[Os odontoideum. Presentation in adult age]. / Os odontoideum. Presentación en edad adulta.

The Os odontoideum is a variable oval or round ossicle with a smooth cortical border, which partially corresponds to the odontoid process, without having continuity with the rest of C2 bone. The multifactorial etiology causes instability and clinically translates into pain and compression data into neural structures. The treatment of choice is surgical and techniques have been developed that focus on preserving the stability of the segment. We present the case of a 23-year-old female patient, who begins to suffer at 8 years of age, refers to moderate to severe cervicalgia, which develops with paresthesias in the left hemisphere and later paresis of the left thoracic limb. Physical examination showed hypoaesthesia of the left hemisphere, as well as paresis of the left thoracic limb. Extension studies demonstrate chronic axonal lesion from C1 to C3, predominantly left, imaging studies showing axial instability and magnetic resonance bulbar compression. The patient receives surgical treatment consisting of posterior fixation C1-C2, evolving satisfactorily.

Os odontoideum es un osículo oval o redondo de tamaño variable con un borde cortical liso, que se corresponde parcialmente con la apófisis odontoides, sin tener continuidad ósea con el resto de C2. La etiología es multifactorial, causa inestabilidad y clínicamente se traduce en dolor y datos de compresión a las estructuras neurales. El tratamiento de elección es quirúrgico y se han desarrollado técnicas que se enfocan en conservar la estabilidad del segmento. Presentamos el caso de una mujer de 23 años, inicia padecimiento a los ocho años, refiere cervicalgia moderada a intensa, que evoluciona con parestesias en hemicuerpo izquierdo y posteriormente paresia de miembro torácico izquierdo. A la exploración física se evidencia hipoestesia de hemicuerpo izquierdo, así como paresia de miembro torácico izquierdo. Los estudios de extensión demuestran lesión axonal crónica de C1 a C3, de predominio izquierdo, los estudios de imagen evidencian inestabilidad axial y la resonancia magnética compresión bulbar. La paciente recibe tratamiento quirúrgico consistente en fijación posterior C1-C2, evolucionando satisfactoriamente.

Degenerative spondylolisthesis I: general principles.

Lumbar degenerative spondylolisthesis is the result of the progression from degenerative changes in the intervertebral disc and facet joints that lead to destabilizing one or more vertebral segments. It is characterized by the anterior sliding of the vertebral body secondary to the sagittalization of the facet joints. Wiltse, Newman, and Macnab classified it as type III. It is a pathology typical of elderly patients that predominate in women with a ratio of 5:1 compared to men; the most affected segment is L4-L5, the listhesis rarely exceeds 30% slip. It may or may not generate clinical manifestations, and the severity of these does not always correlate with the degree of sliding. The cardinal symptom is lumbar pain with or without radicular pain. Neurogenic claudication occurs in 75% of patients; it is caused by blood hypoperfusion secondary to the compression of the nerve roots, manifesting as pain in the lower limbs with variable walking distances. For the diagnosis of degenerative spondylolisthesis, comprehensive evaluation with static, dynamic radiographic studies in a standing position and magnetic resonance imaging are essential. The conservative treatment is the first-line therapy; it includes analgesics, anti-inflammatories, physiotherapy.

La espondilolistesis degenerativa lumbar es el resultado de la progresión de los cambios degenerativos en el disco intervertebral y las articulaciones facetarias que termina por inestabilizar uno o varios segmentos vertebrales. Se caracteriza por el deslizamiento anterior del cuerpo vertebral secundario a la sagitalización de las facetas articulares, Wiltse, Newman y Macnab la clasifican como tipo III. Es una patología propia de los pacientes de la tercera edad, predomina en mujeres con una relación de 5:1 respecto a los varones, el segmento más afectado es L4-L5, el desplazamiento rara vez supera el 30% de deslizamiento. Puede o no generar manifestaciones clínicas y la severidad de éstas, no siempre correlaciona con el grado de listesis. El síntoma cardinal es el dolor lumbar con o sin dolor radicular; mientras que la claudicación neurogénica se presenta en 75% de los pacientes, es causada por la hipoperfusión sanguínea secundaria a la compresión de las raíces nerviosas y se manifiesta como dolor en los miembros inferiores, con la deambulación a distancias variables. Para el diagnóstico de la espondilolistesis degenerativa es indispensable una evaluación integral con estudios radiográficos estáticos, dinámicos en posición de pie y resonancia magnética. La primera línea de tratamiento es el manejo conservador, este incluye analgésicos, antiinflamatorios, fisioterapia.

