Chapter 12. Injuries to the shoulder girdle and upper limbs

The scapula, clavicle, humerus, forming acromioclavicular, sternoclavicular, scapulohumeral joints with a strong ligamentous apparatus, are the basis of the shoulder girdle. Anatomically, the bone base of the upper limb girdle is represented by the scapula and clavicle.

Together with the ligamentous apparatus and the surrounding muscles, the shoulder girdle forms a stable connection through the sternoclavicular joint with the axial skeleton, being a reliable support together with the scapular-costal synchondrosis for the function of the entire arm and a kind of shock absorber in case of sudden movements and external influences in case of injury.

The scapula, which is mobile and well covered with muscle mass, is injured relatively infrequently (1-2.5% of all fractures of the musculoskeletal system). Damage to the less protected and more rigidly connected to the chest of the clavicle occurs in 12-18% of cases.

Scapular fractures

Mechanism of injury

Fractures of the scapula body occur when a significant force is struck (direct mechanism) and are often combined with fractures of the underlying ribs (II-VII), compression fracture of the thoracic vertebrae. The same impact from top to bottom with the point of application over the acromial or coracoid processes of the scapula may be accompanied by their fractures.

Fracture of the neck of the scapula with displaced fragments can be caused by impact from the front or from the back.

Marginal fractures of the glenoid cavity can be caused by a fall both on the outer surface of the shoulder (direct mechanism) and on the area of the bent elbow joint with the transmission of a strong blow through the head of the humerus (indirect mechanism).

Avulsion fracture of the apex of the coracoid process can occur with a sharp tension of the muscles attached to it.

Classification

There are fractures of the body and angles of the scapula, acromial and coracoid processes, spine, neck of the scapula, pear-shaped cavity (Fig. 12.1).

Fig. 12.1. Fractures of the scapula: 1 - neck; 2 - bottom corner; 3 - top corner; 4 - longitudinal body; 5 - coracoid process; 6 - acromial process

Diagnosis

Local soreness, swelling, abrasions and bruises are noted. Injuries to the scapula may be accompanied by rib fractures, including those complicated by injury to the lung with the development of pneumo- and/or hemothorax.

Fractures of the scapula body are usually not accompanied by significant displacement of fragments due to the surrounding muscle mass. This can make diagnosis difficult.

If there is a fracture in the area of neck of the scapula, a displacement of the articular area down and anteriorly often appears. In these conditions, the humeral process of the scapula protrudes, while the coracoid process sinks dawn. This fracture differs from the anterior dislocation of the shoulder by the absence of springy resistance during movements in the shoulder joint.

Marginal fractures of the articular cavity are characterized by sharp pains during movements in the shoulder joint and are accompanied by an accumulation of blood in the articulation (hemarthrosis).

Fracture of the acromial process is accompanied by deformation and sharp soreness over the fracture site, increased pain with tension of the deltoid muscle.

Radiologic Assessment

Clinical symptoms are sometimes scarce, so two-plane X-rays are mandatory. In doubtful cases, CT is performed.

Pre-hospital care

Pain relief - by general analgesics. Transport immobilization is carried out with a soft bandage (scarf or Desault), after which the victim is sent to a trauma hospital.

Treatment

The general principle in the conservative treatment of scapular fractures is the use of abduction fixation dressings.

In case of fractures of the body or the angle of the scapula, the limb is placed on a diverting splint with an angle of abduction in the shoulder joint up to 90° and flexion in the elbow joint up to 30°, which contributes to the creation of a relaxed state for the muscles of the shoulder girdle. Treatment on abduction splints allows starting TE from the first days for the hand, wrist, and elbow joints. Ability to work is restored after 4-6 weeks.

Fractures of the shoulder blade body without displacement well-splinted by muscle mass can be treated in a scarf bandage applied for 3-4 weeks.

For fractures in the area of the scapula neck with displacement, skeletal traction is performed behind the olecranon on the abduction splint. The fixation period is up to 4 weeks, after which movements in the shoulder joint are allowed. The ability to work is restored after 1.5-2 months. Fractures of the acromial process of the scapula without displacement should be immobilized on the abduction splint for 4-5 weeks.

Surgical treatment (open reduction with submerged osteosynthesis or arthroplasty) is the method of choice for displaced fractures of the glenoid cavity and can also be used for fractures of the scapula of other locations with displacement.

Clavicular fractures

Fractures of the clavicle on average account for about 15-18% among other fractures of the musculoskeletal system.

Anatomical and physiological features

The clavicle is the most important link in the shoulder girdle. Along with the scapula, it forms acromioclavicular joint and is associated with the acromioclavicular and coracoclavicular ligaments. Sternoclavicular articulation is strengthened by the sternoclavicular and costoclavicular ligaments. The subclavian artery and vein, as well as the subclavian part of the brachial plexus, pass close to the lower surface of the middle third of the clavicle.