence. Based on radiographic films, lytic lesions were identified at T7 to T9 vertebrae as well as medullary space invasion. In electrophysiologic tests, a complete somatosensorial pathway block was reported. Prior to resection of the neoplastic lesion and thoracolumbar stabilization, an incisional biopsy was performed. There was no postoperative medullary functional improvement. Morphological findings corresponded to an aneurysmal bone cyst at T8. This lesion is mainly located in the long bones and less frequently of the spine, where instability and medullary compression may occur. It is possible to confuse this neoplasia with other lesions. Hence, definite diagnosis with biopsy is necessary for determining an adequate therapeutic plan to eradicate recurrence risk or associated neurologic sequelae, as well as to gain proper stability at the involved vertebral segments.

[Stability effect of the suprajacent vertebrae after fixation in spondylolisthesis. Comparative study of two systems]. / Repercusión en la estabilidad del segmento suprayacente después de la fijación de la espondilolistesis. Estudio comparativo de dos sistemas.

BACKGROUND: This study was undertaken to evaluate vertebral stability after two different types of fusion fixation (rigid and semirigid) in spondylolisthesis. MATERIAL AND METHODS: Ambispective study of a dynamic cohort constituted by 42 patients that underwent surgery between 1990 and 2000 for a spondilolistesis treatment. According to the fixing type, they were divided into two follow-up groups: to group 1, plate INO (semirigid system) was placed + posterolateral fusion (PLF), 20 cases; to group 2, plate INO was installed + intersomatic screw + PLF, 22 cases. RESULTS: Both groups achieved better listhesis, reduced pain according to Oswestry and SF36 Index (p <0.05), and less intervertebral height was lost. Group 1 lost the least amount (-0.61 mm) of invertebral height if grades of presurgical listhesis were 1-2, and higher (-2.0 mm) if grades of presurgical listhesis were 3-4. Inversely, group 2 lost the least (0.50 mm) if grade of listhesis was 3 or 4, and higher (-1.25 mm) if grades of listhesis were 1-2. From 4 to 7 years, in group 2 there was altered bending of 5.8 degrees to 8.3 degrees (p = 0.05), a significant difference from group 1. Group 2 showed higher flexion grades (p = 0.01) at 4-7 years postoperatively and a significant reduction in EVA (p = 0.04) at more than 7 years. The remaining patients showed no significant differences between groups. But loss of intervertebral height was higher in group 2 (-1.18 mm) than group 1 (-0.75 mm). Plate INO + PLF favored flexibility and reduced loss of intervertebral height in grades 1-2 of presurgical listhesis, INO + screw + PLF showed reduced listhesis and decrease of height lost in grades 3-4 of presurgical listhesis. CONCLUSIONS: We recommended the use of INO + PLF in grades 1-2 of presurgical listhesis and INO + screw + PLF in grades 3-4 of listhesis presurgically.

Hybrid Decompression and Fixation Technique for the Treatment of Multisegmental Cervical Spondylotic Myelopathy.

