The condition is also met with in epileptics; and it is generally found that the head of the bone is deficient, as a result either of fracture or disease; that the muscles which naturally support the joint are atrophied or torn; and that the capsule is unduly lax.
#Sprain# of the shoulder-joint is comparatively rare, because of the wide range of movement of which it is capable. The region of the shoulder becomes swollen and tender to pressure, the point of maximum tenderness being over the front of the joint, just below the acromion process; pain is elicited also when the ligaments or tendons are put upon the stretch.
#Contusion# of the region of the shoulder, on the other hand, is exceedingly common. In most cases it is merely the deltoid muscle and the subcutaneous tissue over it that are bruised, but sometimes a haematoma forms either in the muscle or in the sub-deltoid bursa. There is pain on moving the limb, and the patient may be unable to abduct the arm at the shoulder-joint. Under treatment by ma.s.sage and movement, the symptoms usually pa.s.s off completely in two or three weeks. The affections of the _bursa_ are described elsewhere.
In other cases, the cords of the brachial plexus above the clavicle are stretched, or the axillary nerve is bruised, and these injuries are liable to be followed by prolonged pain, loss of abduction, and stiffness in the arm. The deltoid frequently undergoes considerable atrophy, and there is severe neuralgic pain in the axillary nerve, especially marked in the region of the insertion of the deltoid.
In addition to maintaining the limb in the abducted position, it is necessary to keep up the nutrition of the muscles by ma.s.sage and electricity.
FRACTURE OF THE SCAPULA
Fractures of the scapula may implicate the body, the surgical neck, the acromion, or the coracoid process. They are rarely compound.
#Fracture of the Body.#--Considering its exposed position, the body of the scapula is comparatively seldom fractured, doubtless because of its mobility, and the support it receives from the elastic ribs and soft muscular cushions on which it lies. Apart from gun-shot injuries, it is most frequently broken by a severe blow or crush. The scapula presents two natural arches--one longitudinal, the other transverse--and when the bone is crushed or struck, the force produces fracture by undoing its curves (E. H. Bennett). A main fissure usually runs transversely across the infra-spinous fossa, and secondary cracks radiate from it (Fig. 26). In other cases the line of the primary fracture is longitudinal, pa.s.sing through the spine and involving both fossae.
[Ill.u.s.tration: FIG. 26.--Transverse Fracture of Scapula, with fissures radiating into spinous process and dorsum.]
The _clinical features_ are obscured by swelling of the overlying soft parts. Crepitus may sometimes be elicited by placing one hand firmly over the bone, and with the other moving the arm and shoulder. When the spine is implicated, the fragments may be grasped and made to move one upon another. The displacement, which usually consists in overlapping of the fragments--although sometimes they are drawn apart--is partly due to the action of the serratus anterior and teres major muscles, and partly depends on the direction of the force.
Movement is restricted and painful. Osseous union usually takes place rapidly, and although displacement often persists, the function of the limb is unimpaired.
_Treatment._--As these fractures are usually complicated by other injuries, especially of the thorax, and are accompanied by severe shock, it is necessary to confine the patient to bed. It is usually sufficient to fix the arm and shoulder to the chest wall by a firm binder, in the position which admits of the most complete apposition of fragments. This retentive apparatus is employed for about three weeks, after which the patient is allowed to use his arm. The bandages are removed daily to admit of ma.s.sage.
#Fracture of the surgical neck of the scapula#, although a rare accident, is of importance, as it is liable to be mistaken for dislocation of the shoulder. The line of fracture runs through the scapular notch, downwards and laterally to the lower margin of the glenoid, so that the glenoid and the coracoid process are separated from the rest of the bone.
The coraco-acromial and coraco-clavicular ligaments are usually torn, and the detached fragment, along with the head of the humerus, sinks into the axilla, causing a flattening of the shoulder, and leaving a depression below the projecting acromion. These signs may be obscured by the general swelling of the shoulder. The arm may be lengthened about an inch. By supporting the arm the deformity is at once reduced, but recurs as soon as the support is withdrawn. Crepitus is usually detected on carrying out this manipulation; and the coracoid process is found to move with the arm and not with the scapula. By these tests, and by the X-rays, this injury is distinguished from a dislocation.
A partial fracture carrying away the lower part of the _glenoid cavity_ simulates a sub-glenoid dislocation. This is, however, a rare injury.
The _treatment_ consists in bracing back the shoulders and supporting the elbow, and this is most satisfactorily done by a body bandage and sling for the elbow, as for fracture of the middle third of the clavicle. Pa.s.sive movements and ma.s.sage are employed from the first.
