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Human Cadavers (human + cadaver)

Distribution by Scientific Domains

Medical Sciences	58%
Life Sciences	31%
2 Other Domains	11%

Selected Abstracts

Robotic Replacement of the Descending Aorta in Human Cadaver

ARTIFICIAL ORGANS, Issue 9 2006
Norihiko Ishikawa
Abstract:, Robot-assisted replacement of the thoracic aorta was performed in a human cadaver. Temporary shunt bypass was established by inserting a left axillary artery catheter and directing it through the aortic arch toward the right femoral artery through the abdominal aorta. The technique utilized the da Vinci surgical system inserted through the 4-cm supramammary working port and two additional thoracoscopic ports. The working port allowed the introduction of an endoscope, endoscopic instruments, and artificial graft and suture materials. The aorta was dissected using the robotic instruments and was clamped with two transthoracic clamps. After transaction of the aorta, a 20-mm polytetrafluoroethylene graft was cut and an end-to-end anastomosis was then performed with running 3-0 Prolene sutures with robotic instruments. The robotic system provides superior optics and allows for enhanced dexterity. Minimally invasive robotic replacement of the descending aorta is an effective procedure and may add benefits for both surgeon and patients. [source]

Use of an Embalming Machine to Create a Central Venous Access Model in Human Cadavers

ACADEMIC EMERGENCY MEDICINE, Issue 2009
Lee Wilbur
Background:, Human cadavers provide an effective model for procedural training; however, inconsistent blood return during central venous cannulation compromises the overall reliability of this procedure. Objective:, To create and quantitatively assess a human cadaver central venous access model using a continuously-run embalming machine. Curriculum:, Emergency medicine (EM) faculty at Indiana University created this model for a procedure lab designed for EM residents. The right femoral artery was identified by superficial dissection and cannulated distally towards the lower leg. This cannula was connected to a Duotronic embalming machine with a solution composed of 16 oz of 24-index fluid and 3 gallons of tap water at a fixed output of 13 pounds per square inch (psi). Next, the left subclavian vein and artery were identified by dissection and each was cannulated with an 18 gauge angiocath connected to a continuous pressure monitor. Pressures (mmHg) in the subclavian vein and artery were measured continuously while study personnel cannulated the left femoral, right subclavian, right supraclavicular, and right internal jugular veins. This model was assessed for dual sessions lasting two hours each with a two hour break in-between. Results:, During the first session, subclavian pressures were measured at 3 mmHg venous and 22 mmHg arterial, increasing to 11 mmHg venous and 27 mmHg arterial during the second session. Residents were able to withdraw at least 5 milliliters at each central venous site in the embalmed cadaver. Conclusions:, We created a reliable and measurable central venous access model in a fresh-frozen human cadaver using a standard embalming machine. [source]

New insights in the vascular supply of the human parotid gland,Consequences for parotid gland-sparing irradiation

HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 7 2010
Marjolein J. van Holten MD
Abstract Background. Xerostomia is caused by irradiation for head and neck cancer, depending on the dose to the parotid gland. To investigate which part of the parotid gland has to be spared with radiotherapy, detailed information about the vascular supply of the parotid gland is necessary. Methods. Arterial vessels of the head of a human cadaver were colored. A 3-dimensional reconstruction of the parotid gland and the arterial vessels was made and analyzed. Results. Five arterial vessels were responsible for the vascular supply of the parotid gland: the posterior auricular artery, 2 branches so far unnamed, the superficial temporal artery, and the transverse facial artery. All arteries were branches off the external carotid artery, and supplied different parts of the parotid gland. Conclusions. This study describes the detailed vascular supply of the human parotid gland. These results may contribute to improve parotid sparing radiotherapy, thus reducing complications such as xerostomia in the future. © 2009 Wiley Periodicals, Inc. Head Neck, 2009 [source]

Assessment of Intraoperative Safety in Transoral Robotic Surgery,

THE LARYNGOSCOPE, Issue 2 2006
Neil G. Hockstein MD
Abstract Introduction: Robotic technology has been safely integrated into thoracic and abdominopelvic surgery, and the early experience has been very promising with very rare complications related to robotic device failure. Recently, several reports have documented the technical feasibility of transoral robotic surgery (TORS) with the daVinci Surgical System. Proposed pharyngeal and laryngeal applications include radical tonsillectomy, base-of-tongue resection, supraglottic laryngectomy, and phonomicrosurgery. The safety of transoral placement of the robotic endoscope and instruments has not been established. Potential risks specific to the transoral use of the surgical robot include facial skin laceration, tooth injury, mucosal laceration, mandible fracture, cervical spine fracture, and ocular injury. We hypothesize that these particular risks of transoral surgery are similar with robotic assistance compared with conventional transoral surgery. Methods: To test this hypothesis, we attempted to intentionally injure a human cadaver with the daVinci Surgical System by impaling the facial skin and pharyngeal and laryngeal mucosa with the robotic instruments and endoscope. We also attempted to extract or fracture teeth and fracture the cadaver's mandible and cervical spine by applying maximal pressure and torque with the robotic arms. Experiments were documented with still and video photography. Results: Impaling the cadaver's skin and mucosa resulted in only superficial lacerations. Tooth, mandible, and cervical spine fracture could not be achieved. Conclusions: Initial experiments performing TORS on a human cadaver with the daVinci Surgical System demonstrate a safety profile similar to conventional transoral surgery. Additionally, we discuss several strategies to increase patient safety in TORS. [source]

Robotic Replacement of the Descending Aorta in Human Cadaver

Use of an Embalming Machine to Create a Central Venous Access Model in Human Cadavers

