Studies in the Medicine of Ancient India, Part I: Osteology, or the Bones of the Human Body c7.s3.t2.17

c7.s3.t2.17

9. So far as the matter can be traced at present, the first, and really the sole, authority for interpreting *jatru* of the clavicles is the *Amarakoṣa*, an ancient Sanskrit dictionary written by Amara Siṃha, probably in the seventh century A.D. In that work, after explaining the word *aṃsa* to be a synonym of *bhuja-śiras*, or head of the arm, Amara Siṃha proceeds to say (II. 6⁷⁸), *Sandhī tasya eva jatruṇī*, i.e. ‘The two junctions of that (*aṃsa*, or head of the arm) are the two collar-bones.’ Though not very clearly expressed, it is yet clear from the context and the dual number that, in explaining the word *jatru*, he was thinking of the two clavicles. His idea seems to have been that *jatru* was the name of the two bones which run horizontally across the body from one ‘head of the arm’ (or acromion process) to the other, connecting them with each other and with the base of the neck (Fig. 4). How this idea originated is not exactly known; but the following explanation may be suggested. It seems to be a misunderstanding of the two anatomical terms *aṃsa*, collar-bone, and *sandhi*, joint or articulation. The former, as stated already, is interpreted by Amara Siṃha to mean ‘the head of the arm’ (*bhuja-śiras*)¹—a term which evidently is the popular, though inexact, equivalent of the anatomical term *aṃsa-kūṭa*, peak of the shoulder (acromion process, § 55, cl. 5). It is possible that this interpretation was suggested to Amara Siṃha by the peculiar use of the term *aṃsa* in the osteological summary of Vāgbhaṭa I.¹ In that summary, as shown in §§ 39, cl. 4, and 56, cl. 2, *aṃsa* occurs by the side of *akṣaka*, clavicle, and *aṃsa-phalaka*, shoulder-blade, and therefore, if it has any specialized meaning, it can mean only the peak of the shoulder, or the head of the arm. Having once adopted this interpretation, Amara Siṃha was naturally led, by the traditional medical definition of *jatru*, to the further misinterpretation of the latter term. That definition (as reported by Dallana and Aruṇadatta, *ante*, cl. 4) was that *jatru* signified *vakṣo 'ṃsayoḥ sandhi*, that is, the sterno-clavicular articulation. But Amara Siṃha, having taken *aṃsa* to mean the head of the arm, was of necessity driven to interpret the term *sandhi* to signify ‘a connecting bone’, and the definition in question to mean that *jatru* signified the clavicle, because it was the connecting bone (*sandhi*) between the sternum (*vakṣas*) and the head of the arm (*aṃsa*).² But this is not in accordance with anatomical usage: in the latter, *aṃsa* signifies the collar-bone, and *sandhi*, an articulation, that is, the connexion between two contiguous bones. The two terms do not signify, respectively, the summit of the shoulder, and a joint in the sense of a bone that lies between two articulations and connects two other bones. The true anatomical definition of *jatru* is that it is the sterno-clavicular articulation, or, as it is also sometimes, though less technically, expressed, the base of the neck (*grīvā mūla*). Outside the medical schools, the false interpretation of *jatru*, apparently started by the *Amarakoṣa*, that it meant the two clavicles, succeeded in winning general acceptance, so much so that its original and real meaning is, at the present day, practically lost sight of.