ABSTRACT
OBJETIVO: Definir una zona segura, usando como referencia la línea intercondílea anterior (LCA) del codo para realizar los bloqueos anteroposteriores durante el enclavijado endomedular retrógrado humeral (CEMR). MÉTODOS: Estudio experimental ex-vivo. Trece húmeros humanos fueron analizados. Se tomaron fotografías registrando la porción distal de los húmeros paralelos a la LCA, elevando el húmero distal 10cm. Tres evaluadores independientes realizaron las siguientes mediciones: ángulo del surco bicipital (SB) a la altura del cuello quirúrgico humeral (S, formado por las paredes medial y lateral del SB; zona de peligro) y el ángulo complementario lateral (formado por el límite lateral de la tróclea y la pared lateral del SB a la altura del cuello quirúrgico humeral; zona segura). RESULTADOS: Valor promedio de S: 3,1±0,5° (3,3-4), coeficiente de correlación intraclase: 0,057 (p=0,057). Valor promedio del ángulo complementario lateral: 87,5±3,3° (81,3-92,5), coeficiente de correlación intraclase: 0,304 (p=0,217). Considerando 3 desviaciones estándar del promedio de los ángulos medidos (para aumentar los parámetros de seguridad) la zona segura se enmarcó entre los 0° y los 80° con relación a la LCA. CONCLUSIÓN: En este estudio la zona de seguridad del bloqueo cefálico anteroposterior para evitar el daño del tendón bicipital durante el enclavijado endomedular retrógrado humeral se localizó entre los 0° y 80° con relación a la LCA.
OBJECTIVE: To define a safe zone, using the anterior intercondylar line (AIL) of the elbow as a reference to perform anterior-posterior (AP) cranial blocks during retrograde intramedullary humeral nailing (RIHN). METHODS: An ex-vivo experimental study was performed by analysing 13 human humeri. Photographs were taken, recording the distal portion of the humeri parallel to the AIL, elevating the distal humerus 10cm. Three independent evaluators made the following measurements: Bicipital groove (BG) angle at the level of the surgical neck of the humerus (S, formed by the medial and lateral walls of the BG; danger zone) and the Lateral Complementary Angle (LCA, formed by t5he lateral trochlear limit and the lateral wall of the BG at the level of the surgical neck of the humerus; safe zone). RESULTS: The mean value of S: 3.1±0.5° (3.3-4), intraclass correlation coefficient (ICC): 0.057 (P=.057). The mean value of the AIL: 87.5±3.3° (81.3-92.5), ICC: 0.304 (P=.217). Using 3 standard deviations from the mean of the angles measured (in order to increase the safety parameters), the safety zone is located between 0° and 80° in relation to the AIL. CONCLUSION: In this study, the safety zone of the AP cranial block, in order to avoid damage to bicipital tendon during RIHN, is situated between 0° and 80° in relation to the AIL.
Subject(s)
Humans , Bone Screws , Fracture Fixation, Intramedullary/methods , Humeral Fractures/surgery , Humerus/anatomy & histology , Bone Nails , CadaverABSTRACT
OBJETIVO: Determinar as áreas de risco em seis zonas do calcanhar e quantificar os riscos de lesão das estruturas anatômicas (artéria, veia, nervo e tendão). MÉTODO: Foram utilizados 53 calcâneos de cadáveres divididos em três zonas e subdivididas em duas áreas, superior e inferior, por meio de uma linha longitudinal do calcâneo. O risco de lesão das estruturas anatômicas em relação a cada fio de Kirschner foi determinado pelo sistema de graduação segundo a classificação de Licht. A quantificação do risco total de lesão das estruturas anatômicas na colocação de mais de um fio foi calculada pela lei aditiva das probabilidades e pela lei do produto para eventos independentes. RESULTADOS: O cálculo dos riscos de lesão, segundo a classificação de Licht, demonstrou que o risco de lesão da artéria ou veia na zona IA é mais expressivo (43%) em relação às lesões de nervo e tendão (13 e 0%, respectivamente). CONCLUSÃO: O estudo permitiu identificar as estruturas anatômicas mais vulneráveis e quantificar o risco de lesão no calcanhar.