Partial unilateral absence of the trapezius muscle in a human cadaver

CLINICAL ANATOMY, Issue 5 2001
Jason G. Emsley
Abstract We report here the partial unilateral absence of the trapezius muscle found during dissection. The left trapezius was significantly reduced in size when compared to the right trapezius, especially in its inferior third. Moreover, the existing fibers of the left trapezius inferior to the scapula were only one-third to two-thirds as thick as those on the right. The vertebral attachment of the inferior fibers of the left trapezius was also notably higher than that on the right. Morphometric analysis indicated that the surface area of the left trapezius was approximately 50% that of the right trapezius. Fiber orientation along the left and right trapezius muscles was also markedly different. An examination of nerve supply yielded no apparent anomalies, therefore suggesting that the absence of trapezius has a developmental etiology. Clin. Anat. 5:383,386, 2001. © 2001 Wiley-Liss, Inc. [source]

An Evaluation of a Blind Rotational Technique for Selective Mainstem Intubation

ACADEMIC EMERGENCY MEDICINE, Issue 10 2004
Aaron E. Bair MD
Abstract Objectives: Although rare, massive hemoptysis and major bronchial disruptions are associated with high mortality. Selective ventilation of the uninvolved lung can increase the likelihood of survival. Specialized devices used for single lung ventilation are often not readily available and can be difficult to place in the emergency department. The authors evaluated a blind rotational technique for selective mainstem intubation using either a standard endotracheal tube (ET) or a directional-tip endotracheal tube (DTET). Methods: This was a prospective, randomized trial on 25 human cadavers. The desired side of mainstem intubation was determined by randomization. Each cadaver was used for four ET, four DTET, and four control intubations. In the ET group, the trachea was intubated. The tube was then rotated 90° in the direction of the desired placement and advanced until resistance was met. In the DTET group, the technique was identical, except the trigger was activated to flex the tip during advancement. In the control group, an ET was advanced in neutral alignment until resistance was met. A bronchoscopist blinded to the desired placement determined tube position. Comparison testing was performed using Pearson's chi-square test. Results: When attempting to intubate the left mainstem, use of the ET with the rotational technique was successful 72.3% of the time (95% confidence interval [95% CI] = 57% to 84%). Intubation of the left mainstem using the DTET was successful 68.5% of the time (95% CI = 54% to 81%; p = 0.67). Attempts to selectively intubate the right mainstem using the rotational technique were highly successful in both groups: 94% for the ET (95% CI = 84% to 99%) versus 97.8% for the DTET (95% CI = 89% to 100%). Among controls, the right mainstem was intubated 93% of the time (95% CI = 86% to 97%). Conclusions: In a cadaveric model, the left mainstem bronchus can be selectively intubated with moderate reliability using this rotational technique. Use of a DTET confers no significant advantage. The ability to generalize these findings to living subjects is unknown. [source]

Commodified Cadavers and the Political Economy of the Spectacle,

INTERNATIONAL POLITICAL SOCIOLOGY, Issue 2 2010
Renée Marlin-Bennett
Traveling anatomy exhibitions import plasticized, posed human cadavers and place them on display. We explore the current industry, its history, and the spectacle of anatomy exhibits. The commodification of cadavers is examined as a problem in global political economy. The absence of global rules identifying plastinated cadavers as human remains allows a globalized plastination and exhibition industry. The spectacle of the exhibitions themselves divert attention away from important moral questions about the proper use of human remains and about the provenance of the cadavers used to create plastinates. The absence of global norms and the distraction of spectacle results in a global regime permitting commodification of cadavers. [source]

Bone Strength at Clinically Relevant Sites Displays Substantial Heterogeneity and Is Best Predicted From Site-Specific Bone Densitometry

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 1 2002
Felix Eckstein Ph.D.
Abstract In this study we test the hypotheses that mechanical bone strength in elderly individuals displays substantial heterogeneity among clinically relevant skeletal sites, that ex situ dual-energy X-ray absorptiometry (DXA) provides better estimates of bone strength than in situ DXA, but that a site-specific approach of bone densitometry is nevertheless superior for optimal prediction of bone failure under in situ conditions. DXA measurements were obtained of the lumbar spine, the left femur, the left radius, and the total body in 110 human cadavers (age, 80.6 ± 10.5 years; 72 female, 38 male), including the skin and soft tissues. The bones were then excised, spinal and femoral DXA being repeated ex situ. Mechanical failure tests were performed on thoracic vertebra 10 and lumbar vertebra 3 (compressive loading of a functional unit), the left and right femur (side impact and vertical loading configuration), and the left and right distal radius (fall configuration, axial compression, and 3-point-bending). The failure loads displayed only very moderate correlation among sites (r = 0.39 to 0.63). Ex situ DXA displayed slightly higher correlations with failure loads compared with those of in situ DXA, but the differences were not significant and relatively small. Under in situ conditions, DXA predicted 50-60% of the variability in bone failure loads at identical (or closely adjacent) sites, but only around 20-35% at distant sites, advocating a site-specific approach of densitometry. These data suggest that mechanical competence in the elderly is governed by strong regional variation, and that its loss in osteoporosis may not represent a strictly systemic process. [source]

Maxillary Sinus Elevation Surgery: An Overview

JOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 5 2003
ELIAZ KAUFMAN DDS
ABSTRACT Maxillary sinus elevation surgery was developed to increase the height of bone available for implant placement in the posterior maxilla. The efficacy and predictability of this procedure have been determined in numerous studies. The basic approach to the sinus (Caldwell-Luc operation) involves an osteotomy performed on the lateral maxillary wall, elevation of the sinus membrane, and placement of bone graft material. The graft materials can be categorized into four groups: autogenous bone, allografts (harvested from human cadavers), alloplasts (synthetic materials), and xenografts (grafts from a nonhuman species). These graft materials can be used alone or in combination with each other. Implant placement can occur at the same surgical procedure (immediate placement) or following a healing period of 6 to 9 months (delayed placement). A more conservative approach to the sinus, the osteotome technique, has been described as well. CLINICAL SIGNIFICANCE This article provides an overview of the surgical technique, with emphasis on anatomic considerations, preoperative patient evaluation (clinical and radiographic), indications and contraindications to the procedure, and possible risks and complications. [source]