#Fracture of the acromion process# may result from a blow or fall on the shoulder. It is often overlooked on account of the swelling resulting from bruising of the soft parts, and the absence of marked displacement. On palpation, crepitus and an irregularity at the seat of fracture may sometimes be detected. The shoulder is slightly flattened, and abduction of the arm is difficult. In rare cases the fracture pa.s.ses into the acromio-clavicular joint, and is a.s.sociated with dislocation of the clavicle.
In connection with this fracture, reference must be made to a condition frequently met with, in which the epiphysial portion of the acromion is found to be separate from the body of the process--_separate acromion_. This is by some (Symington, Hamilton) looked upon as a want of union of the epiphysis, but the weight of evidence seems to prove that it is rather of the nature of an un-united fracture at this level, even when, as sometimes happens, it is bilateral (Struthers, Arbuthnot Lane).
Between the fourteenth and twenty-second years a true _separation of the epiphysis_ may be met with, but it is seldom possible to make a positive diagnosis of this injury. As is the case in all fractures of the acromion, bony union seldom takes place.
The _treatment_ is the same as for fracture of the lateral end of the clavicle.
#Fracture of the coracoid process# is rare. It may result from direct violence, such as the recoil of a gun, but it is more often an accompaniment of dislocation of the shoulder or of the lateral end of the clavicle upward. As the coraco-clavicular ligaments usually remain intact, there is no displacement; but when these are torn the coracoid is dragged downwards and laterally by the combined action of the pectoralis minor, biceps, and coraco-brachialis muscles. Crepitus may be elicited on moving the fragment. _Separation of the epiphysial portion_ of the coracoid may occur up to the seventeenth year.
The _treatment_ consists in placing the arm across the front of the chest, to relax the muscles causing the displacement, and retaining it in that position by a sling and roller bandage.
FRACTURE OF THE UPPER END OF THE HUMERUS
It is most convenient to study fractures of the upper end of the humerus in the following order: (1) fracture of the surgical neck; (2) separation of the epiphysis; (3) fracture of head, anatomical neck, or tuberosities.
[Ill.u.s.tration: FIG. 27.--Fracture of Surgical Neck of Humerus, united with Angular Displacement.]
#Fracture of the Surgical Neck.#--The surgical neck of the humerus extends from the level of the epiphysial junction to the insertion of the pectoralis major and teres major muscles, and it is within these limits that most fractures of the upper end of bone occur. This fracture is most common in adults, and usually follows direct violence applied to the shoulder, but may result from a fall on the hand or elbow, or from violent muscular action, as, for example, in throwing a stone. It is usually transverse, and there is often little or no displacement, the fragments being retained in position by the long tendon of the biceps and the long head of the triceps. When the fracture is oblique, the fragments are often comminuted, and sometimes impacted. The displacement of the upper fragment seems to depend upon the att.i.tude of the limb at the moment of fracture. When the upper arm is approximated to the side, the upper fragment retains its vertical position, but is slightly rotated laterally by the muscles inserted into the greater tuberosity, while the lower fragment is drawn upwards and medially towards the coracoid process by the muscles inserted into the inter-tubercular groove and the longitudinal muscles of the upper arm, and can be felt in the axilla. The elbow points laterally and backwards, and the upper arm is shortened. The shoulder retains its rotundity, but there is a slight hollow some distance below the acromion. On grasping the elbow and moving the shaft, it is found that the head and tuberosities do not move with it, and unnatural mobility and crepitus at the seat of fracture may be detected. When the upper arm is abducted at the moment of fracture, the upper fragment is retained in that position by the lateral rotator and abductor muscles inserted into it, while the lower fragment pa.s.ses upwards and medially.
[Ill.u.s.tration: FIG. 28.--Impacted Fracture of Neck of Humerus, in man aet. 75.
(Sir H. J. Stiles" case. Radiogram by Dr. Edmund Price.)]
Although there is sometimes overlapping and broadening after union, beyond some limitation of the range of abduction the usefulness of the limb is seldom impaired.
_Treatment._--Ma.s.sage, by allaying spasm of the muscles, soon overcomes the moderate amount of displacement which is usually met with. Further, the skin surfaces of the axilla having been separated by a thin layer of cotton wool, a sling is applied to support the wrist, and the arm is bound to the side by a body bandage.
