Treatment of midshaft clavicular delayed and non-unions with anteroinferior locking compression plating

INTRODUCTION: Pain and impaired shoulder function are the predominant symptoms of midshaft clavicle non-unions. Obtaining consolidation and improvement of shoulder function is often successfully achieved with osteosynthesis and bone grafting. Most data in the literature pertain to plate osteosynthesis, placing the plate on the subcutaneous superior aspect of the clavicle. Although union rates are generally high, most patients require hardware removal as the plate is prominent under the skin causing pain and cosmetic problems. MATERIALS AND METHODS: In the current retrospective study, we followed a cohort of 21 consecutive cases (20 patients) with a midshaft clavicular delayed or non-union, treated with anteroinferior plating using a 3.5 mm locking compression plate (LCP) for a mean of 30 months. RESULTS: We operated on 10 males and 10 females with a mean age of 48.2 years (range 16-65). There was one early plate failure that needed revision. Two patients required hardware removal because of prominence of the plate. All but two patients were satisfied with the final cosmetic result. The average DASH score at follow up was 22.8. DISCUSSION AND CONCLUSIONS: Anteroinferior plating with a 3.5 mm LCP is a reliable and reproducible treatment of midshaft clavicular delayed and non-union regarding consolidation, function, cosmesis and reduction of second surger

Density Functional Study of Ground and Excited States of MnC2(CO)C10

The precise nature of the excited states of Mn2(CO)lo leading to the well-known photochemistry-both Mn-Mn and Mn-CO bond breaking upon low-energy excitation-is still unclear. In order to identify possibly dissociative excited states (either Mn-Mn, Mn-CO,, or Mn-CO,,), the nature of the highest occupied Mn-3d orbitals is analyzed as well as the composition of the virtual orbitals. The following features are noted. (a) The low-energy excitations at 337-355 nm arise from B - CJ* and dn - u* excitations, while d - d excitations occur at much higher energy. (b) The Mn-Mn CJ bonding HOMO as well as the u* LUMO cannot simply be classified as arising from the 3d,2 components of eg parentage in the local octahedrons around Mn, they have little 3d,2 - 3d,2 (anti)bonding character but significant contributions come from M n - 4 ~ a~n d CO-2ne,, orbitals. Mn-Mn B antibonding is only strong in the B* orbital due to these contributions. (c) Due to the strong involvement of Mn-4p2, th 3d,2 orbital not only occurs in the B and u* orbitals but also in a higher set of virtuals, denoted d,d*, -1.5 eV above the u* orbital. Antibonding with axial CO’s is strong in these higher virtuals but absent or weak in the B and CJ* orbitals. CJ antibonding with equatorial CO’s is strong in the 3d2+ orbital of eg parentage, that is located very high in the virtual spectrum, -2 eV above the u* orbital. Mn-Mn dissociation will occur only from the B - B* excitation; CO loss will probably occur from the high-lying d - d excited states (excitations into d,d* and 3d2-,2). The observed photochemistry at low energy will have to be explained from curve crossings between the low-energy excited states and the photoactive states

Measuring hindfoot alignment radiographically: the long axial view is more reliable than the hindfoot alignment view

BACKGROUND: Hindfoot malalignment is a recognized cause of foot and ankle disability. For preoperative planning and clinical follow-up, reliable radiographic assessment of hindfoot alignment is important. The long axial radiographic view and the hindfoot alignment view are commonly used for this purpose. However, their comparative reliabilities are unknown. As hindfoot varus or valgus malalignment is most pronounced during mid-stance of gait, a unilateral weight-bearing stance, in comparison with a bilateral stance, could increase measurement reliability. The purpose of this study was to compare the intra- and interobserver reliability of hindfoot alignment measurements of both radiographic views in bilateral and unilateral stance. MATERIALS AND METHODS: A hindfoot alignment view and a long axial view were acquired from 18 healthy volunteers in bilateral and unilateral weight-bearing stances. Hindfoot alignment was defined as the angular deviation between the tibial anatomical axis and the calcaneus longitudinal axis from the radiographs. Repeat measurements of hindfoot alignment were performed by nine orthopaedic examiners. RESULTS: Measurements from the hindfoot alignment view gave intra- and interclass correlation coefficients (CCs) of 0.72 and 0.58, respectively, for bilateral stance and 0.91 and 0.49, respectively, for unilateral stance. The long axial view showed, respectively, intra- and interclass CCs of 0.93 and 0.79 for bilateral stance and 0.91 and 0.58 for unilateral stance. CONCLUSION: The long axial view is more reliable than the hindfoot alignment view or the angular measurement of hindfoot alignment. Although intra-observer reliability is good/excellent for both methods, only the long axial view leads to good interobserver reliability. A unilateral weight-bearing stance does not lead to greater reliability of measuremen