The Placement of the Human Eyeball and Canthi in Craniofacial Identification

JOURNAL OF FORENSIC SCIENCES, Issue 3 2008
Carl N. Stephan Ph.D.
Abstract:, An accurate understanding of the spatial relationships between the deep and superficial structures of the head is essential for anthropological methods concerned with the comparison of faces to skulls (superimposition) or the prediction of faces from them (facial approximation). However, differences of opinion exist concerning: (i) the position of the eyeball in planes other than the anteroposterior plane and (ii) the canthi positions relative to the bony orbital margins. This study attempts to clarify the above relationships by dissection of a small sample of adult human cadavers (N = 4, mean age = 83 years, s = 12 years). The most notable finding was that the eyeballs were not centrally positioned within the orbits as the more recent craniofacial identification literature expounds. Rather, the eyeballs were consistently positioned closer to the orbital roof and lateral orbital wall (by 1,2 mm on average); a finding consistent with the earlier anatomical literature. While these estimation errors are small ipsilaterally, several factors make them meaningful: (i) the orbital region is heavily used for facial recognition; (ii) the width error is doubled because the eyes are bilateral structures; (iii) the eyes are sometimes used to predict/assess other soft tissue facial structures; and (iv) the net error in facial approximation rapidly accumulates with the subsequent prediction of each independent facial feature. While the small sample size of this study limits conclusive generalizations, the new data presented here nonetheless have immediate application to craniofacial identification practice because the results are evidence based. In contrast, metric data have never been published to support the use of the central positioning guideline. Clearly, this study warrants further quantification of the eyeball position in larger samples and preferably of younger individuals. [source]

Forensic Dental Training in the Dental School Curriculum

JOURNAL OF FORENSIC SCIENCES, Issue 3 2007
Daniel C. Stoeckel D.D.S.
ABSTRACT: This article reviews the literature regarding forensic education in the dental school curriculum and describes an exercise in forensic identification of victims of a mass casualty. Radiographs were made of dentate human cadavers in the gross anatomy laboratory at the Southern Illinois School of Dental Medicine. The jaws were then removed to provide "wet specimens" for the exercise. Several restorations were performed on the cadaver teeth, after which radiographs of the dissected jaws were made. One author wrote up mock dental records for each of the victims. These records included the first set or "premortem" radiographs. Students participating in the exercise were provided with a plane crash scenario, the dental records of the passengers on the manifest, the dissected jaws, and the second set or "postmortem" radiographs. Students were expected to form three teams. The first two teams evaluated the ante-mortem and postmortem dental records. The third team compared the ante-mortem and postmortem records to arrive at identification. The purpose of the exercise was twofold. It introduced dental students to forensic dentistry and emphasized the need for complete and accurate record keeping in the dental office. Several factors lessened the realism of the exercise and made it difficult to reproduce in the future. These included the uniformity of the dental records and the destruction of cadaver material following the exercise. [source]

Transverse sinus septum: A new aetiology of idiopathic intracranial hypertension?

JOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 2 2004
Rathan M Subramaniam
Summary A venographic cryptic stenosis at the junction of middle and lateral third of the transverse sinus has been observed in patients suffering from idiopathic intracranial hypertension. After reviewing the anatomical and embryological literature of the transverse sinus, 20 transverse sinuses were explored (in a pilot study of 10 human cadavers) in order to determine the anatomical basis of this stenosis. The presence of septa of varying sizes was observed. We conclude that the presence of a large septum is one of the causes of venographic cryptic stenosis observed in these patients and might be one of the aetiological factors involved in idiopathic intracranial hypertension. [source]

Biomechanical comparison of a novel multilevel hex-head pedicle screw design with a conventional head design

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 8 2007
Qi Liu
Abstract The objective of the study was to determine the biomechanical effect during insertion of multilevel hex-head design pedicle screws compared to a conventional screw-head design. Eighteen lumbar vertebrae and thoracic vertebrae from human cadavers were instrumented with a novel, multilevel hexagonal head pedicle screw on one side and a conventional head pedicle screw on the contralateral side. Screws were inserted at a constant rate and insertion and removal torques were recorded. A further 14 lumbar and thoracic vertebrae were used to test alterability of screw direction and operational effort required. Electromagnetic sensors recorded the change in angular direction for both screw and screwdriver. The force applied through the insertion screwdriver required to produce the directional change was also recorded. No significant differences were found between the two screw types for insertion or removal torque in either lumbar or thoracic vertebrae. Multilevel hex-head screws had significantly greater directional alterability than conventional head screws in both lumbar and thoracic specimens. Multilevel hex-head screws also required less force applied through the screwdriver than conventional screws to alter direction of screw insertion in both lumbar and thoracic specimens. The multilevel hex-head design did not affect the insertion or removal torque in comparison to a conventional head design. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:1115,1120, 2007 [source]

Longitudinal excursion and strain in the median nerve during novel nerve gliding exercises for carpal tunnel syndrome

