The use of a syndesmosis procedure for the treatment of hallux valgus: good clinical and radiological results two years post-operatively.

Metatarsus primus varus deformity correction is one of the main objectives in hallux valgus surgery. A 'syndesmosis' procedure may be used to correct hallux valgus. An osteotomy is not involved. The aim is to realign the first metatarsal using soft tissues and a cerclage wire around the necks of the first and second metatarsals. We have retrospectively assessed 27 patients (54 feet) using the American Orthopaedic Foot and Ankle Society (AOFAS) score, radiographs and measurements of the plantar pressures after bilateral syndesmosis procedures. There were 26 women. The mean age of the patients was 46 years (18 to 70) and the mean follow-up was 26.4 months (24 to 33.4). Matched-pair comparisons of the AOFAS scores, the radiological parameters and the plantar pressure measurements were conducted pre- and post-operatively, with the mean of the left and right feet. The mean AOFAS score improved from 62.8 to 94.4 points (p < 0.001). Significant differences were found on all radiological parameters (p < 0.001). The mean hallux valgus and first intermetatarsal angles were reduced from 33.2° (24.3° to 49.8°) to 19.1° (10.1° to 45.3°) (p < 0.001) and from 15.0° (10.2° to 18.6°) to 7.2° (4.2° to 11.4°) (p < 0.001) respectively. The mean medial sesamoid position changed from 6.3(4.5 to 7) to 3.6 (2 to 7) (p < 0.001) according to the Hardy's scale (0 to 7). The mean maximum force and the force-time integral under the hallux region were significantly increased by 71.1% (p = 0.001), (20.57 (0.08 to 58.3) to 35.20 (6.63 to 67.48)) and 73.4% (p = 0.014), (4.44 (0.00 to 22.74) to 7.70 (1.28 to 19.23)) respectively. The occurrence of the maximum force under the hallux region was delayed by 11% (p = 0.02), (87.3% stance (36.3% to 100%) to 96.8% stance (93.0% to 100%)). The force data reflected the restoration of the function of the hallux. Three patients suffered a stress fracture of the neck of the second metatarsal. The short-term results of this surgical procedure for the treatment of hallux valgus are satisfactory.

Comparison of plantar pressure distribution patterns between foot orthoses provided by the CAD-CAM and foam impression methods.

Foot orthotic treatment is one of the major conservative methods used to handle foot problems. Total plantar contact foot orthoses are used to reduce and redistribute peak pressures. For the fabrication of a total plantar contact foot orthosis, the computer-aided design and computer-aided manufacturing (CAD-CAM) method has been applied. In this study, the plantar foot-orthosis interface pressure data during walking were collected by the Novel Pedar-mobile in-shoe plantar pressure measuring system. The data were collected under three conditions: (i) Flat insole, (ii) foot orthosis provided by the CAD-CAM method, and (iii) foot orthosis provided by the foam impression method. The Swiss Comfort CAD-CAM foot orthotics system was used in this study. For conditions (ii) and (iii), foot shapes were collected in partial weight bearing and subtalar neutral conditions. Thirty normal subjects were recruited for this study. The plantar foot surface was divided into eight plantar foot regions and then was investigated. These regions included the heel, the medial and lateral arches, the medial, mid and lateral forefoot, the hallux, and the lateral toes. The results showed that the orthoses provided by both the CAD-CAM and foam impression methods could decrease the peak pressure and the maximum force in the heel region, and increase the peak pressure and the maximum force in the medial arch region. Both orthoses redistributed the peak pressure and the maximum force from the heel to the medial arch region. The peak pressure in the mid forefoot region was different between the orthoses provided by the CAD-CAM and foam impression methods.

A longitudinal observational study of preference for elective caesarean section among nulliparous Hong Kong Chinese women.

OBJECTIVE: To establish whether women's preference for elective caesarean section (ELCS) changes as gestation advances. DESIGN: A prospective longitudinal observational study. SETTING: Two units providing obstetric care in Hong Kong, one public and one private. SAMPLE: Five hundred and one nulliparous Chinese pregnant women attending their routine fetal anomaly scan in either unit. METHODS: Consented subjects had two interviews using a structured questionnaire at 18-22 weeks and 35-37 weeks of gestation, respectively. Multivariate analysis was performed to identify determinants for preferring ELCS at the two gestational ages. MAIN OUTCOME MEASURE: The preferences for the mode of delivery at the two gestational ages. RESULTS: The prevalence of maternal preference for ELCS in the study cohort was 17.2% (95% CI 13.9-20.5) and 12.7% (95% CI 9.6-15.8) at mid-trimester and at term, respectively. Significantly more women who preferred ELCS at mid-trimester changed to a trial of vaginal delivery (VD) at term than vice versa (42.0 versus 3.8%). The partner's preference for ELCS was a significant determinant for women preferring ELCS throughout the antenatal period. Among the women booked in the public sector, more women who preferred ELCS at term changed to deliver in private hospitals than those who preferred VD (46.2 versus 9.7%). CONCLUSIONS: Many women changed from preferring ELCS to preferring VD as their pregnancy approached term. The partner's preference was a significant determinant for the women's choice. If a decrease in the proportion of women preferring ELCS is desired, the intervention programme should target the women and their partners who hold such a preference at 20 weeks.

