Anatomical study of the infrapatellar branch of the saphenous nerve with applications to knee surgery / Estudio anatómico de la rama infrapatelar del nervio safeno con aplicaciones a la cirugía de rodilla

The infrapatellar branch of the saphenous nerve is a cutaneous nerve that innervates the area surrounding the patella and contributes to the peripatellar plexus. This nerve is target to iatrogenic injuries during a great deal of knee procedures, such as tendon harvesting, total knee arthroplasty and medial arthroscopic approaches to the knee. Lesion to this nerve can produce sensorial loss at its innervation territory. The study conducted herein aims to observe the anatomical aspects of the infrapatellar branch in cadaveric specimens. The infrapatellar branch of the saphenous nerve of 40 male cadavers was dissected with the purpose of identifying the number of branches, its relation with the patella, tibial tuberosity and sartorius muscle. The nerve was dissected and several measurements were performed with the aid of a digital caliper. Statistical analysis was performed with the MedCalc 16.1 software. The infrapatellar branch of the saphenous nerve was present in 100 % of the sample. Its mean distance from its origin to its branching point was 16.35±6.48 mm on the right and 21.94±4.31 mm on the left, with statistically significant differences (p < 0.05). A relatively safe zone for surgery was observed on the superior and medial aspect of the patella, which received less branches.

La rama infrapatelar del nervio safeno es un nervio cutáneo que inerva el área que rodea la patela y contribuye al plexo peripatelar. Este nervio es objeto de lesiones iatrogénicas durante una gran cantidad de procedimientos de rodilla, como la extracción de tendones, la artroplastía total de rodilla y los abordajes artroscópicos mediales de la rodilla. La lesión de este nervio puede producir pérdida sensorial en su territorio de inervación. El estudio realizado aquí tiene como objetivo observar los aspectos anatómicos de la rama infrapatelar en muestras de cadáveres. La rama infrapatelar del nervio safeno de 40 cadáveres masculinos se disecó con el propósito de identificar el número de ramas, su relación con la patela, la tuberosidad tibial y el músculo sartorio. Se disecó el nervio y se realizaron varias mediciones con la ayuda de un calibrador digital. El análisis estadístico se realizó con el software MedCalc 16.1. La rama infrapatelar del nervio safeno estaba presente en el 100 % de las muestras. La distancia media desde su origen hasta su punto de ramificación fue de 16,35±6,48 mm a la derecha y de 21,94±4,31 mm a la izquierda, con diferencias estadísticamente significativas (p <0,05). Se identificó una zona relativamente segura para la cirugía en el aspecto superior y medial de la patela, que recibió menos ramas.

Correlation between tooth size-arch length discrepancy and interradicular distances measured on CBCT and panoramic radiograph: an evaluation for miniscrew insertion

Abstract Introduction: The selection of appropriate sites for miniscrew insertion is critical for clinical success. Objectives: The aim of the present study was to evaluate how interradicular spaces measured on panoramic radiograph compare with Cone-Beam Computed Tomography (CBCT), and how crowding can influence the presence of available space for miniscrew insertion, in order to define a new "safe zones" map. Methods: A total of 80 pre-treatment panoramic radiographs and 80 CBCT scans with corresponding digital models were selected from the archives of the department of Dentistry, Aarhus University. Crowding was measured on digital models, while interradicular spaces mesial to the second molars were measured on panoramic radiographs and CBCTs. For panoramic radiographs, a magnification factor was calculated using tooth widths measured on digital models. Statistical analyses were performed to investigate the correlation between the amount of crowding and the available interradicular space. Visual maps showing the amount of interradicular spaces measured were drawn. Results: The most convenient interradicular spaces are those between the second molar and the first premolar in the mandible, and between the central incisors in the maxilla. However, some spaces were revealed to be influenced by crowding. Conclusions: Calibration of panoramic radiographs is of utmost importance. Generally, panoramic radiographs underestimate the available space. Preliminary assessment of miniscrew insertion feasibility and the related selection of required radiographs can be facilitated using the new "safe zone" maps presented in this article.