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 7 2007
Michel W. Coppieters
Abstract Nerve and tendon gliding exercises are advocated in the conservative and postoperative management of carpal tunnel syndrome (CTS). However, traditionally advocated exercises elongate the nerve bedding substantially, which may induce a potentially deleterious strain in the median nerve with the risk of symptom exacerbation in some patients and reduced benefits from nerve gliding. This study aimed to evaluate various nerve gliding exercises, including novel techniques that aim to slide the nerve through the carpal tunnel while minimizing strain ("sliding techniques"). With these sliding techniques, it is assumed that an increase in nerve strain due to nerve bed elongation at one joint (e.g., wrist extension) is simultaneously counterbalanced by a decrease in nerve bed length at an adjacent joint (e.g., elbow flexion). Excursion and strain in the median nerve at the wrist were measured with a digital calliper and miniature strain gauge in six human cadavers during six mobilization techniques. The sliding technique resulted in an excursion of 12.4 mm, which was 30% larger than any other technique (p,,,0.0002). Strain also differed between techniques (p,,,0.00001), with minimal peak values for the sliding technique. Nerve gliding associated with wrist movements can be considerably increased and nerve strain substantially reduced by simultaneously moving neighboring joints. These novel nerve sliding techniques are biologically plausible exercises for CTS that deserve further clinical evaluation. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:972,980, 2007 [source]

Anatomical information is needed in ultrasound imaging of muscle to avoid potentially substantial errors in measurement of muscle geometry

MUSCLE AND NERVE, Issue 5 2009
Menno R. Bénard MSc
Abstract This study validates two-dimensional (2D) ultrasound measurements of muscle geometry of the human medial gastrocnemius (GM) and investigates effects of probe orientation on errors in these measurements. Ultrasound scans of GM muscle belly were made both on human cadavers (n = 4) and on subjects in vivo (n = 5). For half of the cadavers, ultrasound scans obtained according to commonly applied criteria of probe orientation deviated 15° from the true fascicle plane. This resulted in errors of fascicle length and fascicle angle up to 14% and 23%, respectively. Fascicle-like structures were detectable over a wide range of probe tilt and rotation angles, but they did not always represent true fascicles. Errors of measurement were either linear or quadratic functions of tilt angle. Similar results were found in vivo. Therefore, we conclude that similar errors are likely to occur for in vivo measurements. For all cadavers, at the distal end of GM, the true fascicle plane was shown to be perpendicular to the distal aponeurosis. Using transverse images of GM to detect the curvature of the deep aponeurosis at the distal end of the muscle belly is a simple strategy to help identify the fascicle plane. For subsequent longitudinal imaging, probe alignment within this plane will help minimize measurement errors of fascicle length, fascicle angle, and muscle thickness. Muscle Nerve, 2009 [source]

Biomechanical Strength of Human Nasal Septal Lining: Comparison of the Constituent Layers

THE LARYNGOSCOPE, Issue 8 2005
David W. Kim MD
Abstract Objective/Hypothesis: Nasal septal perforation is a common complication following surgery involving the nasal septum. Septoplasty, septorhinoplasty, and submucosal resection may result in the inadvertent resection of perichondrium, which may predispose the patient to septal perforations. Study Design: Controlled human cadaver study testing the biomechanical strength of the constituent layers of nasal septal lining. Methods: Uniform samples of nasal septal mucosa, perichondrium, and a composite of both layers were obtained from five fresh human cadavers. The mechanical tensile strength of these layers was evaluated and compared with the Instron 4301 Mechanical Testing System (Canton, MA). Results: Mixed-effects regression analysis demonstrated a significant difference in the tensile strength of the three groups (mean values ± SD: mucosa, 662 ± 308 g; perichondrium, 1370 ± 798 g; composite, 2340 ± 1252 g). All three pairwise comparisons among the three groups showed a significant difference in tensile strength. Conclusion: The perichondrial layer imparts the majority of the biomechanical strength to septal lining. Lining flaps containing both perichondrium and mucosa are stronger than flaps with either perichondrium or mucosa alone. Dissection in the subperichondrial plane during septal surgery provides a stronger septal flap and may prevent the development of nasal septal perforation during nasal surgery. [source]

Thoracic paravertebral spread using two different ultrasound-guided intercostal injection techniques in human cadavers

CLINICAL ANATOMY, Issue 7 2010
Tilemachos Paraskeuopoulos
Abstract The continuity between the intercostal and paravertebral space has been established by several studies. In this study, the paravertebral spread of a colored dye was attempted with two different ultrasound-guided techniques. The posterior area of the trunk was scanned with a linear probe between the level of the fifth and the seventh thoracic vertebrae in eleven embalmed human cadavers. In the first technique, the probe was placed transversely below the inferior margin of the rib, and a needle was inserted between the internal intercostal membrane and the pleura. In the second technique, the probe was placed longitudinally at the intercostal space 5 cm lateral to the spinous processes, and the needle was inserted between the internal intercostal membrane and the pleura. In both techniques, 1 ml of methylene blue was injected, and both the intercostal and paravertebral spaces were prepared. In total, 33 injections were performed: 19 with the transverse technique and 14 with the longitudinal technique. Successful spread of the dye to the thoracic paravertebral space was recorded in 89.5% cases using the transverse technique and 92.8% cases using the longitudinal technique. No intrapleural spread of the dye was recorded in either technique. Ultrasound-guided injection into the intercostal space may offer an alternative approach to the thoracic paravertebral space. Clin. Anat. 23:840,847, 2010. © 2010 Wiley-Liss, Inc. [source]

