Ninomiya Ken 二宮獻 (zì Hikoka / Genka 彥可, 1754–1827, late-Edo / Bunka–Bunsei era), Japanese medical officer of the Hamada han 濱田藩 in Iwami Province 石見國 (modern Shimane Prefecture, on the Sea-of-Japan side of the Chūgoku 中國 region of western Honshū). He travelled west to Nagasaki 長崎 to study under the martial-artist-turned-bone-setter Yoshihara Kyōin 吉原杏隱 (a former bushi, 元武夫, who had developed the jujutsu / kuatsu 死活拳法 (“dead-or-alive boxing-method”) into a system of orthopaedic manipulation). Returning eastward, he combined Yoshihara’s manual-manipulation tradition with the imperial Qīng Zhènggǔ xīnfǎ yàozhǐ of the Yīzōng jīnjiàn and with Dutch rangaku 蘭學 anatomy to produce Seikotsuhan 正骨範 / Zhōngguó jiēgǔ túshuō 中國接骨圖說 (KR3el019, 2 juǎn, Bunka 5 = 1808, published simultaneously in Kyoto, Osaka, and Edo). The work systematises orthopaedic manipulation into 15 “parent-methods” (mǔfǎ 母法), 36 “child-methods” (zǐfǎ 子法), and 150 “kneading-methods” (róufǎ 揉法) named after animal-and-natural-image mnemonics (probing-pearl, leaping-fish, bear-looking-back, phoenix-soaring, crane-straddling, etc.) — a system distinct from and considerably finer-grained than the abstract mōjiēduāntíànmótuīná eight-methods scheme of the Chinese Yīzōng jīnjiàn. It is the first of the “three foundational Japanese orthopaedic treatises” and the principal pre-modern Japanese textbook of bone-setting, ancestral to modern Japanese seikotsu practice.
The work’s title-element Zhōngguó 中國 refers to the Chūgoku region of Japan (the author’s home), not to Imperial China. No CBDB record (a Japanese physician, outside CBDB’s scope).