RESUMEN
Three purposes of this study were to: 1) describe the sustentaculum tali in relation to surrounding structures, 2) identify its radiographic projection onto the lateral calca neus, and 3) determine optimal angles for screw placement. Twelve cadaver specimens were used. The length a width of the sustentaculum was measured. Its midpoint was measured from surrounding anatomic landmarks. A point on the lateral calcaneal wall "point A" was chosen. This marks the intersection of two lines bisecting the midpoint of the posterior facet and the lateral calcaneal height. The angles required to pass a pin from point A into the sustentaculum were determined. The sustentaculum projected as a triangular/elliptical structure on the lateral radiograph. It was superimposed on the anterior portion of the posterior facet.
Asunto(s)
Calcáneo/anatomía & histología , Fijación Interna de Fracturas/instrumentación , Articulación Talocalcánea/anatomía & histología , Articulación Talocalcánea/cirugía , Astrágalo/anatomía & histología , Adulto , Tornillos Óseos , Cadáver , Calcáneo/diagnóstico por imagen , Calcáneo/cirugía , Femenino , Fijación Interna de Fracturas/métodos , Humanos , Masculino , Radiografía , Sensibilidad y Especificidad , Articulación Talocalcánea/diagnóstico por imagen , Astrágalo/diagnóstico por imagen , Astrágalo/cirugíaRESUMEN
The glenoid articular surface is best studied radiographically on a tangential projection with both true anteroposterior and axillary views. Forty-one dry scapulas were studied under fluoroscopy to define the axillary projection that would provide a true scapular lateral view. The superior and inferior articular margins were marked with radiopaque solder wires. A true axillary view was obtained when the projection of the wires superimposed. The projection of the cortical bone of the posterolateral surface of the coracoid was noted to be continuous with the projection of the subchondral cortical bone of the glenoid articular surface when the latter was viewed tangentially. An illustrative case is shown in which a screw was mistakenly seen violating the glenohumeral joint; however, with the defined true axillary view, the actual position of the screw was demonstrated. X-ray films taken of another 8 cadaver shoulders were used to study the position of screws inserted about the glenoid articular surface. The soft tissue shadow superimposition on the inferior glenoid margin can lead to a misinterpretation of the superior margin as the whole glenoid articular surface. Because soft tissue can interfere with the appreciation of the glenohumeral joint line on an axillary view, a projection that will show a continuous line of the coracoid and glenoid articular surface should be obtained, and it will indicate a tangential view of the joint.
Asunto(s)
Escápula/diagnóstico por imagen , Articulación del Hombro/anatomía & histología , Articulación del Hombro/diagnóstico por imagen , Adulto , Artroscopía/métodos , Axila , Clavos Ortopédicos , Cadáver , Fluoroscopía , Fijación Interna de Fracturas/instrumentación , Humanos , Cápsula Articular , Escápula/anatomía & histología , Sensibilidad y Especificidad , Fracturas del Hombro/diagnóstico por imagen , Fracturas del Hombro/cirugía , Propiedades de SuperficieRESUMEN
Thirty adult bony scapulae were used to report detailed bony dimensions of the scapula. The measurements of bony dimensions of the scapula included the glenoid, coracoid, spine, and body. The results of the measurements showed that the thickest bony stock (posteroanterior diameter), with a mean value of 13 mm to 23 mm in the glenoid process, was found in the middle third of the area within 1 cm medial to the glenoid rim. In the scapular spine region, the greatest superoinferior diameter of the bone was noted in the lateral portion of the spine, followed by the medial portion. It was also found that smallest superoinferior diameter (2 mm to 7 mm) of the spine was located at the middle portion between the base and ridge along the whole spine. On the lateral border of the scapula, the posteroanterior diameter of bone was relatively greater for the upper portion (8 mm) than for the lower portion, including the inferior angle (6 mm). This information may be helpful in open reduction and internal fixation of significantly displaced scapular fractures.