BACKGROUND: Cervical spondilotic myelopathy (CSM) is defined as the compromise of the spinal cord due to degenerative changes of the cervical spine. It is the most common cause of spinal cord dysfunction in patients over 55 years. An early surgical management it is paramount to achieve better neurological outcome. There is still controversy regarding the appropriate surgical treatment for multisegmental CSM involving three or more levels. The hybrid decompression and fixation technique combines one or two level corpectomy and a single level discectomy in order to obtain optimum decompression and fixation in patients with multilevel cervical myelopathy. METHODS: A prospective case-control study was made between 2011 and 2013. A total of 15 patients with diagnosis of CSM received surgical treatment with an anterior hybrid decompression and fixation technique procedure. Inclusion criteria were myelopathy confirmed by radiographic studies, magnetic resonance image (MRI) and electromyography. RESULTS: During the 2010-2013 period 15 patients were managed by hybrid decompression and fixation technique. Average age 64.8 years SD9.4. The follow up period was 29.6 SD ± 9.8 months. The JOA score improved significantly to 13.8 +/- 1.9 points at follow-up (paired t test, P = 0.001), Nurick Scale preoperative was 3.3 and improved to 2.4 mean, was significantly (Wilcoxon signed rank test p=0.006) The mean C2-C7 lordosis angle was 10.8° +/- 8.9 before surgery, and 14.3° +/- 8.8 at follow-up, there was no significant loss of lordosis angle between the preoperative and follow-up measurements (Wilcoxon signed rank test, P =0.149); At follow-up, graft non fusion was seen in 1 patient (7%, k=1). CONCLUSIONS: In this small number, single surgeon, prospective series the use of a single level corpectomy and an adjacent discectomy was shown to provide similar outcomes and complication rates as alternative surgical techniques. The authors thus consider this a viable surgical alternative with some perceived advantages, a low rate of complications and a high rate of spinal fusion. Level of Evidence: IV. This study was approved by the authors' Institutional Review Board and all patients were given informed consent prior to participation in the study.

3D patient-specific model of the tibia from CT for orthopedic use.

OBJECTIVES: 3D patient-specific model of the tibia is used to determine the torque needed to initialize the tibial torsion correction. METHODS: The finite elements method is used in the biomechanical modeling of tibia. The geometric model of the tibia is obtained from CT images. The tibia is modeled as an anisotropic material with non-homogeneous mechanical properties. CONCLUSIONS: The maximum stress is located in the shaft of tibia diaphysis. With both meshes are obtained similar results of stresses and displacements. For this patient-specific model, the torque must be greater than 30 Nm to initialize the correction of tibial torsion deformity.

[Profile of the patient with failed back surgery syndrome in the National Institute of Rehabilitation. Comparative analysis]. / Perfil del paciente con síndrome de columna multioperada en el Instituto Nacional de Rehabilitación. Análisis comparativo.

BACKGROUND: Failed back surgery syndrome is a complication of spine surgery that leads to chronic pain and disability, often with disastrous emotional consequences to the patient. AIM: To compare the profile of patients whose first surgery was performed in our hospital versus a group that underwent first spine surgery in a different centre. METHODS: Retrospective study with 65 patients; 18 formed group I (first spine surgery performed in our institution), and 47 patients in group II (first surgery performed in another hospital). Background, demographic, clinical features and functional status were compared. In group I the majority of the cases had a previous diagnosis of lumbar stenosis (group I 44.4% vs group II 25.5% p = 0.22), whereas disk herniation was the main diagnosis in group II (group I 22.2% vs group II 61.7% p = 0.001). The main cause of the syndrome in group I was technical error during surgery (61.1%), while in group II this cause represented only 6.3% (p=.001). Among the patients of this latter group, misdiagnosis was highly prevalent (57.4%), against no cases in group I (p=.001). The preoperative functional status between both groups and their recovery in the immediate postoperative period was similar (p = 0.68). CONCLUSIONS: This study suggests that the diagnostic and treatment standards are different between healthcare centres, specifically between academic centres vs. private practice.

[Transpedicular dynamics stabilization in the treatment of lumbar stenosis. Fourth years follow-up]. / Estabilización dinámica transpedicular en el tratamiento del conducto lumbar estrecho. Seguimiento cuatro años.

