In vivo strain in cranial sutures: the zygomatic arch.

Although cranial sutures presumably play a role in absorbing and/or transmitting loads applied to the skull, loading patterns on facial sutures are poorly understood. The zygomatic arch provides a comparatively isolated mechanical part of the skull containing a single suture, the zygomatico-squamosal. In pigs the zygomatico-squamosal suture has a short vertical segment located within the postorbital process and a longer horizontal segment which extends posteriorly. In anesthetized pigs single-element high-elongation strain gages were bonded over both segments of the suture. Strain was recorded during stimulation of the masseter muscles and while the lightly anesthetized animals masticated food pellets. The predominant strain patterns differed in the two segments of the suture. During mastication compressive strains predominated in the vertical segment, but tensile strains predominated in the horizontal segment. The same patterns were also produced by stimulation of the ipsilateral masseter muscle. Contraction of the contralateral masseter reversed the strain pattern, but strain levels were low and during mastication such reversals occurred only transiently. The two segments of the suture have contrasting morphologies. The vertical segment has broad, interdigitating contacts with fibers arranged in a compression-resisting orientation. The horizontal segment has a simple tongue and groove structure with fibers arranged to resist tension. Thus, the structure of the suture reflects the predominant strain pattern.     

Adiposis dolorosa (Dercum's disease): liposuction as an effective form of treatment

The clinical picture of adiposis dolorosa makes a lasting impression on the examining physician. The patient is typically an obese, asthenic woman who appears to have a low pain threshold. She has an unusual distribution of fatty tumors, and her complaint of pain in these tumors seems out of proportion to the physical findings. Alcoholism, emotional instability, and depression are common, and narcotic pain medicine is frequently requested. The patient is easily dismissed as a malingerer after a brief examination. However, liposuctioning of the painful fatty tumors appears to be both practical and effective. While adiposis dolorosa is an unusual disease, it is one that plastic surgeons can recognize and treat.