Asunto(s)
Escápula/anatomía & histología , Adulto , Antropometría , HumanosRESUMEN
Seven adult cadaver lumbopelvises were harvested to study the anatomic relationship of the L4 and L5 nerves to S1 dorsal screw placement and the location of the L4, L5, and S1 nerves on plain radiographs. The mean lateral angle of S1 screw trajectory toward the L4 nerve was 31+/-8 degrees, and the mean screw trajectory length was 53+/-8 mm. The mean lateral angle of the screw trajectory toward the L5 nerve was 21+/-8 degrees, and the mean screw trajectory length was 38+/-4 mm. On both inlet and outlet radiographs, the lateral angle of the nerves increased from L4 to S1. The L4 nerve coursed over the middle third of the superior ala in the inlet view and the middle third of the lateral mass in the outlet view. The L5 nerve coursed over the inner third of the superior ala and inner third of the lateral mass. On the lateral view, the mean distances from the sacral promontory to the L4, L5, and S1 nerves along the anterior border of the sacrum were 4+/-7 mm, 12+/-5 mm, and 28+/-8 mm, respectively. This study suggests that S1 sacral screws be directed between 30 degrees and 40 degrees lateral to avoid compromising the lumbosacral trunk and sacroiliac joint.
Asunto(s)
Tornillos Óseos , Plexo Lumbosacro/anatomía & histología , Región Lumbosacra/diagnóstico por imagen , Sacro/cirugía , Adulto , Fenómenos Biomecánicos , Cadáver , Femenino , Humanos , Región Lumbosacra/anatomía & histología , Masculino , Huesos Pélvicos/anatomía & histología , Huesos Pélvicos/diagnóstico por imagen , Radiografía , Sacro/anatomía & histologíaRESUMEN
Twenty cadaver fifth metatarsals were harvested from cadaver feet. They were then sectioned coronally in three locations. The cortical thickness (medial, lateral, dorsal, and plantar) and the intra-medullary canal diameter (dorsoplantar and mediolateral) were measured at the three sectional sites. The intra-medullary canal of six specimens was outlined with radiopaque solder wire. The canal was then examined radiographically with the lateral and dorsoplantar views. A lateral bow on the dorsoplantar view was observed in some specimens, which could contribute to surgical complications. On lateral view the intramedullary canal appeared straight in all specimens. The canal projects at least partially into the fifth metatarsal cuboid joint. When considering intra-medullary fixation a surgeon must take into account quality of bone stock and bowing of the canal. A bowed intra-medullary canal lends to vulnerability of the medial cortex at roughly mid-shaft of the fifth metatarsal. The canal has a narrower diameter in the dorsoplantar dimension than the mediolateral dimension. The cortical thickness was found to be less in the dorsal and plantar areas of the fifth metatarsal when compared to medial and lateral cortex. All of these findings lead to causes for complication in intra-medullary fixation of the fifth metatarsal.
Asunto(s)
Huesos Metatarsianos/anatomía & histología , Huesos Metatarsianos/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Cadáver , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Valores de Referencia , Sensibilidad y EspecificidadRESUMEN
A new derotation device for corrective femoral osteotomy is reported. This device helps eliminate errors of undercorrection and overcorrection in derotational osteotomies of femurs with torsional deformities. A prototype of the intraoperative rotational measuring device was tested on 16 cadaver femurs. This experiment conclusively demonstrated that this simple device is easy to use and a mathematical precision (P < 0.05) is accomplished in rotational corrections by surgical means.
