**2. Shoulder arthroplasty for proximal humerus fractures**

### **2.1 Preoperative evaluation**

Adequate preoperative evaluation is critical in the management of patients with displaced proximal humerus fractures. The surgeon must have a good working knowledge as to the mechanism of injury and level of energy associated as this will give an indication of possible neurovascular injuries. The surgeon should attempt to determine whether the injury represents a fracture or a fracture/dislocation and evaluation of all available radiographic studies is beneficial. Previous history of osteoporosis will give an indication as to the quality of bone available for fixation. Past history of rotator cuff disease is helpful as a large rotator

Shoulder Hemiarthroplasty in Proximal Humerus Fractures 537

Arthroplasty for proximal humerus fractures is typically indicated for head split and head indentation fractures ›40% fractures, displaced 4-part fractures of the proximal humerus,

Fig. 2.

Fig. 3.

cuff tear will be associated with poor results with a humeral head replacement and may be an indication for reverse ball and socket prosthesis.

Physical examination may be limited in the acute fracture setting because of pain and swelling. The area of bruising is most commonly seen in the chest as well as the arm distal to the deltoid muscle. Bruising in the area of the deltoid itself is indicative of either direct trauma to this area or perforation of the deltoid by one of the fracture fragments. Neurovascular examination is typically limited because of pain and the status of the axillary nerve often cannot be determined prior to surgery. Distal pulses should be evaluated and compared to the contralateral side. Differences in distal pulses may be an indication for arteriogram. Displacement of the shaft medially in the area of the brachial plexus is also in indication to obtain an arteriogram prior to open reduction internal fixation. Range of motion testing is of no benefit in the acute fracture setting.

Radiographic examination should be limited to a trauma series which does not require the patient to move the arm. Three orthogonal views as described by Neer can adequately evaluate the fracture in the majority of cases (Neer 1990). (Figure 1) These include an AP view in the scapular plane, a transthoracic lateral view, and a Valpeau axillary view. All of these X-rays can be taken without removal of the arm from the sling. CT scan has been shown to improve the accuracy of fracture classification and is very beneficial in preoperative planning (Shrader et al 2005). (Figure 2)

Fig. 2.

536 Recent Advances in Arthroplasty

cuff tear will be associated with poor results with a humeral head replacement and may be

Physical examination may be limited in the acute fracture setting because of pain and swelling. The area of bruising is most commonly seen in the chest as well as the arm distal to the deltoid muscle. Bruising in the area of the deltoid itself is indicative of either direct trauma to this area or perforation of the deltoid by one of the fracture fragments. Neurovascular examination is typically limited because of pain and the status of the axillary nerve often cannot be determined prior to surgery. Distal pulses should be evaluated and compared to the contralateral side. Differences in distal pulses may be an indication for arteriogram. Displacement of the shaft medially in the area of the brachial plexus is also in indication to obtain an arteriogram prior to open reduction internal fixation. Range of

Radiographic examination should be limited to a trauma series which does not require the patient to move the arm. Three orthogonal views as described by Neer can adequately evaluate the fracture in the majority of cases (Neer 1990). (Figure 1) These include an AP view in the scapular plane, a transthoracic lateral view, and a Valpeau axillary view. All of these X-rays can be taken without removal of the arm from the sling. CT scan has been shown to improve the accuracy of fracture classification and is very beneficial in

an indication for reverse ball and socket prosthesis.

motion testing is of no benefit in the acute fracture setting.

preoperative planning (Shrader et al 2005). (Figure 2)

Fig. 1.

Fig. 3.

Arthroplasty for proximal humerus fractures is typically indicated for head split and head indentation fractures ›40% fractures, displaced 4-part fractures of the proximal humerus,

Shoulder Hemiarthroplasty in Proximal Humerus Fractures 539

Key goals in prosthetic replacement for proximal humerus fractures include atraumatic exposure of the fracture site with protection of the deltoid origin and insertion while avoiding further devascularization of the fracture fragments, proper positioning of the prosthesis both in terms of height and version, and secure anatomic fixation of the tuberosities. The exact indications for the use of reverse prosthesis in the management of proximal humerus fractures is not well understood currently and is undergoing a period of development and research. Surgery is recommended within 7-10 days after the patient is cleared medically. Delay beyond this time makes dissection more challenging due to early fibrosis. Surgery must be followed by a safe physical therapy program which allows

This surgery is typically performed under interscalene block anesthesia and general anesthesia. Relaxation during surgery decreases the pull of the pectoralis major and improves exposure. Interscalene block is contraindicated in the face of documented neurologic injury. This block results in excellent postoperative pain relief when indicated. The patient is placed in the beach chair position with the back of the table elevated approximately 30°. The patient is placed at the edge of the operating table with a bolster along the medial border of the scapula to stabilize this structure during surgery. Lateral placement of the arm allows extension off of the table for exposure and access to the humeral shaft. A well-padded neurosurgical head rest allows increased exposure and access to the superior shoulder and a short arm board supports the elbow without blocking access to the arm. All bony prominences are well-padded. A fluoroscan is utilized from above to allow evaluation of the fracture itself and tuberosity positioning. (Figure 6) Broad-spectrum antibiotics are routinely used. Surgical approach is planned to contribute minimal additional trauma to the soft tissues and vascular structures in the area of the proximal humerus. In situations in which the humeral head is displaced into the axilla in the area of the brachial plexus, caution must be exercised in its removal as this can result in

adequate healing of the tuberosities while avoiding excessive stiffness.

hemorrhage. Assistance from a vascular surgeon may be required in such cases.

Fig. 5.

**2.2 Operative technique** 

and 4-part fracture/dislocations. In these cases, the proximal humerus does fracture in a very characteristic pattern. The fracture line between the greater and lesser tuberosity typically lies directly posterior to the bicipital groove so that the lesser tuberosity fracture typically also contains the bicipital groove and a small portion of the greater tuberosity. (Figure 3) The remainder of the greater tuberosity often fractures away from the shaft and lesser tuberosity with a characteristic "V" shaped pattern of bone leaving a distinctive defect in the proximal shaft which can be used in realigning the fracture fragments anatomically. (Figure 4) Variable amounts of head fragment may still be attached to a tuberosities. A small portion of the calcar typically stays attached to the humeral head fragment. (Figure 5)

Fig. 5.

538 Recent Advances in Arthroplasty

and 4-part fracture/dislocations. In these cases, the proximal humerus does fracture in a very characteristic pattern. The fracture line between the greater and lesser tuberosity typically lies directly posterior to the bicipital groove so that the lesser tuberosity fracture typically also contains the bicipital groove and a small portion of the greater tuberosity. (Figure 3) The remainder of the greater tuberosity often fractures away from the shaft and lesser tuberosity with a characteristic "V" shaped pattern of bone leaving a distinctive defect in the proximal shaft which can be used in realigning the fracture fragments anatomically. (Figure 4) Variable amounts of head fragment may still be attached to a tuberosities. A small portion of the calcar typically stays attached to the humeral head

fragment. (Figure 5)

Fig. 4.
