Classica Sinica Medica

反折

fǎn zhé

Arched-back reversal · fan zhe

Also rendered: arched-back reversal (Keeps both 反 and 折) · opisthotonos (Technical Greek; names the same thing) · backward bending (Plain description)

Pathology

Reviewed · 2026-09

At a glance

Pinyin
fǎn zhé
Simplified
反折
Literal
反 to turn over, to go back on (《說文》: 覆也); 折 to break, to bend back on itself — the character is an axe cutting grass (《說文》: 斷也). Bent back the wrong way along its own length.
Shuowen
《說文解字》：反，覆也（段注：引申為反覆、違反）；折，斷也（段注：从斤斷艸，引申為折斷、曲折）。

In brief

The second of the three signs at the end of the greater yang, and the one that names a posture: the body folded backward on itself, head and heels drawn together. The chapter gives it two characters, and the tradition reads it as the spine. It is the chapter’s most purely physical sign — nothing in it needs interpreting, you can see it from across the room.

Senses in the classical corpus

1
Bent back on itself 反折
身背反折如弓，即後世所謂角弓反張
太陽之脉，其終也，戴眼、反折 — Suwen 16
2
Second of three signs 戴眼、反折、瘈瘲
目上視、身反折、手足抽掣三者並見
戴眼、反折、瘈瘲 — Suwen 16
3
A posture, not a sensation 反折
不待問而知，望而可見
反折 — Suwen 16

Occurrences in the classics

Passages where the term does real work, with the original, pinyin and English on the same line.

Display
3 passages
素問·診要經終論 Suwen 16 · 診要經終論 Read in context →
歧伯曰：太陽之脉，其終也，戴眼、反折、瘈瘲，其色白，絶汗乃出，出則死矣。 岐伯曰：太阳之脉，其终也，戴眼、反折、瘈瘲，其色白，绝汗乃出，出则死矣。
qí bó yuē: tài yáng zhī mài, qí zhōng yě, dài yǎn, fǎn zhé, chì zòng, qí sè bái, jué hàn nǎi chū, chū zé sǐ yǐ.
Qibo says: When the greater yang channel ends, the eyes are rolled up, the body arches backward, there is twitching and spasm, the colour is white, and the final sweat comes out; once it comes out, death follows.
本篇太陽之終：「戴眼、反折、瘈瘲」。反，說文「覆也」；折，「斷也」。身背反折如弓，後世醫籍謂之角弓反張。本篇以為太陽經氣終絕之候。
素問·刺腰痛 Suwen 41 · 刺腰痛 Read in context →
昌陽之脉，令人腰痛，痛引膺，目䀮䀮然，甚則反折，舌卷不能言，刺内筋爲二痏，在内踝上大筋前，太陰後，上踝二寸所。 昌阳之脉，令人腰痛，痛引膺，目䀮䀮然，甚则反折，舌卷不能言，刺内筋为二痏，在内踝上大筋前，太阴后，上踝二寸所。
Chāng yáng zhī mài, lìng rén yāo tòng, tòng yǐn yīng, mù huāng huāng rán, shèn zé fǎn zhé, shé juǎn bù néng yán, cì nèi jīn wéi èr wěi, zài nèi huái shàng dà jīn qián, tài yīn hòu, shàng huái èr cùn suǒ.
The changyang vessel gives pain in the lower back that draws into the breast; the eyes go dim and blank, and at its worst the body arches backwards and the tongue curls so that the patient cannot speak. Needle the inner sinew twice, in front of the great sinew above the inner ankle and behind greater yin, two inches above the ankle.
**「甚則反折，舌卷不能言」**——**昌陽之脉之極，即太陽之終證**，**與第十六篇「太陽之脉，其終也，戴眼、反折、瘈瘲」同辭**。**本篇「反折」1見**；「反」讀 fǎn、「折」讀 zhé；「舌」讀 shé、「卷」**「舌卷」讀 juǎn**，**與第十六篇厥陰之終「甚則舌卷」同證而異脉**。**本篇「甚則」3見**：**甚則悲以恐、甚則反折、甚則遺溲**——**皆以「甚則」進一層，是本篇條列之定式**。
素問·骨空論 Suwen 60 · 骨空論 Read in context →
督脉爲病，脊強反折。 督脉为病，脊强反折。
Dū mài wéi bìng, jǐ qiáng fǎn zhé.
When the governing vessel is diseased, the spine is stiff and bends backwards.
「督脉爲病，脊「強」讀 qiáng「反」讀 fǎn「折」讀 zhé」——**脊強而身體反折向後，本目所狀正是此形**；**「強」讀 qiáng，本篇1見**；**「折」讀 zhé，本篇3見（反折、連䯒若折、折使榆臂）**；**督脉爲病止此一句，而為後世論督脉者所本**

Compounds built on this term

反
fǎn
to turn over, to go against
說文：覆也
折
zhé
to break, to bend back
說文：斷也
戴眼
dài yǎn
the upturned eyes
本篇與反折並見
角弓反張
jiǎo gōng fǎn zhāng
opisthotonos
後世醫籍之名，即本篇「反折」
太陽
tài yáng
greater yang
本篇「太陽之脉，其終也」

How it has been translated

Every rendering below is a decision about which reader is being addressed. There is no neutral option.

Common Englishopisthotonos, or backward archingThe technical Greek term is standard in clinical writing and is exact.
This sitearched-back reversal反 is to turn over and 折 to break: the body folded the wrong way along its own length. Opisthotonos is shorter and precise, but it is a term of art, and putting a Greek word into this text would be a loss — the chapter is describing, in two characters, exactly what you would see at the bedside. Arched-back reversal keeps the description and keeps 反, which carries the sense of going against the proper direction.

Entry status

Review pending — who reviews this?

2026-09

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Reading path

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