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Malignant fibrous histiocytoma and pleomorphic sarcoma in association with medullary bone infarcts.

A malignant fibrous histiocytoma arose in the proimal tibia of a 40-year-old man who had multiple, symmetrically distributed, medullary bone infarcts of unknown etiology, involving the distal femora and the tibiae. Despite amputation and chemotherapy, widespread metastases developed and death occurred 19 months after surgery. A polemorphic sarcoma, probably representing an anaplastic malignant fibrous histiocytoma, arose in association with a single medullary infarct in the proximal humerus of a 33-year-old woman. She remains well without evidence of disease five years after treatment by radical radiotherapy followed by shoulder disarticulation. Sarcoma arising in association with bone infarction is a rare entity. Sixteen cases reported in the medical literature, including our own, are reviewed. The sarcomas arose in the tibia in nine cases, the femur in six cases and the humerus in one case. The patients were usually older individuals and 13 of the 16 were male. All but two had multiple bone infarctions. Four of the patients had caisson disease, three had what is probably an hereditary bone dysplasia, one had sickle cell disease and eight had infarcts of unknown etiology. Most patients have had a rapidly fatal outcome. Thirteen of the sarcomas have been fibrosarcomas or malignant fibrous histiocytomas, both of which are rare primary bone tumors. Analysis of the published cases of bone infarction-related sarcomas suggests that the risk of developing a sarcoma is greatest in infarcts with large medullary components.

Adult↗

Further studies on the carcinogenesis of the colon of the rat with special reference to the absence of intestinal contents.

The proximal and distal ends of the ascending, transverse and descending colon of 67 Sprague-Dawley rats were severed and stitched to the abdominal wall. The remaining colon was anastomosed end to end. The disarticulated colon loop was rinsed 30 times over 15 days to remove all traces of intestinal contents. The animals were then given subcutaneous injections of 1,2-dimethylhydrazine (21 mg/kg body weight) for 27 weeks. During that period, the isolated loops were rinsed with saline once a week. The rats were killed after seven months of treatment. Eighty-five tumors developed in the 67 animals: 20 in the isolated loops and 65 in the end-to-end anastomosed colon. The carcinogen employed reached the colonic loop through the circulation and induced (independently of bile acids) mucosal changes that led to the development of colonic tumors.

1,2-Dimethylhydrazine↗

Variations of rat skull bone robusticity evoked by malnutrition.

Weanling Holtzman rats of both sexes were fed a control (25% protein), a 10% protein, and a 2% protein semisynthetic diet. Protein deficit (PD) and protein calorie malnutrition (PCM) were estimated from comparisons between control and 10% protein, and control and 2% protein-fed animals, respectively. Animals were killed when they were 56 days old and their skulls cleaned and disarticulated. Individual bones and incisors were ovendried to constant weight. Total weight (TW), maximal projected length (MPL), and robusticity index (RI) were determined on each bone and incisor. It was found that all the bones and incisors did not behave uniformly. They followed two main patterns: (1) Proportional variation. RI values were not affected by nutritional deficiencies. All basicranial bones and 4 of 10 facial bones followed this pattern. (2) Non-proportional variation. RI values were affected by nutritional deficiencies. This pattern was subdivided into two trends: (2a) PD-diminished RI values. Both upper and lower incisors and 1 of 10 facial bones followed this trend. (2b) PCM, but not PD, decreased RI values. All vault bones and the remaining five facial bones followed this trend. It was concluded that there was a differential robusticity response among cranial base, calvaria, and incisors. This response may be connected with the differences in both histogenetic characteristics of those components and the functional roles they have to perform. The nonvault intramembranous bones showed a nonspecific behavior. This fact precluded the classification of the facial region in some of the previously defined patterns.

Analysis of Variance↗

Reassessment of the paleoenvironment and preservation of hominid fossils from Hadar, Ethiopia.

