Lesser metatarsal osteotomies. A biomechanical approach to metatarsalgia.

As with most other orthopedic conditions, a firm understanding of the normal and pathologic biomechanics of the lesser metatarsals is essential when contemplating treatment of metatarsalgia. Despite its prevalence, metatarsalgia remains a technically demanding surgical challenge. Some of the difficulty with treatment of this problem arises because of some of the controversies discussed previously. Many lesser metatarsal osteotomies have been described, and their success depends on many factors. Alleviating the correct amount of pressure underneath the metatarsal head without adversely affecting the biomechanics of the region demands an exacting osteotomy that is stable and readily heals. Much of the research done to date has not proved which procedure can achieve these goals reproducibly for patients. It is hoped that future investigations will guide treatment choices and allow patients to obtain relief from this difficult problem with greater success.

Maternal polydrug use including cocaine and postnatal infant sleep architecture: preliminary observations and implications for respiratory control and behavior.

Twelve-hour overnight pneumocardiograms were assessed for sleep architecture and sleep efficiency in two groups of healthy term newborn infants: a group exposed prenatally to cocaine alone or in combination with other drugs and a non-exposed group. Sleep was differentiated from wakefulness by an increase in heart rate, an increase in or variation in the duration and amplitude of the respiration and increased artifacts on the heart rate channel. Quiet and active sleep were determined by the regularity or irregularity of heart rate and respiration. In a sub-set of infants, the number of arousals during active sleep was calculated. Overall significance was confirmed by ANOVA followed by paired comparisons using the Student's-test. When compared to non-exposed infants within the first week of life, infants exposed prenatally to cocaine alone or in combination with other drugs demonstrated more wakefulness and less sleep (P < 0.05), more frequent arousals during active sleep (P < 0.01), and the tendency of a higher proportion of active sleep compared to quiet sleep. These findings may have implications to both behavioral and respiratory control findings associated with prenatal cocaine exposure.