CHAPTER V.
FRACTURES OF THE SCAPULA.
Surgical Anatomy.— The freedom of motion in this bone and the fact that it is almost entirely surrounded by heavy muscles, account for the rarity with which it is fractured. Some portions of the scapula (spine and acromion process) are subcutaneous and accord- ingly more often injured. The acromial epiphysis usually joins the remainder of the bone between the eighteenth and twenty-fifth
Figs. 46 and 47. — A^'entral and dorsal surfaces of the right clavicle. A.. Acromion process; C, Coracoid process; G., Glenoid cavity.
years, although it may remain ununited throughout life. This condition has been mistaken for fracture. The attachments of the deltoid and trapezius tend to prevent displacement when this portion of the bone is broken. The attachment of these muscles and the heavy fibrous tissue surrounding the acromion and spine explain the difficulty of eliciting crepitus in the presence of fracture in this region. When, however, these structures are lacerated
37
38 FRACTURES AND DISLOCATIONS
sufficiently to allow displacement, crepitus, abnormal mobility and deformity are recognized without difficulty. If the fracture is internal to the acromio-clavicular articulation we have a condition closely resembling dislocation of the outer end of the clavicle.
Fracture of the coracoid is an extremely rare occurrence. It has been broken as the result of muscular action due to the pull of the short head of the biceps, coraco-brachialis and pectoralis minor. Epiphyseal separation of this process has been known to occur
Fig. 48. — ^View of the same bone from the axillary border. Note the relation of the coracoid and acromial processes to the glenoid cavity.
prior to the seventeenth year, at which time ossification makes it continuous with the rest of the bone.
Fracture of the glenoid cavity usually results from violence transmitted through the head of the humerus. It may exist as a complication of fracture- or dislocation of the humeral head. Fracture of the neck of the scapula may occur from similar causes. The thinnest and best protected portion of the bone is the body. Fracture rarely occurs in this region, but when it does it is almost invariably the result of direct violence. The spring of the ribs supporting the scapula undoubtedly enables it to withstand greater violence, but when trauma is severe we may have fracture of the
FRACTURES OF THE SCAPULA
39
underlying- ribs as ^vell as of the body of the bone. When such is the case, the more superficial fracture may conceal the injury to the ribs. Fracture of the 'body is usually transverse below the spine. Comminution is sometimes observed and in rare instances
Fig. 49. — Fracture of the neck of the scapuhi.
the line of fracture may cross the spine. The attachments of the infraspinatus, subscapularis, serratus magnus, rhomboid and teres muscles are such that pronounced displacement rarely occurs and palpation is difficult.
40 FRACTURES AND DISLOCATIONS
Symptoms. — Loss of function, and pain (which is increased on motion) are always present. Deep respiration causes suffering, though the rapid shallow breathing, characteristic of fractures of the ribs, is absent. The body of the scapula may be grasped as shown in Fig. 50 w^hen abnormal mobility and crepitus are elicited, completing the list of symptoms.
Fracture of the acromion process produces localized pain, tender- ness, and sometimes limited mobility and crepitus. The symptoms vary with the position of the fracture in relation to the acromio- clavicular articulation. Fracture of the acromion, external to the acromio-clavicular joint, produces local pain and tenderness. Crepitus and abnormal mobility may be present on manipulation, but deformity is almost uniformly absent. Fracture of the acromion entering the articulation gives rise to symptoms closely resembling fracture external to the joint, though mo- tions of the shoulder are usually more painful. Fracture of the acromion internal to its articulation with the clavicle, is accom- panied by symptoms almost identical with dislocation of the outer end of the clavicle, especially if the muscular and fibrous attach- ments of the process have been torn sufficiently to allow deformity. The shoulder drops downward, forw^ard and inward, and undue prominence is observed at the outer end of the clavicle. Palpation reveals the acromial fragment attached to the outer end of the collar bone. Abnormal mobility of the displaced acromial frag- ment is present, but crepitus is absent unless the fractured surfaces have remained in contact.