Samples of paleosols from locality AL-333, known for numerous specimens of Australopithecus afarensis, were analyzed in order to reconstruct the original soils and environment of burial of the associated fossil hominids. The bones were found in swale-like features, within the calcareous and coarse-grained basal portion of a paleosol. This is more like an assemblage of bones buried during a single depositional episode, such as a flood, than an assemblage accumulated on a soil over a long period of time by carnivores or other means of death. What killed the hominids remains unclear, but considering the association of originally disarticulated bones of such hydraulically distinct types as phalanges and maxillae, it is very likely that they died and partially rotted at or very near this site. The paleosols at AL-333, here named the Fo and Go clay paleosols, have calcareous rhizoconcretions, granular surface horizons, prismatic peds, and shallow calcareous nodules and stringers like soils now supporting grassy woodland in semiarid regions. Although this group of hominids was buried in streamside gallery woodland, there is evidence from Laetoli, Tanzania, that A. afarensis ventured out into open wooded grassland as well. Evidence for this should be sought from other paleosols at Hadar.

Animals↗

Paleohistology of Paget's disease in two medieval skeletons.

Paget's disease has been ascribed several times to specimens of archeological bone but, in the absence of microscopic examination, the evidence remains insubstantial. Suspected metabolic bone disease is described here in the archeological remains of a skeleton from a 16th century burial ground at Wells Cathedral, England and from a single medieval sacrum recovered from a large deposit of disarticulated bones from a churchyard at Barton-on-Humber, England. Radiographs showed apparent structural abnormality in one femoral shaft and calcaneus and in the isolated sacrum. Histomorphometry on undecalcified bone cores confirmed the regions of abnormality and showed not only increased trabecular width but also areas of "mosaic" woven bone together with extensive resorption cavities; these features contrasted with the normal structure and organized lamellar bone from sites elsewhere. Despite post-interment changes in surrounding tissues, the morphological stability of some of the osteocytes was remarkable. Preservation of the histology was sufficient to permit the assignment of a metabolic bone disorder and the nature of the sclerosis was consistent with Paget's disease.

England↗

Cannibalism in Chaco Canyon: the charnel pit excavated in 1926 at Small House ruin by Frank H.H. Roberts, Jr.

A charnel pit that contained the disarticulated and intentionally damaged remains of eight incomplete adult and subadult Anasazi skeletons was found and excavated in 1926 by F.H.H. Roberts, Jr., at an AD 900 ruin he named Small House, located in Chaco Canyon, northwestern New Mexico. Damage includes extensive perimortem cranial and postcranial bone breakage, cut marks, anvil-hammerstone abrasions, burning, many missing vertebrae, and fragment end-polishing. Together, these six types of perimortem damage are believed to be the taphonomic signature of prehistoric Anasazi cannibalism. The possible cause of the Small House episode is discussed within the framework of two explanatory models--random social pathology and institutionalized social control by violent means.

Bone and Bones↗

Robusticity and osteoarthritis at the trapeziometacarpal joint in a Bronze Age population from Tell Abraq, United Arab Emirates.

Osteoarthritis (OA) is a progressive disease of the joints and can cause pain, reduced range of motion and strength, and ultimately loss of function at affected joints. Osteoarthritis often occurs at sites where biomechanical stress is acutely severe or moderate but habitual over the course of a lifetime. Skeletal remains from an Umm an-Nar tomb at Tell Abraq, United Arab Emirates (ca. 2300 BC), were recovered and represented over 300 individuals of all ages. The remains were disarticulated, commingled, and mostly fragmented. An analysis of 650 well-preserved adult metacarpal and carpal bones, from the tomb's western chamber, revealed that over 53% of the trapeziometacarpal joint facets showed signs of OA varying from mild to severe. The first and second metacarpals and trapezium bones were sided and evaluated for OA at the trapeziometacarpal joint articulations. Osteoarthritis was detected on 53% of the first metacarpals, 40% of the second metacarpals, and 57% of the trapezium bones. All specimens appeared enlarged, and the first metacarpals were assessed for sexual identification and robusticity. Eighty-five percent of the bones were probable males, and more than 80% of them had a robusticity index of 60 or higher. A strong correlation was found between OA, sex, and robusticity. High levels of OA and robusticity at the thumb suggest that the people of Tell Abraq were habitually involved in biomechanically challenging work with their hands.

Biomechanical Phenomena↗

Radiography of rabbit articular cartilage with diffraction-enhanced imaging.