In comminuted fractures and those with marked displacement, a general anaesthetic may be required to ensure accurate reduction; and to maintain the fragments in apposition, and to avoid any limitation of abduction after union, the limb may be fixed in the position of abduction at a right angle by means of a Thomas" arm splint with swivel ring, and extension applied, if necessary, to maintain this att.i.tude. After a week or ten days the patient is allowed up, wearing an abduction frame (Fig. 29), or a splint, such as Middeldorpf"s, which consists of a double inclined plane, the base of which is fixed to the patient"s side, while the injured arm rests on the other two sides of the triangle. Ma.s.sage and movement are employed daily.
[Ill.u.s.tration: FIG. 29.--Ambulatory Abduction Splint for Fracture of Humerus.]
Should these measures fail, the fracture may be exposed by an incision carried along the anterior border of the deltoid, and the ends mechanically fixed, after which the limb is put up in the abducted position for three or four weeks. Ma.s.sage is commenced on the second or third day. Union is usually complete in about four weeks.
#Separation of Epiphysis.#--The upper epiphysis of the humerus includes the head, both tuberosities, and the upper fourth of the inter-tubercular groove. On its under aspect is a cup-like depression into which the central pyramidal-shaped portion of the diaphysis fits.
This epiphysis unites about the twenty-first year.
[Ill.u.s.tration: FIG. 30.--Radiogram of Separation of Upper Epiphysis of Humerus.]
Traumatic separation is met with chiefly between the fifth and fifteenth years, and is most common in boys. It usually results from forcible traction of the arm upwards and away from the side, as in lifting a child by the upper arm, or from direct violence, but may be caused by a fall on the lateral side of the elbow.
The epiphysis, especially in young children, may be separated without being displaced, or the displacement may be incomplete.
When the epiphysis is completely separated from the shaft, the clinical features closely resemble those of fracture of the surgical neck, and the diagnosis is made by a consideration of the age of the patient, and the m.u.f.fled character of the crepitus, when it can be elicited. The upper end of the diaphysis forms a projecting ridge which may be felt below and in front of the acromion. The diagnosis can usually be established by the use of the X-rays (Fig. 30).
Dislocation is rare at the age when separation of the epiphysis occurs.
Reduction is often difficult on account of the periosteum and other soft tissues getting between the fragments, and on account of the small size of the upper fragment. Union almost invariably results, but the growth of the limb may be interfered with and its shape altered, especially when the injury occurs at an early age and its nature is overlooked.
_Treatment._--This injury is treated on the same general lines as fracture of the surgical neck. General anaesthesia is almost always necessary to secure satisfactory reduction, and retention is most easily secured if the patient is confined to bed with the upper arm fixed in the fully abducted position. Operative treatment is called for in exceptional cases.
#Fractures of the Head, Anatomical Neck, and Tuberosities of Humerus.#--These fractures are met with as accompaniments of dislocation of the shoulder, and as results of gun-shot injuries, blows, or falls.
In sub-coracoid dislocation the _head_ of the humerus may be indented by coming in contact with the anterior edge of the glenoid cavity (F.
M. Caird).
The _anatomical neck_ may be fractured in an old person by a direct blow on the shoulder. In a few cases the fracture is entirely intra-capsular, the head of the bone remaining loose in the cavity of the joint. As a rule, however, the fracture pa.s.ses laterally and implicates the tuberosities. In some cases there is impaction, and in others comminution of the fragments. The use of the X-rays has shown that in many cases in which prolonged stiffness has followed a severe blow of the shoulder, there has been a fracture of the anatomical neck.
The _tuberosities_ may be implicated in other fractures in this region and in dislocation of the shoulder; and either of them may be separated by muscular contraction or by direct violence.
_Clinically_ all these injuries are difficult to diagnose with accuracy, and, without the use of the X-rays, it is impossible in many cases to go further than to say that a fracture exists above the level of the surgical neck. Fracture of the anatomical neck is attended with little deformity beyond slight flattening of the shoulder and sometimes slight shortening of the upper arm.
When the _great tuberosity_ is torn off, considerable antero-posterior broadening of the shoulder may be recognised by grasping the region of the tuberosities between the fingers and thumb. Crepitus can be elicited on rotating the humerus. At the same time it will be recognised that the tuberosity does not move with the shaft. Firm union, with considerable formation of callus and some broadening of the shoulder, usually results, but the usefulness of the joint is not necessarily impaired. There may, however, be prolonged stiffness and impaired movement from adhesion; or pain and crackling in the joint may result from arthritic changes like those of arthritis deformans.
_Treatment._--These fractures are treated on the same lines as fracture of the surgical neck of the humerus.
The combination of fracture of the upper end of the humerus with dislocation of the shoulder has already been referred to.