Félix Vílchez-Cavazos

Age- and gender-related variations in morphometric characteristics of thoracic spine pedicle: A study of 4,800 pedicles.

Transpedicular spinal fusion is the most commonly used fixation technique for the surgical treatment of vertebral disorders. However, the instrumentation of the thoracic spine using this technique continues to be controversial. The objective of the present study was to determine the morphometric characteristics of the thoracic pedicle and to establish how these characteristics vary with gender and age. Two hundred thoracic spines (4800 thoracic pedicles) from individuals of known gender and age were analyzed (in accordance with the order of vertebrae). The spines were divided into six groups according to age and gender. The horizontal and vertical diameters of the thoracic pedicle were determined for each piece. The mean and standard deviation of each variable were determined, and differences between age groups for each gender were evaluated using parametric correlation tests. The pedicle diameters of men and women differed significantly for most groups (P < 0.05). The horizontal diameters decreased from T1 to T5 and increased up to T12. The vertical diameter followed a cephalocaudal pattern of development from T1‐T12. The pedicle diameters decreased with increasing age in women, while the opposite trend was observed in men. In men, the dimensions of the thoracic spine pedicle increase with increasing age; in women, they decrease. These differences should be taken into account when selecting the appropriate pedicle screw. Clin. Anat. 27:441–450, 2014.

Plantar Fasciitis—A Comparison of Treatment with Intralesional Steroids versus Platelet-Rich Plasma

BACKGROUND Many treatment options for plantar fasciitis currently exist, some with great success in pain relief. The objective of our study was to compare the use of intralesional steroids with platelet-rich plasma (PRP), using pain scales and functional evaluation, in patients with plantar fasciitis who did not respond to conservative treatment. METHODS A controlled, randomized, blinded clinical assay was performed. Patients were assigned to one of the two groups by selecting a sealed envelope. The steroid treatment group received 8 mg of dexamethasone plus 2 mL of lidocaine as a local anesthetic. The PRP treatment group received 3 mL of PRP activated with 0.45 mL of 10% calcium gluconate. All of the patients were evaluated at the beginning of the study, and at 2, 4, 8, 12, and 16 weeks post-treatment with the Visual Analog Scale (VAS), Foot and Ankle Disability Index (FADI), and American Orthopedic Foot and Ankle Society (AOFAS) scale. RESULTS The right foot was the most frequently affected foot (63%). The average age of the patients was 44.8 years (range, 24-61 years). All scales used (VAS, FADI and AOFAS) showed that the difference was not statistically significant between the two groups. CONCLUSIONS We can conclude that the use of PRP is an effective treatment method for patients with plantar fasciitis who do not respond to conservative treatment because PRP demonstrates an efficacy equal to that of steroids. However, the cost and the time for preparation the PRP are two of the disadvantages of this treatment.

The effect of intra-articular injection of autologous bone marrow stem cells on pain and knee function in patients with osteoarthritis

Management of osteoarthritis (OA) is basically symptomatic. Recently, stem cells (SC) have been used in the search for an optimum treatment. We decided to conduct a controlled clinical trial to determine if a single intra‐articular injection of in vivo stimulated bone marrow SC could lead to an improvement in pain management and quality of life in patients with knee OA.

A new Morphological Classification of the Anterior Inferior Iliac Spine: Relevance in Subspine Hip Impingement

El Sindrome de Pinzamiento Femoroacetabular (PFA) es una entidad clinica reconocida en los ultimos anos como una causa de dolor y desarrollo de artrosis temprana de cadera. El pinzamiento subespinoso de la cadera se caracteriza por una espina iliaca anteroinferior (EIAI) prominente o con una morfologia anormal, lo que contribuye al desarrollo de un cuadro clinico similar al PFA. El objetivo fue proponer una nueva clasificacion morfologica de la EIAI y determinar las prevalencias de las distintas morfologias de la EIAI en base a la misma y correlacionarla con los distintos sexos y grupos de edad. La muestra consistio en un total de 458 hemipelvis, de sexo y edad conocidos (264 hombres y 194 mujeres). Cada pieza fue analizada para determinar la prevalencia de variaciones morfologicas de la EIAI en base a la clasificacion propuesta. Tipo 1: presencia de una superficie concava entre la EIAI y reborde acetabular, Tipo 2A: presencia de una superficie plana entre la EIAI y el reborde acetabular, Tipo 2B: presencia de una superficie convexa entre la EIAI y el reborde acetabular y Tipo 3: la EIAI protruye hacia el acetabulo anterior o inferiormente. Se determino una prevalencia de 69,87% para la EIAI Tipo 1 (320/458). En cuanto a las morfologias anormales, se determino una prevalencia de 17,90% (82/458), 3,71% (17/458) y 8,52% (39/459) para los Tipos 2A, 2B y 3, respectivamente. La prevalencia de una morfologia anormal en las EIAI de especimenes del sexo masculino fue de 30,30% (80/264) y en el sexo femenino 29,90% (58/194). Se evidencia la prevalencia de las diferentes morfologias que puede tener la EIAI; esta informacion sera de ayuda para determinar el papel de la EIAI en la aparicion del pinzamiento subespinoso de la cadera.