Function and localization of microRNAs in mammalian cells.

microRNAs (miRNAs) represent a large set of master regulators of gene expression. They constitute 1-4% of human genes and probably regulate 30% of protein-encoding genes. These small regulatory RNAs act at a posttranscriptional level-mediating translational repression and/or mRNA degradation-through their association with Argonaute protein and target mRNAs. In this paper, we discuss various mechanisms by which miRNAs regulate posttranscriptionally, including their subcellular localization. Recent results indicate that the majority of miRNA-targeted and thus translationally repressed mRNA is probably distributed in the diffuse cytoplasm, even though a small fraction is concentrated in subcellular compartments, such as processing bodies or stress granules; notably, the stress granule localization of Argonaute depends on the presence of miRNAs. Here we discuss the structural requirement of these subcellular compartments in light of their potential miRNA functions.

A cross-sectional study on the development of foot arch function of 2715 Chinese children.

A cross-sectional study was conducted to investigate the foot arch function of Chinese children. A total of 2715 children, 1246 girls, and 1369 boys, 4-18 years of age were recruited from kindergartens, primary, and secondary schools. The dynamic footprints of the children were collected using a portable pressure-sensing mat. The Contact Force Ratio (CFR, i.e. the ratio of the mid-foot loading to the total loading of the contacted foot, with the toes ignored) of each age group was calculated. In general, the CFR decreased from 4 to 10 years and plateaued at 10-12 years and then increased until 15-16 years. An abnormal low arch foot was defined as the foot that had a CFR value larger than the corresponding age mean plus one standard deviation. The cut-off CFR values of each age group were calculated. With the exception of the 17 years age group, which consisted of a relatively small number of subjects, the percentage of low arch subjects of all the other age groups ranged from 15 to 20%.

Contact force ratio: a new parameter to assess foot arch function.

Static footprint parameters have been used to quantify arch height with conflicting results. This could be caused by the inherent inaccuracy and variations of the methodology used. Since the foot is a dynamic structure that undergoes changes during a step, it is more desirable to capture and analyse the dynamic footprint at an instant during the gait cycle that can most closely reflect the weight-bearing foot function. Forty (40) volunteer subjects were recruited for the reliability test of a new parameter, the Contact Force Ratio (CFR), derived from dynamic footprint. This is a measure of midfoot loading during gait. The mid-gait dynamic footprints were collected using a pressure sensing mat. Results of ICC tests showed that the CFR had good intratester (0.918) and intertester (0.909) reliability. The validity of the method was examined by correlating the parameter to the functional change in arch height, i.e. the Navicular Drop between the non-weight-bearing and weight-bearing conditions.

Enhancement of prosthetics and orthotics learning and teaching through e-Learning technology and methodology.

A Write-Once Publish-Everywhere model was used to create and deliver on-line clinical training and education for undergraduate prosthetics and orthotics students. This project consisted of three phases: developing multimedia learning and teaching tools, integrating these tools into the curriculum (combination of e-Learning and live practical sessions), and evaluating the outcomes. Video-based multimedia contents were captured and integrated with graphic, audio and text into a PowerPoint presentation software format. The web-based content was integrated into the WebCT platform for course management. Questionnaires were used to obtain student feedback on this e-Learning approach. Results were compared within the prosthetics and orthotics (P&O) programme, with other Health Sciences programmes, and overall with the University. P&O student responses were significantly higher than other groups for career relevance and problem solving. Qualitative feedback indicated that students appreciated the easy access, integrated and interactive approach of the text materials, concise PowerPoint presentation, demonstration video and the on-line case discussion via the WebCT platform. Educators appreciated the ability easily to maintain contents and publish the modules across multiple media without recreating the contents.

Orthotic design and foot impression procedures to control foot alignment.

The traditional theory on subtalar joint neutral position and intrinsic foot deformities for the evaluation and treatment of foot and ankle disorders has been the basis for foot orthotics for many years. Although clinical evaluations have suggested a relationship between subtalar pronation and a variety of lower limb problems, such as shin splints and anterior knee pain, recent research has raised serious concerns about the reliability and validity of the assessment and intervention methods. Results of recent studies in foot biomechanics suggest that the orthosis design to control foot alignment should stabilise the medial apical bony structure of the arch to control the first ray mobility and transmit load through the lateral support structures of the foot, locking the calcaneocuboid joint and decreasing strain in the plantar aponeurosis. The concept of "posting" according to a measured foot deformity is de-emphasised. Reliable foot impression procedures are required to provide appropriate orthotic design and thus management. A prone lying position manipulated foot impression method using polycaprolactone based low temperature thermoplastic material was introduced. Ten (10) subjects were recruited to participate in the reliability tests, which were conducted by 2 orthotists specialized in foot orthotics. Results showed high intrarater and interrater reliability of the measured forefoot width and the navicular height. The reliability of the forefoot-rearfoot relationship was demonstrated by the small variance of the root mean square calculation. Subsequently orthotic intervention can be done in a more consistent manner.