Does Bowstringing Affect Hand Function in Patients Treated With A1 Pulley Release for Trigger Fingers?: Comparison Between Percutaneous Versus Open Technique.

We aimed to inspect bowstringing after percutaneous and open release of the A1 pulley for trigger digits and its influence on hand function. Sixty-two patients with a resistant trigger digit were randomized to undergo either open release or percutaneous release of the A1 pulley. We quantified bowstringing of the digit using ultrasonography preoperatively and at 12 and 24 weeks after surgery. Pain on a visual analog scale; Disabilities of the Arm, Shoulder, and Hand questionnaire; pinch power; and grip strength were assessed. Bowstringing was significantly increased at 12 weeks after surgery in both groups, and the mean value of the open release group was significantly greater than that of the percutaneous group (2.30 ± 0.58 mm vs 1.46 ± 0.51 mm, respectively; P = 0.035). However, the bowstringing was decreased at 24 weeks without showing significant difference between the 2 groups. The clinical outcomes of each cohort improved significantly, with no difference between the groups at final follow-up. No association was found between bowstringing and any clinical outcome measure. Bowstringing occurred by A1 pulley release with either the percutaneous or open technique does not affect clinical hand function in patients with trigger fingers.

Topographical Anatomy of the Distal Ulna Attachment of the Radioulnar Ligament.

PURPOSE: The deep component of the distal radioulnar ligament provides translational stability and rotational guidance to the forearm. However, controversy exists regarding the importance of this structure as well as the nature of its attachment to the distal ulna. We aimed to evaluate the topographic anatomy of the distal ulna attachment of both the superficial and the deep components of the radioulnar ligament and to assess the relationship between its internal and its external morphometry. METHODS: Thirteen human distal ulnae attached by ulnar part of the distal radioulnar ligament were scanned using micro-computed tomography and reconstructed in 3 dimensions. In addition, the distal radioulnar ligaments were examined under polarized light microscopy to determine the histological characteristics of collagen contained within the ligaments. RESULTS: The deep limbs have broad marginal insertions at the fovea, whereas the superficial limbs have a circular and condensed insertion to the ulnar styloid. The center of the deep limb was separated from the base of the ulnar styloid by a mean of 2.0 ± 0.76 mm, and this distance was positively correlated with the width of the ulnar styloid. The mean distance between the center of the ulnar head and the center of the fovea was 2.4 ± 0.58 mm. The proportion of collagen type I was lower in the deep limb than in the superficial limb. CONCLUSIONS: This new observation of the footprint of the radioulnar ligament in the distal ulna indicates that the deep limb may serve as an internal capsular ligament of the distal radioulnar joint, whereas the superficial limb as the external ligament. CLINICAL RELEVANCE: Knowledge of the topographic anatomy of the radioulnar ligament's attachment to the distal ulna may provide a better understanding of distal radioulnar ligament-related pathologies.

Sonographic Quantification of Pronator Quadratus Activity During Gripping Effort.

OBJECTIVES: The aim of this study was to obtain quantitative data related to the activity of each head of the pronator quadratus based on dynamic sonographic parameters during gripping effort and to assess their relationships with grip and pronation strengths. METHODS: The forearms of 33 healthy volunteers were evaluated at 5 positions of axial rotation (full supination, 45° supination, neutral, 45° pronation, and full pronation). Echogenic intensity ratios and muscle thicknesses of each head of the pronator quadratus were measured from transverse cross-sectional sonograms obtained during maximal grip and release. Grip strengths and maximal isokinetic pronation torques at 90°/s and 360°/s were evaluated as strength parameters and correlated with sonographic measures. RESULTS: Echogenic intensity ratios of both heads significantly decreased during power grip (P ≤ .002). Changes in echogenic intensity ratios of the superficial head were greater when the forearm was pronated compared to supination (P < .001), whereas changes in echogenic intensity ratios of the deep head were constant at all forearm positions. Muscle thicknesses of the superficial head maximally increased at the neutral position during power grip (P < .001), whereas muscle thicknesses of the deep head did not change. There were significant negative correlations between grip strength and echogenic intensity ratios of both heads at all respective forearm positions (P ≤ .048). Pronation torque was significantly correlated with echogenic intensity ratios of the superficial head at all forearm positions and the deep head at 45° and full pronation positions (P ≤ .034). CONCLUSIONS: The data revealed that the superficial head of the pronator quadratus more actively contracts when the forearm is in pronation, whereas the deep head constantly contracts at all positions. This study suggests that both heads of the pronator quadratus also play a role in grip strength, but the superficial head contributes more to pronation strength.

Restoration of the central slip in congenital form of boutonniere deformity: case report.

We present a case of a congenital form of a boutonniere deformity involving both little fingers with a poorly differentiated extensor mechanism and the absence of the tendinous attachment on the dorsal aspect of the middle phalanx. This complex deformity was evaluated histologically followed by successful reconstruction of the central slip.

CdS/C60 binary nanocomposite films prepared via phase transition of PS-b-P2VP block copolymer.

We demonstrate the well-defined control of phase transition of a polystyrene-b-poly(2-vinylpyridine) (PS-b-P2VP) block copolymer from spherical micelles to lamellar structures, in which CdS and C60 nanoparticles (NPs) are selectively positioned at the P2VP domains. The CdS NPs are in situ synthesized using PS-b-P2VP block copolymer templates that are self-assembled in PS-selective solvents. The CdS-PS-b-P2VP micellar structures are transformed to lamellar phase by adjusting a solvent selectivity for both blocks. In addition, a binary system of CdS/C60 embedded in PS-b-P2VP lamellar structures (CdS/C60-PS-b-P2VP) is fabricated by embedding C60 molecules into P2VP domain though charge-transfer complexation between pyridine units of PS-b-P2VP and C60 molecules. The CdS/C60-PS-b-P2VP nanostructured films are characterized by transmission electron microscopy (TEM) and UV-Vis spectrometer.

Au-coated 3-D nanoporous titania layer prepared using polystyrene-b-poly(2-vinylpyridine) block copolymer nanoparticles.

New nanoporous structures of Au-coated titania layers were prepared by using amphiphilic block copolymer nanoparticles as a template. A 3-D template composed of self-assembled quaternized polystyrene-b-poly(2-vinylpyridine) (Q-PS-b-P2VP) block copolymer nanoparticles below 100 nm was prepared. The core-shell-type nanoparticles were well ordered three-dimensionally using the vertical immersion method on the substrate. The polar solvents were added to the polymer solution to prevent particle merging at 40 degrees C when considering the interaction between polymer nanoparticles and solvents. Furthermore, Au-coated PS-b-P2VP nanoparticles were prepared using thiol-capped Au nanoparticles (3 nm). The 3-D arrays with Au-coated PS-b-P2VP nanoparticles as a template contributed to the preparation of the nanoporous Au-coated titania layer. Therefore, the nanoporous Au-coated titania layer was fabricated by removing PS-b-P2VP block copolymer nanoparticles by oxygen plasma etching.