#Cubitus Valgus# and #Cubitus Varus#.--When the normal arm hangs by the side with the palm of the hand directed forward, the forearm and upper arm form an angle which is open outwards--known as the "carrying angle"; it is usually more marked in women in association with the greater breadth of the pelvis and the relative narrowness of the shoulders. When this angle is increased, the attitude is described as one of _cubitus valgus_. This deformity may be acquired as a result of rickets, but more commonly it is due to fracture of the lateral condyle of the humerus, in which the separated fragment has been displaced upwards. _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. [Illustration: 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). [Illustration: FIG. 168.--Intra-uterine Amputation of Forearm.] [Illustration: FIG. 169.--Radiogram of Arm of patient shown in Fig. 168.] #Drop Wrist from Anterior Poliomyelitis.#--In this condition the capacity of extending the fingers is deficient or absent. Recovery can be confidently predicted if, on still further flexing the fingers, they can be voluntarily extended towards the point from which they are flexed (Tubby and Jones). Considerable improvement may result from fixing the hand by means of a splint in the attitude of dorsal flexion. The splint is removed at frequent intervals to allow of massage and other treatment being carried out, and it has usually to be worn for a period of one to two years. In some cases recourse should be had to arthrodesis.