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Background: The role of lateral extra-articular tenodesis (LEAT) to augment primary anterior cruciate ligament reconstruction (ACLR) remains controversial. Purpose: To determine whether the addition of LEAT to primary ACLR provides greater control of rotational laxity and improves clinical outcomes compared with ACLR alone and to assess the impact of early versus delayed ACLR. Study Design: Systematic review; Level of evidence, 3. Methods: Two reviewers independently searched 7 databases for randomized and nonrandomized clinical studies comparing ACLR plus LEAT versus ACLR alone. Animal, cadaveric, and biomechanical studies; revision or repair procedures; and studies using synthetic ligaments and multiligamentous-injured knees were excluded. Risk of bias was assessed with a modified Downs and Black checklist. The primary outcome was postoperative pivot shift. These data were pooled by use of a fixed-effects metaanalysis model. The studies were divided into delayed (>12 months) and early (≤12 months) reconstruction groups for metaanalysis. A best-evidence synthesis was performed on the remaining outcome measures. Results: Of 387 titles identified, 11 articles were included (5 of high quality). Meta-analysis of postoperative pivot shift in 3 studies of delayed primary ACLR showed a statistically significant difference for the pivot-shift test in favor of ACLR with LEAT (odds ratio [OR], 0.44; 95% confidence interval [CI], 0.24-0.81; P =.008; I2 = 0). Meta-analysis of 5 studies of early primary ACLR found no statistically significant difference with the addition of LEAT (OR, 0.60; 95% CI, 0.33-1.09; P =.10; I2 = 33%). Insufficient evidence was available to determine whether the addition of LEAT had any effect on clinical, objective, subjective, and functional outcomes. Conclusion: In primary ACLR, no evidence is available showing additional benefit of LEAT in reducing the postoperative pivot shift in early reconstructions (≤12months); however, LEAT may have a role in delayed ACLR. Strong evidence exists that a combined ACLR and LEAT reduces lateral femoral translation, but there is insufficient evidence to identify any benefit for other clinical outcomes.

Fielding Additively Manufactured (AM) parts requires evaluating both the part���s geometry and material state. This includes geometry that may be optically hidden. Both the geometry and material state affect the vibration response of the parts and modal analysis (identifying natural frequencies) has been shown to be effective for at least simple geometries using ex-situ methods (shaker table and impact hammer excitations). This paper investigates evaluation of the frequency response of metal parts inside the build chamber using the process laser to excite the parts during printing (Renishaw AM250). Vibrations in the part are measured with accelerometers connected to the build plates and used to track the response during printing as during pauses between layers. The laser is modulated at different frequencies and focused onto specific targets to precisely extract the response from individual parts on the build plate. These results are compared to numerical models for metal parts of different geometries and with different material states.

Background: The resurgence in recent attention given to the Anterolateral Ligament has fuelled debate regarding its potential role in knee kinematics, injury, and the need for repair or reconstruction. Surgeons have long recognised that a laterally based extra-articular reconstruction (LEAR) offers a powerful tool to control rotation of the knee. The principle subsequently emerged that combining extra- and intra-articular reconstructions was less likely to fail than either technique performed in isolation. Although successful in reducing anterolateral instability, LEAR fell out of favour when reports emerged about its unpredictability and unsatisfactory results in some cases. Aim: The purpose of this study was to systematically review the current literature on the clinical outcomes following primary anterior cruciate ligament reconstruction (ACLR) with a LEAR. A secondary aim was to compare the clinical outcomes of combined ACLR and LEAR with ACLR alone. Methodology: Systematic Review. Relevant articles were identified by two independent reviewers following a search of seven electronic databases. The inclusion criteria was all published peer-reviewed studies including randomized controlled trials, nonrandomized comparative studies, cohort studies, and case series (> 10 patients) with outcome data following primary ACLR with a LEAR with more than two years follow-up. The exclusion criteria included extra-articular procedures performed in isolation, synthetic ACLR or LEAR, cases with greater than two surgically treated knee ligaments or combined alignment knee surgery, ACL repair, reports on guidelines, technical notes, reviews or systematic reviews. Methodological quality assessment was performed using the MINORS criteria. Data was obtained using a data-extraction form developed specifically for this review. The outcomes of interest included postoperative clinical examination, objective, subjective, functional and radiographic evaluation. A meta-analysis was performed using a random effects model on available data. Results: The literature search yielded 363 articles. After titles and abstracts were reviewed, 125 articles were selected for full-text review, of which 32 studies met the inclusion criteria (11 comparative studies 21 non-comparative studies). Of the 11 comparative studies, 5 recommended a combined LEAR and ACLR, 5 were in favour of the ACLR alone, and 1 was equivocal. Meta-analysis demonstrated a statistically significant difference for the pivot-shift test in favour of a combined LEAR and ACLR. All but 2 of the non-comparative groups reported a satisfactory outcome with combined ACLR and LEAR at a minimum of two years. Three long-term studies (>10 years) found there was no increased rate of lateral compartment osteoarthrosis with LEAR. Conclusions: A meta-analysis of data acquired from studies comparing ACLR to a combined ACLR with a LEAR, revealed a significantly reduced the post-operative pivot shift with LEAR. Review of the recommendations of 11 comparatives studies reached an equivocal verdict as to effectiveness of a LEAR in conjunction with ACLR. A number of studies advocated that a LEAR was not necessary when treating an acutely rupture ACLR in the primary setting, however, in the chronic setting it may have greater utility. Based on the available radiographic data, long term follow-up of ACLR with LEAR, there was no evidence of an increased incidence of lateral compartment osteoarthrosis.

Fragestellung: Der Prozess der Frakturheilung führt zur narbenfreien Heilung und Wiederherstellung der ursprünglichen Struktur und Funktion. Neuere Studien lassen einen entscheidenden Einfluss der T-Zellen des adaptativen Immunsystems auf das Ergebnis der Knochenheilung vermuten. In dieser[for full text, please go to the a.m. URL], Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2013)

Permanent Nd-Fe-B sintered magnets were fabricated with the metal injection molding technique. The alloy powder was mixed with a multi-component binder system, generating a feedstock that was injection molded into cube-shaped samples, under magnetic field for crystallographic texture development. Subsequently, samples underwent binder extraction in two stages (chemical and thermal) and were sintered under high vacuum. This study is focused on the effect of process variables on the magnet's texture. The texture degree, expressed by the alignment factor f(phi), was evaluated by analyzing the second quadrant of hysteresis curve. As expected, results show that magnetic field intensity during injection molding plays an important role on particle alignment, but acts in combination with particle mobility, which in turn, is dictated by the other process variables. For example, by increasing feedstock's viscosity and powder loading, the alignment factor, and consequently the remanence, decreases. In optimized conditions it is possible to obtain an alignment factor of 95%, above uniaxially pressed, sintered Nd-Fe-B magnets, resulting in elevated flux density magnets.