Resumo Introdução: a seleção de locais apropriados para a inserção de mini-implantes é crítica para o sucesso clínico. Objetivo: os objetivos do presente estudo foram avaliar as medições de espaços inter-radiculares feitas em radiografias panorâmicas e compará-las com as medições feitas com tomografia computadorizada de feixe cônico (TCFC), além de avaliar como o apinhamento pode influenciar na disponibilidade de espaços para inserção dos mini-implantes, no intuito de definir um novo mapa de "áreas seguras". Métodos: foram selecionadas, nos arquivos do departamento de Ortodontia da Aarhus University, 80 radiografias panorâmicas pré-tratamento e 80 imagens de TCFC com os modelos digitais correspondentes. O apinhamento foi medido nos modelos digitais, enquanto os espaços inter-radiculares mesiais aos segundos molares foram medidos nas radiografias panorâmicas e na TCFC. O fator de magnificação das radiografias panorâmicas foi calculado utilizando-se as larguras dentárias medidas nos modelos digitais. Análises estatísticas foram realizadas para investigar a correlação entre a quantidade de apinhamento e o espaço inter-radicular disponível. Foram desenhados mapas visuais mostrando a quantidade dos espaços inter-radiculares medidos. Resultados: os espaços inter-radiculares mais adequados são aqueles entre o segundo molar e o primeiro pré-molar inferior, e entre os incisivos centrais superiores. Porém, verificou-se que alguns espaços são influenciados pelo apinhamento. Conclusões: A calibração das radiografias panorâmicas é de suma importância, pois, geralmente, as radiografias panorâmicas subestimam o espaço disponível. A avaliação preliminar da viabilidade de inserção dos mini-implantes e a seleção das radiografias necessárias para isso podem ser facilitadas utilizando-se os novos mapas de "áreas seguras" aqui apresentados.

Average interradicular sites for miniscrew insertion: should dental crowding be considered?

ABSTRACT Objective: To define a map of interradicular spaces where miniscrew can be likely placed at a level covered by attached gingiva, and to assess if a correlation between crowding and availability of space exists. Methods: Panoramic radiographs and digital models of 40 patients were selected according to the inclusion criteria. Interradicular spaces were measured on panoramic radiographs, while tooth size-arch length discrepancy was assessed on digital models. Statistical analysis was performed to evaluate if interradicular spaces are influenced by the presence of crowding. Results: In the mandible, the most convenient sites for miniscrew insertion were in the spaces comprised between second molars and first premolars; in the maxilla, between first molars and second premolars as well as between canines and lateral incisors and between the two central incisors. The interradicular spaces between the maxillary canines and lateral incisors, and between mandibular first and second premolars revealed to be influenced by the presence of dental crowding. Conclusions: The average interradicular sites map hereby proposed can be used as a general guide for miniscrew insertion at the very beginning of orthodontic treatment planning. Then, the clinician should consider the amount of crowding: if this is large, the actual interradicular space in some areas might be significantly different from what reported on average. Individualized radiographs for every patient are still recommended.

RESUMO Objetivo: elaborar um mapa dos espaços inter-radiculares nos quais os mini-implantes podem ser inseridos, em um nível coberto por gengiva inserida; e avaliar se existe correlação entre o apinhamento dentário e a disponibilidade de espaços. Métodos: radiografias panorâmicas e modelos digitais de 40 pacientes foram selecionados seguindo critérios de inclusão. Os espaços inter-radiculares foram medidos nas radiografias panorâmicas, enquanto a discrepância de modelo foi avaliada nos modelos digitais. Realizou-se, então, uma análise estatística para avaliar se os espaços inter-radiculares foram influenciados pela presença do apinhamento dentário. Resultados: na mandíbula, os locais mais adequados para a inserção dos mini-implantes foram os espaços compreendidos entre os segundos molares e primeiros pré-molares; na maxila, entre os primeiros molares e segundos pré-molares, bem como entre caninos e incisivos laterais, e entre os dois incisivos centrais. Os espaços inter-radiculares entre os caninos e incisivos laterais superiores e entre o primeiro e o segundo pré-molares inferiores mostraram-se influenciados pela presença do apinhamento dentário. Conclusões: o mapa dos espaços inter-radiculares mais adequados aqui proposto pode ser adotado como um guia geral para a inserção de mini-implantes, e pode ser usado logo ao início do planejamento do tratamento ortodôntico. Em seguida, o clínico deve levar em consideração a quantidade de apinhamento: caso esse seja grande, o real espaço inter-radicular, em algumas áreas, poderá ser significativamente diferente da média aqui relatada. Assim, recomenda-se que sempre sejam feitas radiografias individualizadas para cada paciente.