Safe Areas for the Placement of Standard Shoulder Arthroscopy Portals: An Anatomical Study

The abundant vascular structures that surround the shoulder joint are complex and variable, complicating arthroscopy approaches. The aim of this study is to determine safe and risky areas around standard posterior and standard anterior portals, and accounting for the distribution of neurovascular structures of small and medium diameters that can lead to intra-articular bleeding during surgery. The standard posterior portal, and standard anterior portal were placed as described in the literature, and punch dissection was performed 2.5 cm around the trocar in situ. The arrangement of each identified structure was photographically documented and digitalized for each anatomic plane; the distance to the trocar and the diameter of each structure were measured. Based on each digitalized anatomic plane, safe and risky tissue areas were determined, and a clock face coordinate system was used to represent these areas. The safe area around the standard posterior portal was located between 11 and 1 o´clock for the left shoulder and 11 and 2 o´clock for the right shoulder. For the standard anterior portal, the safe area was located between 2 and 3 o´clock for the left shoulder and between 9 and 12 o´clock for the right shoulder. However, we did document a risk of injuring the cephalic vein 5 times, the axillary artery 3 times and the deltoid branch of the thoracoacromial artery once. This study reports quantitatively the total number of small diameter structures present in the two shoulder arthroscopic portals evaluated. The safe areas proposed in this study must be evaluated to propose new access points for performing arthroscopic procedures on the shoulder.

Neurovascular structures at risk during anterolateral and medial arthroscopic approaches of the hip

El objetivo fue describir las areas de seguridad para la colocacion de 5 portales estandar (portal anterior, anterolateral, posterolateral, portal anterior proximal medial y portal anterior distal medial) y 3 portales mediales emergentes (antero medial, portal posteromedial y posteromedial distal) para proporcionar una descripcion topografica de la seguridad de cada portal. Se realizo un estudio descriptivo, observacional y transversal, en la que se diseco el triangulo femoral de 12 caderas. Se colocaron los 5 portales laterales y los 3 portales mediales. Se documento la medicion de cada estructura neurovascular de relevancia clinica en relacion a cada uno de los portales evaluados. En cuanto al portal de mayor riesgo entre los laterales, se encontro el portal anterior con mayor cercania al nervio cutaneo femoral lateral (1,42±0,85 cm), ubicado lateral al portal. En los portales mediales el portal anterior medial tiene el margen mas estrecho respecto a la arteria femoral (2,14±0,35 cm) lateral al portal, y medial el nervio obturador (0,87±0,62 cm). Los portales laterales tienen un amplio margen de seguridad, el portal con el margen mas reducido es el portal anterior en relacion al nervio cutaneo femoral lateral, presentando un elevado riesgo de lesionarlo, los portales mediales tienen un alto riesgo de lesionar las estructuras neurovasculares femorales y el nervio obturador.

Anthropometric Landmarks for Posterior Cruciate Ligament Reconstruction in Anatomical Position

El proposito del estudio fue determinar referencias anatomicas viables para la correcta colocacion de los tuneles femorales y tibiales en posicion anatomica durante la reconstruccion del ligamento cruzado posterior (LCP). Se utilizaron 10 rodillas, las cuales fueron disecadas para analizar las mediciones de la insercion femoral y tibial del LCP, sus fasciculos y estructuras adyacentes. Se utilizo el sistema de las manecillas del reloj para la medicion de las inserciones femorales. Los meniscos y el ligamento cruzado anterior (LCA) fueron utilizados como referencias para la medicion de las inserciones tibiales. El LCP y las caracteristicas de sus fasciculos correspondientes fueron determinados por su insercion femoral, porcion central e insercion tibial. La media de la longitud entre la porcion central de la huella dejada por el LCP y el margen anterior del cartilago femoral a las 12:00 h fue de (±3.94) y 17,73 mm (±4,11) para la rodilla derecha e izquierda, respectivamente. La longitudes del LCP fueron de 11,94 mm (±5,08) entre el margen posterior del LCP y el margen anterior del LCP. La media fue de 33,52 mm (±3,49) desde el margen medial del menisco lateral al margen lateral del LCP y de 32,24 mm (±2,28) del margen medial del menisco medial al margen medial del LCP. Desde el punto de vision anteroposterior, el fasciculo anterolateral es mayor que el posteromedial tanto en su insercion femoral como en el punto central e insercion tibial. Se analizo una coleccion cuantitativa de bases de datos con distintas variables del LCP, asi como de sus fasciculos y sus inserciones femorales y tibiales. Se obtuvieron varias medidas, indicando la alta funcionalidad compartida por los fasciculos del LCP. Las inserciones reportadas son referencias practicas para la localizacion de los tuneles tibiales y femorales durante la plastia del ligamento cruzado posterior.