Lumbar degenerative spondylolisthesis II: treatment and controversies.

There are various approaches and surgical techniques with the objective of nerve root decompression, restrict mobility, and fusion of the listhesis. Among the techniques, posterior interbody fusion combines direct and indirect root decompression with the fusion between vertebral bodies, placing an autologous bone graft between transverse apophysis and vertebral bodies. Transforaminal lumbar and posterior interbody fusion, on the same way, look to decompress and fuse but with a different approach to the spine. The anterior approach for interbody fusion provides a better fusion rate. Lateral lumbar interbody fusion is considered less invasive, with an anterolateral transpsoas approach. The lumbar fusion technique in degenerative spondylolisthesis must be individualized. Non-fusion decompression is considered a less invasive procedure. Various studies suggest that decompression has better results when fusion is added. Surgery had several potential benefits and greater improvement in those patients who fail conservative management. An optimal technique is not conclusively identified.

El tratamiento de la espondilolistesis degenerativa lumbar es específico para cada etapa de la enfermedad y el manejo quirúrgico no debe de ser la primera elección en la mayoría de los casos. El manejo conservador está basado en el uso de antiinflamatorios no esteroideos, control de peso y rehabilitación. En caso de falla después de cuatro a seis semanas, el siguiente paso es la infiltración facetaria. En caso de dolor persistente, alteraciones neurológicas o claudicación neurogénica el siguiente paso es la cirugía. Existen varios abordajes y técnicas quirúrgicas con el objetivo de descomprimir las raíces nerviosas, restringir la movilidad y fusionar la listesis. Entre las técnicas quirúrgicas, la fusión posterior combina la descompresión directa e indirecta con artrodesis entre los cuerpos vertebrales, colocando injerto entre las apófisis transversas y los cuerpos vertebrales. La artrodesis intersomática transforaminal y posterior buscan de la misma manera la descompresión y fusión, pero con un abordaje distinto. El abordaje anterior para artrodesis intersomática provee la mejor tasa de fusión. La artrodesis intersomática lateral se considera un procedimiento menos invasivo, con un abordaje anterolateral transpsoas. La técnica de artrodesis lumbar en la espondilolistesis debe ser individualizada. La descompresión sin artrodesis se considera un procedimiento menos invasivo; varios estudios sugieren que la descompresión tiene mejores resultados cuando se agrega una artrodesis. La cirugía tiene múltiples beneficios posibles en pacientes en quienes el tratamiento conservador ha fallado. No se ha identificado una técnica óptima de tratamiento.

Ligamentum flavum in lumbar spinal stenosis, disc herniation and degenerative spondylolisthesis. An histopathological description.

INTRODUCCIÓN: Los cambios en el ligamento flavum (LF) relacionados con la degeneración son secundarios al proceso de envejecimiento o a la inestabilidad mecánica. Estudios anteriores han indicado que LF con envejecimiento muestra pérdida de fibras elásticas y aumento del contenido de colágeno, la pérdida de elasticidad puede hacer que el LF se pliegue en el canal espinal, disminuyendo su espacio. MATERIAL Y MÉTODOS: Se incluyeron 67 pacientes operados de estenosis lumbar espinal (LSS), hernia de disco lumbar (LDH) y espondilolistesis degenerativa (LDS). Se obtuvieron muestras de LF de pacientes que tenían LSS (39), LDH (22) y LDS (6). Se examinaron especímenes con respecto a metaplasia condroide, calcificación, fragmentación de fibras de colágeno, degeneración quística, apariencia fibrilar e hipercelularidad. RESULTADOS: Los cambios histopatológicos más frecuentes fueron la hialinización y la fragmentación de las fibras de colágeno (34%), neovascularización en 40.3%, y la disposición irregular de las fibras elásticas es el cambio más frecuente con 56.7% del total de muestras. Existe una diferencia en la presencia de cambios en el LF, de acuerdo con el diagnóstico, siendo estadísticamente significativo para la fragmentación de las fibras de colágeno (p = 0.045), la degeneración quística (p = 0.001), la apariencia fibrilar (p = 0.007) y la hipercelularidad (p = 0.005) todos ellos, siendo más frecuentes en el grupo LDS. El grupo LHD presentó fragmentación de las fibras de colágeno en 45.5% (p = 0.045) y la apariencia fibrilar en 4.5% (p = 0.009). CONCLUSIONES: No hay evidencia de hipertrofia celular en los análisis histopatológicos, el engrosamiento del LF se puede ver por abultamiento del mismo, seguido de colapso del segmento de movimiento.