Articular cartilage of synovial joints is not visible with conventional X-ray imaging. Hence, the gradual degeneration and destruction of articular cartilage, which is characteristic of degenerative joint diseases, is only detected at a late stage when the cartilage is lost and the joint space that it once occupied narrows. The development of an X-ray imaging technique that could detect both the degenerative cartilage and bone features of joint diseases is of special interest. Here we show, for the first time, that a high-contrast imaging technique, diffraction-enhanced X-ray imaging (DEI), allows the visualization of articular cartilage of both disarticulated and articulated rabbit knee joints. Furthermore, a single cartilage lesion can be visualized within an intact joint. The results suggest that DEI has the potential to be of use in the study of cartilage degeneration.

Animals↗

Through-knee amputation in high-risk patients with vascular disease: indications, complications and rehabilitation.

During a 10-year period 104 patients (mean age 72 years) had 106 through-knee amputations. Indications for surgery were: limb gangrene, 67 (64 per cent); ischaemic ulceration, 22 (21 per cent); rest pain, 9; knee contractures, 6. Thirty patients had had previous unsuccessful vascular reconstructive surgery and five had had a failed femoral embolectomy. The through-knee disarticulation used lateral skin flaps. The mortality was 21 (20 per cent). Of the 83 survivors, 59 (71 per cent) underwent uncomplicated primary wound healing; 36 (43 per cent) of the survivors were unsuitable for rehabilitation on a prosthesis. The remaining 47 (57 per cent) were walking before discharge 30-130 days (mean 68 days) after amputation. Through-knee amputation is a rapid, relatively bloodless, amputation and is a useful debridement procedure. The many surgical and functional advantages, in conjunction with the recent reports of better rehabilitation compared with the above-knee or Gritti-Stokes amputation, suggests that the through-knee amputation deserves greater consideration.

Aged↗

Topography and interactions of the arytenoid and cricoid articular facets: implications for vocal process positional shifts.

Using new computer applications and digital technologies, we provide a rigorous description and realistic illustrations of the arytenoid-on-the cricoid rotations. We also provide the articular facet topography and interactions that underlay those rotations and the concomitant vocal process positional shifts. The thyroid cartilage and all soft tissues were removed from three excised, preserved, normal, adult human larynges without disturbing the crico-arytenoid (CA) articular capsule. Three CA assemblies were thus prepared and used to digitize arytenoid rotations and vocal process positional shifts, and, after disarticulation, also the surface contour of the arytenoid and cricoid facets, and the cricoid lumen margin. The digitized data served to computer generate 2D and 3D graphic visualizations of the vocal process positional shifts, of the topography of the facets, and of the facet motion sequences that show that the anteroposteriorly concave arytenoid facet slides and conjunctly rotates on the anteroposteriorly convex cricoid facet. Visual details of all graphic representations and facet motion sequences were essentially identical across the three assemblies. Then, based on the computer generated data obtained from the largest of the CA assemblies, 3D, realistic, and hand-drawn images were made that illustrate the directions in which the arytenoids can rotate and the vocal processes concomitantly shift positions. Results indicate that when the arytenoids rotate by sliding from anterior to posterior on the cricoid facets about a primary axis of motion aligned from medial, posterior, and superior, to lateral, anterior, and inferior, their vocal processes shift positions along a plane obliquely oriented from anterior and medial, to posterior and lateral, and from inferior and medial, to superior and lateral.

Adult↗

Bilateral tibial hemimelia I.

Congenital absence of tibia is a rare anomaly. We report a case of bilateral tibial hemimelia born to phenotypically normal parents. The two amputated legs with tibial dysplasia obtained from a 3-year-old boy were studied by radiography and anatomical dissection. The radiological evaluation revealed a normal hip joint. The lower end of femur was normal without any bifurcation, shortening or bowing. Fibula was present on both legs and there was no sign of bowing or doubling. Both right and left tibiae were absent. In addition, on the right side, five tarsal bones, two metatarsals and the corresponding digital rays were absent. On the left side, three tarsal bones were absent. Dissection of the amputated segments showed the presence of extensor digitorum longus, peroneus tertius, peroneus longus and brevis, gastrocnemius, and soleus. Following bilateral knee disarticulation the patient was fitted with prosthesis and is doing well.

Amputation, Surgical↗

Hemicorporectomy.

