Cubitus varus is the reverse of cubitus valgus. It is more common, is always pathological, and is nearly always a result of fracture of the lower end of the humerus or separation of the lower humeral epiphysis and subsequent interference with growth. These deformities may be corrected by supra-condylar osteotomy of the humerus.
Fig. 167.—Lower end of Humerus from case of Cubitus Varus.
Synostosis of the superior radio-ulnar joint is a rare congenital condition, in which the hinge movements at the elbow are free, but supination is impossible; an attempt may be made by operation to form a new joint.
Volkmann's ischæmic contracture of the muscles of the forearm, resulting in the production of claw-hand, is described in Volume I., p. 415.
Deformities of the Forearm and Hand.—The radius may be absent completely or in part, frequently in combination with other malformations. The most evident result is a deviation of the hand to the radial side—one variety of club-hand. The forearm is shortened, the ulna thickened and often bent, and the thumb and its metacarpal bone are often absent, so that the usefulness of the hand and arm is greatly impaired ([Fig. 171]). For this condition Bardenheuer devised an operation which consists in splitting the lower end of the ulna longitudinally and inserting the proximal bones of the carpus into the cleft.
Congenital deficiency of the ulna is extremely rare.
Intra-uterine amputation by constriction of amniotic bands sometimes occurs ([Figs. 168], [169]).
| Fig. 168.—Intra-uterine Amputation of Forearm. | Fig. 169.—Radiogram of Arm of patient shown in [Fig. 168]. |