INTRODUCTION: Changes in ligamentum flavum (LF) related to degeneration are secondary to either the aging process or mechanical instability. Previous studies have indicated that LF with aging shows elastic fiber loss and increased collagen content, loss of elasticity may cause LF to fold into the spinal canal, which may further narrow of the canal. MATERIAL AND METHODS: A total of 67 patients operated with the surgical indications of lumbar spinal stenosis (LSS), lumbar disc herniation (LDH) and lumbar degenerative spondylolisthesis (LDS) were included. LF samples were obtained from patients who had LSS (39), LDH (22) and LDS (6). Specimens were examined with regard to chondroid metaplasia, calcification, fragmentation of collagen fibers, cystic degeneration, fibrillar appearence, and hypercellularity. RESULTS: The most frequent histopathological changes were hyalinization and fragmentation of collagen fibers occur in 34%, neovascularization in 40.3% and irregular arrangement of elastic fibers is the most prevalent change with 56.7% of the total samples. There is a difference in the presence of certain changes in the LF according to the diagnosis, being statistically significant for fragmentation of collagen fibers (p = 0.045), cystic degeneration (p = 0.001), fibrillar appearance (p = 0.007) and hypercellularity (p = 0.005) all of these, being more prevalent in LDS group. LHD group presented fragmentation of collagen fibers in 45.5% (p = 0.045) and fibrillar appearance in 4.5% (p = 0.009). CONCLUSIONS: There is not evidence of cellular hyperthophy in the histhopatological analyses, thickening of the LF can be seen by bulking of LF followed by collapse of motion segment.

Demographic and clinical characteristics of patients with spinal cord injury: a single hospital-based study.

STUDY DESIGN: Retrospective study. OBJECTIVES: To evaluate the demographic and clinical characteristics of patients diagnosed with spinal cord injury (SCI) admitted to a single center. SETTING: Single center study, México. METHODS: This study reviewed 433 patients with SCI. Data were extracted from medical records and retrospectively reviewed. RESULTS: A total of 433 patients with a diagnosis of SCI were included in the analysis. Of these, 346 (79.9%) had traumatic SCI (TSCI) and 87 (20.1%) had non-traumatic SCI (NTSCI). The principal causes of traumatic TSCI were motor vehicle accidents in 150 patients (43.4%), falls in 107 patients (30.9%) and a result of firearms in 58 patients (16.8%). Tumoral cord compression was the main cause of NTSCI in 50 patients (57.4%), followed by degenerative disease-causing myelopathy in 17 patients (19.5%). The proportion of patients affected with NTSCI was significantly lower, 29.9 vs 79.1% (P=0.0001), the age of patients was higher 53.9 vs 37.8 (P<0.002) and SCI was less severe, AIS D 41.33 vs 9.5% (P=0.0001) compared with the TSCI group. CONCLUSIONS: The demographic profiles of patients with TSCI and NTSCI differ in terms of proportion of total SCIs, patient age, male:female ratio and incomplete vs complete injury. The most common etiology of TSCI was motor vehicle accidents (43.4%), and neurological lesions were complete in 62.7% of patients. The most common etiology of NTSCI was tumoral spinal lesions (57.4%), and lesions were incomplete in 75.8% of patients.

[Utility of ligamentoplasty for the prevention of adjacent segment disease above 360 degree arthrodesis in degenerative lumbar spondylosis. Preliminary report]. / Utilidad de la ligamentoplastía para la prevención de la artrodesis en espondilolistesis lumbar degenerativa. Reporte preliminar.

BACKGROUND: Ligamentoplasty is a dynamic stabilization method used to treat lumbar stenosis and resect lumbar herniated discs with good results. The objective of this paper is to report preliminary results of the utility of ligamentoplasty to prevent adjacent segment disease above the arthrodesis. MATERIAL AND METHODS: Two groups of patients with degenerative lumbar spondylolisthesis who underwent circumferential arthrodesis. In 23 patients a dynamic stabilization system was placed in the segment above (group L), while this system was not used in 35 patients (group S). Degeneration and disease of the segment above were assessed. The statistical analysis was done with the SPSS 15.0 software. RESULTS: At the one-year follow-up, the incidence rate of adjacent segment degeneration was 11% for group L and 0% for group S; at the two-year follow-up it was 13% in both groups; at three years, 0% for group L and 19% for group S; at four years, 25% for group L and 0% for group S. At five years, 50% for group L and 0% for group S. Clinically significant radiculopathy occurred in two patients five years after surgery, one of whom also had adjacent segment disease. CONCLUSIONS: Based on the follow-up, at this moment it is not possible to show the utility of dynamic stabilization through ligamentoplasty to avoid adjacent segment disease above the arthrodesis.

