Isolated scaphotrapeziotrapezoid osteoarthritis is rare but can cause weakness and wrist pain. We present the results of a pilot study of interposition arthoplasty with a scaphoid trapezium ...pyrocarbon implant (STPI) by an open and arthroscopic approach for this problem. We performed this procedure in 10 hands in eight patients, all women, with a mean age of 60.5 (range 51–70) years. The average follow-up was 19 (range 2–24) months. Pre-operative X-rays in all cases identified an isolated degenerative arthritis of the scaphotrapeziotrapezoid joint. Average DASH evaluation pre-operatively of 49 was reduced to 39. All of the patients had functional improvement and returned to daily activities after 3 months. The results of this pilot study suggest that the STPI may prove a useful compromise treatment for this problem.
Dans de rares circonstances d’aplasie ou d’hypoplasie du pouce, la pollicisation de l’index est déconseillée ou simplement impossible. Cela est le cas si les doigts pollicisables sont hypoplasiques ...ou malformés ou lorsqu’une pince ulnaire s’est déjà développée spontanément. Fonctionnellement logique dans ces cas, la pollicisation du cinquième doigt en position ulnaire donne un aspect grotesque inacceptable à la main. Afin de bénéficier des aspects fonctionnels de cette pollicisation ulnaire tout en préservant une esthétique correcte nous décrivons la pseudo-pollicisation par ostéotomie de supination ulnaire (POSU). Cette intervention combine la création d’une large commissure entre les deux doigts les plus ulnaires à une rotation du cinquième rayon pour améliorer la pince pulpaire ulnaire et permettre une prise large par hyper-extension de l’articulation métacarpophalangienne du cinquième doigt. Nous avons utilisé cette intervention dans cinq cas revus avec un recul minimum d’un an et demi.
In certain rare cases of thumb aplasia or hypoplasia, pollicisation of the second finger is not recommended or impossible. It happens when the most radial fingers are hypoplastic or abnormal or when an ulnar prehension pattern has already developed. In these cases, if functional, pollicisation of the most ulnar finger in not suitable because of the ugly cosmetic result. In order to combine the functional advantages of the ulnar pollicisation with a satisfactory cosmetic appearance, the authors describe pseudo-ulnar pollicisation by supination osteotomy. This operation combines rotation of the fifth ray with the establishment of a larger web space between the two most ulnar fingers. We have used this technique in five preliminary cases with a minimum follow-up of 18 months.
Nous présentons ici le cas d’un jeune homme de 22 ans, vu en consultation pour une instabilité statique du poignet droit suite à un accident de la voie publique survenu six mois auparavant. Le ...traitement de cette instabilité consistait en un transfert musculaire actif du tendon du muscle court extenseur radial du carpe. Le tendon sectionné à son insertion sur la base du troisième métacarpien, a été réinséré dans la partie distale du scaphoïde à l’aide de deux ancres de Mitek après raccourcissement d'un centimètre. Le tendon passait autour d’une poulie créée au niveau du tubercule dorsal du radius afin de le placer sur l’axe du scaphoïde. Aucun autre matériel de synthèse n’a été utilisé et le poignet a été immobilisé en extension pendant une période de six semaines. Le contrôle clinique et radiologique à huit mois de l’intervention a confirmé une excellente réduction de l’instabilité avec un poignet doté d’une mobilité satisfaisante et indolore.
We present the case of a twenty year old man who developed static scapholunate instability on the right side following a road traffic accident seven months previously. A dynamic surgical technique was devised to treat this problem using the tendon of extensor brevi carpi radialis as an active transfer. The tendon, divided at its insertion on the base of the third metacarpal, was reinserted into the distal part of the scaphoid using two anchors after shortening it by removing the distal centimetre. The tendon was rerouted via a pulley created ‘de novo’ at Lister’s tubercle in order to centre the tendon on the same axis as the scaphoid. No other material was used for bone fixation. The wrist was immobilized in extension for six weeks. The clinical and radiological result eight months after the intervention showed excellent reduction of the scapholunate joint and a pain-free wrist with satisfactory mobility.
We present the analysis of Fermi Large Area Telescope (LAT) {\gamma}-ray observations of HB 21, a mixed-morphology supernova remnant. Such supernova remnants are characterized by an interior thermal ...X-ray plasma, surrounded by a wider nonthermal shell emitting at radio frequencies. HB 21 has a large angular size, making it a good candidate for detailed morphological and spectral studies with the LAT. The radio extension is 2{\deg}x1{\deg}.5, compared to the LAT 68% containment angle of ~1{\deg} at 1 GeV. To understand the origin of {\gamma}-ray emission, we compare LAT observations with other wavelengths that trace non-thermal radio synchrotron, nearby molecular clouds, shocked molecular clumps, and the central X-ray plasma. Finally, we model possible hadronic and leptonic emission mechanisms. We conclude that {\gamma}-rays from HB 21 are likely the result of electron bremsstrahlung or proton-proton collisions with dense material due to interaction with the nearby clouds.
The flat-spectrum radio quasar PKS 1441+25 at a redshift of z = 0.940 is detected between 40 and 250 GeV with a significance of 25.5 {\sigma} using the MAGIC telescopes. Together with the ...gravitationally lensed blazar QSO B0218+357 (z = 0.944), PKS 1441+25 is the most distant very high energy (VHE) blazar detected to date. The observations were triggered by an outburst in 2015 April seen at GeV energies with the Large Area Telescope on board Fermi. Multi-wavelength observations suggest a subdivision of the high state into two distinct flux states. In the band covered by MAGIC, the variability time scale is estimated to be 6.4 +/- 1.9 days. Modeling the broadband spectral energy distribution with an external Compton model, the location of the emitting region is understood as originating in the jet outside the broad line region (BLR) during the period of high activity, while being partially within the BLR during the period of low (typical) activity. The observed VHE spectrum during the highest activity is used to probe the extragalactic background light at an unprecedented distance scale for ground-based gamma-ray astronomy.
We report the Fermi Large Area Telescope (LAT) detections of high-energy (>100 MeV) gamma-ray emission from two recent optically bright classical novae, V1369 Centauri 2013 and V5668 Sagittarii 2015. ...At early times, Fermi target-of-opportunity observations prompted by their optical discoveries provided enhanced LAT exposure that enabled the detections of gamma-ray onsets beginning ~2 days after their first optical peaks. Significant gamma-ray emission was found extending to 39-55 days after their initial LAT detections, with systematically fainter and longer duration emission compared to previous gamma-ray detected classical novae. These novae were distinguished by multiple bright optical peaks that encompassed the timespans of the observed gamma rays. The gamma-ray light curves and spectra of the two novae are presented along with representative hadronic and leptonic models, and comparisons to other novae detected by the LAT are discussed.
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