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Cytosine-phosphate-guanine (CpG) preconditioning reprograms the genomic response to stroke to protect the brain against ischemic injury. The mechanisms underlying genomic reprogramming are incompletely understood. MicroRNAs (miRNAs) regulate gene expression; however, their role in modulating gene responses produced by CpG preconditioning is unknown. We evaluated brain miRNA expression in response to CpG preconditioning before and after stroke using microarray. Importantly, we have data from previous gene microarrays under the same conditions, which allowed integration of miRNA and gene expression data to specifically identify regulated miRNA gene targets. CpG preconditioning did not significantly alter miRNA expression before stroke, indicating that miRNA regulation is not critical for the initiation of preconditioning-induced neuroprotection. However, after stroke, differentially regulated miRNAs between CpG- and saline-treated animals associated with the upregulation of several neuroprotective genes, implicating these miRNAs in genomic reprogramming that increases neuroprotection. Statistical analysis revealed that the miRNA targets were enriched in the gene population regulated in the setting of stroke, implying that miRNAs likely orchestrate this gene expression. These data suggest that miRNAs regulate endogenous responses to stroke and that manipulation of these miRNAs may have the potential to acutely activate novel neuroprotective processes that reduce damage.

Background: Suture anchors have been developed for the fixation of ligaments, capsules, or tendons to bone. These devices have led to improved fixation, smaller incisions, earlier limb mobility, and improved outcomes. They were originally developed for use in shoulder reconstructions but are now used in almost all extremities. In the lower leg they are used in the tibia, the talus, the calcaneus, tarsal bones, and phalanges. Nevertheless, techniques for insertion and mechanisms of failure are not well described., Methods: Five suture anchors were studied to determine the pullout strength in four distal cadaver femurs and four proximal cadaver tibias from 55- and 62-year-old males. Eight hundred ninety Newton line was used, testing the anchors to failure with an Instron testing device (Instron, Norwood, MA). The anchor devices were inserted randomly and tested blindly (12 tests per anchor device, 60 tests in all)., Results: Two anchors in each group tested failed at low loads. Both types of plastic anchors had failures at the eyelet. Average pullout strength varied from 85.4 to 185.6 N., Conclusions: Insertion techniques are specific for each device, and they must be followed for optimal fixation. In this study, in all five groups of anchors tested two of the 12 anchors in each group failed with minimal force. On the basis of this finding we recommend that, if suture anchor fixation is necessary, at least two anchors should be used. Since there appears to be a percentage of failure in all devices, the second anchor can serve as a backup. It is imperative that surgeons be familiar with the insertion techniques of each device before use.

Background: Proprioceptive deficiencies, peroneal muscle weakness, varus hindfoot, and varus tibial plafond have each been implicated as a predisposing factor in recurrent ankle instability. Another predisposing factor for instability is a position of the fibula posterior to the transverse axis of the talus. This study examined the relationship of fibular position and ankle instability with anatomic dissection and magnetic resonance imaging (MRI)., Methods: Data were obtained from 100 consecutive MRI scans of adult ankles: the malleolar index in degrees and the fibular position anterior or posterior to the anteromedial malleolar plane and relative to the transverse axis of the talus. Twenty cadaver ankles also were studied by MRI and then by anatomic dissection. The malleolar index, the talar length, and the length of the anterior talofibular (ATF) ligament were recorded., Results: The MRI study showed that variation of the malleolar index ranged from 2 to 30 degrees. There was no correlation between the malleolar index and the talar length or the length of the ATF ligament., Conclusions: There is a bell-shaped curve of variation of the position of the fibula relative to the transverse axis of the talus. An ankle mortise with a more posteriorly positioned fibula has less structural stability and is more susceptible to sprain. Neither talar length nor ATF ligament length correlated with fibular position.

Treatment of symptomatic large cystic lesions of the talus has had mixed results. A technique of treatment using a cored osteochondral graft taken from the ipsilateral knee is presented. Preliminary results in ten consecutive patients show significant improvement in all patients with an average increase of 27 points in the AOFAS Hindfoot score.

Thirty-five patients undergoing a Bröstrom procedure for ankle instability were studied retrospectively as to the presence or absence of spurs and loose bodies, outcome, and mortise relationships. 100 adult volunteers had their ankles radiographically and clinically examined for spurs, loose bodies, and laxity. 100 patients' ankles with computed axial tomography were examined to define malleolar relationships. The AOFAS Hindfoot scores on the Bröstrom patients with or without spurs were not different. Patients undergoing a Bröstrom procedure had a 3.37 times incidence of spurs and/or loose bodies compared to normal adult population. The incidence of asymmetric but asymptomatic ankle laxity in normal adults was 11%. The fibula has a 38 degree range of position relative to the axis of the talus and the medial malleolus. A posterior fibular position may predispose to injury.

Thirteen patients presenting with symptomatic pathologic variations or congenital deformities of the subtalar joint are presented. These variations included: four abnormal posterior talar processes, five patients with asymmetric subtalar joint development, and four congenital complete subtalar coalitions with a secondary ball-and-socket joint. In each case these adult patients had been unaware of the variation and had been symptom free until "awakening" sprain or fracture trauma brought about symptoms. The nonoperative and operative management of these variations is reviewed.

Between 1977 and 1992, 42 patients were seen who had 51 feet operated upon for bunions in which the surgery failed. A total of 105 procedures were done on these 51 feet until the patients either achieved satisfactory correction (N = 28) or they declined (N = 14) further surgery. An analysis of these failures and review of literature revealed 12 anatomic variations and 7 secondary factors that were seen in association with surgical failure. These findings were correlated with published criteria and our experience with various bunion procedures to advance general indications and contraindications for specific bunion procedures.