Intractable decubitus ulcers and femoropelvic osteomyelitis are rare sequelae of paraplegia. Therapy for these conditions ranges from the simple to the complex, including wound debridement and care, alimentary and urinary tract diversion, hip disarticulation, and myofasciocutaneous rotational flaps. Should the condition be recalcitrant to these modalities the only curative therapy is hemicorporectomy. A 28-year-old rendered paraplegic 3 years ago presented manifesting sepsis; marasmus; hip and knee flexion contractures; suppurative sacral and femoropelvic decubitus ulcers, exposed bone, and osteomyelitis; and fecal and urinary incontinence. Pre-operative nutritional supplementation, wound debridement and care, and psychological counselling were provided. Hemicorporectomy was performed, including colostomy, ureteroileal conduit, gastrostomy, and translumbar amputation. Several anatomical, physiological, and operative-technical perspectives are emphasized: a two-staged approach may be preferable--at the first setting an intra-peritoneal exploratory celiotomy with alimentary and urinary tract diversion; and at the second setting an extra-peritoneal hemicorporectomy; preservation of abdominal wall musculature and fasciae to facilitate wound closure; sequential and bilateral ligation of the arteriae et venae iliaca communis; translumbar amputation between the fourth and fifth lumbar vertebrae; extirpation of the fourth lumbar processus spinosus vertebrarum; closure of the dura mater and translation of musculi sacrospinalis into the vertebral canal; avoidance of hypervolemia and hyperthermia; avoidance of wound pressure; testosterone replacement therapy for eunuchism; and physical and occupational rehabilitation including adaptation to a customized bucket prosthesis.

Adult↗

Coronary stenting without anticoagulation.

Stents are useful bail-out devices in coronary angioplasty. They are also used electively for situations associated with poor angioplasty results (e.g., restenotic lesions, venous grafts) and may reduce restenosis rates. However, the significant incidence of stent thrombosis necessitated aggressive anticoagulation with associated hemorrhagic complications. This remains a major limitation of stenting. We present our experience of stenting with half (disarticulated) Palmaz-Schatz coronary stents in eight consecutive patients, managed with aspirin alone. No patient experienced acute or subacute stent thrombosis.

Adult↗

Cranial anatomy of the extinct amphisbaenian Rhineura hatcherii (Squamata, Amphisbaenia) based on high-resolution X-ray computed tomography.

The fossilized skull of a small extinct amphisbaenian referable to Rhineura hatcherii Baur is described from high-resolution X-ray computed tomographic (HRXCT) imagery of a well-preserved mature specimen from the Brule Formation of Badlands National Park, South Dakota. Marked density contrast between bones and surrounding matrix and at bone-to-bone sutures enabled the digital disarticulation of individual skull elements. These novel visualizations provide insight into the otherwise inaccessible three-dimensionally complex structure of the bones of the skull and their relationships to one another, and to the internal cavities and passageways that they enclose. This study corrects several previous misidentifications of elements in the rhineurid skull and sheds light on skull construction generally in "shovel-headed" amphisbaenians. The orbitosphenoids in R. hatcherii are paired and entirely enclosed within the braincase by the frontals; this is in contrast to the condition in many extant amphisbaenians, in which a large azygous orbitosphenoid occupies a topologically distinct area of the skull, closing the anterolateral braincase wall. Rhineura hatcherii retains a vestigial jugal and a partially fused squamosal, both of which are absent in many extant species. Sculpturing on the snout of R. hatcherii represents perforating canals conveying sensory innervation; thus, the face of R. hatcherii receives cutaneous innervation to an unprecedented degree. The HRXCT data (available at www.digimorph.org) corroborate and extend previous hypotheses that the mechanical organization of the head in Rhineura is organized to a large degree around its burrowing lifestyle.

Animals↗

Cranial anatomy of the spade-headed amphisbaenian Diplometopon zarudnyi (Squamata, Amphisbaenia) based on high-resolution X-ray computed tomography.

The skull of the trogonophid amphisbaenian Diplometopon zarudnyi is described from high-resolution X-ray computed tomographic (HRXCT) imagery of a whole museum specimen preserved in ETOH. The skull was digitally resliced and disarticulated into individual elements, producing novel visualizations that allow detailed morphological analysis of its three-dimensionally complex structure. The prefrontal and jugal are absent in Diplometopon. The septomaxilla is present but hidden entirely from superficial view. In contrast to previous studies, we recognize a splenial fused to the compound bone of the mandible and a squamosal fused to the otic-occipital complex. Comparison of Diplometopon to the two other amphisbaenians previously described in comparable detail, Rhineura hatcherii and Amphisbaena alba, reveals a mosaic of cranial similarities and differences. Both Diplometopon and Rhineura exhibit a craniofacial angulation and expanded rostral blade related to use of the head as a digging tool, but the detailed architecture of these features is quite different. Additionally, whereas the snout of Rhineura exhibits a high degree of sculpturing and sensory innervation, this is not the case in Diplometopon. Unlike in Rhineura and Amphisbaena, the cranial elements of Diplometopon do not exhibit an extensive degree of overlap or complex interlocking sutures; instead, most of the cranial elements lie in loose apposition to each other. The degree to which this mosaic of features reflects functional demands, shared ancestry, and/or convergence is unclear in the absence of a stable hypothesis of amphisbaenian phylogeny.

