No abstract

The purpose of this study was to compare the outcome and complications of endoscopic versus open release for the treatment of de Quervain's tenosynovitis. Patients with this condition were randomised to undergo either endoscopic (n = 27) or open release (n = 25). Visual Analogue Scale (VAS) pain and Disabilities of Arm, Shoulder, and Hand (DASH) scores were measured at 12 and 24 weeks after surgery. Scar satisfaction was measured using a VAS scale. The mean pain and DASH scores improved significantly at 12 weeks and 24 weeks (p < 0.001) in both groups. The scores were marginally lower in the endoscopic group compared to the open group at 12 weeks (p = 0.012 and p = 0.002, respectively); however, only the DASH score showed a clinically important difference. There were no differences between the groups at 24 weeks. The mean VAS scar satisfaction score was higher in the endoscopic group at 24 weeks (p < 0.001). Transient superficial radial nerve injury occurred in three patients in the endoscopic group compared with nine in the open release group (p = 0.033). We conclude that endoscopic release for de Quervain's tenosynovitis seems to provide earlier improvement after surgery, with fewer superficial radial nerve complications and greater scar satisfaction, when compared with open release.

Melanogenesis is a well-known physiological response of human skin that may occur because of exposure to ultraviolet light, for genetic reasons, or due to other causes. In our efforts to fi nd new skin lightening agents, palmitoleic acid was investigated for its ability to inhibit melanogenesis. In this study, palmitoleic acid s effect on melanin formation was assessed. Results indicated that palmitoleic acid was shown to down-regulate melanin content in a dose-dependent pattern. To clarify the target of palmitoleic acid action in melanogenesis, we performed Western blotting for tyrosinase, tyrosinase-related protein-1 (TRP-1), TRP-2, and microphthalmia-associated transcription factor (MITF), which are key melanogenic enzymes. Palmitoleic acid inhibited tyrosinase, TRP-2, and MITF expressions in a dose-dependent manner. However, it did not inhibit TRP-1 expression. In order to assess its usefulness in future cosmetic product applications, the cytotoxic effects of the palmitoleic acid were also determined by colourimetric MTT assays using human keratinocyte HaCaT cells. Palmitoleic acid exhibited no cytotoxicity at 500 μM in a human cell line. Therefore, this study suggests that palmitoleic acid is a candidate anti-melanogenic agent, and it might be effective in hyperpigmentation disorders.

Therapeutic study, Level III. See the Guidelines for Authors for a complete description of levels of evidence.