Fracture of the coracoid gives rise to localized pain and tender- ness just below the junction of the middle and outer thirds of the clavicle. Displacement, if present, is very slight owing to the fact that the rhomboid and trapezoid ligaments are seldom torn. These ligaments securely hold the fragment in position against the actions of the attached muscles. The tip of the coracoid may be palpated if pressure is made at the proper point below the clavicle. It is impossible, however, to grasp the process between the fingers, and for this reason it is difficult to elicit crepitus and abnormal mobility.
Fracture of the surgical neck of the scapida gives a picture somewhat resembling dislocation of the shoulder, although the deformity is not characteristic of any type of shoulder luxation, and crepitus can usually be elicited by manipulation. Fracture of the glenoid cavity, especially a fragment from the anterior edge,
FRACTURES OF THE SCAPULA
41
is a complication sometimes occurring in dislocations of the shoulder, and results in spontaneous recurrence of deformity fol- lowing reduction. Crepitus may, or may not, be present.
Diagnosis. — A consideration of the symptoms occurring in frac- tures of different regions of the scapula should render the diagnosis in most cases eas}^ Fracture of the acromion and body are by far the most common injuries seen in this bone. Fracture of the surgical neck may, at times, be extremely difficult to differentiate from dislocations of the shoulder and fractures of the upper end of
Fig. 50, — Method of grasping the Ixidy of the scjipiihi in detect the presence of fracture. The fingers of the right hand are palpating the spine of the scapula.
the humerus. Deep palpation of the axilla may detect the glenoid cavity moving with the head in its inward displacement. Fractures of the glenoid cavity, surgical neck and coracoid, may require the use of the X-ray before diagnosis can be established. The fre- quency with which radiography reveals unsuspected conditions in and about the shoulder demonstrates the value of the X-ray as a routine measure in injuries of this region. The difficulty of diagnosis is greatly increased if the case is not seen for tw^enty-four or forty-eight hours following the accident. By this time the swelling and tenderness have so increased that less is learned from inspection or palpation, and manipulation of the parts is seriously objected to by the patient. An anesthetic is often neces-
42 FRACTURES AND DISLOCATIONS
sary to determine the condition, especially if the X-ray is not available.
Treatment. — The treatment must, of necessity, vary with the region and function of the portion of the bone injured. Fracture of the body of the bone calls for strapping of the chest in such a manner that the scapula will be immobilized. In addition the arm should be fixed to the side of the chest by a swathe or additional strapping. The Yelpeau bandage may be used to advantage, especially when reinforced with starch or plaster of Paris. Oppos- ing surfaces of skin should be protected by the interpoiition of some
Fig. 51. — Oblique strapping with adliebive planter to immobilize the body of the scapula.
absorbent material, such as cotton. In fracture of the acromial process, especially with displacement, the indications in treatment are similar to those of fracture of the clavicle. A Sayre's dressing, or modification, such as shown on page 24, will answer the purpose satisfactorily. Additional pressure directly over the fragment may be had by means of a strap of adhesive and pad of gauze appro- priately placed. In fracture of the coracoid process direct immo- bilization of the fragment "is hardly possible, yet the arm should be so fixed to the side as to prevent action of the three muscles attached to the process. The indications in the treatment of fractures of the surgical neck of the scapula are similar to those of fracture of the upper end of the humerus. The axillarj^ pad and plaster of Paris shoulder cap can, as a rule, be so applied that the fragment is held in proper reduction. (See Fig's. 132 to 140.) It is
FRACTURES OF THE SCAPULA 43
nsiially unwise to allow use of the forearm or hand in fractures of any portion of the scapula. In the less severe conditions the arm should at least be carried in a sling, while the remainder of the upper extremity is securely immobilized.
After-Treatment. — Union will usually take place within a month. AYhen fracture occurs in parts of the scapula which are subject to considerable strain, such as the neck of the bone or the acromion, internal to its articulation with the clavicle, immobilization should be maintained for about two weeks longer. The dressings should be carefully inspected daily for the first week to avoid loosening and slipping. If irritation of the skin occurs it should receive proper attention.
Prognosis. — Fractures of the body of the scapula seldom produce permanent impairment of function. Fractures of the surgical neck, and of the acromion w-ith displacement, may be followed by some loss of function, if not properly reduced. Perfect function is likelv to follow fibrous union of the coracoid.