Background: Metacarpophalangeal (MCP) joint dislocations are the result of a hyperextension injury. Complex MCP joint dislocations-those that are irreducible to closed maneuvers and require surgical intervention-are considered uncommon, even in the pediatric population. Although several structures have been identified that contribute to irreducible dislocations, the volar plate is the most significant barrier to reduction through interposition into the MCP joint. Key differences that require consideration for MCP joint dislocations in pediatric patients include ligamentous laxity, the absence of sesamoid bones, the possibility for cartilage fractures, and the possibility of growth arrest. Open surgical intervention for a complex MCP joint dislocation is performed through either the volar or dorsal approach. Controversy exists about which approach is superior. Case Report: We present the case of a 7-year-old female who sustained a complex MCP joint dislocation of the index finger. After numerous unsuccessful attempts at closed reduction, the patient underwent open reduction through the dorsal approach. The phalangeal head had buttonholed through the volar plate and was reduced by using a Freer elevator as a lever and applying gentle traction and flexion. At 4-week follow-up, the patient was pain-free and had regained nearly full range of motion of the index finger MCP joint. Conclusion: In addition to the classic volar and dorsal approaches, different techniques have been used to reduce complex dislocations in pediatric patients, including arthroscopic surgery, a percutaneous technique with manipulation of a skin hook, and a percutaneous technique with a dorsal incision. As demonstrated in this case, open reduction through the dorsal approach remains a viable treatment option for complex MCP joint dislocations in the pediatric population.

Two highly branched glucose polymers with similar structures--starch and glycogen--have important relations to human health. Slowly digestible and resistant starches have desirable health benefits, including the prevention and alleviation of metabolic diseases and prevention of colon cancer. Glycogen is important in regulating the use of glucose in the body, and diabetic subjects have an anomaly in their glycogen structure compared with that in healthy subjects. This paper reviews the biosynthesis-structure-property relations of these polymers, showing that polymer characterization produces knowledge which can be useful in producing healthier foods and new drug targets aimed at improving glucose storage in diabetic patients. Examples include mathematical modeling to design starch with better nutritional values, the effects of amylose fine structures on starch digestibility, the structure of slowly digested starch collected from in vitro and in vivo digestion, and the mechanism of the formation of glycogen α particles from β particles in healthy subjects. A new method to overcome a current problem in the structural characterization of these polymers using field-flow fractionation is also given, through a technique to calibrate evaporative light scattering detection with starch.

Background: Bertolotti syndrome is the association of lumbosacral transitional vertebrae and low back pain or sciatica. Lumbosacral transitional vertebrae are vertebrae with large transverse processes that (1) articulate or fuse with the sacrum or ilium and (2) have a caudal disc space. Bertolotti syndrome is relatively common, with an incidence of 4.6% to 7% in patients with low back pain. The exact etiology of Bertolotti syndrome remains uncertain, although several hypotheses have been proposed. Case Report: A 17-year-old male presented with a long history of low back pain refractory to conservative treatment including medications, activity modification, and physical therapy. Unilateral Bertolotti syndrome was suspected. The diagnosis was confirmed with bupivacaine injection at the transitional articulation. The patient was treated with surgical resection of his enlarged left-sided L5 transverse process, resulting in complete resolution of pain. Conclusion: Lumbosacral transitional vertebrae are relatively common, so Bertolotti syndrome should be on the list of differential diagnoses for low back pain.