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Current forensic analysis of blunt force trauma relies on the use of cadaveric or animal tissues, posing ethical and reproducibility concerns. Artificial substitutes may help overcome such issues. However, existing substitutes exhibit poor anatomic and mechanical biofidelity, especially in the choice of skull simulant material. Progress has been made in identifying materials that have similar mechanical properties to the human skull bone, with the potential to behave similarly in mechanical loading. To compare the biomechanical properties of the human calvarial bone with an epoxy resin–based simulant material. Data collected was also used to analyse the effect of periosteal attachment on the mechanical properties of skull bone compared with that of the counterpart samples. Fifty-six human skull bone specimens were prepared from two cadaveric heads. Half of these specimens were removed of periosteum and dura mater as the PR (periosteum removed) group, whereas periosteum was left attached in the PA (periosteum attached) group. Duplicates of the bone specimens were fabricated out of an epoxy resin and paired in corresponding PR and PA groups. The specimens were loaded under three-point bending tests until fracture with image-based deformation detection. Comparison of the epoxy resin and skull specimens yielded similarity for both the PR and PA groups, being closer to the PA group (bending modulus resin PR 2665 MPa vs. skull PR 1979 MPa, resin PA 3165 MPa vs. skull PA 3330 MPa; maximum force resin PR 574 N vs. skull PR 728 N, resin PA 580 N vs. skull PA 1034 N; strain at maximum force resin PR 2.7% vs. skull PR 5.1%, resin PA 2.3% vs. skull PA 3.5%, deflection at maximum force resin PR 0.5 mm vs. skull PR 0.8 mm, resin PA 0.5 mm vs. skull PA 1.0 mm). Bending strength was significantly lower in the resin groups (resin PR 43 MPa vs. skull PR 55 MPa, resin PA 44 MPa vs. skull PA 75 MPa). Moreover, the correlations of the mechanical data exhibited closer accordance of the PR group with the epoxy resin compared with the PA group with the epoxy resin. The load-deformation properties of the epoxy resin samples assessed in this study fell within a closer range to the skull specimens with PR than with PA. Moreover, the values obtained for the resin fall within the reference range for skull tissues in the literature suggesting that the proposed epoxy resin may provide a usable artificial substitute for PA but does not totally represent the human skull in its complex anatomical structure.

With increasingly detailed imaging and mechanical analysis, modalities need arises to update methodology and assessment criteria for skull bone analysis to understand how bone microarchitecture and the presence of attached tissues may affect the response to mechanical load. The main aim was to analyze the effect of macroscopic and microstructural features, as well as periosteal attachment, on the mechanical properties of human skull bone. Fifty-six skull specimens from ethanol-phenoxyethanol-embalmed cadavers were prepared from two human cadavers. Assuming symmetry of the skull, all samples from one-half each were stripped of periosteum and dura mater, while the soft tissues were kept intact on the remaining samples on the contralateral side. The specimens were analyzed using microcomputed tomography to assess trabecular connectivity density, total surface area, and volume ratio. The specimens were loaded under three-point bend tests until fracture with optical co-registration. The bone fragments were then lyophilized to measure their water content. With increasingly detailed imaging and mechanical analysis modalities, there is a need to update methodology and assessment criteria for skull bone analysis to understand how the bone microarchitecture and the presence of attached tissues may affect the response to mechanical load. The mechanical properties were negatively correlated to bone thickness and water content. Conversely, most microarchitectural features did not influence either mechanical parameter. The correlation between mechanical response data and morphologic properties remains similar between the results of embalmed tissues presented here and fresh osseous tissue from literature data. The findings presented here add to the existing methodology to assess human skull for research purposes. The interaction between most microarchitectural features in ethanol-phenoxyethanol-embalmed embalmed skull samples and bending stress appear to be minute.

The importance of the tubed graft cannot be overemphasized in reconstructive surgery of the face and neck. Tubed grafts when properly performed result in excellent cosmetic improvement. Better results than can be obtained by the use of free full thickness grafts should compensate the patient for the greater period of disability. This combination of relatively simple operations under local anesthesia should relieve the patient of a disfigurement which has been a source of mental anguish and an economic handicap for years. The multiple-stage tubed graft procedure while covering a long period of time, actually requires little more hospitalization than the average major surgical procedure, and the loss in time is usually of relatively little economic importance to the patient.

In amebic abscess of the liver the two procedures, emetine without drainage, and incision and drainage, have a definite place in a small percentage of cases, yet the routine adoption of aspiration plus emetine, unless contradictions are present, is the most satisfactory method both from the surgeon's and the patient's viewpoint, and is a life-saving procedure. The use of iodized oil for injection into the amebic cavity immediately following aspiration definitely localizes the abscess, giving its relations to other anatomical parts and making later aspiration or later incision and drainage much easier. The importance of immediate roentgen-rays in two planes must be emphasized, as the iodized oil may not be visible after forty-eight hours. It is important that emetine and ipecac not only be given during the acute stage, but during and following convalescence if recurrences are to be avoided. The absence of ameba or cysts in the stools cannot be taken as an index of cure in hepatic involvement of the liver, and treatment should be continued at intervals over a period of months.

Summary A case of intussusception due to an intraluminal lipoma of the terminal ileum is reported. Benign tumors of the small intestine are rare, occurring only slightly more than half as frequently as malignant tumors of the small intestine. The preoperative diagnosis may be made by x-ray and by the symptoms of partial obstruction or intussusception in an adult, and the findings of a palpable, mobile tumor mass within the abdominal cavity. The treatment is surgical and should be done promptly if signs of intussusception or acute intestinal obstruction are present.

Compression fractures of the bodies of the vertebrae due to forced hyperflexion of the spine are of common occurrence. They are usually the result of a fall from a height or of other severe trauma. Because fractures of the vertebrae are usually associated with severe trauma, many fractures are overlooked if there is no history of a severe trauma or if there are no neurologic symptoms. Owing to the fact that fractures of the vertebrae occur as a result of sudden hyperextension and of extreme muscular action, and in the absence of any apparent severe trauma, they are frequently not diagnosed but are treated as back strain or sacro-iliac strain. Frequently, when there is a history of so slight a trauma and little objective and subjective evidence of injury, a roentgenogram may seem to some an unnecessary expense. Such cases are treated as back strain over a period of months

Umbilical fistulas derived from remnants of the urachus are rare, particularly in adults. Four cases of pathologic conditions originating in the urachus, seen at the U. S. Marine Hospital, Staten Island, during the past five years are reported. One was a malignant growth, the other three cases were chronic fistulas. At birth the urachus reaches to the umbilicus. Normally, after birth the bladder descends, taking the urachus with it, leaving only a fibrous tissue cord. In the normal adult the urachus measures from 3 to 10 cm. in length and reaches only one third the distance from the apex of the bladder to the umbilicus, being attached at the umbilicus only by fibrous cords from the obliterated umbilical arteries. In a small percentage of cases, however, such descent of the urachus does not occur, and there remains a more or less obliterated epithelial structure reaching from the umbilicus to the