Asunto(s)
Antropometría/instrumentación , Fracturas del Fémur/patología , Fracturas del Fémur/cirugía , Monitoreo Intraoperatorio/instrumentación , Osteotomía/instrumentación , Rotación , Sesgo , Remodelación Ósea , Hilos Ortopédicos , Cadáver , Fracturas del Fémur/fisiopatología , Humanos , Modelos Lineales , Postura , Reproducibilidad de los Resultados , Anomalía TorsionalRESUMEN
Computer-assisted simulation of C4-C5, C5-C6, and C6-C7 intervertebral disc space narrowing was performed on 16 anatomic specimen cervical spines to determine the relationship of the cross sectional foraminal areas with the degree of narrowing of the cervical intervertebral disc space. Compared with normal foraminal area values, reduction of 20% to 30% of the foraminal area was found after 1 mm narrowing of the intervertebral disc spaces; reduction of 30% to 40% of the foraminal area was found after 2 mm narrowing of the intervertebral disc space; and reduction of 35% to 45% of the foraminal area was found after 3 mm narrowing of the intervertebral disc space. Statistically significant differences were found among the remaining cross sectional foraminal areas after different degrees of intervertebral disc space narrowing. Compression of the nerve root within the intervertebral foramina after the collapse of the intervertebral disc space cannot be ignored, and an appropriate surgical procedure to maintain the normal height of the disc space is essential. The size of the intervertebral foramen is related directly to the height of the intervertebral disc space. A 3-mm vertical reduction of the intervertebral disc space is associated more frequently with severe narrowing of the neuroforamen.
Asunto(s)
Vértebras Cervicales/anatomía & histología , Disco Intervertebral/anatomía & histología , Anciano , Cadáver , Simulación por Computador , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Biológicos , Síndromes de Compresión Nerviosa/etiología , Síndromes de Compresión Nerviosa/patología , Valores de Referencia , Raíces Nerviosas EspinalesRESUMEN
STUDY DESIGN: Analysis of the anatomic relation of the Magerl, Anderson, and An screws to the spinal nerve. OBJECTIVES: To compare the potential incidence of nerve root (ventral and dorsal ramus) injury caused by the Magerl, Anderson, and An techniques. SUMMARY OF BACKGROUND DATA: Posterior plating with lateral mass screw fixation is a common procedure for managing an unstable cervical spine. Comparative study of the Roy-Camille and Magerl techniques has been reported. However, the risk of nerve root injury for the Anderson and An techniques is not known. METHODS: Three lateral mass screw insertion techniques were performed in this study: Magerl, Anderson, and An. Each technique involved two specimens and 20 screws inserted from C3 through C7. A 20-mm-long screw was used to overpenetrate the ventral cortex. The anterolateral aspect of the cervical spine was carefully dissected to allow observation of the screw-ramus relationship. RESULTS: The overall percentage of nerve violation was significantly higher with the Magerl (95%) and Anderson (90%) techniques than with the An (60%) technique (P < 0.05). The largest percentages of nerve violation for the Magerl, Anderson, and An screws were found at the dorsal ramus (50%), the bifurcation of the ventral dorsal ramus (45%), and the ventral ramus (55%), respectively. CONCLUSIONS: The results of this study indicate that the potential risk of nerve root violation is higher with the Magerl and Anderson techniques than with the An technique.
Asunto(s)
Tornillos Óseos , Vértebras Cervicales/anatomía & histología , Fusión Vertebral/métodos , Nervios Espinales/anatomía & histología , Anciano , Cadáver , Vértebras Cervicales/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Traumatismos de la Médula Espinal/prevención & control , Fusión Vertebral/efectos adversos , Fusión Vertebral/instrumentación , Raíces Nerviosas Espinales/anatomía & histología , Raíces Nerviosas Espinales/lesiones , Nervios Espinales/lesiones , Nervios Espinales/cirugíaRESUMEN
Demonstration of a posterior malleolar fragment on a radiograph of an ankle fracture is important in the diagnosis and evaluation of posterior malleolus fractures. The size and extent of displacement of a posterior malleolar fragment can be evaluated. The diagnosis of non-union of the posterior malleolus is also important because it can lead to failure of reduction of ankle fractures. The authors present a case in which nonunion of the posterior malleolus was diagnosed by an external-rotation lateral view of the ankle. This could not be demonstrated on the AP or the lateral views. Thirteen cadaver feet were then used to study the external-rotation lateral view. A posterior malleolar fracture was created, and the borders of the fracture line were marked with solder wire. The average external rotation angle required to best demonstrate the posterior malleolar fracture was 50 degrees (range, 43 degrees -55 degrees). The actual size of the posterior malleolus fragment was measured and compared to the x-ray measurement. There was a 0.10 correction for the determination of the actual size of the fragment. The unmarked fragment could not be demonstrated on AP and lateral views.