Animals↗

Local compression patterns beneath pneumatic tourniquets applied to arms and thighs of human cadavera.

Distributions of tissue fluid pressure were examined beneath a standard pneumatic tourniquet in six upper extremities and six lower extremities of fresh human cadavera, disarticulated at the shoulder and hip, respectively. A standard 8-cm-wide tourniquet cuff was applied at mid-humerus or mid-femur position. Tissue fluid pressures were measured by 100-cm-long slit catheters inserted parallel to the bone at four tissue depths: subcutaneous, subfascial, mid-muscle, and adjacent to bone. All arms and thighs were studied at the following cuff pressures: 100, 150, 200, 250, 300, 400, and 500 mm Hg. Tissue fluid pressure was always maximal in subcutaneous tissue at mid-cuff. Transmission of cuff pressures to deeper tissues was significantly less (p less than 0.01) in the thighs with a girth of 40-52 cm than in the arms with a girth of 22-33 cm. At the four tissue depths studied, tissue fluid pressures fell steeply in a longitudinal direction near the cuff edge to levels near zero at points 1-2 cm outside each cuff edge. Our results suggest that wider cuffs are required on thighs than on arms to provide a bloodless field during limb surgery and to minimize underlying tissue injury associated with high cuff pressures. Our recommendation for wider tourniquet cuffs than those presently used during orthopaedic surgery is contrary to recent prevailing knowledge.

Arm↗

Prevention of ligament and meniscus atrophy by active joint motion in a non-weight-bearing model.

This study describes the effect of active joint motion on the maintenance of ligament and meniscus mass in a non-weight-bearing model of disuse. Denervation and fixation models of immobilization have shown that resorption of isotope and atrophy of mass occurred for hard tissue (bone) and soft tissues (ligament, tendon, or meniscus). A unilateral ankle disarticulation model of disuse that maintains active knee motion without weight bearing was studied for 8 weeks in dogs that were chronically prelabeled with three different isotopes. The effects of non-weight-bearing without denervation or fixation were analyzed for the resorption of isotopes, and net atrophy of bone mass (femur or tibia) and soft-tissue mass (collateral or cruciate ligaments, menisci). A large and similar loss of all three isotopes, as well as collagen and calcium mass occurred for whole femur and tibia; this indicated that mass loss was equivalent to bone resorption and suggests little replacement with new bone. No loss of isotope or mass per whole tissue occurred for the collateral and cruciate ligaments or menisci. The strength of the femur-anterior cruciate ligament-tibia complex was analyzed by a tensile failure test when a fast rate of deformation was applied; the results did not differ qualitatively or quantitatively between control and experimental limbs. The absence of weight bearing for 8 weeks resulted in marked bone atrophy without resorption or atrophy of soft tissues, or decrease of the mechanical strength for the femur-ligament-tibia complex.

Animals↗

Major extremity amputation for nodal metastasis from squamous cell carcinoma.

The regional lymph node basin is usually the first site of spread in cutaneous squamous cell carcinoma (SCC). Regional metastases are usually treated with comprehensive nodal dissection, sometimes followed by radiation and/or chemotherapy. Occasionally, when disease recurs after these conventional therapies, major extremity amputation may be the only way to render patients free of disease. We present three cases for which major extremity amputation was necessary. One patient underwent forequarter amputation for nodal metastasis, which had invaded the brachial plexus. Another patient underwent hip disarticulation for femoral bony invasion from inguinal nodal metastasis. The third patient underwent a hemipelvectomy for nodal metastasis, which had eroded the femoral artery and pelvic bone. These cases show that major extremity amputation can be both palliative and curative in patients with SCC.

Aged↗