Manual of Surgery Volume Second: Extremities—Head—Neck. Sixth Edition.

by Alexis Thomson; Alexander Miles

Displacement of the scapula upwards and laterally has been observed as a result of partial paralysis of the trapezius when the nerves supplying it have been divided in removing tuberculous glands from the neck. In these acquired displacements, treatment is directed towards the nerve lesion and towards the improvement of the muscles by electricity, massage, and exercises; when the paralysis of the trapezius is permanent, the disability is gradually overcome by the compensatory hypertrophy of the levator muscle.

Congenital Dislocation of the Shoulder.—This rare condition is usually bilateral, and is associated with other congenital defects. The glenoid cavity is deformed or absent, and the dislocation may be sub-coracoid, sub-acromial, or sub-spinous. The movements of the arm are restricted, and the development of the extremity as a whole is imperfect. It is sometimes possible to reduce the dislocation by manipulation, or, if this fails, by operation. Unilateral dislocation is sometimes mistaken for dislocation that has occurred during delivery and vice versa.

Habitual Dislocation is described on [p. 65].

Paralytic Deformities—Paralytic Dislocation of the Shoulder.—The muscles in the region of the shoulder may have their innervation interfered with as a result of various conditions, of which poliomyelitis and injuries of the brachial plexus at birth are the most important. The capsular ligament of the shoulder-joint, being no longer kept tense by the scapular muscles—especially the deltoid and lateral rotators—becomes relaxed, and is gradually stretched by the weight of the arm. The appearances are characteristic; the muscles of the shoulder are wasted, the acromion is prominent, and between it and the upper end of the humerus there is a marked hollow into which one or more fingers may be inserted. The arm hangs flaccid by the side, rotated medially and pronated, and moves in a flail-like fashion in all directions, the patient having little control over it. The best results are obtained by the transplantation of muscles, the trapezius being detached from the clavicle and stitched to the surface of the deltoid, and the upper arm fixed in the position of horizontal abduction with the arm rotated laterally and supinated. Bradford inserts a portion of the trapezius into the humeral insertion of the deltoid. When these methods are impracticable, the upper arm may be fixed to the trunk by some form of apparatus, or arthrodesis is performed so that the movements of the scapula are communicated to the upper arm; the best attitude for ankylosis is one of abduction with medial rotation, so that the hand can be brought to the mouth.

In cases of poliomyelitis, when all the muscles governing the elbow are paralysed while the muscles of the hand have escaped, it may be of great service to fix this joint permanently at rather less than a right angle. This may be effected by arthrodesis, or by removing an extensive diamond-shaped portion of skin from the flexor aspect of the joint and bringing the raw surfaces together, commencing the stitching at the lateral apices of the gap.

Fig. 166.—Arrested Growth and Wasting of Tissues of Right Upper Extremity, the result of Anterior Poliomyelitis in childhood.

Congenital Dislocations at the Elbow.—The head of the radius may be dislocated forwards, backwards, or laterally—usually in association with imperfect development of the radius and of the lateral condyle of the humerus. When the displaced head of the bone interferes with supination, or with extension, it should be removed. Congenital dislocation of both bones of the forearm is extremely rare.

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.