The impact of body mass index and central obesity on the spino-pelvic parameters: a correlation study.

INTRODUCTION: Obesity is an increasing problem of epidemic proportion, and it is associated with various musculoskeletal disorders, including impairment of the spine. However, the relationship between obesity and spino-pelvic parameters remains to date unsupported by an objective measurement of the mechanical behavior of the spino-pelvic parameters depending on body mass index (BMI) and the presence of central obesity. Such analysis may provide a deeper understanding of this relationship. PURPOSE: To assess whether BMI and central obesity are associated with modifications on spino-pelvic parameters and determine if exists any correlation between BMI and obesity with the type of lumbar lordosis (LL). METHODS: A cross-sectional study with 200 participants was conducted. Parameters measured were LL, pelvic tilt, sacral slope, and pelvic incidence (PI), using lumbosacral radiographs in lateral view. Subjects were classified depending on BMI. In a secondary analysis, the subjects were categorized into two groups depending on the presence or not of elevated abdominal circumference. The categorical variables were compared using Chi-square test, and the mean values were compared using ANOVA and student t test. A Spearman correlation test was used to analyze the correlation between BMI categories and LL types. RESULTS: From the total of participants, there were 51 (25.5 %) normal weight subjects, 93 (46.5 %) overweight, and 56 (28 %) obese individuals. The spino-pelvic parameters among these groups are practically equal. The correlation between the different BMI categories and LL types is poor 0.06 (P = 0.34). In a secondary analysis, grouping the participants in obese and non-obese, the results showed that obesity is modestly positively associated with increasing of spino-pelvic parameters values, in particular with PI (P = 0.078). The comparison made between the presence or not of central obesity, interestingly did not show significant differences. CONCLUSIONS: Despite the results did not reach statistically significant differences, the results indicate that the obese spine is slightly different from the non-obese spine. Therefore, this relationship deserves future attention.

[Comparison of three types of lumbar total disc arthroplasty. Four-year minimum follow-up]. / Comparación entre tres tipos de artroplastía total de disco lumbar. Seguimiento mínimo de 4 años.

BACKGROUND: Total lumbar disc replacement was developed to avoid the drawbacks of arthrodesis. This procedure should be done cautiously due to the various already known complications. The purpose of this study is to assess the clinical and radiographic results after single-level lumbar arthroplasty with the Prodisc-L, Maverick and Charité prostheses at our service. MATERIAL AND METHODS: A retrospective study was performed comparing the clinical and radiographic results of three groups of patients who underwent total lumbar disc arthroplasty from January 2000 to December 2007. RESULTS: Twenty-one lumbar prosthetic surgeries were performed. The Prodisc device was used in 13 patients, the Maverick in 4, and the Charité in 4. After the application of the Stauffer-Coventry scale, 16 patients reported excellent results and 5 good results. The mean preoperative interbody height was 7.9 mm and the mean postoperative height was 12.91 mm. The mean differential angle in the dynamic films was 5.47 degrees preoperatively and 4.61 postoperatively; the mean angle in neutral position was 13.38 preoperatively and 19.61 postoperatively. CONCLUSIONS: This study showed that the clinical result was good in all three groups. Mobility was better maintained with the Charité prosthesis compared to the Prodisc and Maverick devices. The three prostheses are appropriate for the treatment of lumbar degenerative disc disease.

Estimate of the frequency of Wilson's disease in the US Caucasian population: a mutation analysis approach.

The frequency of Wilson's disease in many populations is thought to be about one in 40000 persons, based on case and autopsy studies. Although the Wilson's disease gene has been identified, there is such a large number of mutations already known that it is not currently feasible to determine disease gene frequency by mutation analysis of a population. We have used a novel approach to obtain an estimate of the number of cases of Wilson's disease expected at birth in the US Caucasian population. We used data from four studies to determine that approximately one-third of Wilson's disease mutations in US Caucasian Wilson's disease patients are due to His-->Gln at the 1069 position. We then determined the frequency of this mutation in random DNA samples from 2601 US Caucasian newborns to be 0.285%. Multiplying by three gives an expected Wilson's disease heterozygote frequency of 0.855% and an allele frequency of 0.428%, or 0.00428. These data translate into a Wilson's disease frequency of about one in 55000 births. The 95% confidence interval is rather broad, ranging from about one in 18000 to one in 700000 births, but will be reduced as more data are added.