OBJECTIVE: To determine the areas presenting risk in six zones of the calcaneus, and to quantify the risks of injury to the anatomical structures (artery, vein, nerve and tendon). METHOD: Fifty-three calcaneus from cadavers were used, divided into three zones and each subdivided in two areas (upper and lower) by means of a longitudinal line through the calcaneus. The risk of injury to the anatomical structures in relation to each Kirschner wire was determined using a graded system according to the Licht classification. The total risk of injury to the anatomical structures through placement of more than one wire was quantified using the additive law of probabilities and the product law for independent events. RESULTS: The injury risk calculation according to the Licht classification showed that the highest risk of injury to the artery or vein was in zone IA (43%), in relation to injuries to nerves and tendons (13% and 0%, respectively). CONCLUSION: This study made it possible to identify the most vulnerable anatomical structures and quantify the risk of injury to the calcaneus.
Subject(s)
Humans , Bone Nails , Calcaneus/injuries , Surgical Procedures, Operative/methods , CadaverABSTRACT
PURPOSE: To evaluate upper sacral morphology and anatomy of safe zone related to iliosacral screw fixation in Korean. MATERIALS AND METHODS: 100 patients performed pelvis 3D CT scan were evaluated. We used 16 channel CT and analyzed reconstructed image (shaded-surface display, transparent image and reformat image). RESULT: The angle between superior aspect of S1 body and iliac cortical density is 27.3°, between anterior cortical line of S1,2 body and horizontal plane 24.6°, and between superior aspect of S1 body and horizontal plane is 39.7°. The axis of S1, S2 pedicle is 32.5° and 15.6° toward anteromedial. The area of S1 pedicle according to sagittal plane and sagittal-oblique axis is 310.7 mm2 and 384.8 mm2. Also, S2 pedicle area is increased 163.1 mm2 to 188.4 mm2. The average depth of ala indentation is 5.1 mm and the maximal value is 9.5 mm. Distinct upper sacral dysplasia is 22%, transitional form is 32%. CONCLUSION: We measured Korean upper sacrum with 3D-CT, found out dysplasia come up to 54%. Considering the frequency of dysplasia, the investigation of anatomy and technique is essential to sacroiliac screw insertion.
Subject(s)
Humans , Pelvis , Sacrum , Tomography, X-Ray ComputedABSTRACT
BACKGROUND: The purpose of this study was to evaluate the anatomies of the internal jugular vein (IJV) and of the carotid artery (CA) using two-dimensional ultrasound in Koreans. METHODS: Thirty-five healthy people, who had never undergone IJV cannulation, underwent IJV and CA imaging. Vessels in the neck were imaged with a 7.5-MHz transducer, perpendicular to the spinal axis. The lateral diameter and cross-sectional area (CSA) of IJV, and overlap diameter, and neck circumference were measured. Thereafter, percent (%) overlap and safe zone were calculated. RESULTS: The mean right IJV size was measured as lateral diameter, 1.42 cm, and CSA, 1.0 cm2, and was greater than that of left IJV (lateral diameter, 16.5% +/- 23.2%; CSA, 22.4% +/- 36.3%). CSA of IJV increased according to body mass index (BMI), but did not for neck circumference and body weight. As neck circumference and body weight increased, percent overlap decreased and the IJV safe zone increased. However, percent overlap and safe zone were not significantly different for right and left vessels. In a majority of subjects, the IJV was located anterolaterally (42.9%) or laterally (51.4%) to the CA by ultrasound imaging. 11.4% of right IJVs and 15.4% of left IJVs observed unusually microvessels (< 0.5 cm2). CONCLUSIONS: In Koreans, right IJVs were larger than left IJVs, and BMI was best correlated with IJV size. Koreans have a normal anatomical relationship between IJV and CA, however microvessels are relatively frequent.
