Replicated evolutionary patterns are often attributed to recurrent emergence following parallel selective pressures. However, similar genetic patterns (e.g., 'genomic islands') can also emerge following extensive homogenization in secondary contact, as a by-product of heterogeneous introgression. For example, within Himalayan tributaries of the Ganges/Brahmaputra rivers, drainage-specific mtDNA clades of polyploid snowtrout (Cyprinidae: Schizothorax) are partitioned as co-occurring morphological 'ecotypes,' hypothesized to represent parallel divergence among adjacent streams. To evaluate this scenario, we utilized a reduced-representation genomic approach (N=35,319 de-novo and N=10,884 transcriptome-aligned SNPs) applied to high-altitude Nepali/Bhutanese snowtrout (N=48 each). We unambiguously quantified ploidy levels by first deriving genome-wide allelic depths followed by ploidy-aware Bayesian models that produced genotypes statistically consistent with diploid/tetraploid expectations. When genotyped SNPs were clustering within drainages, the convergence of eco-phenotypes was sustained. However, subsequent partitioned analyses of phylogeny and population admixture instead identified subsets of loci under selection which retained genealogical concordance with morphology, with apparent patterns of parallel ecotype emergence instead driven by widespread genomic homogenization. Here, prior isolation is effectively masked by admixture occurring in secondary contact. We note two salient factors:1) Polyploidy has promoted homogenization in tetraploid Himalayan snowtrout; and 2) Homogenization varies across Himalayan tributaries, presumably in lockstep with extent of anthropogenic modification.

Traumatic Extensor Carpi Ulnaris (ECU) sublaxation is often missed and undiagnosed or wrongly diagnosed. ECU muscle plays a key role in active movement of wrist extension, ulnar deviation and also in providing suport to the ulnar side of wrist. Its position relative to the other structures in the wrist changes with forearm pronation and supination. As such it must be mobile yet stable. This structure can be injured in a variety of different athletic activity and following fall on outstretched hand. It lies subcutaneously and easily palpated and visualized, allowing early diagnosis and management. We in our study report a case of traumatic ECU sublaxation. An 18 year old female patient presented to our OPD with ulnar side wrist pain. MRI showed volar subluxed ECU tendon with ruptured ECU sheath. We had done open ECU sheath repair and excision of bursa. Very few literature shows traumatic ECU sublaxation report. The case is reported for the rarity of presentation and likely to misdiagnose in day to day clinical scenario.

No abstract

Background: Pedicle screw fixation of lower cervical spine is a new technique that provides an alternative to posterior lateral mass plating. Although biomechanical studies suggest the use of pedicle screws to reconstruct the cervical spine, placing screw in small cervical pedicle poses a technical challenge. Penetreation of screw in pedicle is a primary complication associated with screw insertion in the lower cervical spine. Aim and Objective: To manage the cervical spine injuries by pedicle screw presented to department of Orthopaedics, BPKIHS, Dharan. Materials and methods: This is retrospective interventional study done at the department of Orthopaedics, B.P. Koirala Institute of Health Sciences, Dharan, Nepal over a period of 2 years from March 2012 to April 20014. A total of 55 patients with cervical spine injuries were treated by pedicle screw. The patient's age ranged from 20 to 60 years and the mean follow-up was 12 weeks. Results: The study comprised of 55 patients with cervical spine injuries were treated by pedicle screw The age incidence in this series ranged from 20 years to 60 years. 40 patients were males and 20 was female. All had fractures or fracture dislocation at different levels of lower cervical spine. The mechanism of injury included falls from height (80%), motor vehicle accidents (18%) and sports related injury (2%). Discussion: Pedicle screw insertion into the pedicles in the lower cervical spine is technique that requires a solid knowledge of 3-dimensional anatomy of cervical spine and experience of pedicle screw fixation in thoracolumbar spine. The biomechanical advantages of pedicle screw fixation in cervical spine is obvious, but data are limited. However, safety and role of pedicle screw fixation in reconstruction in the lower cervical spine have not been defined. Conclusion: It is indicated in patients with osteoporotic bone or when rigid internal fixation can not be achieved by conventional techniques.