Results of External Fixation and Metatarsophalangeal Joint Fixation With K-Wire in Brachymetatarsia:

Background: Brachymetatarsia is a rare foot deformity caused by the premature closure of the metatarsal physis. It may result in functional as well as cosmetic alterations, which may require operative management. Methods: A prospective study examining outcomes of 48 cases of brachymetatarsia with gradual bone lengthening at a rate of 1 mm/d using an external fixator and metatarsophalangeal joint fixation was performed. The difference between the length before treatment and after external fixator removal was measured. The patients were assessed at 2, 4, 6, and 8 weeks postoperatively; at the end of the period of distraction; and 1 year after surgery. The total number of patients was 26, and surgery was performed in 48 metatarsals. The mean age was 17.0 ± 4.1 (range, 11-24) years, and all were female. Results: The fourth metatarsal was the most frequently affected, representing 98% of the cases; the third metatarsal represented the other 2%. The average length gained was 18.6 ± 6.7 mm, and the average length gained as a proportion of the original metatarsal length was 38.2% ± 3.1% (range, 13%-24%). The mean healing time was 71.0 (range, 64-104) days, and the mean healing index (healing time divided by centimeters of length gained [d/cm]) was 38.4 (range, 38.2-50.1) d/cm. Conclusion: Gradual bone lengthening at a rate of 1 mm/d using an external fixator and intramedullary nailing was a safe and efficient method, representing a minimally invasive procedure with a low incidence of complications and satisfactory results for the patient. Level of Evidence: Level IV, retrospective case series.

Comments on: Implications of structural variations in the human sacrum: why is an anatomical classification crucial?

We sincerely appreciate the work done by Mahato [1] in which a qualitative classification of the sacrum is done to determine the number of segments, position of auricular surfaces, symmetry and abnormalities. This work is of the utmost importance since it is crucial for several surgical interventions and at the same time correlates certain pathologies with the morphology, mostly low back pain. It would be of great benefit having a quantitative study of the sacrum, like the one performed by our working group, Morales et al. [2], in which the morphometric characteristics (sacral foramina, pedicles, vertebral body and sacral canal) of 50 sacral specimens in Mexican population were obtained. With this information it is possible to determine the most prevalent characteristics that are present in the sacrum in Mexican population, which are critical for a safe intervention and compare them with the existing literature. In our work it was possible to establish that the pedicle length of S1 was longer than reported in previous studies. We recommend performing a similar study to the working group of Mahato, in which the morphometric characteristics of the sacral in Indian population are obtained, with this adding valuable information to the proposed classification in predicting the most prevalent measures. This would give a chance to have safer procedures after having done a clinical correlation of the pathology based on Mahato [1] and predict the sacrum measurements based on a similar study to ours, with this having correct screw placement and position in lumbosacral instrumentation, and also for other procedures that involves the sacral region as surgical and diagnostic target. The classification proposed by the working group of Mahato is of essential importance since it correlates the form and characteristics of the sacrum with the patient symptoms and gives valuable information to the surgeon that will perform a procedure. Besides, it presents information on the several variations present on the sacrum to be able to identify them. We consider it is important to take into account both analyses [1, 2].

Clinical, biomechanical and morphological assessment of anterior cruciate ligament Kevlar®-based artificial prosthesis in rabbit model

Background The aim of this study was to evaluate the clinical, biomechanical and morphological characteristics of a Kevlar®-based prosthetic ligament as a synthetic graft of the anterior cruciate ligament (ACL) in an experimental animal model in rabbits. Methods A total of 27 knees of rabbits randomly divided into 3 groups (control, ACL excision and ACL replacement with a Kevlar® prosthesis) were analyzed using clinical, biomechanical and morphological tests at 6, 12 and 18 weeks postprocedure. Results The mean displacement in mechanical testing was 0.73 ± 0.06 mm, 1.58 ± 0.19 mm and 0.94 ± 0.20 mm for the control, ACL excision and ACL replacement with synthetic prosthesis groups, respectively. The results showed an improvement in the stability of the knee with the use of the Kevlar® synthetic prosthesis in the biomechanical testing (p<0.05) compared with rabbits that underwent ACL excision, in addition to displacements that were larger but comparable to that in the control group (p>0.05), between the replacement group and the control group. The histological study revealed a good morphological adaptation of the synthetic material to the knee. Conclusions This study proposes a new animal model for the placement and evaluation of Kevlar®-based synthetic ACL implants. The studied prosthesis showed promising behavior in the clinical and biomechanical tests and in the histological analysis. This study lays the foundation for further basic and clinical studies of artificial ACL prostheses using this material.