Subject(s)
Axis, Cervical Vertebra , Body Mass Index , Body Weight , Carotid Arteries , Catheterization , Jugular Veins , Microvessels , Neck , Transducers , UltrasonographyABSTRACT
PURPOSE: To evaluate the configuration of the anterior column of the acetabulum and to develop a safe path for screw placement for it. Materials and methods: Ten embalmed cadaveric adult bony-hemipelvis specimen were obtained. Each specimen was sectioned at 1cm intervals, beginning at the level of the inferior border of the acetabulum. The plane of the cross-section was perpendicular to the anterior column. The projection of the medial acetabular boundary on the anterior column was determined by analysis of each cross-section. RESULTS: The average width of the anterior column at 1.0, 2.0 and 3.0 cm superior to the inferior acetabular boundary was 27.9+/-4.3, 31.7+/-3.6 and 35.2+/-4.9 mm, respectively. At 1.0 cm superior to the inferior margin of the acetabulum, the average medial angulation for 0.5, 1.0 and 1.5 cm entry points lateral to the pelvic brim were 26.7+9.1 degree, 37.9+/-6.5 degreeand 46.1+/-5.0 degree, respectively. At 2.0 cm superior to the inferior acetabular margin, the corresponding average medial angulation for 0.5, 1.0 and 1.5 cm entry points were 20.4+/-6.2 degree, 30.4+/-5.6 degree and 41.0+/-5.0 degree, respectively. At 3.0 cm superior to the inferior acetabular margin, these angles were found to be 19.5+/-3.8 degree, 30.5+/-5.1 degree and 40.8+/-4.6 degree, respectively. CONCLUSIONS: This anatomical analysis of the acetabulum shows that it is possible to develop a safe path for screw placement into the anterior column. And the data could be a useful guide line for plate and screws fixation of the anterior column of the acetabulum.
Subject(s)
Adult , Humans , Acetabulum , CadaverABSTRACT
Among the various sacral fixation techniques used to enhance the strength of fixation, S1 screw placement in the sacrum is the most common method. Ventrolateral S1 screw placement through the sacral ala has been used alone or in combination with a medially-directed screw in the S1 pedicle to enhance pull-out resistance. Although the anatomical safe zone was identified, there is a risk of neurovascular injury particularly when the enhancement of fixation strength requires bicortical purchase. The purpose of this cadaver study is to re-evaluate the previous anatomical safe zone when using an S1 screw laterally directed toward the sacral ala. After dissecting the lateral safe zone of sacral ala in 12 human cadavers, K-wires were intentionally inserted deep into this zone. Each "safe" angle to the center of the safe zone was measured and the degree of risk to neurovascular structures was recorded on the basis of the distance in millimeters from the tips of the penetrating K-wires. The results are as follows: the mean safe angle to the center of the anatomical safe zone was 33.5degrees+/-9.3(20-50). Between 20 and 50 degrees, the range of safe angle was too wide. The distance between the tip of the K-wire and the sacroiliac joint, lumbosacral trunk, obturator nerve was 4.8mm+/-1(4-7.5), 6.8mm+/-1(6-9.5) and 6.8mm+/-3.2(0-10) respectively, while the anterior height between sacral cortex and lumbosacral trunk, internal iliac vein was 0mm and 2.1mm+/-1.8(0-5) respectively. In 29% of cases, the iliolumbar artery, the first branch of the internal iliac artery, abnormally crossed the middle of the safe zone. The sacroiliac joint, lumbosacral trunk, internal iliac vein and iliolumbar artery were at risk from laterally-directed S1 screws. This study shows that bicortical placement of S1 screws into the sacral ala presents unnecessary risks to neurovascular structures. It is concluded that the previous anatomical safe zone for bicortical S1 screw placement into the sacral ala was not surgically safe, and when lumbosacral fixation surgery is planned, operative techniques other than bicortical screw placement should be considered.
Subject(s)
Humans , Arteries , Cadaver , Iliac Artery , Iliac Vein , Intention , Obturator Nerve , Sacroiliac Joint , SacrumABSTRACT
The authors present the case of sciatica due to bicortical sacral screw impingement on the lumbosacral plexus across the anterior sacrum. The placement of sacral screw across the anterior sacral cortex carries significant inherent risks to neurovascular and visceral structures. However, the clinical reports of lumbosacral plexus involvement by the misplaced screw are not well documented in the literature. This is an unique case of sciatica due to sacral screw impingement on the lumbosacral plexus after motor vehicle accident(MVA), and confirmed by CT scan and intraoperative electrical stimulation. We reviewed sacral anatomy and preventive measures for avoiding complication of this type are discussed.