Extension-elicited blanching of the dorsal phalanges in systemic sclerosis - Video Data

Systemic sclerosis (SSc) is a multisystem disease that normally first manifests in the skin. To help differentiate early pathogenic phalangeal edema that often precedes finger skin thickening from normal variants, we report the clinical sign of extension-elicited blanching of the dorsal phalanges associated with SSc. We often observe this blanching phenomenon of the dorsal phalanges in our patients with early-stage disease (Video 1). However, attention to this clinical sign has been underreported and provides an additional clue toward diagnosing SSc.
To appreciate pathogenic phalangeal blanching associated with SSc, patients make a fist with their hands and hold it. Upon releasing the fist and fully extending the phalanges, blanching of the dorsal aspects of their fingers can be elicited. The blanching ranges from the metacarpophalangeal joints over the proximal phalanges and proximal interphalangeal joints to the middle phalanges. It can be present symmetrically in all five fingers but is often less prominent on the thumbs.

系统性硬化症（Systemic sclerosis, SSc）是一种多系统疾病，通常首发于皮肤。为协助鉴别常先于手指皮肤增厚出现的病理性指骨水肿与正常变异，本文报道了一种与SSc相关的伸指诱发指骨背面苍白征。我们在早期SSc患者中常观察到此指骨背面苍白现象（视频1）。但目前对该临床体征的关注仍不足，而该体征可为SSc的诊断提供额外线索。

要观察到与SSc相关的病理性指骨苍白，需让患者双手握拳并保持片刻。松开拳头并完全伸展指骨时，即可诱发手指背面苍白。该苍白区域可覆盖掌指关节、近节指骨及近端指间关节至中节指骨。双侧五指均可出现该表现，但拇指的苍白程度通常较轻。