48. But of what import to us are the means which nature employs? The indication is still the same. The fragments must be always kept in contact, that the reunion may be immediate, and that, as David observes, in his memoir on motion and rest in surgical diseases, the apophysis may not, by becoming too long in consequence of the space occupied by the callus, impede the extension of the forearm on the os humeri. § XVI. OF THE MEANS OF CONTACT BETWEEN THE FRAGMENTS. 49. There are no fractures, the treatment of which demands more attention, or is surrounded with more difficulties, than that of the olecranon. Here art cannot, as in the thigh, and the clavicle, oppose to the ever active power of the natural muscles, a constant resistance produced by the action of a kind of artificial muscle, consisting in permanent extension. The superior fragment, being too small to give any purchase to extending forces, can be only pushed downwards, and kept in that position with a greater or less degree of stability and firmness, while the ulna, so to speak, is drawn to meet it. Whence it follows, that extension here is of little use, and that it is chiefly by position or attitude, aided by a judicious conformation, that the reduction is effected. 50. The position has varied in the hands of different practitioners. Some have proposed that, in which the fore-arm is half-bent, so as to form a right angle with the os humeri. The example mentioned by David, is not the only one where recourse has been had to this. But, by rejecting the general principle respecting the reunion of parts, which requires them to be kept in perfect contact, this mode is exposed to a double inconvenience. The reunion is extremely slow in being accomplished, and, when ultimately obtained, is accompanied by the loss of one part of the movements of the limb, in consequence of the length of the callus. This callus must necessarily fill up the whole space that intervened between the fragments during the treatment, and being thus added to the natural extent of the olecranon, lengthens this appendix to such a degree, that, in extending the fore-arm, its summit or upper end comes too soon into contact with the cavity in the os humeri destined to receive it. 51. This practice appears to have been chiefly owing to an opinion then in existence, that an anchylosis being the necessary consequence of the fracture, it was proper to place the arm in that position in which it would be most likely to be still of some service.