Asunto(s)
Articulación del Tobillo/diagnóstico por imagen , Artrografía/métodos , Fracturas Óseas/diagnóstico por imagen , Huesos Tarsianos/diagnóstico por imagen , Huesos Tarsianos/lesiones , Adulto , Tobillo/diagnóstico por imagen , Articulación del Tobillo/fisiopatología , Cadáver , Fracturas no Consolidadas/diagnóstico por imagen , Humanos , Masculino , RotaciónRESUMEN
Eighteen cadaver feet were used for radiographic evaluation of the calcaneocuboid joint. The articular surface of the cuboid on all specimens was painted with a radiopaque material. Fractures and 1-mm step-off of the fractures were simulated in six specimens. The articular surface line and joint space could be visualized maximally on an oblique radiograph without overlapping structures. The oblique view is good for assessing the extent of the minor fracture-displacement, which is normally obscured by overlapping projections in dorsoplantar and lateral radiographs. If there is any doubt on the routine radiographs or any injury involving the calcaneocuboid joint, an oblique view of the foot should be performed. The early diagnosis and treatment of calcaneocuboid joint injuries may minimize development of posttraumatic degenerative arthritis.
Asunto(s)
Articulaciones Tarsianas/diagnóstico por imagen , Cadáver , Fracturas Óseas/complicaciones , Fracturas Óseas/diagnóstico por imagen , Humanos , Luxaciones Articulares/diagnóstico por imagen , Radiografía/métodos , Articulaciones Tarsianas/lesionesRESUMEN
The surface area, thickness, and composition of the articular cartilage of the peroneocuboid articulation and the location of the synovium were investigated in 15 cadaver foot specimens. The articulations of the medial side of the peroneus longus tendon and lateral side of the cuboid were covered with fibrous and hyaline cartilages, respectively. On the lateral tuberosity of the cuboid, there is a facet that has 79.37+/-20.24 mm2 articular cartilage area with an oval shape to conform to that of the articular surface of the peroneus longus tendon (articular cartilage area, 67.35+/-28.53 mm2) with which it articulates. The mean thickness of the articular cartilage of the peroneus longus tendon and cuboid was 0.34+/-0.08 and 0.52+/-0.07 mm, respectively. The peroneocuboid joint has its own joint capsule. The synovial cavity does not communicate with the sheath of the peroneus longus tendon. Synovial membranes were attached to the margins of the articular surfaces of the cuboid immediately peripheral to the cartilage region.
Asunto(s)
Cartílago Articular/anatomía & histología , Membrana Sinovial/anatomía & histología , Articulaciones Tarsianas/anatomía & histología , Adulto , Anciano , Cadáver , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculos/anatomía & histologíaRESUMEN
Vertebral artery injury is a serious complication during anterior surgery on the cervical spine. However, little information is available in the literature concerning the mechanism of vertebral artery laceration during the procedures of the anterior cervical decompression. In the current study twenty-eight cadavers were dissected to determine the location and relationships of the fibro-ligamentous tissues to the uncinate process, vertebral artery and nerve roots from the C3 to C6 levels. The vertebral artery and nerve root are encased by a fibro-ligamentous band at the level of the intertransverse space. This fibro-ligamentous band is attached to the lateral aspect of the uncinate process and uncovertebral joint, which combines the vertebral artery, nerve root and uncinate process to form a complex or unit. The fibro-ligamentous tissues between the uncovertebral joint and vertebral artery may explain the propensity to vertebral artery laceration during resection of the uncinate process or an osteophyte projecting from the uncovertebral joint. For this reason, the authors recommend that before resection of the uncinate process or uncovertebral joint is performed, it is necessary to thoroughly dissect the fibro-ligamentous tissues off the uncinate process.