(31a) The Fracture Shown in Plate XII., six months after reception of the injury

The amount of callus furnished around the loose fragments is very striking.

The upper end of the bone is shown to have been divided into at least two fragments, hence one of the difficulties of maintaining the ends in apposition. The stoppage of the fissuring short of the epiphysis is characteristic.

Slighter injuries to the femur in which the shaft was chipped or grooved without loss of continuity were not uncommon, and showed well the capacity of the bone to withstand the lateral shock transmitted by small bullets. Two figures inserted in the chapter on wounds in general (figs. 22, 23, pp. 61, 62) are of cases in which, from the appearance of the wound of exit, the bullet probably underwent deformation, or was so deflected as to escape on a considerably altered axis. Beyond the nature of the exit wound in the case depicted in fig. 22, some thickening beneath the femoral vessels denoted bone injury, but unfortunately no skiagram was taken.

I saw no case in which a transverse fracture of the shaft accompanied such injuries, but am under the impression that, if they had been produced by bullets of greater volume and weight, transverse solution of continuity would have been more common. In point of fact, no case of pure transverse fracture of the femur ever came under my notice.

The diagram depicted in fig. 51, p. 164, is from a sketch made of the lower end of a femur in which a severely comminuted fracture followed by suppuration necessitated an amputation of the thigh, performed by Major Lougheed, R.A.M.C. It is inserted as an illustration of the tendency of the fissures to stop short above the actual articular extremities of the bones. In this case the comminution was extreme and accompanied by the usual long lateral fragments, one of which measured five inches in length and might well have extended into the knee-joint had that been an ordinary occurrence.

Perforations of the lower extremity of the bone were very common. These were sometimes transverse and limited to the articular extremity itself, or the same limitation occurred to the antero-posterior tracks. These were the slightest forms of injury, putting on one side incomplete tunnels and grooves on the surface of the bone. With regard to the latter, however, when they invaded the joint cavity the injury was liable to be more severe than a complete perforation, in consequence of the projection of comminuted fragments into the joint cavity near the line of reflection of the synovial capsule and ulterior interference with freedom of movement.

Fig. 55a.—Diagram of 'Butterfly' type.