Anatomical observations of the moderator band

CLINICAL ANATOMY, Issue 4 2010
Marios Loukas
Abstract Apical ventricular septal defects are rare pathologies of the ventricular septum. The moderator band, or other large trabeculations, is the major obstacle for the repair of such defects. The aim of our study was to identify and describe variations in the size and anatomy of the moderator band. We studied the right ventricular apical trabeculations in 100 adult human cadavers. Overall, we identified the moderator band in 92% of hearts. In just over two-fifths (42%), the band was a short and thick trabeculation, whereas, in one-eighth (12%), it was long and thick. In just under one-quarter of the hearts (24%), the band was short and thin, whereas it was long and thin in 14% of the hearts. In the remaining eight hearts, we were unable to identify the moderator band. The mean thickness of the band was 4.5 ±1.8 mm, and its mean length was 16.23 ± 2.3 mm, ranging from 11.3 to 24.3 mm. According to these measurements, we were able to classify the band as originating less than 45% of the distance from the tricuspid valve to the apex (closer to tricuspid valve), seen in 12 hearts, between 45 and 55% of the distance from the valve to the apex, seen in 45 hearts, and greater than 55% of this distance (closer to the apex), seen in 39 specimens. We present these data that may prove useful in the setting of the surgical repair of apical ventricular septal defects through the right atrium. Clin. Anat. 23:443,450, 2010. © 2010 Wiley-Liss, Inc. [source]

A radiologic and histologic study of the os peroneum: Prevalence, morphology, and relationship to degenerative joint disease of the foot and ankle in a cadaveric sample

CLINICAL ANATOMY, Issue 6 2009
C. Muehleman
Abstract The present study investigated the prevalence of an os peroneum (OP, a sesamoid bone) in a cadaveric sample and its relationship to the shape of the cuboid tuberosity, and cartilage degeneration at the cuboid tuberosity and in regional joints within the foot (first metatarsophalangeal and calcaneocuboid) and ankle. The fibularis longus tendon of 33 embalmed human cadavers (mean age 81 years) were obtained from the anatomy laboratory. Nineteen of 64 tendons (30%) displayed an OP both radiographically and histologically. The os peronei ranged in size from small spicules to prominent masses: mean area 2.48 mm2 (left) and 2.70 mm2 (right). Histologically, the os peronei were cancellous bone, the largest occupying most of the tendon at the point of contact with the cuboid tuberosity. Fibrocartilage was present at their borders, merging with dense regular fibrous tissue and peritenon. The talocrural, calcaneocuboid, and first metatarsophalangeal joints were examined for cartilage integrity and osteophytes based on an earlier suggestion that there may be an association between degenerative joint disease and endochondral bone formation. There was no statistical correlation between presence of an OP with any of the following parameters: age, gender, body size, cartilage degeneration, or osteophytes within any of the joints examined. Therefore, the presence of an OP does not appear to be associated with increased endochondral ossification or degenerative joint disease. This study does not preclude the possibility that sesamoid bone formation may be associated with biomechanical functions within the foot; thus, future studies may be warranted. Clin. Anat. 22:747,754, 2009. © 2009 Wiley-Liss, Inc. [source]

Patterns of the circumflex femoral arteries revisited

CLINICAL ANATOMY, Issue 2 2007
M.T. Vazquez
Abstract Knowledge of variations of the circumflex femoral arteries is important when undertaking clinical procedures within the femoral region and in hip joint replacement. Since the 19th century, many different patterns have been proposed to classify their origins. This work studied a statistically reliable sample, the lower limbs of 221 embalmed human cadavers (equal right,left and approximately equal sex distributions), and reviewed the previous literature to propose a unified and simple classification that will be useful to clinicians. Statistical comparisons were made using the ,2 test. The medial and lateral circumflex femoral arteries have been classified into three different patterns based on the levels of their origin. Distribution related to sex and side was also studied. Pattern I: Both arteries arose from the deep femoral artery (346 cases, 78.8%). This pattern was more frequent in females, P = 0.01. There was no significant difference between sides. Type Ia, medial circumflex femoral artery origin was proximal to the lateral circumflex femoral artery origin (53.2%); Type Ib, lateral circumflex femoral artery origin was proximal to medial circumflex femoral artery origin (23.4%); Type Ic, both arteries arose from a common trunk (23.4%). Pattern II: One of the arteries arose from the femoral artery and the other from the deep femoral artery (90 cases, 20.5%). Type IIa, the medial circumflex femoral artery arose from the femoral artery (77.8%) and Type IIb, the lateral circumflex femoral artery arose from the femoral artery (22.2%). There were no significant differences between sexes or sides. Pattern III: Both arteries arose from the femoral artery (2 cases, 0.5%). In every disposition there was a significantly higher prevalence of unilateral rather than bilateral occurrence. In one dissection the medial circumflex femoral artery was absent. Awareness of these variations could avoid unexpected injuries. Clin. Anat. 20:180,185, 2007. © 2006 Wiley-Liss, Inc. [source]

Applying circular posterior-hinged craniotomy to malignant cerebral edemas

CLINICAL ANATOMY, Issue 3 2002
H. Traxler
Abstract Malignant brain edemas are often fatal, regardless of whether they are treated conservatively with sedation, blood pressure management, mannitol-therapy, hyperventilation and hypothermia, or non-conservatively with routine trepanation. Unfortunately, temporal trepanation may result in significant brain damage through herniation of the cerebrum at the edges of the trepanation openings. In one case of a 26-year-old male with severe head injury, a circular posterior-hinged craniotomy (CPHC) was performed after an ineffective unitemporal trepanation for evacuation of an acute subdural hematoma. This ultimately successful operation prompted experimental and morphologic investigations on a new surgical procedure for lowering intracranial pressure (ICP). In 12 of 15 human cadavers, an experimentally ICP was lowered by a CPHC with between 9,21 mm of frontal elevation of the calvaria. Using computer simulation, the frontal elevations of the calvaria were "virtually" performed on 3D reconstructions from CT scans of skulls, and the intracranial volume gained was measured with a computer software program. The volume increase of the cranial cavity showed a relatively constant relation to the cranial capacity and was increased by 6.0% (±0.4%) or 78 cm3 with a 10 mm elevation and by 12.4% (±0.7%) or 160 cm3 with a 20 mm elevation. There were no significant differences with skulls of different ages or ethnic origin; however, a significant effect of gender (F = 7.074; P , 0.013) on the gained volume in percent of the cranial capacity for the 20 mm elevation was observed. This difference can be explained by the inverse relationship between volume increase and cranial capacity (r = ,0.507; P , 0.004). Clin. Anat. Month:173,181, 2002. © 2002 Wiley-Liss, Inc. [source]

Fresh-frozen vs. embalmed bone: is it possible to use formalin-fixed human bone for biomechanical experiments on implants?

