Arthroscopic Oblique Partial Ulnar Styloid Resection for Ulnar Styloid Impaction Syndrome

Background Open or arthroscopic partial resection of the elongated ulnar styloid is the surgical treatment of choice for ulnar styloid impaction syndrome. Case Description A patient with a severely elongated processus styloideus ulnae (PSU) with a chronic impaction of the distal-radial margin against the triquetrum suffered a traumatic triangular fibrocartilage complex (TFCC) Palmer 1B rupture and DRUJ instability. The length of the PSU was 9 mm. After failed conservative treatment, a partial oblique arthroscopic resection of the PSU and simultaneous TFCC reinsertion were performed with uneventful recovery. Literature Review Arthroscopic resection has emerged as an alternative to the traditional open PSU resection for the treatment of styloid impaction syndrome. A transverse resection is described as the treatment of choice. Regarding the extent of resection subtotal ligament sparing resection or resection to the lower margin have been suggested. Clinical Relevance Surgical planning of PSU resection should take into consideration the anatomy of the impingement. The extent of resection should be planned individually, and sometimes an oblique resection may be the preferred option.

Anatomische Landmarken für periphere Nervenblöcke an Unterarm und Handgelenk: Eine Untersuchung an Leichenpräparaten

Zusammenfassung Hintergrund Es gibt keine Daten, die eine standardisierte, auf Orientierungspunkten basierende Technik zur Blockierung sensibler Nerven des Unterarms gewährleisten. Ziel Ziel dieser Untersuchung war es, Stellen an Unterarm und Ellenbogen zu definieren, an denen unter Orientierung an gut tastbaren knöchernen Landmarken Nervenblockaden relativ sicher erfolgreich möglich sind. Methoden An fünf Leichenarmen wurden der Ramus superficialis des N. radialis (RSNR), der dorsale Ast des N. ulnaris (RDNU), der laterale, mediale und dorsale N. cutaneus antebrachii (NCAL, NCAM, NCAD) sowie der Ramus palmaris des N. medianus (RPNM) präpariert. In Bezug auf den Processus styloideus radii und ulnaris, das Listerʼsche Tuberkulum sowie den Epikondylus medialis und lateralis sowie Verbindungslinien zwischen diesen gut tastbaren Knochenvorsprüngen wurden Stellen lokalisiert, an denen die vorgenannten Nerven aufzufinden und zu blockieren sind. Ergebnisse Die Nerven können an folgenden Stellen sicher blockiert werden: der RSNR 85 mm proximal des Listerʼschen Tuberkels auf einer Linie zwischen letzterem und dem Epicondylus humeri medialis; der NCAL 38 mm und der NCAD 32 mm ulnar vom Epicondylus humeri lateralis; der NCAM 14 mm radial zum medialen Epicondylus; der RDNU 27 mm proximal zum Ulnastyloid in Richtung des lateralen Epicondylus; der RPNM auf einer nach ulnar zielenden Senkrechten zur Verbindungslinie zwischen dem Processus styloideus radii (PSR) und dem medialen Epikondylus 45 mm proximal des PSR und 21 mm nach ulnar. Schlussfolgerung Unter Verwendung gut tastbarer Knochenvorsprünge am distalen Unterarm und Ellenbogen und Verbindungslinien zwischen ihnen lassen sich der RSNR, RDNU, RPNM sowie die NNCAL/M und D sicher lokalisieren. Evidenzgrad IV

Dominance of the Right Hemisphere and Role of Area 2 in Human Kinesthesia

We have previously shown that motor areas are engaged when subjects experience illusory limb movements elicited by tendon vibration. However, traditionally cytoarchitectonic area 2 is held responsible for kinesthesia. Here we use functional magnetic resonance imaging and cytoarchitectural mapping to examine whether area 2 is engaged in kinesthesia, whether it is engaged bilaterally because area 2 in non-human primates has strong callosal connections, which other areas are active members of the network for kinesthesia, and if there is a dominance for the right hemisphere in kinesthesia as has been suggested. Ten right-handed blindfolded healthy subjects participated. The tendon of the extensor carpi ulnaris muscles of the right or left hand was vibrated at 80 Hz, which elicited illusory palmar flexion in an immobile hand (illusion). As control we applied identical stimuli to the skin over the processus styloideus ulnae, which did not elicit any illusions (vibration). We found robust activations in cortical motor areas [areas 4a, 4p, 6; dorsal premotor cortex (PMD) and bilateral supplementary motor area (SMA)] and ipsilateral cerebellum during kinesthetic illusions (illusion-vibration). The illusions also activated contralateral area 2 and right area 2 was active in common irrespective of illusions of right or left hand. Right areas 44, 45, anterior part of intraparietal region (IP1) and caudo-lateral part of parietal opercular region (OP1), cortex rostral to PMD, anterior insula and superior temporal gyrus were also activated in common during illusions of right or left hand. These right-sided areas were significantly more activated than the corresponding areas in the left hemisphere. The present data, together with our previous results, suggest that human kinesthesia is associated with a network of active brain areas that consists of motor areas, cerebellum, and the right fronto-parietal areas including high-order somatosensory areas. Furthermore, our results provide evidence for a right hemisphere dominance for perception of limb movement.