The relationship of the posterior interosseous nerve to the supinator muscle in the dorsal approach to the proximal radius: A descriptive and quantitative anatomic study of Filipino cadavers

BACKGROUND AND OBJECTIVE:The posterior interosseous nerve (PIN) is vulnerable to injury in the dorsal approach to the proximal radius. The goal of this study is to describe the quantitative relationship of the PIN to the supinator muscle in the context of anatomic landmarks. Knowledge of superficial landmarks related to the PIN would hopefully minimize iatrogenic injury to the posterior interosseous nerve.METHODS: 12 cadavers (22 forearms) were dissected and analyzed. The length of the supinator muscle was determined. The oblique distances of the PIN entry and exit points to the proximal and distal borders of the supinator muscle as well as their perpendicular distances to the lateral epicondyle-Lister's tubercle (LE-LT) reference line were measured and recorded. The number of PIN branches inside the supinator substance was recorded. Mean and median values were determined and subjected to statistical analysis.RESULTS: Mean supinator length was 5 centimeters. Ninety-one percent of the cadaveric forearms had PIN branches inside the supinator muscle substance. Twelve of the 22 forearms (55%) had 2 branches. The mean oblique distances of the PIN from the lateral epicondyle to the entry and exit points in the proximal and distal borders of the supinator muscle was 3.52 and 7.31 centimeters, respectively. The mean perpendicular distances of the PIN from LE-LT reference line to the entry and exit points in the proximal and distal borders of the supinator muscle was 1.13 and 1.26 centimeters, respectively. An imaginary danger-zone 4 centimeters wide overlying the LE-LT reference line depicts the possible area where the PIN and its branches may most likely be located.CONCLUSION: The dorsal approach to the proximal radius may allow a safe exposure without causing iatrogenic injury to the posterior interosseous nerve through the use of superficial anatomic landmarks and reference lines in combination with mean measurements from our study.

The safe zones of posterior miniscrew implant placement in different sagittal skeletal features / 实用口腔医学杂志

Objective:To measure the mesio-distal interradicular space of posterior teeth at different height by CBCT.Methods:60 subjects with skeletal Class Ⅰ,Ⅱ and Ⅲ patterns were included(n =20).From the distal of first premolar to the mesial of second molar,the mesiodistal width at the height of 2,4,6,8 and 10 mm from the alveolar crest were measured and analysed.Results:The interradicular distance was larger than 3 mm within 4-10 mm height in maxilla and in mandible.The maxillary mesiodistal width values measured between the first premolar and second premolar in skeletal Class Ⅰ and Class Ⅱ pattern was greater than that in Class Ⅲ(P ＜0.05) and there was no significant difference in other zones.In the mandible,the values of skeletal Class Ⅲ pattern were greater than those of skeletal Class Ⅰ and Class Ⅱ pattern(P ＜0.05).Conclusion:The suitable interradicular zone is within 4-8 mm to the alveolar crest between the second premolar and first molar for miniscrew implant placement in maxilla,and over 4 mm between the first molar and second molar in mandible.The difference of interradicular spaces in sagittal skeletal features is existed.

The relationship of the posterior interosseous nerve to the supinator muscle in the dorsal approach to the proximal radius: A descriptive and quantitative anatomic study of Filipino cadavers

@#<p style="text-align: justify;"><strong>BACKGROUND AND OBJECTIVE:</strong>The posterior interosseous nerve (PIN) is vulnerable to injury in the dorsal approach to the proximal radius. The goal of this study is to describe the quantitative relationship of the PIN to the supinator muscle in the context of anatomic landmarks. Knowledge of superficial landmarks related to the PIN would hopefully minimize iatrogenic injury to the posterior interosseous nerve.<br /><strong>METHODS:</strong> 12 cadavers (22 forearms) were dissected and analyzed. The length of the supinator muscle was determined. The oblique distances of the PIN entry and exit points to the proximal and distal borders of the supinator muscle as well as their perpendicular distances to the lateral epicondyle-Lister's tubercle (LE-LT) reference line were measured and recorded. The number of PIN branches inside the supinator substance was recorded. Mean and median values were determined and subjected to statistical analysis.<br /><strong>RESULTS:</strong> Mean supinator length was 5 centimeters. Ninety-one percent of the cadaveric forearms had PIN branches inside the supinator muscle substance. Twelve of the 22 forearms (55%) had 2 branches. The mean oblique distances of the PIN from the lateral epicondyle to the entry and exit points in the proximal and distal borders of the supinator muscle was 3.52 and 7.31 centimeters, respectively. The mean perpendicular distances of the PIN from LE-LT reference line to the entry and exit points in the proximal and distal borders of the supinator muscle was 1.13 and 1.26 centimeters, respectively. An imaginary danger-zone 4 centimeters wide overlying the LE-LT reference line depicts the possible area where the PIN and its branches may most likely be located.<br /><strong>CONCLUSION:</strong> The dorsal approach to the proximal radius may allow a safe exposure without causing iatrogenic injury to the posterior interosseous nerve through the use of superficial anatomic landmarks and reference lines in combination with mean measurements from our study.</p>