CLINICAL ORAL IMPLANTS RESEARCH, Issue 5 2009
Ayhan Cömert
Abstract Purpose: As formalin is an extremely reactive electrophilic chemical that reacts with tissues, the purpose of this study was to explore whether formalin fixation could potentially alter the mechanical properties of bone tissue and have an effect on the primary stability measurements of implants. Material and methods: ,3.3 × 8 mm, ,4.1 × 8 mm, and ,4.8 × 8 mm implants were placed on sockets prepared into the anterior surface of the radius of two fresh-frozen human cadavers. The insertion torque of each implant was quantified using a strain-gauged torque-wrench connected to a data acquisition system at a sample rate of 10 KHz, and resonance frequency analysis measurements were also undertaken for each implant. The cadavers were then subjected to embalment with 10% formalin for 3 months, and the same experiments were undertaken on the contra lateral radius of the cadavers. Results: The insertion torques before and after chemical fixation were similar for ,3.3 mm (P>0.05), and higher values were obtained for ,4.1 mm and ,4.8 mm implants after chemical fixation (P<0.05). The resonance frequency analysis values before and after chemical fixation were similar for all implants (P>0.05). Conclusions: Implants have higher insertion torque values in formalin-fixed bone than fresh-frozen human bone, but similar implant stability quotients in both cases. The insertion torque technique can detect the difference between formalin-fixed and fresh-frozen human bone, but resonance frequency analysis cannot. [source]

Which region of the median palate is a suitable location of temporary orthodontic anchorage devices?

CLINICAL ORAL IMPLANTS RESEARCH, Issue 3 2009
20 years, A histomorphometric study on human cadavers aged 1
Abstract Introduction: Endosseus implants can provide a reliable anchorage during orthodontic treatment. The midpalatal structures around the sutura palatina mediana (SPM) are of special interest due to increasing placement of orthodontic implants in this area. Knowledge about the osseous conditions at this site is necessary to predict the expected degree of implant osseointegration. Methods: The upper jaws of 10 human cadavers, aged 15,20 years, were decalcified, and cross-sectional specimens were obtained from four anterior-to-posterior palatal regions for histomorphometric analysis. The analyses focused on the amount of bone and the width of the SPM to determine the anatomical requirements for reliable insertion of palatal implants. Results: Bone density [bone-volume (BV)/ tissue-volume (TV)] in all measured areas was 40,60%. The maximum density was measured at the level of the first premolars (54.9±5.9%) and the least values (44.2±9.6%) were measured at the level of the interconnecting line of the canines. The mean width of the SPM varies from 1.2 to 0.3 mm in different sections of the palate. In the median sagittal plane, the mean values of bone height to nasal cavity reached >5 mm as far as the level distal of the second premolars. Bone height 2 mm paramedian to the SPM decreased consistently from anterior (4.3±0.9 mm) to posterior (2.5±0.8 mm). Conclusions: Our results indicate that the amount and quality of bone along the anterior palatal midline in 15-to-20-year olds is sufficient for orthodontic implantation. Even implantation posterior to the recommended first premolar level, at which orthodontic implants are most often placed, may be suitable. There are some limitations, however, due to small number of samples and variations of anatomical structures. [source]

Human ex vivo bone tissue strains around immediately loaded implants supporting maxillary overdentures