INTRODUCTION: We need to evaluate the efficacy and safety of the use of dynamic fixation in patients with narrow lumbar through comparing the assessment of two years with 4 years of follow-up. METHODS: Prospective, longitudinal, autocontrol deliberately and sequential intervention, in lumbar stenosis patients who made treatment with dynamic stabilization posterior type Acuflex. An evaluation of four of final follow-up. RESULTS: 18 patients who completed follow-up two years results as a basis for comparison: 18 patients, 14 female and 4 male, average age 44.05 years. Pain evaluated with numerical visual scale was found in the lower back at 24 months in an average of 2.84 and 48 months in 3.26. We measured the functional level of Oswestry at two years to be 24% and at four years 22.44%, with a p = 0.373. In the magnetic resonance for classification of patients 15 Pfirrmann without changes and three with increase of a degree. According to patients 2 Modic changes one of type 0 to type III and another to type I. We have observed that five patients have required second surgery for removal of material findings. CONCLUSIONS: There is no change between 2 and 4 years in the scale of Oswestry and pain with visual numerical scale functionality. The average height in discs had change with statistical significance, in the comparative period. The intervertebral discs had changes in 3 patients with direct relationship between scale of Pfirrmann and Modic. The rest of patients keep rehydration and normal disc height.

[Use of the PEEK cage in cervical spondylosis treatment]. / Uso de caja de PEEK (Poli-ether-ether-ketona) parael tratamiento de la espondilosis cervical.

BACKGROUND: Decompression and fusion with autograft is the gold standard technique in the treatment of cervical canal strait. Using PEEK cages or boxes of non-absorbable polymer with elasticity similar to bone, radiolucent, reduces morbidity and same degree of fusion. METHODS: A case series, prospective, longitudinal, deliberate intervention, evaluation panel before and after 2 years follow-up. Discectomy and PEEK housing placement with autologous graft. Arthrodesis were evaluated, cervical lordosis, intervertebral space height, pain evaluated with Visual Analogue Scale, Neck Disability Index, operative time, intraoperative bleeding, hospital stay and complications. Statistical analysis with t Sudent, Wilcoxon and Fisher's exact text. RESULTS: Of 17 patients studied, 9 (53%) were female. Average age 62 years. The most affected level was C5-6, C6-7 with 5 patients. Melting was found at 100%. There was no sag or migration of the box, space height was conserved, but segmental lordosis was not retained. Clinical improvement in all patients as well as disability index was seen. Bleeding was on average 187 mL. CONCLUSION: With regard to symptom improvement, conservation of interspace height and back, no segmental lordosis conservation and fusion using PEEK box is consistent with the literature. We suggest using anterior plate to maintain cervical lordosis. We found a melt index of 100%. We found clinical improvement of symptoms, pain and disability, and a global loss of cervical lordosis.

Antecedentes: la descompresión y artrodesis con auto-injerto es el patrón de referencia para el tratamiento del conducto cervical estrecho. El uso de cajas de PEEK polímero no reabsorbible, con elasticidad similar al hueso, radiolúcido, y mismo grado de fusión reduce la morbilidad. aterial y métodos: estudio de serie de casos, prospectivo, longitudinal, de intervención deliberada, evaluación en grupol antes y después, seguimiento a dos años. Discoidectomía y colocación de caja de PEEK con injerto autólogo. Se evaluaron artrodesis, lordosis cervical, altura del espacio intervertebral, dolor mediante escala visual análoga, índice de discapacidad cervical, tiempo quirúrgico, sangrado transoperatorio, estancia intrahospitalaria y complicaciones. Análisis estadístico con t de Student, Wilcoxon y exacta de Fisher. Resultados: de 17 pacientes estudiados, 9 (53%) eran del sexo femenino. La edad promedio 62 años. Sangrado promedio de 187 mL. El nivel más afectado fue C5-C6, C6-C7 en cinco pacientes. Se encontró fusión al 100% sin hundimiento ni migración de la caja, altura del espacio conservada, pero no se conservó la lordosis segmentaria. Mejoría clínica en todos los pacientes, y del índice de discapacidad. Conclusión: la disminución de los síntomas, la conservación de la altura del espacio anterior y posterior, la no conservación de la lordosis segmentaria y la fusión con caja de PEEK fueron congruentes con lo reportado en la bibliografía. Se sugiere utilizar la placa anterior para mantener la lordosis cervical. El índice de fusión encontrado fue de 100%, con disminución de los síntomas de dolor y discapacidad. Pérdida de lordosis cervical global.