This bone is often difficult to keep in place after dislocation, and even the most accurately fitted apparatus sometimes fails to effect its object, hence many varieties of collar and yoke have been devised by different surgeons to accomplish this purpose.
The Shoulder is dislocated in three directions, downwards, inwards, and backwards. These have subordinate varieties, but the signs depend chiefly on the direction of the greatest displacement.
Signs of dislocation into the axilla. When the bone is displaced below the glenoid fossa the acromion is prominent; underneath it, the surgeon feels a hollow instead of the head of the humerus, which the finger detects in the axilla. Movement of the shoulder is very limited and painful If the elbow is rotated while the finger is in the armpit, the head will be found to move with the rest of the bone.
If the head of the bone is carried more inwards on to the ribs, it can be seen and felt near the clavicle; the hollow is again readily detected below the acromion, while the axis of the arm is altered, being directed inside its proper position.
When the bone is carried backwards the head is plainly felt on the scapula below the spine.
For the reduction of these dislocations several plans are employed. When recent the two first displacements can generally be restored without chloroform, but if the patient is muscular it often saves time and pain to produce anesthesia before attempting to replace the bone.
Fig. 61.—Reducing a dislocated shoulder by the heel in the armpit.
By the heel in the axilla (fig. 61).—The patient lies flat on a couch; the surgeon pulling off his boot from the left foot if he has to reduce a left dislocation, and vice versâ the right boot, seats himself on the couch facing the patient. Putting his unbooted foot into the armpit, he grasps the forearm with both hands and pulls steadily downwards. When the head of the bone is disengaged the muscles draw it into the socket, and the movements of the limb become at once easy and natural. The arm must then be fixed to the side by a roller for a fortnight, and the shoulder is wetted with an evaporating lotion to allay the pain and inflammation resulting from the laceration of the soft parts. Should the surgeon’s strength be insufficient for the requisite extension, a jack towel may be attached in a clove hitch round the wrist and held by an assistant, who standing behind the surgeon draws steadily in the same direction.
To make a clove hitch.—Grasp the towel in the left hand, the little finger being downwards, then pronating the right hand till the little finger is upmost, seize the towel below the left hand; if the wrists are then rotated in opposite directions the towel will be drawn into two loops, of which the ends cross above the connecting part between the loops (see fig. 62); if one hand holds the loops and the other pulls the ends, the loops will be found not to slip, however tight the ends are pulled.