CLINICAL ORAL IMPLANTS RESEARCH, Issue 6 2005
vanç Akça
Abstract Purpose: To evaluate ex vivo bone tissue strains around maxillary implants supporting immediately loaded bar-retained overdentures. Material and methods: Ninety degree two-element rosette strain gauges were bonded on the labial bone of four ITI® dental implants placed in the maxillary anterior region of four completely edentulous maxilla of fresh human cadavers. The installation torque value (ITV) of each implant was measured by a custom-made torque wrench and resonance frequency analyses (RFAs) were undertaken. A bar-retained overdenture was fabricated for each cadaver, and two miniature load cells were integrated in the first molar region of the overdentures for controlled loading experiments. Strain measurements were performed at a sample rate of 10 kHz and under a maximum load of 100 N, simultaneously monitored from a computer connected to a data acquisition system. Finally, removal torque values (RTVs) of the implants were measured. Results: RFA values did not mirror ITVs, while RTVs of implants were slightly lower than the ITVs. Any correlation could not be obtained between RFA values and ITVs or RTVs. Maximum strains around loaded implants ranged between ,100 and ,550 ,, under 25,100 N. The axial and lateral strain values of posterior implants of both sides were higher than those of anterior implants under all loads (P<0.05). Conclusion: Because occlusal forces in humans tend to decrease because of age-related factors, maximum strains around immediately loaded implants supporting maxillary overdentures fall within physiologic levels. Résumé Le but de cette étude a été d'évaluer les tensions du tissu osseux ex vivo autour d'implants maxillaires portant des prothèses amovibles retenues sur une barre placée immédiatement après l'insertion des implants. Deux jauges de force en rosette à 90° ont été attachées au côté lingual de l'os de quatre implants dentaires ITI® placés dans la région antérieure du maxillaire de quatre cadavres humains frais aux maxillaires édentées. La valeur du couple de torsion lors de l'installation (ITV) de chaque implant a été mesurée par un couple fabriqué et des analyses de fréquence de résonnance (RFA) ont été faites. Une prothèse retenue par une barre a été fabriquée pour chaque cadavre et deux cellules de charge miniatures ont été intégrées dans la région de la première molaire de ces prothèses pour les expériences de charge contrôlées. Les mesures de force ont été effectuées à un taux d'échantillonnage de 10 kHz et sous une charge maximale de 100 N, suivies simultanément par un ordinateur connectéà un système d'acquisition de données. Finalement les valeurs des couples de torsion à l'enlèvement (RTV) des implants ont été mesurées. Les valeurs RFA n'étaient pas en ligne avec les ITV tandis que les RTV des implants étaient légèrement inférieurs aux ITV. Aucune corrélation n'a pûêtre établie entre les valeurs RFA et ITV ou RTV. Les forces maximales autour des implants chargés s'étalaient de ,100 ,e à,550 ,e sous 25 N à 100 N. Les valeurs des forces axiales et latérales des implants postérieurs des deux côtés étaient supérieures à celles des implants antérieurs sous toutes les charges (P<0.05). Zusammenfassung Ziel: Es war das Ziel dieser Arbeit, an bis vor kurzem vitalen Knochengewebe Spannungen um Oberkieferimplantate zu untersuchen, welche sofortbelastete und stegverankerte Hybridprothesen tragen. Material und Methoden: Auf den labialen Knochen von vier ITI-Implantaten in der vorderen Region des zahnlosen Oberkiefers von vier frisch verstorbenen Menschen klebte man Dehnmessinstrumente an. Man mass den Wert der Eindrehkraft (ITV) jedes einzelnen Implantates mit einem handelsblichen Drehmomentschlssel und fhrte eine Resonanzfrequenzanalyse (RFA) durch. Man stellte fr jede Leiche eine stegverankerte Hybridprothese her und man baute in der Region der ersten Molaren zwei kleine Messgerte ein, die kontrollierte Belastungsexperimente erlaubten. Dehnmessungen fhrte man mit einer Frequenz von 10 kHz und einer maximalen Belastung von 100 N durch, simultan aufgezeichnet von einem mit dem Messsystem verbundenen Komputer. Schliesslich mass man auch die Krfte, die es brauchte um die Implantate wieder auszudrehen (RTV). Resultate: Die RFA wiederspiegelte die ITV-Werte nicht, whrenddem die RTV-Werte der Implantate geringfgig tiefer waren als die ITV-Werte. Man konnte weder zwischen der RFA, den ITV-Werten oder den RTV-Werten eine Korrelation herstellen. Die maximalen Dehnungen um die Implantate erreichte Werte zwischen ,100 E und ,550 E bei einer Belastung zwischen 25 N und 100 N. Die axialen und lateralen Dehnkrfte bei posterioren Implantaten waren unter smtlichen getesteten Belastungen beidseits grsser als diejenigen der anterioren Implantate (P<0.05). Resumen Propósito: Evaluar las tensiones del tejido óseo ex vivo alrededor de implantes maxilares soportando sobredentaduras retenidas por barras con carga inmediata. Material y Métodos: Se pegaron dos indicadores de tensión de roseta de dos elementos de 90° en el hueso labial de cuatro implantes dentales ITI® colocados en la región maxilar anterior de cuatro maxilares completamente edéntulos de cadáveres humanos frescos. Se midió el valor del torque de instalación (ITV) de cada implante por medio de una chicharra de torque hecha a medida y se llevó a cabo análisis de frecuencia de resonancia (RFA). Se fabricó una sobredentadura retenida por barras para cada cadáver y se integraron dos células miniatura de carga en la región del primer molar de las sobredentaduras para los experimentos de carga controlada. Se llevaron a cabo mediciones de la tensión a un índice de muestra de 10 kHz y bajo una carga máxima de 100 N, simultáneamente monitorizada desde un ordenador conectado a sistema de adquisición de datos. Finalmente, se midieron los valores del torque de remoción (RTV) de los implantes. Resultados: Los valores de RFA no se reflejaron en los ITVs, mientras que los RTVs de los implantes fueron ligeramente más bajos que los ITVs. No se pudieron obtener correlaciones entre los valores de RFA y los ITVs o RTVE. Las tensiones máximas alrededor de los implantes cargados variaron entre ,100 ,, y ,550 ,, bajo 25 N a 100 N. Los valores de las tensiones axiales y laterales de los implantes posteriores de ambos lados fueron mayores que aquellos implantes anteriores bajo todas las cargas (P<0.05). [source]

Incision design in implant dentistry based on vascularization of the mucosa

CLINICAL ORAL IMPLANTS RESEARCH, Issue 5 2005
Johannes Kleinheinz
Abstract Objectives: The delivery of an adequate amount of blood to the tissue capillaries for normal functioning of the organ is the primary purpose of the vascular system. Preserving the viability of the soft tissue segment depends on the soft tissue incision being properly designed in order to prevent impairment of the circulation. A knowledge of the course of the vessels as well as of their supply area are crucial to the decision of the incision. The aim of this study was to visualize the course of the arteries using different techniques, to perform macroscopic- and microscopic analyses, and to develop recommendations for incisions in implant dentistry. Material and methods: The vascular systems of seven edentulous human cadavers were flushed out and filled with either red-colored rubber bond or Indian ink and formalin mixture. After fixation a macroscopic preparation was performed to reveal the course, distribution and supply area of the major vessels. In the area of the edentulous alveolar ridge specimens of the mucosa were taken and analyzed microscopically. Results: The analyses revealed the major features of mucosal vascularization. The main course of the supplying arteries is from posterior to anterior, main vessels run parallel to the alveolar ridge in the vestibulum and the crestal area of the edentulous alveolar ridge is covered by a avascular zone with no anastomoses crossing the alveolar ridge. Conclusion: The results suggest midline incisions on the alveolar ridge, marginal incisions in dentated areas, releasing incisions only at the anterior border of the entire incision line, and avoidance of incisions crossing the alveolar ridge. Résumé Fournir une quantité adéquate de sang aux capillaires pour un fonctionnement normal de l'organe est le but premier du système vasculaire. Préserver la viabilité du segment de tissu mou dépend de l'incision du tissu mou qui doit être effectuée de manière précise pour prévenir la détérioration de la circulation. Une connaissance de géographie des vaisseaux ainsi que de leurs aires de réserve sont essentiels pour la décision de l'incision. Le but de cette étude a été de visualiser les artères en utilisant différentes techniques afin d'effectuer des analyses tant macro- que microscopiques et pour developper des recommandations pour les incisions lors de la pose d'implants dentaires. Les systèmes vasculaires de sept cadavres humains édentés ont été vidés et remplis avec soit de l'encre de Chine ou une solution rouge et du formol. Après fixation une préparation macroscopique a été effectuée pour mettre en évidence le cours, la distribution et l'aire de réserve des principaux vaisseaux. Dans la zone du rebord alvéoaire édenté des spécimens des muqueuses ont été prélevés et analysés microscopiquement. Les analyses ont mis en évidence les principaux caractères de la vascularisation de la muqueuse. Le cours principal des artères converge de l'arrière vers l'avant, les vaisseaux principaux courent parallèlement au rebord alvéolaire dans le vestibule et l'aire crestale des rebords alvéolaires édentés et sont couverts par une zone non-vascularisée sans anastomose traversant le rebord alvéolaire. Ces résultats suggèrent donc des incisions au milieu de la ligne du rebord alvéolaire, des incisions marginales dans les zones dentées, des incisions d'accès seulement dans la frontière antérieure de la ligne d'incision générale et l'abstention d'incision traversant la crête alvéolaire. Zusammenfassung Ziele: Das erste Ziel des Gefässsystems ist es, eine adäquate Menge Blut zu den Kapillaren zu führen, um eine normale Funktion des Organs zu gewährleisten. Der Erhalt der Lebensfähigkeit des Weichteilsegments hängt von der Weichgewebsinzision ab, welche sauber gestaltet sein sollte, um die Zirkulation nicht zu beeinträchtigen. Die Kenntnis des Verlaufs und der Versorgungsgebiete der Gefässe ist für die Wahl der Inzision entscheidend. Das Ziel dieser Studie war, den Verlauf der Arterien mittels verschiedener Techniken sichtbar zu machen, um makroskopische und mikroskopische Analysen durchführen zu können und um Empfehlungen für Inzisionen in der oralen Implantatchirurgie zu entwickeln. Material und Methoden: Das Gefässsystem von 7 zahnlosen menschlichen Kadavern wurde ausgespült und entweder mit rot gefärbter Gummiflüssigkeit oder mit indischer Tinte und einer Formalinmixtur aufgefüllt. Nach der Fixierung wurde eine makroskopische Präparation durchgeführt, um den Verlauf, die Verteilung und die Versorgungsgebiete der grossen Gefässe aufzuzeigen. Im Bereich des zahnlosen Alveolarkammes wurden Proben der Mukosa entnommen und mikroskopisch analysiert. Resultate: Die Analysen zeigten die generellen Eigenschaften der Vaskularisation von Schleimhäuten. Die Hauptrichtung der versorgenden Gefässe verläuft von posterior nach anterior, die Hauptgefässe liegen parallel zum Alveolarkamm im Vestibulum und die Kammregion des zahnlosen Alveolarkammes wird durch eine avaskuläre Zone ohne den Alveolarkamm überkreuzende Anastomosen bedeckt. Schlussfolgerung: Aufgrund der Resultate werden Inzisionen im Bereich der Kammmitte des zahnlosen Alveolarkammes und marginale Inzisionen im bezahnten Bereich vorgeschlagen. Entlastungsschnitte sollten nur an der anterioren Grenze der gesamten Inzisionslinie gelegt werden. Inzisionen, welche den Alveolarkamm überkreuzen, sollten vermieden werden. Resumen Objetivos: El suministro de una cantidad adecuada de sangre a los capilares tisulares para el funcionamiento normal de un órgano es el propósito primario del sistema vascular. La preservación de la viabilidad del segmento de tejido blando depende en la incisión del tejido blando que debe estar debidamente diseñada en orden a prevenir mermas en la circulación. Un conocimiento del curso de los vasos al igual que del área de suministro es crucial para la decisión de la incisión. La intención de este estudio fue visualizar el curso de las arterias usando diferentes técnicas, para realizar análisis macro- y microscópicos, y desarrollar recomendaciones para incisiones en odontología de implantes. Material y métodos: Se vaciaron los sistemas vasculares de 7 cadáveres humanos edéntulos y rellenados con pegamento de goma de color rojo o con una mezcla de tinta india y formalina. Tras la fijación se llevó a cabo una preparación macroscópica para revelar el curso, distribución y área de suministro de los vasos principales. En el área de la cresta alveolar edéntula se tomaron especímenes y se analizaron microscópicamente. Resultados: Los análisis revelaron las principales características de la vascularización mucosa. El curso principal de las arterias de suministro as desde posterior a anterior, los vasos principales corren paralelos a la cresta alveolar en el vestíbulo y el área crestal de la cresta alveolar esta cubierta por una zona avascular sin anastomosis que crucen la cresta alveolar. Conclusión: Los resultados sugieren incisiones en la cresta alveolar, incisiones marginales en áreas dentadas, incisiones liberadoras solo en el borde anterior de la línea completa de incisión, y evitar las incisiones que crucen la cresta alveolar. [source]